Blood pressure differences between blacks and whites in relation to body size among US children and adolescents

No large national studies of ethnic differences in blood pressure among chi ldren accounting for body size differences have been published, to the auth ors' knowledge. This report details the similarities and differences in sys tolic and diastolic blood pressures between Black children and White childr en in the United States and examines the effects of age, sex, and body size on ethnic differences in blood pressure levels. Standardized measurements of seated systolic and diastolic pressures from eight large epidemiologic s tudies published between 1978 and 1991 that included measurements of 47,196 children on 68,556 occasions for systolic pressure and for 38,184 children on 52,053 occasions for diastolic pressure were used; 51 percent (24,048 c hildren) were boys and 37 percent (17,466 children) were Black. Overall, th ere appear to be few substantive ethnic differences in either systolic or d iastolic pressure during childhood and adolescence. The differences that we re observed were small, inconsistent, and often explained by differences in body size. There was an ethnic group-body mass index (BMI) interaction tha t resulted in these findings that at lower levels of BMI Blacks have higher blood pressure and more hypertension than do Whites, but that at the highe st levels of BMI, Whites have more hypertension (systolic or diastolic pres sure) than do Blacks.