Education, genetic ancestry, and blood pressure in African Americans and Whites.

OBJECTIVES

We assessed the relative roles of education and genetic ancestry in predicting blood pressure (BP) within African Americans and explored the association between education and BP across racial groups.

METHODS

We used t tests and linear regressions to examine the associations of genetic ancestry, estimated from a genomewide set of autosomal markers, and education with BP variation among African Americans in the Family Blood Pressure Program. We also performed linear regressions in self-identified African Americans and Whites to explore the association of education with BP across racial groups.

RESULTS

Education, but not genetic ancestry, significantly predicted BP variation in the African American subsample (b=-0.51 mm Hg per year additional education; P=.001). Although education was inversely associated with BP in the total population, within-group analyses showed that education remained a significant predictor of BP only among the African Americans. We found a significant interaction (b=3.20; P=.006) between education and self-identified race in predicting BP.

CONCLUSIONS

Racial disparities in BP may be better explained by differences in education than by genetic ancestry. Future studies of ancestry and disease should include measures of the social environment.