Evidence for an increased risk for hypertension with centrally located body fat and the effect of race and sex on this risk.

Data from the First Health and Nutrition Examination Survey (HANES), 1971-1974, were used to examine the relationship between blood pressure and the distribution of subcutaneous body fat in 5506 survey participants, ages 30-59. Triceps and subscapular skinfolds were used as approximations of peripheral and centrally located body fat. The effects of race, sex and age on the obesity-blood pressure relationship were analyzed. Subscapular skinfold was the better predictor of both systolic and diastolic blood pressure in each race-sex group, sharing all of the association of triceps with blood pressure and having significant predictive power unshared by triceps. The slopes of regression of subscapular skinfolds with systolic blood pressure for each race-sex group were not significantly different. A 1 mm increase in skinfold thickness increased the predicted mean systolic blood pressure by 0.63 +/- 0.03 mmHg (F = 519). Mean diastolic blood pressure rose 0.43 +/- 0.02 mmHg per unit increase of skinfold in whites (F = 549), and 0.14 +/- 0.04 mmHg less in blacks (F = 13), indicating a significant racial difference. Age and subscapular skinfold contributed independently to the variability in blood pressure in each race-sex group. These results demonstrate that the blood pressure of middle-aged Americans is more directly associated with centrally deposited body fat. This finding is true across race and sex groups, and is independent of age.