Epidemiology of cardiovascular mortality-geographic and ethnic

Heart Disease

There has been a continuing debate among health professionals concerning the appropriate strategy of use for the prevention of ischemic heart disease: a targeted high-risk group strategy or a community strategy. A careful review of the evidence demonstrates that neither approach can be recommended to the exclusion of the other. The results are, however, supportive of the lowering of serum cholesterol in high risk individuals. The inconclusiveness of these studies appears to be related to several problems, which are discussed in the text: statistical powerproblems, characteristics of the interventions, unique design problems associated with prevention trials, and problems related to the choice of modelsfor investigation and intervention. Several suggestionsforfuture research to address each of these problems are made.

Hypertension prevalence and the status of awareness, treatment, and control in the Hispanic Health and Nutrition Examination Survey (HHANES), 1982-84

The prevalence rates of hypertension among adult (ages 18-74) Mexican Americans, Cuban Americans, and Puerto Ricans were estimated using data from the 1982-84 Hispanic Health and Nutrition Examination Survey (HHANES). Hypertension is defined as diastolic greater than or equal to 90 mm Hg, or systolic greater than or equal to 140 mm Hg, or currently taking antihypertensive medication. Among Mexican Americans in the Southwestern United States, 16.8 percent of the males and 14.1 percent of the females were found to be hypertensive. Among Cuban Americans in Dade County, Florida 22.8 percent of the males and 15.5 percent of the females were hypertensive. Among Puerto Ricans in the New York City area 15.6 percent of the males and 11.5 percent of the females were hypertensive. The age-adjusted rates are significantly lower than comparable rates for Whites and Blacks as measured in the second National Health and Nutrition Examination Survey (NHANES II), 1976-80. Control of hypertension in the HHANES populations fall short of the 1990 Objectives for the Nation established by the US Public Health Service 60 percent (34 percent controlled Mexican American hypertensives, 27.8 percent controlled Cuban American hypertensives, and 29 percent controlled Puerto Rican hypertensives.

Sex differentials in cardiovascular mortality: an ecological analysis

The objective of this study is to explain spatial variations in cardiovascular mortality by sex. Recognizing the interdependence of the various dimensions of the 'ecological complex', it is maintained that spatial variations in cardiovascular mortality by sex and the sex differentials in cardiovascular mortality are the consequences of environmental, sustenance organization, health technology, and demographic factors. The test of the model is based on U.S. county level cardiovascular mortality data for ages 25-65 for the period 1970-1980. The most distinctive feature of the results is that environment has the greatest impact on sex differentials in cardiovascular mortality followed by sustenance organization. In this regard, socioeconomic status is shown to be the single most important variable in explaining cardiovascular mortality rates for both sexes in most community types. The effect of health technology is not significant, and increased availability of health manpower and facilities are often found in conjunction with higher rates of cardiovascular mortality for both sexes. The results of this study confirm the importance of programs directed toward altering the basic environment and sustenance organization structures of communities rather than other ecological components such as health technology.

Patterns of mortality from selected causes in an urban population

Mortality data for selected non-cancer causes for the period 1974-1980 were analyzed for the City of Philadelphia to examine spatial patterns. Four categories of conditions--ischemic heart disease (including acute myocardial infarction), chronic liver disease and cirrhosis, cerebrovascular disease, and external causes--demonstrated significant variation in death rates. Moreover, neighborhoods with high levels of mortality for these conditions appeared in significant clusters. With the exception of ischemic heart disease, neighborhoods with high levels of mortality were characterized by below average levels of SES. A group of predominantly black neighborhoods in the central part of the city had extremely high rates for five or more of the nine causes investigated in this paper. In an earlier analysis, all but one of these neighborhoods were found to have the highest level of overall cancer mortality. These findings support the hypothesis that there are social and behavioral factors that are associated with a wide range of disease conditions, and many of these factors are associated with socioeconomic status.

Geographical patterns of heart disease in the Northeastern United States

A 49-county region surrounding the urban corridor from New York through New Jersey to Philadelphia was the focus of an investigation of the spatial patterns of mortality from four types of heart disease: major cardiovascular, acute ischemic, chronic ischemic and cerebrovascular. The data used were age-adjusted mortality rates for white males and white females for the period 1968-1972. Central to the research was interest in the existence of county clusters with similar rates, high and low risk areas and possible associations of mortality rates with environmental and socioeconomic conditions. The tasks completed in this first phase of a projected multi-phase project led to the identification of four country clusters within the region. High major cardiovascular rates appear to make the Southern New Jersey cluster a high risk zone. In contrast, a Central Corridor cluster has relatively low rates for all the diseases. No clear pattern was in evidence for the Northwestern Periphery cluster. Finally, a stark contrast between acute and chronic ischemic rates appeared in the Urban Spur. The next step in this research will be to search for either consistency or deviation from these patterns in the 1973-1976 period. A risk factor data set will be created to analyze the patterns in greater detail.

Three-area epidemiological study of geographic differences in stroke mortality. I. Background and methods

An epidemiological study was conducted to determine the geographical variations in stroke mortality among three U.S. areas. They were Savannah, Georgia (high stroke rates), Hagerstown, Maryland (intermediate stroke rates) and Pueblo, Colorado (low stroke rates). In each area samples were drawn of the population in the 35--54 age group. The subjects were interviewed and examined to obtain the information required on medical conditions and/or living habits which would characterize each area. A brief medical and family history, as well as demographic and personal data, were obtained by interview. The medical examination included blood pressure, ECG, blood and urine chemistry, height and weight. In all three cities the response rate in the final sample selected was 90% (2,375 individuals) interviewed and 74% (1.939 individuals) examined.

Attributable risk, population attributable risk, and population attributable fraction of death associated with hypertension in a biracial population

In 1961, blood pressure was measured in the 40-69-year-old segment of the population of Evans County, Georgia. Mortality was monitored for up to ten years. The relationship found between hypertension and mortality is characterized in this report by four parameters: attributable risk, prevalence, population attributable risk, and population attributable fraction. Attributable risk of death, a measure of the over-all impact of hypertension on those in each race-sex group with hypertension, is high in white males, black males, and black females, and is lowest in white females. Population attributable risk, a measure of the impact of hypertension on each entire race-sex group, is highest in black males and females due to the high prevalence of hypertension in blacks. It is somewhat lower in white males and lowest in white females. The fraction of all deaths attributable to hypertension (population attributable fraction) is highest in black females and lower in the other three groups. The population attributable fraction (ranging from 0.26 to 0.54 for systolic hypertension) is of such magnitude that if the 50% reduction in mortality achieved in the Veteran Administration Cooperative Study could be repeated in the general population, life expectancy after 40 years of age could be substantially increased.

Heart disease mortality among black migrants: a study of Ohio residents (1960-1967)

In a demographic study, the black Ohio residents were characterized by those born in Ohio and those born in other regions of the United States, and comparisons were made of rates for all deaths (1960-1967) for coronary heart disease (420), endocarditis and myocardial degeneration (421-422), hypertensive cardiovascular diseases (440-447), cerebrovascular diseases (300-334), cardiovascular diseases (400-468), and total diseases of the cardiovascular system (300-334) (400-468). The division of the total United States-born Ohio residents by region of birth provided marked differences in the age-adjusted rates in the relative comparisons. The black males and females born in the South had a markedly higher age-adjusted death rate (ages 45 to 64) than those born in Ohio in each of the categories of cardiovascular diseases studied. For coronary heart disease, the age-adjusted death rate for the black males showed a marked excess over the black females, for each region of birth, whereas for hypertensive cardiovascular diseases the black males and females had similar age-adjusted rates for each region of birth. The findings indicate a carry-over among the black of a higher cardiovascular risk among those born in the South and lend support to the concept of the influence of the endemic factors in the early years of life. In the prospective study of black steelworkers, it was observed that migrant and nonmigrant workers had approximately the same mortality for cardiovascular disease overall, and when specific work areas were considered. Selective factors of employment, of medical screening, and capability of continued employment in strenuous environments, were considered the most likely basis for the similar mortality experience.

Further inquiry into Protestant clerical mortality patterns

Clerical mortality rates in the United Presbyterian Church in the United States of America and the Lutheran Church-Missouri Synod have been studied in relation to selected social characteristics.

Overall mortality rates in the two study groups are more favourable than those for both the general US male population and for the total US white clergy. For most specific causes, the rates for the Lutherans but a high degree of similarity exists.

Possible explanations for these findings are discussed.

IV. Epidemiology and planning for the North Carolina Regional Medical Program

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Coronary heart disease and future expectation of life

Mortality from coronary heart disease (CHD) has risen enormously over the last generation. Some regard the concomitant increase in life expectancy as the sole explanation; others maintain the increases at least in part to be real. Irrespective of the true causes, the question arises: If increases in CHD mortality continue in certain of the populations most affected, may not expectation of life ultimately decrease? An answer is sought by examining relevant information (1) on a large community of rural Indians having a low prevalence of CHD, and (2) on the offspring of Indian immigrants to South Africa, whose CHD mortality now exceeds that of the local whites. It is concluded that while promotive factors linked with urbanization and prosperity are chiefly responsible, the bearing of an ethnic propensity cannot be excluded. Continuation of the present CHD mortality trend in South African Indians almost undoubtedly will decrease their life expectancy, which, even at present, appears to compare unfavorably from youth onward with that of the rural Indian group described.