..., or chronic high blood pressure, was assessed by the authors in Africans as well as in people of African descent in the U.S. and the Caribbean. The rate dropped dramatically from the U.S. across the Atlantic to Africa (graph), and the difference was most pronounced between urban African-Americans and rural Nigerians . The findings suggest that hypertension may largely be a disease of modern life and that genes alone do not account for the high rates of hypertension in African-Americans.