Family follow-up study of serum cholesterol in Evans County, Georgia

Abstract

The similarity of serum cholesterol levels among family members was studied at baseline in 1960 and at follow-up examination 7 yr later in the Evans County cardiovascular disease cohort. The median correlation coefficient of the age-race-sex-adjusted cholesterol values was 0.3 at baseline among putative first-degree genetic relatives and was consistently higher for relationships in lower-social-class than in higher-social-class families. There was a greater increase in serum cholesterol in lower- than in higher-social-class individuals in a 7-yr follow-up. The correlation coefficient between cholesterol measurements at baseline and 7-yr follow-up reexamination was in the range of 0.6–0.7 for individuals in the different race, sex and social groups in Evans County. Parental cholesterol values at baseline were correlated with offspring values at follow-up. These follow-up correlation coefficients were largest for lower-social-class and farming families, in whom the similarity persisted into the adulthood of the offspring. The observations are consistent with shared behavioral and environmental familial determinants of serum cholesterol selectively transmitted to offspring in different social and occupational strata of Evans County.