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An epidemiological study was made of cerebrovascular disease in a bi-racial Southern community. The study population comprised about 3,000 men and women aged 15 to 75 years at the time of entry into the study. During the 87-month period between the initial and second examinations, 94 persons developed their first cerebrovascular event.The incidence of stroke among white men (4.7/1,000/year) was almost four times that in white women and more than twice that reported for white men in other sections of the country. The incidence rates of stroke in Negro men and women were equal (5.8/1,000/year).The risk factors predisposing to stroke in white men appeared to be severe hypertension, obesity, high hematocrit levels, and antecedent electrocardiographical abnormalities These factors were not as prominent among the other race-sex groups.The high incidence of cerebrovascular disease found in this semirural population of Georgia supports previous reports of increased mortality rates for stroke in this section of the country and represents a unique situation, the exact cause for which remains to be determined. ADDITIONAL KEY WORDS stroke morbidity risk factors race factors epidemiology ischemic heart disease• Mortality studies in the United States indicate that death rates from cerebrovascular disease are greater among Negroes than Caucasians and higher in both races in the Southeastern section of the country. Recent studies designed to authenticate these death

In a seven-year follow-up of 3,102 Evans County, Georgia, residents examined in the prevalence survey of 1960 through 1962, 143 new cases of coronary heart disease (CHD) occurred, 56 of which resulted in death during the interval. Ethnic differences in CHD among males discovered during 1960 through 1962 were again confirmed.Excess of white males could not be explained by differences in case fatality, diagnostic criteria, missed cases, or by a competing cause of death. In contrast to ethnic differences, differences by social class found in the prevalence survey among white males were not found in the incidence study. Various analyses suggested that the excess prevalence found in the high social class was a reflection of prior high incidence rates in this class. Over time these class differences are disappearing, particularly among younger men.As indicated previously,1 the prev-. alence study in Evans County, Georgia, in 1960 through 1962 had shown marked differences in cor¬ onary heart disease (CHD) by eth¬ nic group and social class. White males had an age-adjusted prevalence rate that was almost three times higher than black males (59 per 1,000 compared to 22 per 1,000). Most of this white excess was attributed to the higher social class men who had a rate of 99 compared to 40 for the lower social class. Further, no differ¬ ences were found by ethnic group for females, the rate for white females being 18 and for black females 14 per 1,000. Thus, within ethnic groups, white males had a five-fold higher rate than white females, while for blacks the ratio was only 2 to 1.The initial purpose of the incidence study was to determine whether these differences persisted when a population free of CHD was followed over time. Such an analysis would provide an indication of the extent to which the differences in prevalence in the various groups indicated differ¬ ences in risk of developing CHD as opposed to differences in selective survival or migration, or both. Fur¬ ther, it was hoped that this follow-up study might indicate whether, in the rapidly changing environment of Evans County, a secular trend in these ethnic group-social class pat¬ terns was occurring.The methods by which this study was conducted, including the com¬ pleteness of ascertainment and ex¬ amination of the members of the original 1960 through 1962 cohort and the criteria used for diagnosis of the various manifestations of CHD, are described elsewhere.2 Results Differences by Ethnic Group andSex.-The incidence of all manifesta¬ tions of definite and probable CHD for the 87-month follow-up period is shown by age, ethnic group, and sex in Table 1 and Fig 1.As can be seen from these data, the differences in males by ethnic group found in the prevalence study were confirmed, black males having lower rates at all ages than white males, with only minor differences appear¬ ing among females. The extraordi¬ narily low rates for black males in comparison to the whites was one of the most intriguing findings of this study and one for which explanations were energ...

Using prevalence data of white men in Evans County, Ga, this paper studies the relationship between coronary heart disease (CHD) and social mobility. Two basic findings are (1) that in both types of mobility, intragenerational and intergenerational, persons in the two lower social classes are more at risk if upwardly mobile than the stable populations; and (2) that upwardly mobile persons among the upper social classes show lower rates than the stable, a reversal of the other finding.One of the striking findings of the cardiovascular incidence study conducted in Evans County, Georgia, between 1960-1962 was the changing relationship between coronary heart disease (CHD) and social class that had oc¬ curred during this time period (Cassel et al, 901). Social class was assessed by the McGuire-White scale' (a rural version of the Warner scale), which uses occupation, education, and source of income to derive a social class in¬ dex score. Social class analysis was re¬ stricted to white men. In 1960 those in the upper half of the range of social class scores were found to have age adjusted rates of CHD that were more than twice as high as those with scores in the lower half of the range.By 1967, however, this social class dif¬ ference had disappeared with the "lower" social class men having the same rates as the "higher." Various analyses have convinced us that these changing relationships represent a change in incidence by social class rather than being the effects of selec¬ tive survival or migration (Cassel et al, 901). Furthermore, it would ap¬ pear that the equality in rates in the two social class groups has been achieved by an increase in the rates for the "lower" social class men (par¬ ticularly younger men), rather than a decrease in the "higher" social class.This increase in the rates of CHD in the lower social class is occurring at a time when Evans County is un¬ dergoing a fairly rapid transition from a rural agrarian to a more "modern" industrialized economy.Until comparatively recently the only people participating in this change of "style of life" to any large extent were the "higher" social class men. It was the clinical impression of one of us (Hames, 883), based upon a life¬ time of experience in this county, that in recent years "lower" social class men were beginning to partici¬ pate in these changes to an ever in¬ creasing extent. Thus, in microcosm Evans County may be recapitulating the changes in style of life and ac¬ companying CHD rates that have characterized the urban developed countries over the past half century.What those particular styles of life are, particularly those which may be relevant to the risk of developing CHD, is a matter of speculation. There is no evidence that major changes in diet have occurred. Changes in cigarette smoking and physical activity surely have occurred, but as shown elsewhere (Cassel, 890), these are unlikely to have ac¬ counted for all of these social class findings. An additional possibility that requires exploration is that some of the psychosocial fact...