¹Biostatistics, Bioinformatics and Epidemiology, Medical University of South Carolina, Charleston, SC; Medicine, Medical University of South Carolina, Charleston, SC.

Abstract

The association between obesity and hypertension is well-documented but racial differences might confound this relation. The Black Pooling Project consists of nine cohort studies and includes 8,920 black women, 7,175 black men, 27,606 white women and 37,413 white men who were followed for 8 to 30 years between 1960 and 1995. The figure shows the gender-racial specific, age- and cohort-adjusted systolic blood pressure means according to levels of body mass index (BMI). After controlling for age, cholesterol, smoking status and cohort, each unit increase in BMI is associated with an increase in SBP of approximately 0.43 mmHg in black women, 1.01 mmHg in white women, 0.29 mmHg in black men and 0.79 mmHg in white men. The racial differences are significant between men and women. While blacks have a higher systolic blood pressure than whites at all levels of BMI, the difference narrows progressively with increasing BMI. The mean systolic blood pressure for black men and women were virtually all in the hypertensive range irrespective of BMI, whereas the mean systolic BP for whites reached the hypertensive range at BMI values of >30.5 for women and >32.5 for men. These data indicate that the racial disparity in blood pressure is greatest in very lean subjects and narrows progressively with increasing degrees of overweight and obesity.