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THE LIBRARY OF THE UNIVERSITY OF NORTH CAROLINA AT CHAPEL HILL THE COLLECTION OF NORTH CAROLINIANA C614.1 N8?v5 1979/31 _ UNIVERSITY OF N.C AT CHAPEL HILL lllillill 00034018704 FOR USE ONLY IN NORTH CAROLINA COLLECTION I Digitized by the Internet Archive in 2009 with funding from Ensuring Democracy through Digital Access (NC-LSTA) http://www.archive.org/details/northcarolinavit197902nort LEADING CAUSES OF MORTALITY North Carolina Vital Statistics 1981—Volume 2 LEADING CAUSES OF MORTALITY North Carolina Vital Statistics 1981—Volume 2 A A State Center For Health Statistics EC. Department of Human Resources DiTiason of Health Semes STATE OF NORTH CAROLINA James B. Hunt, Jr., Governor DEPARTMENT OF HUMAN RESOURCES Sarah T. Morrow, M.D., M.P.H., Secretary DIVISION OF HEALTH SERVICES Ronald H. Levine, M.D., M.P.H. State Health Director Margaret Woodcock, M.A., M.P.A. Asst. Director for Management Services STATE CENTER FOR HEALTH STATISTICS Charles J. Rothwell, M.B.A., M.S., Director September 1983 TABLE OF CONTENTS PREFACE I. INTRODUCTION A. Purpose and Organization B. Overview of Mortality in North Carolina II. TECHNICAL NOTES A. Changes in the Cause-of-Death Classification System . . B. Changes in Population Bases Due to the 1980 Census . . C. Mortality Rates Computation of Mortality Rates Interpretation of Mortality Rates Flagging Biased Rates D. Procedure for Geographic Clustering of Counties .... III. NORTH CAROLINA'S POPULATION AND HEALTH CARE RESOURCES ... 3- IV. GENERAL MORTALITY IN NORTH CAROLINA 4- V. MAJOR CARDIOVASCULAR DISEASE MORTALITY 5- A. Heart Disease Acute Myocardial Infarction Other Ischemic Heart Disease B. Hypertension With or Without Renal Disease C. Cerebrovascular Disease D. Atherosclerosis VI. CANCER MORTALITY 6-1 A. Total Cancer 6-3 B. Cancer of the Stomach 6-23 C. Cancer of the Colon, Rectum, and Anus 6-31 D. Cancer of the Pancreas 6-41 E. Cancer of the Trachea, Bronchus, and Lung 6-49 F. Cancer of the Female Breast 6-59 G. Cancer of the Cervix Uteri 6-67 H. Cancer of the Ovary and Other Uterine Adnexa 6-75 I. Cancer of the Prostate 6-83 J. Leukemia 6-91 TABLE OF CONTENTS (CONTINUED) Page VII. OTHER SELECTED CAUSES OF MORTALITY 7-1 A. Diabetes Mellitus 7-3 B. Influenza and Pneumonia 7-9 C. Chronic Obstructive Pulmonary Disease 7-19 D. Chronic Liver Disease and Cirrhosis 7-29 E. Nephritis, Nephrotic Syndrome, and Nephrosis 7-37 VIII. MAJOR EXTERNAL CAUSES OF MORTALITY 8-1 A. Accidents 8-3 Motor Vehicle Accidents 8-5 Accidents Excluding Motor Vehicles 8-15 B. Suicide 8-25 C. Homicide 8-35 IX. INFANT MORTALITY 9-1 X. MULTIPLE CONDITIONS PRESENT AT DEATH 10-1 lv CD O•— • UJ Q£ 11 O ex 0^ (X £ 0^ CD to PREFACE The State Center for Health Statistics has produced triennially a major publication describing North Carolina's mortality experience for a five-year period. Such a publication was due for 1975-79 data, but the change in 1979 from the Eighth to the Ninth Revision of the International Classification of Diseases (ICD) made it undesirable to combine pre-1979 cause-of-death data with data for 1979 and later years. Changes in the cause-of-death classification were described in detail in the abbreviated 1979 edition Leading Causes of Mortality . The standard format is resumed in this 1981 _ edition, with three-year rates (1979-81) replacing five-year rates. The delay in publishing this volume has been largely due to a delay in obtaining the 1981 population projections based on the 1980 census, which are used in the denominators of the death rates. This edition of Leading Causes of Mortality is the third major publication of its type on North Carolina's mortality experience. This volume includes statistical tables, maps, and graphs, as well as cause-specific discussions of trends, geographic patterns, risk factors, and recent research. An overview of the mortality experience in North Carolina is also presented. The tables in this report provide selected 1981 mortality statistics for counties, Department of Human Resources regions. Health Service Areas, and the state (see maps on preceding pages). More than a dozen of North Carolina's leading causes of mortality are depicted in these tables; in addition, various cancer sites and total infant mortality are included. Similar to the last major publication, multiple conditions present at death are included in this volume. This section highlights the 1982 publication Multiple Conditions Present At Death: A Special Study and presents the data for 1981 deaths. A separate technical notes section has been included in this publication. This section is necessary not only to discuss appropriate interpretation (s) of mortality rates and changes in both the ICD codes and population bases, but also to introduce two new statistical procedures used in this volume—Flagging Biased Rates and Geographic Clustering of Counties. Both procedures are discussed in detail in Section II and where relevant in the other sections. Special thanks go to Mr. Shannon Hallman of the Health Services Research Center, University of North Carolina at Chapel Hill for preparing Section III—North Carolina's Population and Health Care Resources. For the first time data have been included on nurse practitioners and physician assistants and on skilled nursing and intermediate care beds. If there are any questions concerning this publication, please contact: Delton Atkinson State Center for Health Statistics Division of Health Services P. 0. Box 2091 Raleigh, North Carolina 27602 (919) 733-4728 I. Introduction PURPOSE AND ORGANIZATION Although North Carolina has traditionally experienced low death rates, our status among states has worsened. In 1960, only seven of the 50 states had death rates lower than North Carolina, and this increased to 14 in 1970 (1). In 1981, 20 states had lower rates and three had the same rate (2). Furthermore, while many of the state's cause-specific rates are still below United States levels, North Carolina's age-adjusted rates are usually higher. For example, cerebrovascular disease, motor vehicle accidents, all other accidents and adverse effects, pneumonia and influenza, and nephritis, nephrotic syndrome, and nephrosis are causes for which North Carolina's 1981 adjusted rates were at least 10 percent above the corresponding United States rates. These facts represent a serious challenge to health officials throughout the state to (i) identify high-risk areas in order to strategically apply medical and other health services, and (ii) isolate those determinants of mortality that permit intervention. The data in this volume are intended to aid in these areas of investigation by providing information against which North Carolina's county and regional mortality may be assessed in the present and evaluated in the future. Ten sections comprise this edition of Leading Causes of Mortality . This section presents an overview of mortality experience in North Carolina as well as the purpose and organization of the document. Section II provides information concerning the calculation, interpretation, and appropriate use of adjusted and unadjusted rates. In past editions of this volume, readers were 1-3 cautioned about using adjusted rates with a small number of deaths in the numerator. For this and subsequent editions, problem rates have been "flagged" in the tables with an asterisk. The procedures used to determine which rates to flag are described in detail in Section II. Also, a new procedure used to depict geographic clustering of counties is discussed here. In Sections III-X, maps and tabular data describe North Carolina's recent experience with respect to population and selected health care resources, general mortality, cause-specific mortality (underlying causes), infant mortality, and multiple conditions present at death. Although the 1976 edition of this volume reported that some 3-year rates may have substantial random fluctuations, changes in coding of death certificates in 1979 necessitate the use of these rather than 5-year rates. The 1982 edition of Leading Causes of Mortality will show 4-year rates, and the 1983 and subsequent editions will again show 5-year rates. Table 1 on page 1-8 describes the selected cause-of-death categories in terms of codes from the ninth revision of the International Classification of Diseases (3). Altogether, the causes selected for examination in this report accounted for 87 percent of all North Carolina deaths during 1981. Description Of Maps This volume contains 81 computer-produced maps which depict data for the state's 100 counties. The maps on pages v and vi identify the four regions of the Department of Human Resources (DHR) and the state's six Health Service Areas (HSA's) . In Section III, five maps portray each county's relative status among the 100 counties with respect to population per primary care physician; population 1-4 per primary care physician, physician assistant, and nurse practitioner; population per registered nurse; population per short-term general hospital bed; and population 75+ per skilled nursing and intermediate care beds. These data together with information concerning county populations and county mortality levels should aid in the determination of areas most in need of increased health resources. In Sections IV-X, the mgps depicting geographical patterns in mortality should aid in the resolution of specific types of health promotion and health care needs. Two to four maps are generally shown for each cause-of-death category. Two maps depict the 1979-81 unadjusted death rate and the 1979-81 age-race-sex-adjusted death rate for each of the 100 counties. These two maps show six levels of death rates, where level one is the lowest rate interval and level six the highest . These maps should be viewed with extreme caution for causes where the number of deaths per county is small, since in these cases the rates may be very unstable. Users of the maps should note that the interval values indicated by the map legends are not necessarily continuous but reflect the actual range of values for each interval. A clustering routine from the Statistical Analysis System (SAS) was used to group counties that are "most like each other" with respect to their unadjusted rate and then their adjusted rate (4). This procedure may result in very large or very small groups depending upon how counties differ from one another. The other two maps for a particular cause may depict "spatial" clustering of two or more adjacent counties with high unadjusted and/or adjusted rates using a new procedure described in Section II. These maps are presented for a given cause only when a statistically significant spatial cluster is found to exist. Unlike the two full-page maps, these maps are presented in reduced form as part of the narrative and show one to three 1-5 interval levels of death rates, depending on the number of significant spatial clusters found, along with the significance level (i.e., p-value) . Description Of Tables Sections IV-X contain tables that summarize the recent mortality experience of counties, six Health Service Areas, four Department of Human Resources regions, and the state. Except in the case of infant deaths (Section IX) , a table corresponding to each cause-of-death category includes the following items of information: (1) the number of resident deaths occurring during 1981; (2) the 1981 death rate; (3) the number of resident deaths occurring during 1979-81; (4) the 1979-81 average annual death rate; (5) the 1979-81 average annual age-race-sex-adjusted death rate computed by the direct method (5). The formulas for calculating single- and multi-year rates are found in Section II. In this report, general mortality rates (all causes combined) are expressed as deaths per 1,000 population while cause-specific rates are expressed as deaths per 100,000 population. The infant death rates of Table 28, Section IX, are computed as the number of infant deaths per 1,000 live births. Multiple Conditions Present At Death Since 1975, multiple conditions present at death have been coded such that statistics are available for all conditions present at death as reported by the certifier. Three diseases in particular—hypertension, atherosclerosis, and diabetes—are considered associated conditions far more often than they are considered an underlying cause; hence, no maps are 1-6 displayed in Sections V and VII showing these deaths as an underlying cause. For the geographic clustering routine maps, only the 1979-81 age-race-sex-adjusted county rates for these conditions are displayed in Section X. Two of the three clustering maps displaying unadjusted rates showed patterns similar to those for adjusted rates, and thus are not presented, while the third (atherosclerosis) was not statistically significant. Tables in Section X show deaths crosstabulated by underlying cause and associated mentioned conditions, death frequencies for selected pairs of mentioned conditions, and death rates based on mentioned conditions rather than underlying cause. Rates are deaths with the condition mentioned per 100,000 population. 1-7 OVERVIEW OF MORTALITY IN NORTH CAROLINA Mortality in North Carolina has exhibited a general downward trend in this century. Numerous factors have contributed to this decline including changes in lifestyles, environment, age-race-sex distribution, risk factors, and the medical care system. In Sections IV through X of this report, these factors and others are considered in discussing each cause of death. This overview examines four general determinants of mortality, highlights some of the major mortality findings, and describes some of the risk factors which impact on a number of different causes. Further, this section looks at premature mortality in North Carolina using a concept called "years of life lost" which emphasizes mortality in the younger age groups (6). Determinants of Mortality A broad view of mortality determinants recognizes that medical care is only one aspect of health maintenance and that many health problems "arise from causes embedded in the social fabric of the nation as a whole" (7) . Accordingly, environment, lifestyle, biology, and medical care must all be considered as determinants of health. The natural and manmade physical environments are commonly recognized as having an important impact on health. For example, water mineral content and elevation have been cited as influencing the incidence of cardiovascular disease (8) . Of particular concern recently have been the health consequences of manmade environmental pollution. The proliferation of various chemical compounds is a central element of a high-technology, growth-oriented society. Ill health due to environmental pollution therefore can result from the 1-9 economic environment. Stricter governmental controls may be required in this area for those businesses that will not voluntarily weigh social costs into their economic calculations. Yet economic growth bears on health in ways other than the negative externalities of environmental pollution. Economic growth means jobs and income, both of which are central to individual and family well-being. Unemployment, economic poverty, and their social concomitants are inimical to mental and physical health. The poor, controlling a lesser share of economic and social resources, are subject to greater physical vulnerability to infectious agents, more economic uncertainty and associated stress, and more hazardous environments in homes and workplaces. They have fewer cushioning devices such as vacation or travel (9) . Thus controlled growth can have substantial health benefits if it is broadly based and environmentally sound. Lifestyle refers to those decisions by individuals that affect their health and over which they have some control. The degree of individual control over one's own decisions is a key question to answer in an evaluation of changing lifestyles as a health improvement strategy. Individuals' decisions are conditioned to a large extent by their position in the economic and social hierarchy. Self-destructive and violent behavior, for example, may reflect alienation due to a marginal position in the society. But policies to educate individuals about their health are much less complex and easier to sell politically than those aimed at modifying basic social and economic determinants of lifestyle and health. "Blaming the victim" by keeping the problem at the individual level may obscure the origins of disease in the socioeconomic environment. This is not meant to suggest that health education does not have its place. Certain population groups are more likely to engage in lifestyles that 1-10 increase mortality, and education programs that target these groups are an essential, though short-run, complement to policies oriented toward the environmental factors that condition lifestyle. Education about nutrition is likely to have a high health payoff among the poor and less educated, but only if they have enough money to buy proper food and the facilities to properly prepare it. A 1977 Rhode Island telephone survey indicated that the 30-39 year age group could be targeted as high-risk, based on health perception, weight, smoking, drinking, sleep habits, and stress. Education efforts aimed at relieving stress, which is much less publicized than other lifestyle factors and may affect smoking, drinking, and other behaviors, may be more productive. As shown in a recent North Carolina study (10) , income, education, and urban or rural residence may be important indicators and determinants of lifestyle, and successful education programs must consider variation along such dimensions. Targeting specific groups is likely to be more successful than generalized education or media campaigns. Biological factors are very pervasive determinants of mortality. The age, race, and sex of an individual are biologically determined and mortality rates vary consistently along these dimensions. Health is strongly tied to aging and the life cycle, some diseases that vary by race are thought to be genetically linked, and biological factors account in part for males and females having a different incidence of many diseases, with females living longer on the average. Some health consequences of age, race, and sex are, however, not biological in origin. Social stratification is in large part based on age, race, and sex differences, with the old, the nonwhite, and the female generally being lower on the social and economic hierarchy. Male mortality is higher partially as a result of aggressive, achievement-oriented 1-11 behavior that accompanies higher status positions (11), while higher nonwhite mortality is due in part to a lower position in the economic hierarchy (12). Many causes of disease are biological in origin. In North Carolina an estimated 150,000 persons are suffering from serious genetic disorders as evidenced by physical defects, mental retardation, and other health problems (13) . Forty percent of all children admitted to inpatient pediatric care are there because of genetic disorders (13). About one-half of all visual impairment difficulties are caused by genetic factors. Birth defects, of which about 80 percent are thought to be genetic in origin, are a leading cause of infant mortality. Some persons have a greater biological susceptibility to disease. Cancer, for example, may result from problems of the immunological system, in combination with the presence of external agents. Many parts of the medical care system function by reacting to health problems caused elsewhere, though in attempting to restore individuals to a full and productive life, this system becomes an important determinant of mortality levels. Disease prevention is also within the purview of the medical care system, as through innoculation against infectious diseases or patient education concerning the negative health consequences of certain lifestyles. Medical care personnel may also be involved in attacking certain environmental and biological causes of disease, though this type of activity has traditionally been carried out in the government or public sector. McKeown and Brown (14) present evidence suggesting that medical practice in the first half of the 19th century had very little to do with the large decline in mortality that took place in Western societies, but rather that transportation improvements, changes in the economic system that assured a more continuous and nutritious food supply, and improved sanitation practices urged on by reformers in the cities were responsible. After the practice of 1-12 antisepsis became widespread late in the 19th century, medical care became a much more positive factor in reducing mortality. During the first half of this century, the health and average life span of Americans improved considerably, due substantially to efforts in the medical sector to reduce infections and acute nutritional diseases. Major gains were observed in infant and maternal mortality. Medical care, however, may sometimes have negative health consequences. It has been estimated that infections acquired inside the hospital strike 1.5 million of the 33 million Americans hospitalized each year, adding to hospital costs by increasing lengths of stay and causing an additional 15,000 patient deaths (15). Inappropriate or unnecessary treatment may also increase mortality as well as health care costs. Risks, however, are always present even in proper medical treatment, and in most cases they are far outweighed by the potential benefits. In summary , a complete program to improve health status and reduce mortality must include environmental, lifestyle, biological, and medical care strategies. Too much emphasis in one area may, however, involve substantial opportunity costs due to neglect of other areas. For example, expenditures for genetic research, for environmental protection, or to improve substandard housing and below-poverty-level incomes could potentially have higher long run health payoffs than would the same amount expended just for medical care. The rise of heart disease and cancer as major killers is closely linked to changes in the economic environment, and medical treatment or attempts to modify individual behaviors are not by themselves likely to control these diseases. Sedentary occupations, increasing incomes and therefore food consumption (particularly of foods high in animal fat) , and drinking and smoking associated with stresses placed on the family and other primary support 1-13 institutions in a highly mobile society all underlie the rise in heart disease. The spiral of post-WWII economic production and increasing use of automobiles have led to more and more carcinogens in the air, water, and food. Cancer control is such a difficult policy area precisely because cancer prevention will require fundamental changes in the physical and therefore economic environment. Policies aimed at improving the medical treatment of cancer victims are probably easier to implement, but they do not deal with the basic problem. Successful strategies to deal with these and other leading causes of mortality must modify the basic causes of our modern ills. 1-14 Risk Factors Risk factors particular to each cause of death are discussed in separate sections of this volume, but there are some factors common to a number of different causes of death and these factors are summarized here. Two of the most pervasive factors contributing to U.S. mortality from various causes are high blood pressure and cigarette smoking . Higher levels of blood pressure have been shown to be associated with death from all cardiovascular diseases, diabetes mellitus, and cirrhosis of the liver (17,18). Most cases of high blood pressure are amendable to treatment; however many people either are not aware that they have high blood pressure or will not maintain the proper weight, diet, and medication regimen to control it. Cigarette smoking contributes to death from a large number of causes (17- 22) . A recent report by the U.S. Surgeon General (22) concludes that smoking is a major cause of lung cancer and of cancers of the larynx, oral cavity, and esophagus; that it is a contributory factor in the development of cancers of the bladder, pancreas, and kidney; and that approximately 30 percent of all cancer deaths are attributable to cigarette smoking. It has also been reported as a contributor in the development of chronic bronchitis and emphysema, pulmonary heart disease, myocardial infarction, aortic aneursym, and a wide variety of other vascular diseases. Smoking has important interactions with other factors. "It is now clear that smoking may act synergistically with ionizing radiation or asbestos to produce cancer of the upper respiratory and digestive tracts, with oral contraceptives to produce myocardial infarction, and probably with several dietary factors to produce both cancer and vascular disease". It may be that the low tar, low nicotine cigarette is less liable to cause lung cancer and chronic bronchitis, but no 1-15 less liable to produce vascular disease because of its carbon monoxide content. A substantial reduction in smoking -related disease and death is likely to come about only if a substantial number of smokers quit smoking. (19) Diet also has an important impact or certain causes of mortality. Over-eating may lead to obesity , which contributes to high blood pressure, diabetes, and cardiovascular disease. Diabetes is itself a risk factor for stroke and other cardiovascular diseases. In addition, the content of our moderr diet has important consequences for mortality. "Compared with our ancestors' diet, that consumed by present-day western populations is higher in intake of energy, of protein (especially animal protein), and of fat (especially animal fat), but lower in intake of fibre-containing cereal foods; this diet is associated with high rates of morbidity and mortality from degenerative diseases" (23). In particular, decreased intake of animal fat and protein, cholesterol, salt, sugar, and alcohol is recommended . Eyer (18) suggests, however, that reduction of animal fat in the diet may just redistribute cardiovascular deaths from coronary heart disease to stroke, and that reducing the total level of cardiovascular disease depends on reducing smoking and high blood pressure. Heavy alcohol consumption carries a risk of premature death greatly exceeding normal expectancy (24,25). "Vtfiile the lifestyle typical of many heavy drinkers contributes to this risk, the effects of alcohol per se account for a substantial part of the excess mortality" (24). In two Chicago studies, heavy drinkers had higher mortality from all causes, cardiovascular diseases, coronary heart disease, and sudden death, than could be entirely explained by their blood pressure, smoking, and weight (25). The mortality experience of 1-16 moderate drinkers, however, does not seem to differ notably from that of life-long abstainers (24). Mental disease may also increase mortality risk. One study (26) found that schizophrenic, manic, and depressive patients had a significant increase in mortality risk over that experienced by the general population of which the study group was a part. Mortality of a control group did not differ significantly from that of the general population. Better diagnosis and treatment of persons with mental diseases could help reduce the level of mortality. Social class has a very strong impact on mortality (12,20,27). "Social class gradients of mortality and life expectancy have been observed for centuries, and a vast body of evidence has shown consistently that those in the lower classes have higher mortality, morbidity, and disability rates" (12). The higher morbidity rates in lower status groups is an important observation since it indicates that their excess mortality is not merely attributable to a higher case fatality rate but is accompanied also by a higher prevalence of morbidity. Differences between white and nonwhite mortality rates can be attributed largely to social class differences. Persons in lower socioeconomic groups live in a more toxic, hazardous, and non-hygienic environment resulting in a broad array of disease consequences. Low education contributes to poor health practices and low income affects many aspects of health, including proper nutrition. Higher stress levels and differences in coping with stress also contribute to higher mortality among the poor (9, 12). Lower class persons generally receive less adequate medical care, though this probably does not account for a major portion of the social class differences in morbidity and mortality (12). Syme and Berkman (12) conclude that to reduce excess mortality among the poor " new 1-17 approaches must be explored emphasizing the primary prevention of disease in addition to those approaches that merely focus on treatment of the sick. It is clear also that such preventive approaches must involve community and environmental interventions rather than one-on-one preventive encounters." The male sex is another important factor associated with higher mortality. Males have higher mortality than females beginning at conception and this differential continues for every age group. A high ratio of males to females at conception declines to about 104:100 at birth until by age 70 females outnumber males approximately 3:2. In the United States, the male age-adjusted death rate is about 50 percent higher than that for females (28). Diabetes is the only major killer for which higher death rates are reported for women than men, a result due entirely to higher female rates at older ages. While there is a significant biological component contributing to higher male mortality (29), and in particular female hormones may lower the risk of coronary heart disease, Waldron (11) and others (12) have concluded that sex differences in behavior are a more important cause of higher male mortality than are inherent sex differences in physiology. "Each of the factors which we have identified as a major contributor to men's excess mortality involves a behavior which is more socially acceptable for males than for females, for example, aggressive competitiveness, working at physically hazardous jobs, drinking alcohol and, especially in the early part of the century, smoking cigarettes. The sex differential in smoking and alcohol consumption seems also to be linked to underlying attitudes, such as rebelliousness and achievement striving, which are fostered to a greater extent in males" (11). Waldron estimates that one-third of the difference between male and female death rates may be due to men's higher cigarette 1-18 smoking, with the major contribution via increased coronary heart disese, lung cancer, and emphysema. If in fact much of the sex difference in mortality is not due to biological factors, then substantial reductions in men's excess mortality can be achieved by cultural and behavorial changes. Social and lifestyle changes may also help to reduce female mortality. With the transition earlier in this century from infectious to degenerative diseases as the major causes of death, lifestyle became more important in affecting mortality experience, and the difference between male and female mortality rates increased steadily. In the 1970's, however, this increase slowed and female mortality relative to male mortality actually worsened for several age groups and for several leading causes (30). This may be associated with increased smoking (19) and the adoption of other "male" behaviors by women as job participation and mobility increase and traditional roles are modified. A number of risk factors have been reviewed that bear on many causes of death, and efforts to reduce excess mortality must involve consideration of these important precursors. 1-19 North Carolina Mortality Highlights • Life expectancy at birth has continued to increase reaching 70.0 years for white males, 78.5 years for white females, 63.6 for r.onwhite males, and 73.4 for nonwhite females in 1980. However, since 1960 life expectancy at birth has increased by about 3 years for white males and females, 4 years for nonwhite males, and 7 years for nonwhite females. Cveral 1 , the median age at death in 1981 was 70.4 years, up from 66.4 in 1970 and 28.1 in 1914 when N.C. deaths were first centrally recorded. • A total of 49,212 North Carolinians died in 1981. By race and sex, the deaths per 1000 population were slightly higher for nonwhites than whites (by 4%), but significant! y higher for males than females (by 34%). • Infant mortality declined in the past 10 years reaching 13.2 deaths per 1000 live births in 1981, from 24.1 in 1970. But despite this dramatic improvement, North Carolina's rate continues to rank among the highest in the nation; only 7 states had a higher rate in 1981. • Age-adjusted mortality rates show wide gaps in the overall risk of mortality for North Carolina males versus females and nonwhites versus whites. In the 1979-81 period, the male rate for both races was nearly double the female rate, and the nonwhite rate for both sexes remained more than 40 percent above the white rate. • Comparison of the 1981 N.C. age-race-sex-specific mortal ity rates with provisional rates for the U.S. during 1981 reveals the following excesses in North Carolina: White males: Ages 55-64 (15% above U.S. rate) White females: Ages 5-14 (23% above U.S. rate) 1-20 Nonwhite males: Ages 35-44 (31%), 45-54 (30%), 55-64 (18%), 65-74 (10%), 75-84 (14%) Nonwhite females: Ages 0-4 (10%), 45-54 (14%) Even after adjusting for age, race, and sex the eastern counties, especially the northeastern counties, seem to have consistently higher mortality rates. Based on adjusted rates, statistically significant spatial clusters exist in eastern North Carolina for total mortality, heart disease, stroke, motor vehicle accidents, infant mortality, total cancer, lung cancer, and cancer of the colon, rectum, and anus. The highest overall age-adjusted mortality rate for nonwhites is in the Southern Piedmont HSA while the highest age-adjusted rate for whites is in the Cardinal and Eastern HSAs. Further, race and sex ratios show that race differences in age-adjusted rates are greater in the western part of the state and sex differences are greater in the east. Based on the number of North Carolina deaths, the 10 leading causes in 1981 were (in descending order) heart disease, cancer, cerebrovascular disease, accidents, pneumonia/influenza, chronic obstructive lung disease, diabetes, suicide, chronic liver disease/cirrhosis, and homicide. However, based on the number of years of life lost prematurely for each cause, the 10 leading causes were heart disease, cancer, accidents, suicide, homicide, cerebrovascular disease, chronic liver disease/cirrhosis, pneumonia/influenza, chronic obstructive lung disease, and diabetes. Although age-adjusted homicide rates have declined for each race-sex group, this rate remains substantially higher for nonwhite males. 1-21 In 1981 about 40 percent of all homicide victims were nonwhite males; yet nonwhite males represented less than 12 percent of the total population. Nonwhite males have a greater risk of death from motor vehicle accidents at every age interval except the 15-24 age group where white males have the highest rate. Comparing the U.S. and N.C. unadjusted rates, mortality conditions in N.C. do not appear to be greater except in the case of cerebrovascular disease, nephritis/nephrosis, and accidents. However, adjusting for the state's more youthful age structure, mortality conditions in N.C. appear much less favorable with only a slight advantage in the case of cancer, chronic obstructive lung disease, and chronic liver disease/cirrhosis. Based on 1979 age-adjusted rates, even those advantages appear limited to females, with N.C. males of both races experiencing above-average risk in nearly every cause category. Cancer mortality appears to be rising faster in N.C. than in the U.S. In the last two years, the state's age-adjusted cancer death rate has risen about 2.5% (vs. 0.9% nationwide) with notable increases for cancer of the pancreas (19%) and cancer of the cervix uteri (26%). The former downward trend for cervical cancer appears to have stalled in recent years. Based on age-specific number of deaths from cervical cancer, there has been considerable random fluctuation with a sharp nonwhite drop in 1979 involving all age groups. Only for white women 55-64 has any consistent pattern of increase recently occurred. 1-22 • Both the state and the U.S. have recently experienced increases in pneumonia/influenza and chronic obstructive lung disease death rates. N.C.'s decreases in cardiovascular and accident mortality also reflect national trends, although 1979 to 1981 reductions in the risks of motor vehicle and other accidents were greater in the U.S. than in North Carolina. 1982 PROVISIONAL DATA Provisional North Carolina data show that the unadjusted rate for all deaths declined from 325.6 deaths per 100,000 population in 1981 to 807.0 in 1982. Cancer and chronic obstructive pulmonary disease appear to be the only causes with a rate increase in 1982. 1-23 Premature Mortality in North Carolina Since deaths were first centrally recorded in North Carolina, the leading causes of mortality have been ranked primarily according to number of deaths. North Carolina deaths in 1981 have been ranked in Table A for each race-sex group based on this traditional method. As shown, heart disease, cancer, and stroke (cerebrovascular disease) are the leading causes of death for each group, but the rankings of the other causes, as well as the size of the rates for the same cause, vary among the four groups. Rankings based only on number of deaths, however, do not necessarily indicate where medical and public health intervention strategies can most effectively be employed. Since death is postponable but not preventable, age at death is a very important factor to consider. Prevention of a death that would otherwise occur early in life could be assigned higher priority than prevention of a death later in life. A convenient method of ranking causes of death that incorporates age at death is by "years of life lost" (6). If the average life expectancy at birth for white males, for example, is 70 years, a death at age 65 would mean 5 years of life lost (on the average), while a death at age 40 would mean 30 life-years lost. An infant death results ir. 70 years of life lost, whereas, deaths at age 70 and over do not contribute to "life-years lost" for white males. Based on 1979-80 life tables for North Carolina (16), the life expectancies used here to calculate years of life lost were 70 for white males, 79 for white females, 64 for ronwhite males, and 73 for nonwhite females. For each death in a given cause group, age at death was subtracted from the appropriate life expectancy and all of these life-years lost were then summed up for that race-sex group, with deaths over the specified ages not counted. A rate of years of life lost per 100,000 1-24 population was then calculated for ranking the causes of death, so that comparisons can be made across race-sex groups. A more accurate method of calculating years of life lost may be to use an average expected remaining years of life for each age of death rather than an average life expectancy at birth. This method was considered too complicated for the present application, and probably would not result in rankings substantially different from those in Table B. It would place somewhat less emphasis on infant mortality since more years of life lost would be generated for the causes listed in Table B. Table B displays the leading causes of death ranked according to years of life lost per 100,000 population. Heart disease and cancer are still very important causes of death from this perspective, but other causes become much more prominent than before. Motor vehicle accidents account for more years of life lost for nonwhite males than any other cause, and the general seriousness of motor vehicle accidents as a life and health hazard is clearly shown in this table. Cancer becomes a much more important cause of death relative to heart disease from this perspective, since cancer decedents are about ten years younger on the average than are heart disease decedents. In fact, cancer accounts for more years of life lost for white females than any other cause. Infant deaths in 1981, about 8% of which are counted under causes (such as accidents) shown in Table B, accounted for 1322 years of life lost per 100,000 total population (compare column 1 of Table B) and therefore should be a key target for prevention. 1-25 a ~ (N m oo n r~ i1 oo <N <-t r- 10 vo en m H8 oO C/l O I 3*8" Is 3 j S o CM (o CM vo o r» 11 id § •d -3 1 I 1 >^SoNcuHvohci«roncNMr-tH OrHv^rooino -t o o co r~ n H io r- » vo «0 en in « <"> o *o r^ oi m fM PI ^ H ri H 1-26 * m in ^» n"> en ci >-t #-i t— m t (N in o\ t— 10 in r-i a I & i .o-\l*a*^ivoocoora\-^o\oomi.n-cioo 1-27 REFERENCES FOR SECTION I 1. United States Department of Health, Education, and Welfare. Public tteal th Service, National Vital Statistics Division. Vital Statistics of the United States, Volume II-Mortality (Part A) . I960 and 1970, Washington, D.C. 2. United States Department of Health and Human Services, Public Health Service, National Center for Health Statistics. "Annual Summary of Births, Deaths, Marriages, and Divorces: United States, 1981," Monthl y Vital Statistics Report . (PHS) 83-1120, Volume 30, Number 13, Hyattsville, Maryland, December 20, 1982. 3. World Health Organization. International Classification of Diseases : Manual of the International Statistical Classification of Diseases" , Injuries, and Causes of Death , Volumes I and II. Geneva, Switzerland, 1978. 4. SAS Institute Inc. SAS User's Guide: Statistics, 1982 Edition , Cluster Procedure. Cary, N.C. , 1982. 5. Grove, R.D. ; Hetzel , A.M. Vital Statistics Rates in the United States : 1940-1960 . Public Health Service Publication Number TsTf, DTs. Government Printing Office, Washington, D.C, 1968. 6. Weinman, J.C. Statistical Notes for Health Planners: Mortality . Public Health Service, Health Resources Administration, (HRA) 77-1237, U.S. Government Printing Office, Rockville, Maryland, February 1977. 7. Lalondt, M.A. A New Perspective on the Health of Canadians . Government of Canada, Ottawa, 1974. R. North Carolina Department of Human Resources, Division of Health Services, Public Health Statistics Branch. "Associations Between Mortality and Various Social, Economic, and Environmental Factors in North Carolina," PHSB Studies . No. 3, Raleigh, April 1977. 9. Milio, N. "An Ecological Approach to Health Planning for Illness Prevention," American Journal of Health Planning . Number 2, 1977. 10. North Carolina Department of Human Resources, Division of Health Services, Public Health Statistics Branch. "Health Characteristics of Adults in North Carolina," PHSB Studies . Number 11, Raleigh, N.C, July 1978. 11. Waldror , I. "Why Do Women Live Longer Than Men?," Social Science and Medicine. Volume 10, 1976, pp. 349-362. 1-28 12. Syme, S.L. ; Berkman, L.F. "Social Class, Susceptibility, and Sickness," American Journal_ of Epidemiology . Volume 104, Number 1, 1976, pp. 1-8. 13. North Carolina Department of Human Resources, Division of Health Services, Public Health Statistics. North Carolina Vital Statistics : Quarterly Provisional Report . January-March, 1978. Raleigh, N.C. 14. McKeown, T. ; Brown, R.G. "Medical Evidence Related to English Population Changes in the Eighteenth Century," Population Studies . Number 9, 1955, pp. 119-141. 15. Newsweek , June 19, 1978; see also Cassel, E. Human Ecology and Public Health . Kibourne and Smillie Editors, 1969, p. 353. 16. Office of State Budget and Management, Research Section. "Life Table For The Total Population, and White Male, White Female, Other Than White Male, and Other Than White Female Populations, North Carolina, 1979-80." Raleigh, N.C., 1981. 17. Paffenbarger, R.S.; Brand, R.J.; Sholtz, R.I.; Jung, D.L. "Energy Expenditure, Cigarette Smoking, and Blood Pressure Level as Related to Death from Specific Diseases," American Journal of Epidemiology . Volume 108, Number 1, 1978, pp. 12-18. 18. Eyer, J. "A Diet/Stress Interaction Hypothesis of Coronary Heart Disease EDidemiology," International Journal of Health Services . Volume 9, Number 1, 1979, pp. 161-168. 19. Doll, R. "The Smoking Induced Epidemic," Canadian Journal of Public Health . Volume 72, November/December 1981, pp. 372-381. 20. Curtiss, J.; Grahn, R.B.; Grahn, D. "Population Characteristics and Environmental Factors That Influence Level and Cause of Mortality: A Review," Journal of Environmental Pathology and Toxicology . Volume 4, Number 2, 1980, pp. 47l-Sll. 21. Doll, R. ; Peto, R. "The Causes of Cancer: Quantitative Estimates of Avoidable Risks of Cancer in the U.S. Today," Journal of the National Cancer Institute, 1981 (in press) . 22. U.S. Department of Health and Human Services, Office on Smoking and Health. The Health Consequences of Smoking: Cancer, a Report of the Surgeon General . Rockville, Md., 1982. 23. Walker, A.R. "Dietary Goals, Sensible Eating, and Nutrition in the Future," South African Medical Journal . Volume 57, Number 4, 1980, pp. 471-511. 24. Schmidt, W. ; Popham, R.E. "Heavy Alcohol Consumption and Physican Health Problems: A Review of the Epidemiological Evidence," Drug and Alcohol Dependence . Volume 1, Number 1, 1975, pp. 27-50. 1-29 25. Dyer, A.R.; et.al. "Alcohol Consumption, Cardiovascular Risk Factors, and Mortality in two Chicago Epidemiologic Studies," Circulation . Volume 56, Number 6, December 1977, pp. 1067-1074. 26. Tsuang, M.T. ; Woolson, R.F. "Mortality in Patients With Schizophrenia, Mania, Depression, and Surgical Conditions: A Comparison with General Population Mortality," British Journal of Psychiatry . Volume 130, 1977, pp. 162-166. 27. Egbuonu, L. "Child Health and Social Status," Pediatrics . Volume 69, Number 5, 1982, pp. 550-557. 28. Nathansen, C.A. "Sex, Illness, and Medical Care," Social Science and Medicine . Volume 11, 1977, pp. 13-15. 29. Madigan, F. "Are Sex Mortality Differentials Biologically Caused?" Milbank Memorial Fund Quarterly . Volume 35, 1957, pp. 202-223. 30. Verbrugge, L.M. "Recent Trends in Sex Mortality Differentials in the United States," Women and Health. Volume 5, Number 3, 1980, pp. 17-37. 1-30 II. Technical Notes CHANGES IN THE CAUSE-OF-DEATH CLASSIFICATION SYSTEM About every 10 years since 1900, what is now the International Classification of Diseases (ICD) has been revised in order to incorporate the latest state-of-the-art in disease classification. Each revision produces some break in the comparability of cause-of-death statistics, and the Ninth Revision—first applied to 1979 deaths—is no exception. The most serious breaks in comparability occurred with the following causes: pneumonia/influenza, chronic obstructive pulmonary disease, hypertension, atherosclerosis, other ischemic heart disease, and nephritis/nephrosis. In order to interpret mortality trends, the National Center for Health Statistics provided national estimates of the discontinuity associated with the change from the 8th to the 9th ICD, commonly referred to as "comparability ratios." These ratios for selected causes of death are found in the 1979 Leading Causes of Mortality . Also in the 1979 volume are a description of the method used to construct comparability ratios and an evaluation of these ratios using North Carolina data. Throughout this volume, comparability ratios are applied to pre-1979 rates for each cause listed above in order to make comparisons with 1979-81 rates. Yet, because these ratios are national estimates and are based on 1976 deaths, the reader is cautioned that the magnitude of the error associated with the corrected pre-1979 rates is unknown. Thus, for some causes and/or counties any revised pre-1979 rate could be significantly different from the "true" rate, thereby causing substantial changes in the trend of rates over time. 2-3 CHANGES IN POPULATION BASES DUE TO THE 1980 CENSUS As described in the previous section, the change in the disease classification system from 1978 to 1979 was one source of discontinuity in mortality rates over time. A second source was a change in population estimates. Every ten years (years ending in zero) the United States Bureau of the Census has conducted a count of the United States population, which includes a profile of the population's characteristics such as age, race, and sex. After a census year, estimates of population size and composition are based on knowledge of the population in the census year plus subsequent events such as births, deaths, and migration. In the later years of a decade, these estimates may depart considerably from the "true" population values if the assumptions about population change differ significantly from what actually occurred. Since almost all mortality rates in SCHS publications are based on population counts in the denominator, changes in estimates of population such ^s might result from a new census could cause substantial changes in the trend of rates over time. To complicate the problem even further, it is generally acknowledged that there was an undercount of the population of North Carolina in the 1970 census, particularly among nonwhites. Thus projections for the latter seventies tended to be low, and rates based on these population projections were correspondingly high. The 1980 Leading Causes of Mortality provided a detailed assessment of the effects of using the 1980 census figures versus 1980 population projections as the denominators of rates. 2-4 In this volume the reader should note that all pre-1980 rates have been corrected for changes in population bases in order to interpret trends. Tlnese corrected rates may differ from the rates shown in previous SCHS publications. 2-5 MORTALITY RATES Computation of Mortality Rates In this report, total death rates are expressed as resident deaths per 1,000 population while all cause-specific mortality rates are expressed as resident deaths per 100,000 population. All rates in Tables 1-27 use total population in the denominator, except rates for the sex-specific cancer sites, which use male or female population in the denominator. The infant mortality rates of Table 28 and Figure 28 are computed as the number of resident deaths under one year of aqe per 1,000 resident live births. Population bases for the rates of this report were provided by the Office of State Budget and Management in the Governor's Office. Vital events in this report are allocated to place of residence. For ri^aths of inmates of long-term institutions (mental, penal, old age, orphan, nursing home, rest home, etc.) , the institution is considered the usual residence provided the decedent had resided in the institution at least one year. College students and military personnel are considered residents of the college or military community. The following definitions apply to the rates of Tables 1-27: Unadjusted Annual Death Rate : the annual death rate computed as resident deaths per 1,000 or 100,000 population. These rates permit the user knowledge of an area's status with respect to the observed incidence of mortality during the given year. Unadjusted 3-Year Death Rate : the average annual death rate computed as average resident deaths per 1,000 or 100,000 average population. These rates permit the user knowledge of an area's status with respect to the observed incidence of mortality during the 3-year period. These rates are depicted in the Series A maps (e.g., Figures 2. A, 3. A, etc.). 2-6 Adjusted 3-Year Death Rate : the averaqe annual aqe- race-sex-ad justed rate, computed by the direct method. Also expressed as deaths per 1,000 or 100,000 population, these rates are those which would be expected if the average annual age, race, and sex composition of each county's population were the same as that estimated for the state. These rates are free of differing effects of age, race, and sex and thus permit the user knowledge of an area's status with respect to other determinants of mortality during the 3-year period. However, the user should be cautious when comparing an adjusted death rate with an unadjusted death rate. Also, adjusted rates for different time periods cannot be directly compared unless they were adjusted by the same standard population. The adjusted rates are depicted in the Series B maps (e.g., Figures 2.B, 3.B, etc.). These adjusted rates are based on a breakout of ten age groups for four race-sex groups, for a total of 40 age-race-sex "cells." In 1978 and earlier editions of Leading Causes of Mortality , adjusted rates were based on 18 age categories (72 cells) , and the change here to a smaller number of age categories is in keeping with the procedures of the National Center for Health Statistics. Interpretation of Mortality Rates To assess an area's relative mortality conditions during a three-year period, both the unadjusted rate and the adjusted rate can be compared to the state rate for a particular cause of death. Then, provided the area's unadjusted rate represents a relatively stable situation, viz., the rate has not fluctuated widely in recent years, the following alternative diagnoses will apply: Relative Status of Unadjusted Rate Low Low Adjusted Rate Low High Diagnosis Low mortality is not due to age, race, and sex factors; other mortality conditions are favorable. Low mortality is due to favorable age, race, and sex factors; other mortality conditions are unfavorable. 2-7 High Hiqh Low Hiqh High mortality is due to unfavorable age, race, and sex factors; other mortality conditions are favorable. High mortality is not due to age, race, and sex factors; other mortality conditions are unfavorable. In using adjusted rates, it is important that the user understand the reason for adjustment. The following hypothetical example illustrates. Here, A & B stand for population subgroups, e.g., whites and nonwhites, males and females, etc. County Death Population Deaths Rate* State Death Population Deaths Rate* Population A Population B Total 300,000 10,000 310,000 1,000 333.3 10 100.0 1,010 325.8 500,000 800,000 1,300,000 2,500 500.0 1,000 125.0 3,500 269.2 *Deaths per 100,000 population. Compared to the state, county subgroups A & B both have lower rates, but the county as a whole (A & B combined) has a higher rate. This seemingly paradoxical situation results from two factors: different proportions of A & B in the county vs. the state population and wide differences between the rates for A vs. B. In this example, it is true that the county has the higher total rate—BUT ONLY BECAUSE THE POPULATION CONTAINS A HIGH PROPORTION OF SUBGROUP A. Certainly, it is important for program planners to know that the county has a high rate relative to the state rate; this information is needed in determining manpower and facility needs, etc. But in assessing "risk," the researcher needs to adjust for confounding factors such as age or race. To do this, one multiplies each population-specific county rate by the corresponding 2-1 "standard" population, sums these results, and divides by the total "standard." In the above example, using the state population as the standard, the computation is: ( 1000 x 500,000) + ( 10 x 800,000) 300,000 10,000 = 0.001897 or 189.7 per 1,300,000 100,000 population Thus, as rates specific for A & B imply, the county's rate is lower than the state rate after adjustment for the factor represented by A & B. Caution ! In assessing the relative mortality conditions of a county, one should be particularly aware of rates based on a small number of deaths since, in such cases, random fluctuation in the rate may render rate comparisons risky. The reader should read very carefully the next section entitled Flagging Biased Rates. Flagging Biased Rates This section discusses the problem of unstable mortality rates and then goes on to describe a method of flagging rates with a large bias in a given year. The reason for flagging an unstable or possibly biased rate is to provide the reader with a criterion for placing confidence in statements, tables, maps, and other interpretive displays of the mortality data. Not all calculated rates are an accurate portrayal of the underlying or "true" force of mortality, and the intent of this section is to caution the reader against uncritically using the rates in this volume. In the maps in particular, the reader should be alert to unusually high rates that may result from very small numerators or from the type of bias described below. Any rate with a small number of events in the numerator will be unstable, with possibly large random fluctuations from year to year that do not comprise 2-9 a significant trend. Such a rate is said to have a large standard error . A useful rule is that any rate based on fewer than 20 events (deaths in this volume) in the numerator may have a 95 percent confidence interval that is wider than the rate itself (1). For example, in an area with 20 deaths out of 20,000 population, the measured rate would be 100 deaths per 100,000 population. But due to variability over time in rates with small numerators, one could say with 95 percent certainty only that the underlying or "true" rate is between approximately 50 and 150 per 100,000. Many of the rates in this volume have numerators smaller than 20 and thus a large standard error, and therefore conclusions about trends based on these rates should be made very cautiously, or not at all. The age- race-sex-ad justed rates in this volume, described in the previous section, are likewise subject to random variability over time, and those rates involving a small number of deaths will be the most unstable. Computation of a standard error for these rates is more complex than for the unadjusted rates, and depends on the sizes of both the numerators and denominators in each of the age-race-sex-specific cells. Counties with a small number of persons in one or more of the 40 age-race-sex groups are, however, most likely to have adjusted rates with a large standard error, and the rates will therefore show substantial random fluctuation over time. Table C lists 13 counties whose adjusted rates are likely to have a large standard error due to 10 or fewer persons in one or more of the age-race-sex groups in 1980. All of these counties had less than 1000 nonwhites in 1980 and it is generally the nonwhite, age 85-and-over race-age group that has the small number of persons. The adjusted rates in these counties in particular may change substantially from one year to the next just due to random error. 2-10 TABLE C Counties with Small Age-Race-Sex Fbpu]atior. Groups that are Hke]y to have Adjusted Death Rates with Large Standard Errors Alleghany Haywood Ashe Macon Avery Madison Cherokee Mitchell Q ay Watauga Dare Yancey Graham In addition to the problem of potential random variation in rates due to a large standard error, there is the problem of bias in an adjusted rate in a given year due to one or more deaths in a small population group. For example, it has happened that one death occurs in an age-race-sex group where the estimated population is only ore person, and this results in a rate of 100,000 deaths per 100,000 population. Of course this is not the "true" rate in that population group, and the "expected" number of deaths per year is much less than one, but such an occurrerce can result in an extremely biased adjusted rate. Applying the rate of 100,000 to the appropriate age-race-sex cell of the standard population, by the direct method of adjustment, will result in an expectation of 100 percent of that group dying and thus a very large adjusted rate. In the past no systematic method existed for "flagging" these biased rates in Leading Causes of Mortality . For the first time in this volume, rates with a possibly large bias of this sort are flagged with an asterisk. Rates with a large standard error have not yet been flagged, though counties likely to have such rates are identified in Table C. Factors considered in flagging the 1979-81 age-race-sex- adjusted rates were: 1) the ratio of the number of expected deaths, in any one of the 40 age-race-sex cells of the standard population to the total 2-11 expected deaths and 2) the size of the denominator of the eel ] -specific rates. If applying the ce] 1 -specif ic rates of a county to the standard population results in more than 25 percent of the total expected deaths being generated by ore cell, then that adjusted rate is flagged if the denominator of the rate is also less than 30 (or an average of 10 per year). Ihese criteria result in only 23 out of a total of 2500 county rates in this volume, or about ore percent, being flagged. The 25 percent criterion for one cell was higher than what would be expected for any of the causes. Ir. fact, this could probably be reduced somewhat. For 1980 North Carolina total deaths, the highest percent of deaths accounted for by any ore of the 40 age- race-sex cells was 9.7 by white females age 75-84. Nonwhite males age 25-14 accounted for 17.5 percent of all 1980 homicide deaths. Ihe cut-off of fewer than 30 persons ir the denominator (an average of 10 per year for 3 years) was a somewhat arbitrary choice, but a populatior limit was desirable in order to reduce the chances of flagging an adjusted rate where a high age- race-sex-specific cell rate was due to an actual epidemic or disaster. Ihus one death in the problem cell of a flagged rate would result in a eel 1 -specif ic rate of at least 1/29, or 3448 out of 100,000. For North Carolina as a VNhole in 1979-81, only the total heart disease rate for the age 85+ group was higher than this, and most of the age-race- sex-sp..-ci fie rates are very much lower. We experimented with other combinations of the two criteria, and the r umbers of rates flagged for six different combirations are shown below. Doubling the denominator cutoff to ^0 and lowering the percentage of expected deaths from 25 to 20 triples the rumb^r of flagged rates to 70. While only 23 rates are flagged in this volume, it is felt that most of the flagrant biases 2-12 have been identified. Work will continue to evaluate and enhance this methodology. Number of Flagged Rates Based On Denominator Size and Percent of Total Expected Deaths Denominator Size Less Than 30 45 60 Percent of Total Expected Deaths Accounted for by One Cell Greater Than 20% 50% 31 51 70 23 38 51 In addition to putting asterisks by those 1979-81 adjusted rates with a large bias due to an extremely high cell-specific rate, the rates have been recomputed by substituting the appropriate North Carolina age-race-sex-specific rate in the problem cell. Table D compares the flagged rates with the recomputed rates. In a very extreme case, like the Clay County homicide rate, substituting the N.C. age-race-sex-specific rate produces a much more reasonable adjusted rate by reducing the rate from 126.4 to 7.0, the latter being much more in line with the state homicide rate for 1979-81 of 11.1. In a few cases, substituting the state rate makes the county's adjusted rate much smaller than the state figure, which also illustrates the volatility of death rates based on just a few events. The reader who must use one of these flagged rates is advised to use the rate in Table D with the substitution instead, unless this latter rate is clearly out of line with the North Carolina rate in which case the rate should be treated as missing data. 2-13 u PROCEDURE FOR GEOGRAPHIC CLUSTERING OF COUNTIES In previous editions of this report, county rates for each leading cause of mortality have been mapped. As described in the Introduction of this volume, these maps showed counties grouped together (usually in six groups) based on similar rates—in other words, a numerical clustering of rates. From these maps, one might imply "spatial" clustering if counties with high rates happened to be contiguous to each other. However, under this procedure there is no way to know whether this clustering is a "true" geographic cluster or an artifact of the SAS clustering procedure (2). In 1980 the State Center for Health Statistics in conjunction with the UNC Department of Biostatistics developed a new statistical procedure for detecting and characterizing spatial clusters. This procedure determines statistically whether counties with high rates are clustering on some geographic basis. Only a brief summary of the mechanics of the procedure is presented in this section. For a detailed description, interested readers are advised to read "Searching for Hierarchical Clusters of Disease: Spatial Patterns of Sudden Infant Death Syndrome" in Social Science Medicine , Vol. 15D, pp. 287-293 or contact the State Center for Health Statistics. Briefly the mechanics of this procedure are as follows: (1) Counties are listed in rank order of their unadjusted or adjusted rates (highest rates first) for each cause of death. (2) For each county listed, cumulative counts are obtained of the number of counties and the number of adjacencies involved between the county and those counties with higher rates. Two counties are 2-15 considered adjacent if they have a common nonsalt-water boundary. For some "pairs" of counties (in particular, counties which seem to touch only at one point on a map) , it was difficult to decide whether these counties are adjacent. These "troublesome pairs of counties" in North Carolina are discussed in the above paper as are the decisions made with regard to these pairs. (3) Finally, a reference table developed in the above paper is used to obtain for the cumulative number of high-rate counties a significance level based on the number of adjacencies observed. While a few adjacencies might be expected to occur randomly, a relatively large number of adjacencies will have a low probability of random occurrence. In this report, the high-rate counties are said to cluster geographically if the probability of such random occurrence is .05 or less; maps for a given disease are included in the text only if statistically significant geographic clusters were found to exist. This procedure can result in one or more groups of contiguous high-rate counties. This concept is referred to as regional ization, defined here as any area of the state consisting of two or more contiguous counties being identified as a high-risk area. For some diseases, no regional ization of this type exists. For some others it does, and for yet others two or more regions exist. In the latter case, a disease may regionalize with high rates in one part of the state and with other tiers or levels of high rates in some other parts of the state. In this report each map shows the multi-tiers or levels via different shading schemes. 2-16 This method is a simple and inexpensive approach for recognizing mortality patterns of varying intensity in geographical areas and for testing for clusters. Further refinements of the procedure are in the planning stage. 2-17 REFERENCES FOR SECTION II 1. Kleinman, J.C. "Infant Mortality," Statistical Notes for Health Planners . Number 2, National Center for Health Statistics, Rockville, Maryland, July 1976. 2. SAS Institute Inc. SAS User's Guide: Statistics, 1982 Edition , Cluster Procedure. Cary, N. C. , 1982. 2-18 North Carolina's Population and Health Care Resources NORTH CAROLINA'S POPULATION AND HEALTH CARE RESOURCES As stated ir the 1976 edition of this volume (1): Equal access to health care is a basic right of all citizens, but to date, this right has been precluded in North Carol ina by such interrelated deterrents as poverty, rural ity, and maldistribution of health care resources. The ensuing years have brought progress but the old problems still persist. Heart disease, career, stroke, and accidents continue to be the leading causes of death. Although declining, North Carolina's infant mortality rate cortinues to be ranked amorg the highest in the 50 states. Compounding these problems is a rapidly aging North Carolina population which has served to minimize decreases in mortality. To combat these problems, significant strides have been made to improve the availability of health care resources. The numbers of physicians, nurses, ar d hospital ard nursing home beds have increased. Services of primary care physiciars have been augmented with the ir.creased use of physiciar assistants and rurse pr actitior.ers. But despite these ard other recent improvements, North Carolina still ranks behind most other states in the availability of most types of health manpower and facilities (2). From this assessment, ore fact appears to be quite evident. That is, neither the problems nor the resources are evenly distributed in North Carolina. Too oftrj r the problems occur where the resources are scarce. While this sectior will rot undertake a detailed analysis of health care resources ir each county, it will examine the levels of selected health manpower and facilities across the state. Hopefully, these data will aid health officials and others in planning for improved health conditions throughout the state. 3-3 County Populations Underscoring the state's need to improve the availability and distribution of health care resources, increasing size and changing composition of North Carolina's population are altering the disease and mortality proneness of various geographical areas. Between 1976 and 1981, North Carolina's population increased an estimated o.5 percent, with nonwhites experiencing an 8.6 percent increase. Of prime importance here is the rapidly riging North Carolina population. During the past 5 years, persons 65 and over increased by 17.8 percent, a pace faster than that for the United States as a whole. While the state's population as a whole is projected to increase only 7 percent by 1986, the state's elderly population is expected to increase another 17.8 percent. Further, persons 75 and older are projected to increase by 27 percent in the next five years, a pace faster than that of any other age group. While detailed analysis of each county's population is beyond the scope of this volume, county populations have been compared to the state population with respect to four demographic characteristics—percent rural, percent over 64 years of age, percent nonwhite, and percent with income below the poverty level. In the 1976 edition of this volume, 31 counties were found to be above the state rate on all four characteristics. When the same comparison was done with 1980 data, 30 counties were above the state, including 26 of those in 1976. As before, these demographically high-risk counties comprise fairly well-defined geographical pockets in central and eastern North Carolina: 3-4 Anson other eastern counties—Chowan, Pasquotank, Dare, and New Hanover—which have relatively low ratios (Level 1). Physicians in these latter counties may well be providing primary care services to surrounding counties. Among the counties with level-four to level-six ratios, four—Bertie, Camden, Gates, and Perquimans—have both a demographically high-risk population (see page 3-4) and high mortality (See Figure 2.A) . Two of these counties (Camden and Perquimans) have only one primary care physician and one (Gates) has none. County Population Per Primary Care Physician, Physician Assistant, and Nurse Practitioner In North Carolina there has been a recent increase in the use of physician assistants and nurse practitioners. Variously referred to as health practitioners, physician extenders, or mid-level practitioners, these professionals can perform certain defined medical tasks previously done by physicians; however, they can perform these tasks only under a physician's supervision. Yet, their impact on the level of primary care services available in North Carolina requires that these professionals be considered for the first time in this volume. During 1981 a total of 762 physician assistants and nurse practitioners provided primary care services in 87 counties. Because of the number and distribution of these professionals, it is desirable to show their effect on the potential case load of primary care physicians. One approach involves treating these practitioners as some proportion of a fulltime primary care physician, thereby reflecting the proportion of physician's work that the practitioner may perform. A recent study suggested 63 percent as a "good middle-of-the-road estimate" (3). Using this percent, every 100 physician 3-6 assistants and nurse practitioners will be equivalent (ir terms of work load) to 63 full time physicians. The number of practitiorers obtained using this procedure will hereafter be referred to as "physician equivalents." For North Carol ina , the population-per-pr imary-care-physician-and-physiciar -equivalent ratio is 1570. figure l.B shows the county population per primary care physician and physician equivalent in 1981. The use of this ratio changes substantially the picture of primary care services available in some counties, especially a few of the high-ratio counties identified in Figure l.A. For example, in Greene County, the popul ation-per-physician (1 physician) ratio is 16,078 but the popul ation-per-physician/physician-equivalent (1 physician, 4 nurse practitioners, and 2 physician assistants) ratio is 3,364, a 79.1 percent decrease in potential case load. Ir: Hoke County the respective ratios are 7,067 (3 physicians) and 4,336 (3 physicians and 3 physician assistants). Gates was the only county without a primary care physician and thus had no physiciar assistants or nurse practitioners. Cotrties with high ratios (Levels 5 and 6) in both Figures l.A and l.B should be priority areas for recruitment of primary care services. Among these counties, four—Bertie, Camder , Gates, and Perquimans—appear in particular need of additional services because they have demographically high-risk populations (see page 3- 4), have high mortality rates (Levels 4-6), and have popul at ion/physician-equivalent ratios over 2.5 times the North Carolina ratio of 1,570. County Fbpulation Per Registered Nurse The ratios of Figure l.C are the county populations per registered nurse working in the county and licensed to practice in North Carolina as of March 1, 1981. As expected, counties with high population/nurse ratios are largely 3-7 those with high population/physician ratios (Figure l.A) . Q,e exception is Graham County with a very high population/nurse ratio but a relatively low population/physician ratio. As discussed for physicians, county needs for registered r.urses must take into account the characteristics of county populations. In Figure l.C, the 11 counties with population/nurse ratios at levels 4-6 include six counties — Currituck, Franklin, Hyde, Northampton, Pamlico, and Warren—which are demographicall y high-risk according to criteria described on page 3-4 and are unusual ly mortal ity-prone (Levels 4-6) as depicted in Figure 2. A. County Population Per Hospital Bed Short-term general hospitals provide a broad range of medical and surgical services to patients whose average hospital stay is Jess than 30 days. The ratios of Figure I.Dare the county populations per patient bed in short-term general hospitals licensed by the North Carolina Division of Facility Services as of December 31, 1981. As explained for physicians, federal hospitals are not included but county populations include members of the armed forces; thus, ratios are biased upward for counties with large military populations (i.e., Craven, Cumberland, Q-.slow, and Wayne counties). As show, in Figure l.D, seventeen North Carolina counties have no short-term general hospitals (level six) and another ten have high population/bed ratios (Levels 4 and 5). Among these counties, three (Camden, Gates, and Perquimans) are also demographicall y high-risk according to the criteria given or page 3-4, have high mortality rates as show, in Figure 2. A, and have high populatior-per-physician/physician-equivalent ratios. The popul ation-per-bed ratio for North Carolina is 270. 3-8 Even more so than in the case of physicians, hospitals in certain larger counties will provide services to the residents of surrounding counties. Therefore a high ratio for a county does not necessarily mean that its residents are not receiving hospital services. It is not feasible for every N.C. county to have a hospital, and regional ization of some services is indeed desirable. County Population 75+ per Skilled Nursing and Intermediate Care Beds Two levels of nursing homes exist in North Carolina—skilled nursing facilities and intermediate care facilities. Skilled nursing facilities provide continuous medical supervision to patients for management of chronic conditions. Intermediate care facilities provide health- related care and services to individuals who do not require the degree of care or treatment which a hospital or skilled nursing facility is designed to provide. Many nursing homes offer both levels of care. (4) The growth of nursing homes and nursing home beds over the past decade has been tremendous. In 1970 there were 108 homes containing 6,809 beds for skilled and intermediate care. By 1981 the number of facilities had increased to 205 and the number of beds to 19,824, a near doubling of facilities and tripling of beds. The number of primary users of these beds has increased rapidly also. In this volume, "users" are defined as persons over age 74 due to the fact that this age group comprised 71 percent of all admissions to nursing homes in 1980-81. Between 1970 and 1981, the 75-and-older population increased 61 percent and, as noted previously, is projected to increase another 27 percent by 1986 (5). Yet, while the elderly population continues to grow, the facility and bed growths have essentially stopped with the current moratorium on the approval of new nursing home beds. 3-9 Figure l.E shows the distribution of population-per-skilled-and-intprmedi a te-ca re-bed ratios for each county. As exemplified in previous imps, an uneven distribution exists among counties with the same eastern high-risk counties having the fewest beds. Several contiguous counties in the northeast corner of the state have no beds, but in the midst of these counties, two—Chowan (4.7) and Pasquotank (5.4) —have exceedingly low ratios in contrast to the state as a whole (11.0 persons 75+ per bed). This suggests that facilities in these two counties may be serving persons from surrounding counties. In fact, among the 21 counties with no beds, almost all have a neighboring county with a low ratio (i.e., less than 10.0). 3-10 CE CC _l ~ZL GZ _J CO LU CO CC Q LU CC LU h- CO i— i CD LU CC UJ CC CO u. EGO 3-15 ac CC CO CD LU 0Q a: Q_ CO o oc CD cc cc CD DZ CO _l ce -Z. CE CO LU CQ CD CO CC cc CE C_J LU CE i— i Q LU 11 CC LU ~3 CD CO _J REFERENCES FOR SECTION III 1. North Caroling Department of Human Resources, Division of Health Services, State Center for Health Statistics. Leading Causes of Mortality - Volume II . Raleigh, December 1977. 2. North Carolina Department of Human Resources, Division of Health Services, State Center for Health Statistics. N.C. Health Statistics Pocket Guide . Raleigh, February, 1982. 3. Perry, H.B.; Breitner, B. Physician Assistants: Their Contribution to Health Care . Human Sciences Press, Inc., New York, 1982. 4. North Carolina Department of Human Resources, Division of Facility Services, State Health Planning Section. State Medical Facilities Plan 1983 . Raleigh, January 1983. 5. Office of State Budget and Management, Research and Planning Section. Update: North Carolina Population Projections . Raleigh, N. C, July, 1981. 3-21 IV. General Mortality in North Carolina GENERAL MORTALITY IN NORTH CAROLINA During 1981 a total of 49,212 North Carolinians died. This number represents an annual death rate of 8.3 resident deaths per 1,000 population, 5.7 percent below the rate of 8.8 in 1970 but almost equal to the corrected (for reasons described in Section II) rate of 8.2 in 1976. The provisional 1981 rate for the United States was higher at 8.7 (1). One confounding factor in making comparisons of mortality rates is that age structure, which has an important effect on mortality, may vary among geographic areas and over time. Compared to the nation, North Carolina has a younger but more rapidly aging population. Thus, adjusting the North Carolina and United States mortality rates for age, a higher mortality rate is obtained for N.C. (6.1) than the U.S. (5.7) for 1981, illustrating that N.C. 's lower unadjusted rate is due to its favorable age structure (i.e., more people at the young low-risk ages) . The "bottoming-out" of the unadjusted rates in the seventies suggests also that the N.C. population is aging. While the N.C. trend for unadjusted rates indicates virtually no change in mortality, examination of adjusted rates shows a different pattern. From the 1974-78 to the 1979-81 period (periods in which comparable age-adjusted rates were readily available), the risk of death for North Carolinians actually declined by 7.9 percent from 668.2 to 615.6 per 100,000 population. Yet, within the above general comparisons of mortality, significant subgroup differences are concealed, especially between N.C. and the U.S. For example, while the unadjusted U.S. rate was higher than that for North Carolina, each of the ten-year age groups between ages 35 and 64 in North 4-3 Carolina had age-specific rates at least 10 percent higher than comparable United States groups. The other North Carolina age groups with higher rates were the 0-4 age group (8.3% higher), the 5-14 group (1.6% higher), and the 65-74 group (4.4% higher). The 15-24, 25-34 and 85+ N.C. age groups had lower rates than their U.S. counterparts. As observed with age, general comparisons can mask variations by race and sex. Looking at North Carolina deaths in the 1979-81 period, the nonwhite rate (840.5 per 100,000 population) exceeded the white rate (808.8) by only 3.9 percent, but the male rate (948.4) exceeded the female rate (692.0) by 37.1 percent. Yet, even those comparisons mask the exceedingly high overall mortality rate for nonwhite males. Adjusting the race-sex-specific rates for age using a relatively young 1940 U.S. population as the standard, the adjusted rate was lower than the unadjusted rate for each race-sex group except nonwhite males, who had a higher death rate after adjustment (1010.8 vs. 1126.0). This higher rate implies that nonwhite males are dying at younger ages than any other race-sex group, a fact also revealed through the age-specific rates. With the exception of the 15-24 and 85+ age groups, nonwhite males had the highest age-specific mortality rates of the four race-sex groups. In each of the ten-year age groups between ages 25 and 54, the rates for nonwhite males were at least twice those for any other group. In Sections V through X, the varying risks of mortality by age, race, and sex groups will be discussed for each cause. Geographic Patterns The 1979-81 unadjusted mortality rates for counties, depicted in Figure 2. A, ranged from 3.8 per 1,000 population to 12.8, with a N.C. rate of 8.3 for the period. In general, Figure 2. A shows several scattered groups of high- 4-4 rate counties, with the northeast seemingly having the largest cluster. In most cases, these high rates reflect unfavorable mortality conditions other than age, race, and sex since among the 23 counties with level-five or higher unadjusted rates (Figure 2. A) , 18 had level-four or higher adjusted rates (Figure 2.B) . In addition, Figure 2.B shows a large eastern band of contiguous, high-rate counties (levels 5-6) extending from Virginia to South Carolina and eastward to the Atlantic Ocean. Based on procedures described in Section II of this volume, the clustering of high unadjusted county rates in the northeast was found to be statistically significant (see map below) . In fact, two separate northeastern clusters were found to exist: one group involving seven counties centered around Halifax and Warren counties, and a second group with high but lesser rates consisting of Beaufort, Hyde, and Tyrrell counties. These 10 counties are among the top 12 counties experiencing the highest mortality rates in the 1979-81 period. A third distinct cluster exists in the west with Polk, which had the highest of all county rates, as the base. GENERAL MORTALITY MORTALITY RRTES PER 1,000 POPULATION 10.6 - 12.8 (p <.001) ES 9.7 - 10.5 (p=.043) D 0.0 - 9.6 NORTH CAROLINA RESIDENT DATA 1979 - 1981 4-5 The clustering of high adjusted rates in the east was also found to be statistically significant (see map below) . Unlike the unadjusted rates, no significant clusters of high adjusted rates exist in the west. Thus, eastern North Carolina is experiencing high levels of general mortality that cannot be explained on the basis of age, race, and sex alone. In these cases, high mortality may be due to socioeconomic and resource factors (see discussion of health care resources in Section III) or to some other set of local conditions that invite intervention. The cause-specific data in the sections to follow will aid counties in identifying their particular kinds of mortality proneness. GENERAL MORTALITY RGE-RACE-SEX ADJUSTED MORTALITY RATES PER 1.000 POPULATION B 9.0 - 9.9 (p <.001) fg 8.7 - 8.9 (p <-001) 0.0 - 8.6 NORTH CAROLINA RESIDENT DATA 1979 - 1981 4-6 table: 2 mortality statistics for 19 8 1 north carolina residents total deaths (per loco population) GEOGRAPHICAL AREA f'ORTH CAROLINA REGIONS DHP DHR WESTERN N. CENTRAL DHR III S. CENTRAL DHR IV EASTERN HSA HSA HSA HSA HSA HSA I WESTERN II PIEDMONT III S. PIEDMONT IV CAPITAL V CARDINAL VI EASTERN COUNTIES 1 ALAMANCE 2 ALEXANDER 3 ALLEGHANY 4 ANSON 5 ASHE 6 AVERY 7 BEAUFORT 8 BERTIE 9 BLADEN 10 BRUNSWICK 11 BUNCOMBE 12 BURKE 13 CABARRUS 14 CALDWELL 15 CAMDEN 16 CARTERET 17 CASWELL 18 CATAWBA 19 CHATHAM 20 CHEROKEE 21 CHOWAN 22 CLAY 23 CLEVELAND 24 COLUMBUS 25 CRAVEN 26 CUMBERLAND 27 CURRITUCK 26 DARE 29 DAVIDSON 30 DAVIE 31 OUFLIf>' 32 DURHA" 33 EDGECOMBE 34 FORSYTH 35 FRANKLIN 36 GASTON 37 GATES 3B GRAHA* 39 GRANVILLE 40 GREENF 41 GUILFORD * SEE SECTION II NUMBER MORTALITY STATISTICS FOR 1961, NORTH CAROLINA RESIDENTS TOTAL DEATHS (PER 1000 POPULATION) CONT'D. COUNTIES (CONT'O) 42 HALIFAX 43 HARNETT 44 HAYWOOD 45 HENDERSON 46 HERTFORD 47 HOKE 4e HYCE 49 IREDELL 50 JACKSON 51 JOHNSTON *2 JONES 53 LEE 54 LENOIP 55 LINCOLN 56 *CDOWFLL 57 MACON 5P "ADISON 59 MARTI" 60 MECKLENBURG 61 MITCHELL 62 MONTGOMERY 63 MOORE 64 r.'ASH 65 NEW HANOVER 66 NORTHAMPTON 67 ONSLOW 68 ORANGE 69 PAMLICO 70 PASCUOTANK 71 PENDER 72 PERCUIMANS 73 PERSON 74 PITT 75 POLK 76 RANDOLPH 77 RICHMOND 78 POPESCM 79 ROCKINGHAM 80 ROWAN 81 RUTHERFORD 82 SAMPSON 83 SCOTLAND 84 STANLY 85 STOKES 86 SURRY 87 SWAIN «8 TRANSYLVANIA 89 TYRRELL 90 UNION 91 VANCE 92 WAKE =>3 WARREN 04 WASHINGTON 95 WATAUGA 96 WAYNE 97 WILKES 98 WILSON 99 YADKIN 100 YANCEY NUMBER >- CE h-az CD cr az i_u LU CD > in m GOD 4-9 >- en i— cc CD cn cc LU CD LU cc CD 3 *- REFERENCE FOR SECTION IV United States Department of Health and Human Services, Public Health Service, National Center for Health Statistics. "Annual Summary of Births, Deaths, Carriages, and Divorces: United States 1981, "Monthly Vital Statistics Report . (PHS) 83-1120, Volume 30, Number 13, Hyattsville, Maryland, December 20, 1982. 4-13 V. Major Cardiovascular Disease Mortality HEART DISEASE Over 17 percent of deaths among North Carolina residents in 1981 resulted from heart disease, which has been the leading cause of death for the state and the nation for almost 50 years (1) . Diseases of the heart accounted for 18,270 deaths in the state in 1981, a rate of 306.5 per 100,000 population. While the 1981 provisional rate for the United States was higher at 330.6 (2), North Carolina's age-adjusted rate of 211.7 was 7.8 percent higher than the nation's (196.4). Almost 72 percent of the state's heart disease deaths were from ischemic heart disease in 1981. Of these deaths, acute myocardial infarction (heart attacks) accounted for 8,091 deaths while the other forms of ischemic heart disease accounted for 5,036 deaths. The death rate from diseases of the heart has declined in North Carolina, with the 1979-1981 age-adjusted rate of 211.9 representing an 8.4 percent decrease over the 1974-78 rate of 231.4. The largest decrease was among white males for whom the 1979-1981 age-adjusted rate was down over 11 percent at 301.2 as opposed to 338.9 for the 1974-1978 period. Age-adjusted rates for the other race-sex groups also declined and were as follows for 1979-1981 (with percent reduction): 128.0 for white females (6.4%), 333.3 for nonwhite males (2.6%), and 182.9 for nonwhite females (5.7%). Age-adjusted death rates decreased for both acute myocardial infarction and other types of ischemic heart disease for all four race-sex groups. 5-3 Risk Factors A number of factors are associated with an increased risk of heart disease. Among these are hypertension, atherosclerosis, high cholesterol, diabetes, cigarette smoking, increasing age, sex (men have higher mortality rates though the male and female rates tend to converge around the age of menopause), and a sedentary lifestyle (1,3-5). Although white males had the largest decrease in death rates from acute myocardial infarction between the 1974-1978 and 1979-1981 periods, they still die of heart attacks more than twice as often as they die of other ischemic heart disease. For males of all races, heart attacks caused more deaths than other forms of ischemic heart disease up to the 85-and-over age group. The same was true for white females, whereas nonwhite females 75-84 had a higher rate of death from other forms of ischemic heart disease than from heart attacks. North Carolina's decrease in heart disease death rates is consistent with declines nationwide (1,2). While it is difficult to pinpoint specific reasons for these decreases, awareness of the risk factors associated with heart disease has been heightened in the medical community and general population. As a result, people seem to be more conscious of diet and exercise, and the medical community has responded with earlier diagnosis and treatment of hypertension and other medically associated risk factors (1,4,5). Geographic Patterns Figure 3.A depicts mortality rates for diseases of the heart for 1979- 1981 and shows several contiguous, high-rate counties in the northeast, southcentral , and western portions the state. Adjusting for age, race, and sex, however, changes the distribution of heart disease mortality among North Carolina residents. As shown in Figure 3.B, the high-rate counties (Levels 4- 5-4 6) exist almost exclusively in the east. Based on the procedures described in Section II of this report, the map below reveals that of the 13 counties with the highest unadjusted rates, a statistically significant geographic cluster exists in the northeast. DISEASES OF THE HERRT MORTALITY RATES PER 100,000 POPULATION 13 395.2 - 487.0 (p° .021) 0.0 - 395.1 NORTH CAROLINA RESIDENT DATA 1979 - 1981 Adjusting for age, race, and sex, the clustering properties of county rates are stronger and are largely eastern (see map below) . The rare and rather large spatial grouping of 15 counties extends from Tyrrell to Halifax and south to Bladen. The interpretation here is that these contiguous counties are all experiencing higher levels of heart disease mortality than can be explained on the basis of age, race, and sex and that some regional factor is in operation. 5-5 DISEASES OF THE HEART AGE-RACE-SEX ADJUSTED MORTALITY RATES PER 100,000 POPULATION Eg 329.4 - 421.6 (p <.001) 0.0 - 329.3 NORTH CAROLINA RESIDENT DATA 1979 - 1981 The two major forms of heart disease (acute myocardial infarction and other types of ischemic heart disease) are examined separately in the following sections. 5-6 GEOGRAPHICAL ARE* T A B L E 3 MORTALITY STATISTICS FOR 1961 NORTH CAROLINA RESIDENTS DISEASES OF HEART NUMBER DEATH OF DEATHS RATE* 1979-61 1979-81 NUMBER MORTALITY STATISTICS FOR 1961. NORTH CAROLINA RESIDENTS DISEASES OF HEART CONT'D. COUNTIES ICONT'D) 42 HALIFAX 43 HARNETT 44 HAYWOOD 45 HENDERSON 46 HERTFORD 47 HOKE 48 HYDE 49 IREDELL 50 JACKSON 51 JOHNSTON 52 JONES 53 LEE 54 LENOI" 55 LINCOLN 56 MCDOWELL 57 MACON 58 MADISON 59 MARTIN 60 MECKLENBURG 61 MITCHELL 62 MONTGOMERY 63 MOORE 64 NASH 65 NEW HANOVER 66 NORTHAMPTON 67 ONSLOW 68 ORANGE 69 PAMLICO 70 PASOUOTANK 71 PENDER 72 PEROUIMANS 73 PERSON 74 PITT 75 POLK 76 RANDOLPH 77 RICHMOND 78 ROBESON 79 ROCKINGHAM 80 ROWAN 81 RUTHERFORD 82 SAMPSON 83 SCOTLAND 84 STANLY 85 STOKES 86 SURRY 87 SWAIN 88 TRANSYLVANIA 89 TYRRELL 90 UNION 91 VANCE 92 WAKE 93 WARREN 94 WASHINGTON 95 WATAUGA 96 WAYNE 97 WILKES 96 WILSON 99 YADKIN 100 YANCEY NUMBER az i_u LU CO LU CO CC LU CO i— i Q cr cn LU CC IS) J IT) !> CE _l ACUTE MYOCARDIAL INFARCTION An estimated 3,400 Americans suffer heart attacks each day. In 1981 over 292,000 of these attacks in the United States were fatal, a provisional rate of 127.5 deaths per 100,000 population (2). North Carolina's 1981 rate was higher at 135.7. Both the unadjusted and age-adjusted rates for acute myocardial infarction exceeded the corresponding United States rates. A total of 8,091 fatal heart attacks occurred to North Carolinians in 1981, and over 60 percent of those decedents were males. As shown by age-adjusted rates for the 1979-81 period, males had a much greater risk than females. White males had the highest rate (164.4), followed by nonwhite males (134.8), nonwhite females (61.7), and white females (56.9). The risk of death from acute myocardial infarction declined from the 1974-78 to the 1979-81 period for each race-sex group with white males experiencing the largest percent decline (19%) . Risk Factors As is the case with heart disease in general, the risk of fatal heart attacks is correlated with high cholesterol, cigarette smoking, sex (males have higher rates of heart attacks), and low levels of exercise (1,3-6). Also, hypertension and atherosclerosis are known to be related conditions (3,4) as indicated by the high number of mentions of these two conditions on death certificates that also mention acute myocardial infarction (see Table 31 in Section X) . Improvements in diagnosis and treatment of these conditions as well as decreased exposure to other risk factors and improved medical services (i.e., establishment of coronary care and intensive care units and better 5-13 training among emergency medical services personnel) have contributed to declines in fatal heart attacks (1,4). Geographic Patterns As shown in Figure 4. A, high rates (Levels 4-6) are dispersed throughout the state with three noticeable areas of high rates—the northeast, southeast, and southcentral areas of the state. Low rates are found in the northcentral and western portions. After adjusting for age, race, and sex, the clusters of counties with high rates persist, most notably in the southcentral and southeastern portions of the state. The western counties continue to have relatively low rates. Procedures described in Section II were used to test statistically whether the above contiguous areas with high unadjusted rates cluster geographically. As shown in the map below, four significant geographic clusters of high mortality from acute myocardial infarction exist; however, these clusters are not very strong, and when adjustments are made for age, race, and sex, no statistically significant clusters remain. ACUTE MYOCARDIAL INFARCTION MORTALITY RRTES PER 100.000 POPULATION B 179.8 - 263.4 (p-.043) 0.0 - 179.7 NORTH CAROLINA RESIDENT DATA 1979 - 1981 5-14 GEOGRAPHICAL AREA T A B L E it MORTALITY STATISTICS FOR 1961 NORTH CAROLINA RESIDENTS ACUTE MYOCARDIAL INFARCTION NUMBER DEATH NUMBER DEATH OF DEATHS RATE* OF DEATHS RATE* 1981 1961 1979-81 1979-81 NORTH CAROLINA REGIONS 8091 135. 74 24177 136.81 ADJUSTED DEATH RATE* 1979-81 136.61 DHR I WESTERN MORTALITY STATISTICS FOR 1981. NORTH CAROLINA RESIDENTS ACUTE MYOCARDIAL INFARCTION CONT'D. COUNTIES CD CC az Q az az o>- UJ o a: a: <3- UJ 7 in o cc az Q DC a: oo>- en UJ cc =3 ismn 5-19 OTHER ISCHEMIC HEART DISEASE During 1981, almost 97 percent of the 5,036 North Carolina deaths due to ischemic heart disease other than acute myocardial infarction involved chronic forms of ischemic heart disease. The overall death rate was 84.5 per 100,000 population, up 4.4 percent from the 1979 rate of 80.9. Caution must be exercised in discussing any pre-1979 rates for other ischemic heart disease because of changes in the ICD codes. As described in Section II, these changes made it necessary to correct the 1974-78 rates to make comparisons with 1979-81. A close examination of the 1979-81 age-adjusted rates and the corrected 1974-78 rates reveals a decline of 15 percent in the overall rate. Each of the four race-sex groups experienced a decline, the largest among nonwhite females (33%) and the smallest among white males (3.4%). The 1979-81 age-adjusted rates were as follows: 78.2 for white males, 33.8 for white females, 83.5 for nonwhite males, and 45.0 for nonwhite females. Along with the reduction in rates, the gaps in risk declined between nonwhite and white males (from a nonwhite/white ratio of 1.32 to 1.07) and between nonwhite and white females (from a ratio of 1.59 to 1.33). Geographic Patterns As exhibited in Figure 5. A, the 1979-81 rates appear to be somewhat higher in the northeast, but no strong patterns are evident. Wilkes, Polk, and Johnston counties had the highest unadjusted mortality rates for other ischemic heart disease in the 1979-81 period. Adjusting for age, race, and sex, Figure 5.B shows an apparent band of high-rate counties (Levels 4-6) in 5-21 the eastern portion of the state and comparatively low rates in the higher elevations of the west. The eastern cluster of high adjusted rates was found to be statistically significant based on procedures described in Section II. Among the 18 counties with the highest rates, the map below shows a significant geographic cluster of seven counties from Pitt to Cumberland. As other high-rate counties are included (up to the highest 35 counties) , most are consistently adjacent to this central cluster of seven counties in the east, making an even stronger cluster of eastern counties with high adjusted mortality rates from other ischemic heart disease. Only five of the 35 high-rate counties are in the west. OTHER ISCHEMIC HEART DISERSES AGE-RACE-SEX ADJUSTED MORTALITY RATES PER 100,000 POPULATION 103.1 - 186.8 (p=.0075) 3 9944..22 - 110011..99 <(cpc==..0022)) [7] 87.8 - 94.0 (p <.01) NORTH CAROLINA RESIDENT DATA 1979 - 1981 0.0 - 87. " 5-22 TABLE 5 MORTALITY STATISTICS FOR 1961 NORTH CAROLINA RESIDENTS OTHER FORMS OF ISCHEMIC HEART DISEASE GEOGRAPHICAL MORTALITY STATISTICS FOR 1981. NORTH CAROLINA RESIDENTS OTHER FORMS OF ISCHEMIC HEART DISEASE CONT'O. LU CO cn LU CO I— I Q cc CE CJ LU zn CD CO az LU en in LU SQD 5-25 LU CO cn LU CO cc cc LU CJ CJ CO cc LU o cn in CC ld cn oo oo EQD 5-27 HYPERTENSION Hypertension, or high blood pressure, is relatively common in the United States today. It was estimated in the 1971-74 period that nearly 1 out of 5 Americans ages 18-74 had elevated blood pressure (7). This estimate does not include persons who had their hypertension under control through the use of medication or diet, nor does it include persons with borderline hypertension or institutionalized persons with hypertension. In each of the years 1976 through 1979 it was estimated through the North Carolina Citizen Survey that close to 20 percent of North Carolina adults had been diagnosed by a doctor as having hypertension (8) . Hypertension is more prevalent among blacks and more frequently found among older people than young people. At the younger ages, the prevalence of hypertension is higher among men, whereas at older ages it is higher for women, with the crossover occurring at earlier ages for blacks (7). In 1970 the corrected (for reasons described in Section II) North Carolina death rate for hypertension as the underlying cause was 6.2 per 100,000 population, while in 1981 this rate was 4.0, indicating a substantial decrease over the decade. Part of this decrease could, however, reflect changes in death certificate coding practices. The following table compares the age-adjusted underlying cause hypertension death rate for four race-sex groups between the pariods 1974-78 and 1979-81. Tha earlier rate has been adjusted for both changes in the ICD and changes in population bases to correct for underestimates. These rates also show a decline over time, but what stands out are the differences among 5-29 1974-78 death certificate is unknown. Of these 4,310 deaths with mention of hypertension, 60.1 percent had heart disease as the underlying cause of death, 17.3 percent had cerebrovascular disease as the underlying cause, and 3.3 percent had diabetes. Around 15 percent of all deaths attributed to heart disease, cerebrovascular disease, and diabetes had a mention of hypertension. Nonwhites had roughly twice as many death certificate mentions of hypertension per 100,000 population as whites. Risk Factors People are often unaware that they have high blood pressure because there are no distinctive physical or psychological symptoms. The cause of the most common form of hypertension is basically unknown, though smoking, high sodium diets, family history, obesity, age, physical inactivity, and stress are known to be contributing factors. Blacks are more prone to hypertension than whites, but diet, stress, and other factors may underlie this racial association. It has been demonstrated that treatment and control of existing high blood pressure reduces the risk of subsequent stroke as well as heart and renal failure (1) . The risk of hypertension is also associated with certain characteristics of a modern society. "The average blood pressure trend by age in different societies is roughly proportional to their degree of modern social transformation, in particular to the elevation of disruptive migration, labor market competition/unemployment, and overwork characteristic of capitalist modernization. Members of untouched primitive societies or traditional hierarchical agricultural civilizations have blood pressures at low levels through the life span; those in developed societies have sharply rising average blood pressure trends by age which diverge from primitive levels 5-31 during adolescence or labor market entry ages" (9). Within the constraints of a modern society. North Carolinians must concentrate on lifestyle and medical strategies for reducing hypertension. Geographic Patterns No attempt is made here to assess county-by-county geographic variations in the underlying hypertension death rate because the number of such deaths in the 1979-81 period averages only 7.1 per county and at least 20 deaths are needed to produce a reasonably stable rate. Data from the section on "Multiple Conditions Present at Death" do suggest that the eastern region of the state has a substantially higher rate of hypertension mentions than other areas of the state. Since this region has a large nonwhite population, and the prevalence of hypertension is higher among nonwhites, this rate is expected to be somewhat higher. But even the race-specific rates in the eastern region are considerably higher than for North Carolina as a whole, and so the higher overall rates appear to be due also to a higher risk of hypertension in eastern North Carolina, though it is possible that death certificate recording practices contribute to this difference. In the section of this volume on "Multiple Conditions Present at Death," there are county maps showing 1979-81 hypertension mentions per 100,000 population, with an associated analysis. An average of 127 hypertension mentions per county in the 1979-81 period makes these rates much more stable than those for hypertension as the underlying cause, though differences in physician coding practices may complicate this county-by-county assessment. 5-32 TABLE 6 MORTALITY STATISTICS FOR 1981 NORTH CAROLINA RESIDENTS HYPERTENSION WITH OR WITHOUT RENAL DISEASE GEOGRAPHICAL MORTALITY STATISTICS FOR 1981. NORTH CAROLINA RESIDENTS HYPERTENSION WITH OR WITHOUT RENAL OISEASE CGNT'O. COUNTIES (CONT'D) 42 HALIFAX 43 HARNETT 44 HAYWOOD 45 HENDERSON 46 HERTFORD 47 HOKE 46 HYDE 49 IREDELL 50 JACKSON 51 JOHNSTON 52 JONES 53 LFE 54 LENOIR 55 LINCOLN 56 MCDOWELL 57 MACON 56 MADISON 59 MARTIN 60 MECKLENBURG 61 MITCHELL 62 MONTGOMERY 63 MOORE 64 NASH 65 NEW HANOVER 66 NORTHAMPTON 67 ONSLOW 66 ORANGE 69 PAMLICO 70 PASOUOTANK 71 PENDER 72 PERQUIMANS 73 PERSON 74 PITT 75 POLK 76 RANDOLPH 77 RICHMOND 76 ROBESON 79 ROCKINGHAM 80 ROWAN 61 RUTHERFORD 8? SAMPSON 83 SCOTLAND 64 STANLY 65 STOKES 66 SURRY 87 SWAIN 68 TRANSYLVANIA 89 TYRRELL 90 UNION 91 VANCE 92 WAKE 93 WARREN 94 WASHINGTON 95 WATAUGA 96 WAYNE 97 WILKES 96 WILSON 99 YADKIN 100 YANCEY NUMBER CEREBROVASCULAR DISEASE Cerebrovascular disease, or stroke, claimed the lives of 4,717 North Carolinians during 1981. Tt ranked as the thir^ leadinq cause of death in North Carolina with -in overall rate of 79.1 per 100,000 population. The North Carolina unadjusted rate was 10 percent higher thin the U.S. rate, but its age-adjusted rate was 27 percent higher which indicates that North Carolina would have a considerably higher stroke death rate if its ^ge structure were 1 ike that of the U.S. The state's 1981 cerebrovascular mortality rate was the lowest since 194°). Reductions in the rates have occurred for all four rac-^-sex groups. Nonwhite males and females, who had the highest rates during the 1979-31 period, experienced th° smallest, percent reductions in rates from the 1974-78 period. The 1979-H1 adjusted rates for the race-sex qroups were 50.1 for white males, 39.5 for white females, 98.2 for nonwhite males, and 66.3 for nonwhite females. Tn this period, nonwhite m^les had the highest risk of mortality from stokes for all ages under 85. For th 3 85-and-over aqo group, white females and white males had the highest rates. Risk Factors The risk factors associated with cerebrovascular disease are essentially the s~me as those for heart disease: high cholesterol, high blood pressure, atherosclerosis, heavy smoking, diabetes, lack of exercise, stress, and age (1,3, A, 6). Consistent with higher rates of hypertension and atherosclerosis mortality for nonwhites, nonwhites suffer a higher incidence of stroke mortality and at a mu^h earlier ag-^ (10). 5-35 Factors possibly associated with reduced cerebrovascular and other cardiovascular mortality are improved patient and physician education a.nd increased availability of medical services including rescue squads, coronary car-"1 units, and physician supply (4). Geographic Patterns Figure 7. A shows a scattering of counties with relatively high unadjusted rates (Leve's 4-6) and several pockets of high-rate counties, primarily in the east. After adjusting for age, race, and sex (Figure 7.B) , even more counties appear in the high-rate group. Further, these high-rate counties are concentrated in both the central and eastern portions of the state, although th^re is an apparent band of inordinately high rates (Levels 5-6) extending from Halifax down to New Hanover County and across to Richmond. Based on procedures described in Section II, the eastern pockets of high unadjusted county rates were found to cluster geographically (see unadjusted map on next page). Spatial clustering continues to prevail in the east after adjusting for age, race, and sex (see adjusted map on next page). Thus, it is :1< ar that some eastern North Carolina counties are experiencing inordinately high cerebrovascular mortality that cannot be explained by age, race, and sex factors. 5-36 CERbBRUVrr CULAR Dl! EASE MURrnu ry r.rtes PER 100.000 PuPULflTluN 116.2 - 176.4 (p=.003) !S 107.2 - 115.3 (p=.007) fj 0.0 - 107.1 NORTH CAROLINA RESIDENT DATA 1979 - 1981 CEREBROVASCULAR DISEASE AGE-RACE-SEX ADJOSTED MORTALITY RATES PER 100.000 POPULATION 110.2 - 132.9 (p=.033) gj 100.5 - 106.5 (p=.0025) 91.5 - 100.0 (p=.001) fj 0.0 - 91.4 NORTH CAROLINA RESIDENT DATA 1979 - 1981 5-37 GEOGRAPHICAL AREA T A B L t 7 MORTALITY STATISTICS FOR 19ei NORTH CAROLINA RESIOENTS CEREBROVASCULAR DISEASE NUMBER DEATH OF DEATHS RATE* 1979-81 1979-61 NUMBER MORTALITY STATISTICS FOR 1981, NORTH CAROLINA RESIDENTS CEREBROVASCULAR DISEASE CONT'D, COUNTIES ICONT'D) 42 HALIFAX 43 HARNETT 44 HAYWOOD 4b HENDERSON 46 HERTFORD 47 HOKE 46 HYDE 49 IREDELL 50 JACKSON 51 JOHNSTON 52 JONES 53 LEE 54 LENOIR 55 LINCOLN 56 MCDOWELL 57 MACON 58 MADISON 59 MARTIN 60 MECKLENBURG 61 MITCHELL 62 MONTGOMERY 63 MOORE 64 NASH 65 NEW HANOVER 66 NORTHAMPTON 67 ONSLOW 68 ORANGE 69 PAMLICO 70 PASQUOTANK 71 PENDER 72 PEROUIMANS 73 PERSON 74 PITT 75 POLK 76 RANDOLPH 77 RICHMOND 78 ROBESON 79 ROCKINGHAM 80 ROWAN 81 RUTHERFORD 82 SAMPSON 83 SCOTLAND 84 STANLY 8b STOKES 86 SURRY 87 SWAIN 88 TRANSYLVANIA 89 TYRRELL 90 UNION 91 VANCE 92 WAKE 93 WARREN 94 WASHINGTON 95 WATAUGA 96 WAYNE 97 WILKES 98 WILSON 99 YADKIN 100 YANCEY NUMBER CO CE UJ CO I— I Q CC en CJ CO CE >o cc CD UJ CC UJ CJ cr CD EED 5-41 UJ CO ac LU CO i— i Q CC cc CJ> CO cr >o CC CO LU CC LU CJ CD O LxJ CC ZD CD J 00 ATHEROSCLEROSIS Atherosclerosis (called arteriosclerosis in this publication before 1979) is a general term covering a number of diseases of the blood vessels and is often called "hardening of the arteries." Like hypertension, atherosclerosis is listed as a contributing cause on the death certificate far more often than it is assigned as the underlying cause of death. In particular, atherosclerosis contributes to deaths from heart disease, stroke, and diabetes. It was estimated that in 1970, 87 percent of the more than 1 million deaths in the United States due to heart and blood vessel diseases were attributable to atherosclerosis and its sequelae (1). In 1970 the North Carolina death rate for atherosclerosis as the underlying cause was 12.7 per 100,000 population, while in 1981 this rate was 9.7, indicating a 24 percent decline over the decade. Part of this change, however, could be due to changes in death certificate coding practices. Also, the implementation of a computerized system for assigning underlying cause in 1975 resulted in some deaths being assigned to ischemic heart disease that would have formerly been assigned to atherosclerosis (11). Comparisons of the age-adjusted atherosclerosis death rates for the four race-sex groups between the periods 1974-78 and 1979-81 (the 1974-78 rates were corrected for changes in the ICD and in population bases) shows a decline over time for each group. White males had the largest percent decline (30.4%), followed by white females (22.7%), nonwhite females (16.4%), and nonwhite males (9.4%). Noteworthy are the sex and race differentials. The white male rate (5.5) was 25 percent higher than the white female rate (4.4) 5-45 in 1979-81 and the nonwhite male rate (8.4) was 38 percent higher than the nonwhite female rate (6.1). Nonwhites had higher atherosclerosis (underlying cause) death rates than whites, 53 percent higher for males and 39 percent higher for females. "The (underlying cause) death rate for atherosclerosis in the 1979-81 period showed a sharp increase with age for all four race-sex groups to a high in the 85-and-over age group of 555 for white males, 547 for white females, 341 for nonwhite males, and 362 for nonwhite females. The higher overall rate for males is due particularly to higher rates in the 35-74 age groups. The higher overall rate for nonwhites is due to higher rates in the under-85 age groups. In 1981 there were 580 deaths with atherosclerosis as the underlying cause, but over 14,700 death certificates had a mention of atherosclerosis. This suggests that 30 percent of all North Carolina deaths in 1981 involved atherosclerosis, though it is not known just how completely this condition is recorded on the death certificate. Of these 14,723 deaths with mention of atherosclerosis, 65 percent had heart disease as the underlying cause of death and 14 percent had cerebrovascular disease listed as the underlying cause. Around 50 percent of the deaths with heart disease or cerebrovascular disease as the underlying cause had a mention of atherosclerosis. In 1978, white males had the highest rate of mentions of atherosclerosis per 100,000 population (366) , with white females and nonwhite males close together at a lower level (about 300), and nonwhite females much lower still (257). The reasons for the difference between this race-sex pattern and that based on underlying cause are not clear, though the rates for mentions of atherosclerosis are based on about 25 times as many deaths as the rates using underlying cause. 5-46 Risk Factors Three major risk-treatable factors contributing to atherosclerosis have been identified: elevated blood cholesterol levels, high blood pressure, and cigarette smoking. A number of additional factors are also recognized, such as diabetes, physical inactivity, obesity, age, male sex, and certain personality types, that is, "type A" or coronary-prone behavior (1). While older males generally have the highest atherosclerosis death rates, women and young people are also at risk of this disease. The theory that atherosclerosis begins during childhood and continues to develop through adulthood has begun to receive considerable attention (2). Increasing epidemiological evidence supports the hypothesis that higher concentrations of high-density lipoproteins (HDL's) may be a protective factor in the development of atherosclerosis. "Levels of HDL have been correlated positively with exercise and moderate ingestion of alcohol and inversely related to obesity, smoking, poor control of diabetes, and the use of progest in-containing contraceptives" (1). The cause and effect of the inverse relationship between HDL and atherosclerosis, however, remain unclear. Geographic Patterns Upon examining geographic variation in the atherosclerosis (underlying cause) death rate using the clustering technique described in Section II, a significant cluster of counties with high adjusted rates in southcentral North Carolina was revealed. Richmond, Moore, Scotland, Hoke, Robeson, and Cumberland counties, all contiguous, had some of the highest 1979-81 age- race-sex- adjusted rates in the state. Nearby counties that also had high adjusted rates are Rowan, Union, and Brunswick. This apparent pattern should be considered very cautiously since the numerators of some of these rates are 5-47 very small. Consequently, it was decided to show the two major maps on atherosclerosis using mentioned conditions rather than underlying cause data. These maps, along with an associated analysis, are presented in the Multiple Conditions Section (Section X) and show 1979-81 atherosclerosis mentions per 100,000 population. ATHEROSCLEROSIS AGE-RACE-SEX ADJUSTED MORTALITY RATES PER 100,000 POPULATION NORTH CAROLINA RESIDENT DATA 1979 - 1981 B| 15.6 - 33.8 (p=.007) 0.0 - 15.5 5-48 TABLE 8 MORTALITY STATISTICS FOR 1981 NORTH CAROLINA RESIDENTS ATHEROSCLEROSIS GEOGRAPHICAL AREA NORTH CAROLINA REGIONS NUMBER MORTALITY STATISTICS FOR 1981, NORTH CAROLINA RESIDENTS ATHEROSCLEROSIS CONT'D. COUNTIES (CONT'D) 42 HALIFAX 43 HARNETT 44 HAYWOOD 45 HENDERSON 46 HERTFORD 47 HOKE 48 HYDE 49 IREDELL 50 JACKSON 51 JOHNSTON 52 JONES 53 LEE 54 LENOIR 55 LINCOLN 56 MCDOWELL 57 MACON 56 MADISON 59 MARTIN 60 MECKLENBURG 61 MITCHELL 62 MONTGOMERY 63 MOORE 64 NASH 65 NEW HANOVER 66 NORTHAMPTON 67 ONSLOW 68 ORANGE 69 PAMLICO 70 PASQUOTANK 71 PENOER 72 PER8UIMANS 73 PERSON 74 PITT 75 POLK 76 RANDOLPH 77 RICHMOND 76 ROBESON 79 ROCKINGHAM 60 ROWAN 81 RUTHERFORD 82 SAMPSON 83 SCOTLAND 84 STANLY 85 STOKES 86 SURRY 87 SWAIN 88 TRANSYLVANIA 89 TYRRELL 90 UNION 91 VANCE 92 WAKE 93 WARREN 94 WASHINGTON 95 WATAUGA 96 WAYNE 97 WILKES 96 WILSON 99 YADKIN 100 YANCEY NUMBER REFERENCES FOR SECTION V 1. Levy, R.I.; Moskowitz, J. "Cardiovascular Research: Decades of Progress, A Decade of Promise," Science . Volume 217, July 9, 1982, pp. 121-129. 2. United States Department of Health and Human Services, Public Health Service, National Center for Health Statistics. "Annual Summary of Births, Deaths, Marriages, and Divorces: United States 1981," Monthly Vital Statistics Report . (PHS) 83-1120, Volume 30, Number 13, Hyattsville, Maryland, December 20, 1982. 3. United States Department of Health and Human Services, Public Health Service, National Center for Health Statistics. "Dietary Intake and Cardiovascular Risk Factors, Part I - Blood Pressure Correlates: United States 1971-75," Vital and Health Statistics . Series 11, Number 226, DHHS Pub. No. (PHS) 83-1676, U.S. Government Printing Office, Washington, D.C., February 1983. 4. Tyroler, H.A.; Haynes, S. "Community Cardiovascular Surveillance Program: Phase II - Protocol ," Unpublished Paper, Department of Epidemiology, School of Public Health, UNC-Chapel Hill, N.C., April 1982. 5. Paffenbarger, R.S.; Brand, R.J.; Sholtz, R.I.; Jung, D.L. "Energy Expenditure, Cigarette Smoking, and Blood Pressure Level As Related to Death from Specific Diseases," American Journal of Epidemiology . Volume 108, Number 1, 1978, pp. 12-18. 6. Laporte, R.E. ; Cresanta, J.L. ; Kuller, L. H. "The Relation of Alcohol to Coronary Heart Disease and Mortality: Implications for Public Policy," Journal of Public Health Policy . September 1980, pp. 198-223. 7. Fingerhut, L.A.; Wilson, R.W. ; Feldman, J.J. "Health and Disease in the United States," Annual Review of Public Health 1980 . Number 1, pp. 1-36. 8. North Carolina Department of Health and Human Resources, Division of Health Services, State Center for Health Statistics. "Update on Health Characteristics of Adult Residents of North Carolina's Health Service Areas," SCHS Studies . Number 19, November, 1980. 9. Eyer, J. "A Diet/Stress Interaction Hypothesis of Coronary Heart Disease Epidemiology," International Journal of Health Services . Volume 9, Number 1, 1979, pp. 161-168. 10. North Carolina Department of Human Resources, Division of Health Services, State Center for Health Statistics. "Wide Gaps in Mortality Risk: Comparisons Among Race-Sex Groups Across Time and Space Dimensions," SCHS Studies. Number 18, Raleigh, August, 1980. 5-51 11. U.S. Department of Health and Human Services, Public Health Service, Office of Health Research, Statistics, and Technology, National Center for Health Statistics. Vital Statistics: Instructions for Classifying Multiple Causes of Death, 1981 , Part 2b' Hyattsville, Maryland, November 1980. 5-52 VI. Cancer Mortality CANCER Cancer is the secord most frequent cause of death in the united States, and unlike mortality from other major diseases, cancer mortality continues to increase. As a result, beginning in 1977, North Carolina's cancer death toll has exceeded the toll from heart attack and in 1981 was 24 percent higher. But despite appearances to the contrary, cancer is not entirely a product of modern times. It has been reported that, even by the 7th century, the origin of its name—"cancer," the crab—had al ready been lost in antiquity. In fact, based on findings of large tumorous messes extruding from the petrified bones of unearthed dinosaur remains, cancer seems to have predated man himsel f . (1) Still, there continues to accumulate an overwhelming body of statistical evidence that modern-day 1 ifestyl es and technologies are exacerbating the cancer problem. While the exact patho-physiological mechanisms of the disease remain largely unknown, a number of external chemical and physical agents known as carcinogens have been implicated. In the meantime, North Carolina's health community is treating cancer as a major public health issue as evidenced by not only advanced research and treatment in our medical institutions but also the Division of Health Services' involvement in a variety of prevention, diagrosis/treatment , and epidemiologic research efforts: • Available in most local health departments and in 25 comprehensive screening centers across the state, cancer screening services consist of Pap smears, blood tests, urinalysis, X-ray, and patient histories. Educational information, e.g., how to conduct breast self-examination, is also provided. 6-3 • Ihe Mult Health Section administers a financial aid program for cancer diagnosis and treatment of lower-income patients not receiving financial aid from any other source. • To aid in evaluating treatment practices, the Adult Health Section maintains the North Carolina Cancer Registry which collects diagnosis, treatment, and follow-up information on cancer patients treated in participating hospitals. Unfortunately, hospital participation is or, a voluntary basis. • The Epidemiology Section is developing an environmental epidemiology program that conducts investigations of possible carcinogens in high-risk areas of the state. e The State Center for Health Statistics reports county, regional, state, and nationwide statistical information gleaned from death certificates, hospital discharge records, household surveys, and epidemiologic investigations. Clinical arid Epidemiologic Research Recent discoveries have spurred hope that cancer researchers may soon find ways to prevent or effectively treat the dread disease. Cne discovery is that normal human cells contain genes that have potential oncogenic activity. The hope is that, by learning what makes such genes trigger cancer, researchers can find ways to prevent it or at least to identify and stop the process once it's begun. Cooper (2) suggests, however, that, ". . . it is likely that activation of these genes is only one of several events involved in carcinogenesis." Further, Rubin (3) warns that explanations for the origin of cancer have been varied and plentiful in this century and the rush to accept the "oncogene" explanation is "at best premature." A discovery about 10 years ago also provides impetus for current cancer research—that of natural killer (NK) cells that have the spontaneous ability to destroy tumor cells as well as cells infected with viruses. Since reactivity of those cells can be rapidly augmented by interferon, it is conceivable that through immunoprevent ion or immunotherapy, NK cells might 6-4 eventually be harnessed as a viable cancer fighter. Herberman notes, however, that there remain several practical problems in conducting experiments to substantiate a major role for NK cells in resistance against tumor growth. (4) Those problems notwithstanding, several sponsors including the American Cancer Society (ACS) continue to support interferon research in this country. In addition to those particular studies, the ACS funds research in the broad areas of genetic engineering, man-made antibodies, the mechanisms of carcinogensis, and chemopr event ion, among others. As a result, $62.7 million or 31 percent of the ACS's 1981/82 budget was expended for research. (5) Concurrently, it has been estimated that 70-90 percent of human cancers are likely spawned by environmental factors (6), and both human and animal studies continue to contribute evidence involving the following categories of agents (7): - Consumables: tobacco, alcohol, food including coffee, saccharin, and other nor.nutr ients, drugs such as antineoplastic agents and the estrogens, and cosmetics including hair dye, alcoholic mouthwash, and tal cum powder ; - Contaminants: asbestos, compounds of certain metals, various organic chemicals, various radionuclides, wood dusts, air, water, man-made food additives, biologic agents, and physical agents including ultraviolet and ionizing radiation. Numerous epidemiologic studies have ascribed carcinogenic qualities to the above agents while producing equivocal results regarding some of those as well as other agents in the environment. In order to come to grips with the resulting confusion and conflicting information, the American Cancer Society is undertaking a six-year comprehensive survey of more than 1 million Americans who will be studied for factors related to personal habits, lifestyle, and environmental conditions. The society will correlate these factors with disease incidence and report findings late in the decade. (8) 6-5 In the meantime, the work of epidemiologists has been graphically described by Shod el 1 (1): "Epidemiologists are like bookies of disease, stalking the globe to determine point-spreads on which groups of people are most likely to get which disease." As a result of this work, a world cancer map is emerging. The patterns reveal that all peoples are susceptible to cancer but with widely varying propensities for specific types. In the U
Object Description
Description
Title | North Carolina vital statistics, vol 2 |
Other Title | Leading causes of mortality |
Contributor | North Carolina. |
Date | 1981 |
Subjects |
Mortality--North Carolina Vital Statistics--North Carolina North Carolina--Statistics, Vital--Periodicals North Carolina--Statistics Public health--North Carolina Women Education |
Place |
Raleigh, Wake County, North Carolina, United States North Carolina, United States |
Time Period |
(1945-1989) Post War/Cold War period |
Description | Vols. for <1971>- issued in 2 vols.: vol. 1: Population, births, deaths, marriages, divorces (changed to: Births, deaths, population, marriages, divorces, 1974- ); vol. 2: Leading causes of mortality (changed to: Leading causes of death, 1994- ).; Vol. for 1972 issued by the N.C. Dept. of Human Resources, Public Health Statistics Services; 1973-1978 by the N.C. Dept. of Human Resources, Public Health Statistics Branch; 1979-1987 by the State Center for Health Statistics; 1988-1989 by the Center for Health and Environmental Statistics; 1990-1994 by the State Center for Health and Environmental Statistics; 1995- by the State Center for Health Statistics. |
Publisher | Raleigh, N.C. :State Board of Health, Public Health Statistics Section,1965- |
Agency-Current | North Carolina Department of Health and Human Services |
Rights | State Document see http://digital.ncdcr.gov/u?/p249901coll22,63754 |
Physical Characteristics | v. ;28 cm. |
Collection | Health Sciences Library. University of North Carolina at Chapel Hill |
Type | text |
Language |
English |
Format |
Annual reports Statistics Periodicals |
Digital Characteristics-A | 13786 KB; 408 p. |
Digital Collection |
Ensuring Democracy through Digital Access, a North Carolina LSTA-funded grant project North Carolina Digital State Documents Collection |
Digital Format | application/pdf |
Related Items | Vol. for 1972 issued by the N.C. Dept. of Human Resources, Public Health Statistics Services; 1973-1978 by the N.C. Dept. of Human Resources, Public Health Statistics Branch; 1979-1987 by the State Center for Health Statistics; 1988-1989 by the Center for Health and Environmental Statistics; 1990-1994 by the State Center for Health and Environmental Statistics; 1995- by the State Center for Health Statistics. |
Title Replaces | North Carolina. Public Health Statistics Section..Annual report of Public Health Statistics Section |
Audience | All |
Pres File Name-M | pubs_edp_ncvitalstatistics1981v2.pdf |
Pres Local File Path-M | \Preservation_content\StatePubs\pubs_edp\images_master\ |
Full Text |
THE LIBRARY OF THE
UNIVERSITY OF
NORTH CAROLINA
AT CHAPEL HILL
THE COLLECTION OF
NORTH CAROLINIANA
C614.1
N8?v5
1979/31
_
UNIVERSITY OF N.C AT CHAPEL HILL
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00034018704
FOR USE ONLY IN
NORTH CAROLINA COLLECTION
I
Digitized by the Internet Archive
in 2009 with funding from
Ensuring Democracy through Digital Access (NC-LSTA)
http://www.archive.org/details/northcarolinavit197902nort
LEADING CAUSES
OF MORTALITY
North Carolina
Vital Statistics
1981—Volume 2
LEADING CAUSES
OF MORTALITY
North Carolina
Vital Statistics
1981—Volume 2
A A
State Center For Health Statistics
EC. Department of Human Resources
DiTiason of Health Semes
STATE OF NORTH CAROLINA
James B. Hunt, Jr., Governor
DEPARTMENT OF HUMAN RESOURCES
Sarah T. Morrow, M.D., M.P.H., Secretary
DIVISION OF HEALTH SERVICES
Ronald H. Levine, M.D., M.P.H.
State Health Director
Margaret Woodcock, M.A., M.P.A.
Asst. Director for Management Services
STATE CENTER FOR HEALTH STATISTICS
Charles J. Rothwell, M.B.A., M.S., Director
September 1983
TABLE OF CONTENTS
PREFACE
I. INTRODUCTION
A. Purpose and Organization
B. Overview of Mortality in North Carolina
II. TECHNICAL NOTES
A. Changes in the Cause-of-Death Classification System . .
B. Changes in Population Bases Due to the 1980 Census . .
C. Mortality Rates
Computation of Mortality Rates
Interpretation of Mortality Rates
Flagging Biased Rates
D. Procedure for Geographic Clustering of Counties ....
III. NORTH CAROLINA'S POPULATION AND HEALTH CARE RESOURCES ... 3-
IV. GENERAL MORTALITY IN NORTH CAROLINA 4-
V. MAJOR CARDIOVASCULAR DISEASE MORTALITY 5-
A. Heart Disease
Acute Myocardial Infarction
Other Ischemic Heart Disease
B. Hypertension With or Without Renal Disease
C. Cerebrovascular Disease
D. Atherosclerosis
VI. CANCER MORTALITY 6-1
A. Total Cancer 6-3
B. Cancer of the Stomach 6-23
C. Cancer of the Colon, Rectum, and Anus 6-31
D. Cancer of the Pancreas 6-41
E. Cancer of the Trachea, Bronchus, and Lung 6-49
F. Cancer of the Female Breast 6-59
G. Cancer of the Cervix Uteri 6-67
H. Cancer of the Ovary and Other Uterine Adnexa 6-75
I. Cancer of the Prostate 6-83
J. Leukemia 6-91
TABLE OF CONTENTS (CONTINUED)
Page
VII. OTHER SELECTED CAUSES OF MORTALITY 7-1
A. Diabetes Mellitus 7-3
B. Influenza and Pneumonia 7-9
C. Chronic Obstructive Pulmonary Disease 7-19
D. Chronic Liver Disease and Cirrhosis 7-29
E. Nephritis, Nephrotic Syndrome, and Nephrosis 7-37
VIII. MAJOR EXTERNAL CAUSES OF MORTALITY 8-1
A. Accidents 8-3
Motor Vehicle Accidents 8-5
Accidents Excluding Motor Vehicles 8-15
B. Suicide 8-25
C. Homicide 8-35
IX. INFANT MORTALITY 9-1
X. MULTIPLE CONDITIONS PRESENT AT DEATH 10-1
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PREFACE
The State Center for Health Statistics has produced triennially a major
publication describing North Carolina's mortality experience for a five-year
period. Such a publication was due for 1975-79 data, but the change in 1979
from the Eighth to the Ninth Revision of the International Classification of
Diseases (ICD) made it undesirable to combine pre-1979 cause-of-death data
with data for 1979 and later years. Changes in the cause-of-death
classification were described in detail in the abbreviated 1979 edition
Leading Causes of Mortality . The standard format is resumed in this 1981
_
edition, with three-year rates (1979-81) replacing five-year rates. The delay
in publishing this volume has been largely due to a delay in obtaining the
1981 population projections based on the 1980 census, which are used in the
denominators of the death rates.
This edition of Leading Causes of Mortality is the third major
publication of its type on North Carolina's mortality experience. This volume
includes statistical tables, maps, and graphs, as well as cause-specific
discussions of trends, geographic patterns, risk factors, and recent research.
An overview of the mortality experience in North Carolina is also presented.
The tables in this report provide selected 1981 mortality statistics for
counties, Department of Human Resources regions. Health Service Areas, and the
state (see maps on preceding pages). More than a dozen of North Carolina's
leading causes of mortality are depicted in these tables; in addition, various
cancer sites and total infant mortality are included.
Similar to the last major publication, multiple conditions present at
death are included in this volume. This section highlights the 1982
publication Multiple Conditions Present At Death: A Special Study and presents
the data for 1981 deaths.
A separate technical notes section has been included in this publication.
This section is necessary not only to discuss appropriate interpretation (s) of
mortality rates and changes in both the ICD codes and population bases, but
also to introduce two new statistical procedures used in this volume—Flagging
Biased Rates and Geographic Clustering of Counties. Both procedures are
discussed in detail in Section II and where relevant in the other sections.
Special thanks go to Mr. Shannon Hallman of the Health Services Research
Center, University of North Carolina at Chapel Hill for preparing Section
III—North Carolina's Population and Health Care Resources. For the first
time data have been included on nurse practitioners and physician assistants
and on skilled nursing and intermediate care beds.
If there are any questions concerning this publication, please contact:
Delton Atkinson
State Center for Health Statistics
Division of Health Services
P. 0. Box 2091
Raleigh, North Carolina 27602
(919) 733-4728
I. Introduction
PURPOSE AND ORGANIZATION
Although North Carolina has traditionally experienced low death rates,
our status among states has worsened. In 1960, only seven of the 50 states
had death rates lower than North Carolina, and this increased to 14 in 1970
(1). In 1981, 20 states had lower rates and three had the same rate (2).
Furthermore, while many of the state's cause-specific rates are still below
United States levels, North Carolina's age-adjusted rates are usually higher.
For example, cerebrovascular disease, motor vehicle accidents, all other
accidents and adverse effects, pneumonia and influenza, and nephritis,
nephrotic syndrome, and nephrosis are causes for which North Carolina's 1981
adjusted rates were at least 10 percent above the corresponding United States
rates.
These facts represent a serious challenge to health officials throughout
the state to (i) identify high-risk areas in order to strategically apply
medical and other health services, and (ii) isolate those determinants of
mortality that permit intervention. The data in this volume are intended to
aid in these areas of investigation by providing information against which
North Carolina's county and regional mortality may be assessed in the present
and evaluated in the future.
Ten sections comprise this edition of Leading Causes of Mortality . This
section presents an overview of mortality experience in North Carolina as well
as the purpose and organization of the document. Section II provides
information concerning the calculation, interpretation, and appropriate use of
adjusted and unadjusted rates. In past editions of this volume, readers were
1-3
cautioned about using adjusted rates with a small number of deaths in the
numerator. For this and subsequent editions, problem rates have been
"flagged" in the tables with an asterisk. The procedures used to determine
which rates to flag are described in detail in Section II. Also, a new
procedure used to depict geographic clustering of counties is discussed here.
In Sections III-X, maps and tabular data describe North Carolina's recent
experience with respect to population and selected health care resources,
general mortality, cause-specific mortality (underlying causes), infant
mortality, and multiple conditions present at death. Although the 1976
edition of this volume reported that some 3-year rates may have substantial
random fluctuations, changes in coding of death certificates in 1979
necessitate the use of these rather than 5-year rates. The 1982 edition of
Leading Causes of Mortality will show 4-year rates, and the 1983 and
subsequent editions will again show 5-year rates.
Table 1 on page 1-8 describes the selected cause-of-death categories in
terms of codes from the ninth revision of the International
Classification of Diseases (3). Altogether, the causes selected for
examination in this report accounted for 87 percent of all North Carolina
deaths during 1981.
Description Of Maps
This volume contains 81 computer-produced maps which depict data for the
state's 100 counties. The maps on pages v and vi identify the four regions of
the Department of Human Resources (DHR) and the state's six Health Service
Areas (HSA's)
.
In Section III, five maps portray each county's relative status among the
100 counties with respect to population per primary care physician; population
1-4
per primary care physician, physician assistant, and nurse practitioner;
population per registered nurse; population per short-term general hospital
bed; and population 75+ per skilled nursing and intermediate care beds. These
data together with information concerning county populations and county
mortality levels should aid in the determination of areas most in need of
increased health resources.
In Sections IV-X, the mgps depicting geographical patterns in mortality
should aid in the resolution of specific types of health promotion and health
care needs. Two to four maps are generally shown for each cause-of-death
category. Two maps depict the 1979-81 unadjusted death rate and the 1979-81
age-race-sex-adjusted death rate for each of the 100 counties. These two maps
show six levels of death rates, where level one is the lowest rate interval
and level six the highest . These maps should be viewed with extreme caution
for causes where the number of deaths per county is small, since in these
cases the rates may be very unstable. Users of the maps should note that the
interval values indicated by the map legends are not necessarily continuous
but reflect the actual range of values for each interval.
A clustering routine from the Statistical Analysis System (SAS) was used
to group counties that are "most like each other" with respect to their
unadjusted rate and then their adjusted rate (4). This procedure may result
in very large or very small groups depending upon how counties differ from one
another. The other two maps for a particular cause may depict "spatial"
clustering of two or more adjacent counties with high unadjusted and/or
adjusted rates using a new procedure described in Section II. These maps are
presented for a given cause only when a statistically significant spatial
cluster is found to exist. Unlike the two full-page maps, these maps are
presented in reduced form as part of the narrative and show one to three
1-5
interval levels of death rates, depending on the number of significant spatial
clusters found, along with the significance level (i.e., p-value)
.
Description Of Tables
Sections IV-X contain tables that summarize the recent mortality
experience of counties, six Health Service Areas, four Department of Human
Resources regions, and the state. Except in the case of infant deaths
(Section IX) , a table corresponding to each cause-of-death category includes
the following items of information:
(1) the number of resident deaths occurring during 1981;
(2) the 1981 death rate;
(3) the number of resident deaths occurring during 1979-81;
(4) the 1979-81 average annual death rate;
(5) the 1979-81 average annual age-race-sex-adjusted death rate computed
by the direct method (5).
The formulas for calculating single- and multi-year rates are found in
Section II. In this report, general mortality rates (all causes combined) are
expressed as deaths per 1,000 population while cause-specific rates are
expressed as deaths per 100,000 population. The infant death rates of Table
28, Section IX, are computed as the number of infant deaths per 1,000 live
births.
Multiple Conditions Present At Death
Since 1975, multiple conditions present at death have been coded such
that statistics are available for all conditions present at death as reported
by the certifier. Three diseases in particular—hypertension,
atherosclerosis, and diabetes—are considered associated conditions far more
often than they are considered an underlying cause; hence, no maps are
1-6
displayed in Sections V and VII showing these deaths as an underlying cause.
For the geographic clustering routine maps, only the 1979-81 age-race-sex-adjusted
county rates for these conditions are displayed in Section X. Two of
the three clustering maps displaying unadjusted rates showed patterns similar
to those for adjusted rates, and thus are not presented, while the third
(atherosclerosis) was not statistically significant.
Tables in Section X show deaths crosstabulated by underlying cause and
associated mentioned conditions, death frequencies for selected pairs of
mentioned conditions, and death rates based on mentioned conditions rather
than underlying cause. Rates are deaths with the condition mentioned per
100,000 population.
1-7
OVERVIEW OF MORTALITY IN NORTH CAROLINA
Mortality in North Carolina has exhibited a general downward trend in
this century. Numerous factors have contributed to this decline including
changes in lifestyles, environment, age-race-sex distribution, risk factors,
and the medical care system. In Sections IV through X of this report, these
factors and others are considered in discussing each cause of death. This
overview examines four general determinants of mortality, highlights some of
the major mortality findings, and describes some of the risk factors which
impact on a number of different causes. Further, this section looks at
premature mortality in North Carolina using a concept called "years of life
lost" which emphasizes mortality in the younger age groups (6).
Determinants of Mortality
A broad view of mortality determinants recognizes that medical care is
only one aspect of health maintenance and that many health problems "arise
from causes embedded in the social fabric of the nation as a whole" (7)
.
Accordingly, environment, lifestyle, biology, and medical care must all be
considered as determinants of health.
The natural and manmade physical environments are commonly recognized as
having an important impact on health. For example, water mineral content and
elevation have been cited as influencing the incidence of cardiovascular
disease (8) . Of particular concern recently have been the health consequences
of manmade environmental pollution. The proliferation of various chemical
compounds is a central element of a high-technology, growth-oriented society.
Ill health due to environmental pollution therefore can result from the
1-9
economic environment. Stricter governmental controls may be required in this
area for those businesses that will not voluntarily weigh social costs into
their economic calculations.
Yet economic growth bears on health in ways other than the negative
externalities of environmental pollution. Economic growth means jobs and
income, both of which are central to individual and family well-being.
Unemployment, economic poverty, and their social concomitants are inimical to
mental and physical health. The poor, controlling a lesser share of economic
and social resources, are subject to greater physical vulnerability to
infectious agents, more economic uncertainty and associated stress, and more
hazardous environments in homes and workplaces. They have fewer cushioning
devices such as vacation or travel (9) . Thus controlled growth can have
substantial health benefits if it is broadly based and environmentally sound.
Lifestyle refers to those decisions by individuals that affect their
health and over which they have some control. The degree of individual
control over one's own decisions is a key question to answer in an evaluation
of changing lifestyles as a health improvement strategy. Individuals'
decisions are conditioned to a large extent by their position in the economic
and social hierarchy. Self-destructive and violent behavior, for example, may
reflect alienation due to a marginal position in the society. But policies to
educate individuals about their health are much less complex and easier to
sell politically than those aimed at modifying basic social and economic
determinants of lifestyle and health. "Blaming the victim" by keeping the
problem at the individual level may obscure the origins of disease in the
socioeconomic environment.
This is not meant to suggest that health education does not have its
place. Certain population groups are more likely to engage in lifestyles that
1-10
increase mortality, and education programs that target these groups are an
essential, though short-run, complement to policies oriented toward the
environmental factors that condition lifestyle. Education about nutrition is
likely to have a high health payoff among the poor and less educated, but only
if they have enough money to buy proper food and the facilities to properly
prepare it.
A 1977 Rhode Island telephone survey indicated that the 30-39 year age
group could be targeted as high-risk, based on health perception, weight,
smoking, drinking, sleep habits, and stress. Education efforts aimed at
relieving stress, which is much less publicized than other lifestyle factors
and may affect smoking, drinking, and other behaviors, may be more productive.
As shown in a recent North Carolina study (10) , income, education, and urban
or rural residence may be important indicators and determinants of lifestyle,
and successful education programs must consider variation along such
dimensions. Targeting specific groups is likely to be more successful than
generalized education or media campaigns.
Biological factors are very pervasive determinants of mortality. The
age, race, and sex of an individual are biologically determined and mortality
rates vary consistently along these dimensions. Health is strongly tied to
aging and the life cycle, some diseases that vary by race are thought to be
genetically linked, and biological factors account in part for males and
females having a different incidence of many diseases, with females living
longer on the average. Some health consequences of age, race, and sex are,
however, not biological in origin. Social stratification is in large part
based on age, race, and sex differences, with the old, the nonwhite, and the
female generally being lower on the social and economic hierarchy. Male
mortality is higher partially as a result of aggressive, achievement-oriented
1-11
behavior that accompanies higher status positions (11), while higher nonwhite
mortality is due in part to a lower position in the economic hierarchy (12).
Many causes of disease are biological in origin. In North Carolina an
estimated 150,000 persons are suffering from serious genetic disorders as
evidenced by physical defects, mental retardation, and other health problems
(13) . Forty percent of all children admitted to inpatient pediatric care are
there because of genetic disorders (13). About one-half of all visual
impairment difficulties are caused by genetic factors. Birth defects, of
which about 80 percent are thought to be genetic in origin, are a leading
cause of infant mortality. Some persons have a greater biological
susceptibility to disease. Cancer, for example, may result from problems of
the immunological system, in combination with the presence of external agents.
Many parts of the medical care system function by reacting to health
problems caused elsewhere, though in attempting to restore individuals to a
full and productive life, this system becomes an important determinant of
mortality levels. Disease prevention is also within the purview of the
medical care system, as through innoculation against infectious diseases or
patient education concerning the negative health consequences of certain
lifestyles. Medical care personnel may also be involved in attacking certain
environmental and biological causes of disease, though this type of activity
has traditionally been carried out in the government or public sector.
McKeown and Brown (14) present evidence suggesting that medical practice
in the first half of the 19th century had very little to do with the large
decline in mortality that took place in Western societies, but rather that
transportation improvements, changes in the economic system that assured a
more continuous and nutritious food supply, and improved sanitation practices
urged on by reformers in the cities were responsible. After the practice of
1-12
antisepsis became widespread late in the 19th century, medical care became a
much more positive factor in reducing mortality. During the first half of
this century, the health and average life span of Americans improved
considerably, due substantially to efforts in the medical sector to reduce
infections and acute nutritional diseases. Major gains were observed in
infant and maternal mortality.
Medical care, however, may sometimes have negative health consequences.
It has been estimated that infections acquired inside the hospital strike 1.5
million of the 33 million Americans hospitalized each year, adding to hospital
costs by increasing lengths of stay and causing an additional 15,000 patient
deaths (15). Inappropriate or unnecessary treatment may also increase
mortality as well as health care costs. Risks, however, are always present
even in proper medical treatment, and in most cases they are far outweighed by
the potential benefits.
In summary , a complete program to improve health status and reduce
mortality must include environmental, lifestyle, biological, and medical care
strategies. Too much emphasis in one area may, however, involve substantial
opportunity costs due to neglect of other areas. For example, expenditures
for genetic research, for environmental protection, or to improve substandard
housing and below-poverty-level incomes could potentially have higher long run
health payoffs than would the same amount expended just for medical care. The
rise of heart disease and cancer as major killers is closely linked to changes
in the economic environment, and medical treatment or attempts to modify
individual behaviors are not by themselves likely to control these diseases.
Sedentary occupations, increasing incomes and therefore food consumption
(particularly of foods high in animal fat) , and drinking and smoking
associated with stresses placed on the family and other primary support
1-13
institutions in a highly mobile society all underlie the rise in heart
disease. The spiral of post-WWII economic production and increasing use of
automobiles have led to more and more carcinogens in the air, water, and food.
Cancer control is such a difficult policy area precisely because cancer
prevention will require fundamental changes in the physical and therefore
economic environment. Policies aimed at improving the medical treatment of
cancer victims are probably easier to implement, but they do not deal with the
basic problem. Successful strategies to deal with these and other leading
causes of mortality must modify the basic causes of our modern ills.
1-14
Risk Factors
Risk factors particular to each cause of death are discussed in separate
sections of this volume, but there are some factors common to a number of
different causes of death and these factors are summarized here.
Two of the most pervasive factors contributing to U.S. mortality from
various causes are high blood pressure and cigarette smoking . Higher levels
of blood pressure have been shown to be associated with death from all
cardiovascular diseases, diabetes mellitus, and cirrhosis of the liver
(17,18). Most cases of high blood pressure are amendable to treatment;
however many people either are not aware that they have high blood pressure or
will not maintain the proper weight, diet, and medication regimen to control
it.
Cigarette smoking contributes to death from a large number of causes (17-
22) . A recent report by the U.S. Surgeon General (22) concludes that smoking
is a major cause of lung cancer and of cancers of the larynx, oral cavity, and
esophagus; that it is a contributory factor in the development of cancers of
the bladder, pancreas, and kidney; and that approximately 30 percent of all
cancer deaths are attributable to cigarette smoking. It has also been
reported as a contributor in the development of chronic bronchitis and
emphysema, pulmonary heart disease, myocardial infarction, aortic aneursym,
and a wide variety of other vascular diseases. Smoking has important
interactions with other factors. "It is now clear that smoking may act
synergistically with ionizing radiation or asbestos to produce cancer of the
upper respiratory and digestive tracts, with oral contraceptives to produce
myocardial infarction, and probably with several dietary factors to produce
both cancer and vascular disease". It may be that the low tar, low nicotine
cigarette is less liable to cause lung cancer and chronic bronchitis, but no
1-15
less liable to produce vascular disease because of its carbon monoxide
content. A substantial reduction in smoking -related disease and death is
likely to come about only if a substantial number of smokers quit smoking.
(19)
Diet also has an important impact or certain causes of mortality. Over-eating
may lead to obesity , which contributes to high blood pressure,
diabetes, and cardiovascular disease. Diabetes is itself a risk factor for
stroke and other cardiovascular diseases. In addition, the content of our
moderr diet has important consequences for mortality. "Compared with our
ancestors' diet, that consumed by present-day western populations is higher in
intake of energy, of protein (especially animal protein), and of fat
(especially animal fat), but lower in intake of fibre-containing cereal foods;
this diet is associated with high rates of morbidity and mortality from
degenerative diseases" (23). In particular, decreased intake of animal fat
and protein, cholesterol, salt, sugar, and alcohol is recommended . Eyer (18)
suggests, however, that reduction of animal fat in the diet may just
redistribute cardiovascular deaths from coronary heart disease to stroke, and
that reducing the total level of cardiovascular disease depends on reducing
smoking and high blood pressure.
Heavy alcohol consumption carries a risk of premature death greatly
exceeding normal expectancy (24,25). "Vtfiile the lifestyle typical of many
heavy drinkers contributes to this risk, the effects of alcohol per se account
for a substantial part of the excess mortality" (24). In two Chicago studies,
heavy drinkers had higher mortality from all causes, cardiovascular diseases,
coronary heart disease, and sudden death, than could be entirely explained by
their blood pressure, smoking, and weight (25). The mortality experience of
1-16
moderate drinkers, however, does not seem to differ notably from that of life-long
abstainers (24).
Mental disease may also increase mortality risk. One study (26) found
that schizophrenic, manic, and depressive patients had a significant increase
in mortality risk over that experienced by the general population of which the
study group was a part. Mortality of a control group did not differ
significantly from that of the general population. Better diagnosis and
treatment of persons with mental diseases could help reduce the level of
mortality.
Social class has a very strong impact on mortality (12,20,27). "Social
class gradients of mortality and life expectancy have been observed for
centuries, and a vast body of evidence has shown consistently that those in
the lower classes have higher mortality, morbidity, and disability rates"
(12). The higher morbidity rates in lower status groups is an important
observation since it indicates that their excess mortality is not merely
attributable to a higher case fatality rate but is accompanied also by a
higher prevalence of morbidity. Differences between white and nonwhite
mortality rates can be attributed largely to social class differences.
Persons in lower socioeconomic groups live in a more toxic, hazardous, and
non-hygienic environment resulting in a broad array of disease consequences.
Low education contributes to poor health practices and low income affects many
aspects of health, including proper nutrition. Higher stress levels and
differences in coping with stress also contribute to higher mortality among
the poor (9, 12). Lower class persons generally receive less adequate medical
care, though this probably does not account for a major portion of the social
class differences in morbidity and mortality (12). Syme and Berkman (12)
conclude that to reduce excess mortality among the poor " new
1-17
approaches must be explored emphasizing the primary prevention of disease in
addition to those approaches that merely focus on treatment of the sick. It
is clear also that such preventive approaches must involve community and
environmental interventions rather than one-on-one preventive encounters."
The male sex is another important factor associated with higher
mortality. Males have higher mortality than females beginning at conception
and this differential continues for every age group. A high ratio of males to
females at conception declines to about 104:100 at birth until by age 70
females outnumber males approximately 3:2. In the United States, the male
age-adjusted death rate is about 50 percent higher than that for females (28).
Diabetes is the only major killer for which higher death rates are reported
for women than men, a result due entirely to higher female rates at older
ages. While there is a significant biological component contributing to
higher male mortality (29), and in particular female hormones may lower the
risk of coronary heart disease, Waldron (11) and others (12) have concluded
that sex differences in behavior are a more important cause of higher male
mortality than are inherent sex differences in physiology. "Each of the
factors which we have identified as a major contributor to men's excess
mortality involves a behavior which is more socially acceptable for males than
for females, for example, aggressive competitiveness, working at physically
hazardous jobs, drinking alcohol and, especially in the early part of the
century, smoking cigarettes. The sex differential in smoking and alcohol
consumption seems also to be linked to underlying attitudes, such as
rebelliousness and achievement striving, which are fostered to a greater
extent in males" (11). Waldron estimates that one-third of the difference
between male and female death rates may be due to men's higher cigarette
1-18
smoking, with the major contribution via increased coronary heart disese, lung
cancer, and emphysema.
If in fact much of the sex difference in mortality is not due to
biological factors, then substantial reductions in men's excess mortality can
be achieved by cultural and behavorial changes. Social and lifestyle changes
may also help to reduce female mortality. With the transition earlier in this
century from infectious to degenerative diseases as the major causes of death,
lifestyle became more important in affecting mortality experience, and the
difference between male and female mortality rates increased steadily. In the
1970's, however, this increase slowed and female mortality relative to male
mortality actually worsened for several age groups and for several leading
causes (30). This may be associated with increased smoking (19) and the
adoption of other "male" behaviors by women as job participation and mobility
increase and traditional roles are modified.
A number of risk factors have been reviewed that bear on many causes of
death, and efforts to reduce excess mortality must involve consideration of
these important precursors.
1-19
North Carolina Mortality Highlights
• Life expectancy at birth has continued to increase reaching 70.0
years for white males, 78.5 years for white females, 63.6 for
r.onwhite males, and 73.4 for nonwhite females in 1980. However,
since 1960 life expectancy at birth has increased by about 3 years
for white males and females, 4 years for nonwhite males, and 7 years
for nonwhite females. Cveral 1 , the median age at death in 1981 was
70.4 years, up from 66.4 in 1970 and 28.1 in 1914 when N.C. deaths
were first centrally recorded.
• A total of 49,212 North Carolinians died in 1981. By race and sex,
the deaths per 1000 population were slightly higher for nonwhites
than whites (by 4%), but significant! y higher for males than females
(by 34%).
• Infant mortality declined in the past 10 years reaching 13.2 deaths
per 1000 live births in 1981, from 24.1 in 1970. But despite this
dramatic improvement, North Carolina's rate continues to rank among
the highest in the nation; only 7 states had a higher rate in 1981.
• Age-adjusted mortality rates show wide gaps in the overall risk of
mortality for North Carolina males versus females and nonwhites
versus whites. In the 1979-81 period, the male rate for both races
was nearly double the female rate, and the nonwhite rate for both
sexes remained more than 40 percent above the white rate.
• Comparison of the 1981 N.C. age-race-sex-specific mortal ity rates
with provisional rates for the U.S. during 1981 reveals the
following excesses in North Carolina:
White males: Ages 55-64 (15% above U.S. rate)
White females: Ages 5-14 (23% above U.S. rate)
1-20
Nonwhite males: Ages 35-44 (31%), 45-54 (30%), 55-64 (18%),
65-74 (10%), 75-84 (14%)
Nonwhite females: Ages 0-4 (10%), 45-54 (14%)
Even after adjusting for age, race, and sex the eastern counties,
especially the northeastern counties, seem to have consistently
higher mortality rates. Based on adjusted rates, statistically
significant spatial clusters exist in eastern North Carolina for
total mortality, heart disease, stroke, motor vehicle accidents,
infant mortality, total cancer, lung cancer, and cancer of the
colon, rectum, and anus.
The highest overall age-adjusted mortality rate for nonwhites is in
the Southern Piedmont HSA while the highest age-adjusted rate for
whites is in the Cardinal and Eastern HSAs. Further, race and sex
ratios show that race differences in age-adjusted rates are greater
in the western part of the state and sex differences are greater in
the east.
Based on the number of North Carolina deaths, the 10 leading causes
in 1981 were (in descending order) heart disease, cancer,
cerebrovascular disease, accidents, pneumonia/influenza, chronic
obstructive lung disease, diabetes, suicide, chronic liver
disease/cirrhosis, and homicide. However, based on the number of
years of life lost prematurely for each cause, the 10 leading causes
were heart disease, cancer, accidents, suicide, homicide,
cerebrovascular disease, chronic liver disease/cirrhosis,
pneumonia/influenza, chronic obstructive lung disease, and diabetes.
Although age-adjusted homicide rates have declined for each race-sex
group, this rate remains substantially higher for nonwhite males.
1-21
In 1981 about 40 percent of all homicide victims were nonwhite
males; yet nonwhite males represented less than 12 percent of the
total population.
Nonwhite males have a greater risk of death from motor vehicle
accidents at every age interval except the 15-24 age group where
white males have the highest rate.
Comparing the U.S. and N.C. unadjusted rates, mortality conditions
in N.C. do not appear to be greater except in the case of
cerebrovascular disease, nephritis/nephrosis, and accidents.
However, adjusting for the state's more youthful age structure,
mortality conditions in N.C. appear much less favorable with only a
slight advantage in the case of cancer, chronic obstructive lung
disease, and chronic liver disease/cirrhosis. Based on 1979 age-adjusted
rates, even those advantages appear limited to females,
with N.C. males of both races experiencing above-average risk in
nearly every cause category.
Cancer mortality appears to be rising faster in N.C. than in the
U.S. In the last two years, the state's age-adjusted cancer death
rate has risen about 2.5% (vs. 0.9% nationwide) with notable
increases for cancer of the pancreas (19%) and cancer of the cervix
uteri (26%).
The former downward trend for cervical cancer appears to have
stalled in recent years. Based on age-specific number of deaths
from cervical cancer, there has been considerable random fluctuation
with a sharp nonwhite drop in 1979 involving all age groups. Only
for white women 55-64 has any consistent pattern of increase
recently occurred.
1-22
•
Both the state and the U.S. have recently experienced increases in
pneumonia/influenza and chronic obstructive lung disease death
rates. N.C.'s decreases in cardiovascular and accident mortality
also reflect national trends, although 1979 to 1981 reductions in
the risks of motor vehicle and other accidents were greater in the
U.S. than in North Carolina.
1982 PROVISIONAL DATA
Provisional North Carolina data show that the unadjusted rate for
all deaths declined from 325.6 deaths per 100,000 population in 1981
to 807.0 in 1982. Cancer and chronic obstructive pulmonary disease
appear to be the only causes with a rate increase in 1982.
1-23
Premature Mortality in North Carolina
Since deaths were first centrally recorded in North Carolina, the leading
causes of mortality have been ranked primarily according to number of deaths.
North Carolina deaths in 1981 have been ranked in Table A for each race-sex
group based on this traditional method. As shown, heart disease, cancer, and
stroke (cerebrovascular disease) are the leading causes of death for each
group, but the rankings of the other causes, as well as the size of the rates
for the same cause, vary among the four groups.
Rankings based only on number of deaths, however, do not necessarily
indicate where medical and public health intervention strategies can most
effectively be employed. Since death is postponable but not preventable,
age at death is a very important factor to consider. Prevention of a death
that would otherwise occur early in life could be assigned higher priority
than prevention of a death later in life. A convenient method of ranking
causes of death that incorporates age at death is by "years of life lost" (6).
If the average life expectancy at birth for white males, for example, is 70
years, a death at age 65 would mean 5 years of life lost (on the average),
while a death at age 40 would mean 30 life-years lost. An infant death
results ir. 70 years of life lost, whereas, deaths at age 70 and over do not
contribute to "life-years lost" for white males. Based on 1979-80 life tables
for North Carolina (16), the life expectancies used here to calculate years of
life lost were 70 for white males, 79 for white females, 64 for ronwhite
males, and 73 for nonwhite females. For each death in a given cause group,
age at death was subtracted from the appropriate life expectancy and all of
these life-years lost were then summed up for that race-sex group, with deaths
over the specified ages not counted. A rate of years of life lost per 100,000
1-24
population was then calculated for ranking the causes of death, so that
comparisons can be made across race-sex groups.
A more accurate method of calculating years of life lost may be to use an
average expected remaining years of life for each age of death rather than an
average life expectancy at birth. This method was considered too complicated
for the present application, and probably would not result in rankings
substantially different from those in Table B. It would place somewhat less
emphasis on infant mortality since more years of life lost would be generated
for the causes listed in Table B.
Table B displays the leading causes of death ranked according to years of
life lost per 100,000 population. Heart disease and cancer are still very
important causes of death from this perspective, but other causes become much
more prominent than before. Motor vehicle accidents account for more years of
life lost for nonwhite males than any other cause, and the general seriousness
of motor vehicle accidents as a life and health hazard is clearly shown in
this table. Cancer becomes a much more important cause of death relative to
heart disease from this perspective, since cancer decedents are about ten
years younger on the average than are heart disease decedents. In fact,
cancer accounts for more years of life lost for white females than any other
cause. Infant deaths in 1981, about 8% of which are counted under causes
(such as accidents) shown in Table B, accounted for 1322 years of life lost
per 100,000 total population (compare column 1 of Table B) and therefore
should be a key target for prevention.
1-25
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OCLC number | 4242828 |