Systolic blood pressure levels in black populations in sub-Sahara Africa, the West Indies, and the United States: a meta-analysis.

Average systolic blood pressure levels from epidemiological studies conducted on black populations in sub-Sahara Africa were pooled and compared with pooled systolic blood pressure levels from black populations in the northern portion of the Western hemisphere (the West Indies and the United States). Studies published in English that listed systolic blood pressure means and standard deviations and sample sizes in 40-49-year-old men and women were included. Overall, systolic blood pressure levels were higher (p less than 0.05) in blacks from the northern Western hemisphere than in blacks from sub-Sahara Africa for both men (12 mm Hg higher) and women (13 mm Hg higher). The analysis was also conducted on regions within sub-Sahara Africa and in rural and urban subgroups. Systolic blood pressure was lower (p less than 0.05) in East Africa than in the other three regions within Africa for both sexes. Overall, urban blacks within Africa had higher systolic blood pressures (p less than 0.05) than rural blacks for both sexes. In the northern Western hemisphere, rural blacks had higher systolic blood pressures (p less than 0.05) than urban blacks for both sexes. Studies should be designed with standardized methods to unravel these intraracial differences in blood pressure levels.