The excess risk of treated end-stage renal disease in blacks in the United States.

Analysis of national data from the United States Renal Data System for 1988 revealed an important joint effect of age and race in determining the higher risk of ESRD for blacks as compared with whites. For adults, both hypertension and diabetes made important contributions to the combined effect of age and race. In contrast, glomerulonephritis was not considered to be an important contributor to this joint effect. The combined effect of gender and race was weaker than that of age and race; however, among blacks, differences in the proportions of ESRD attributed to hypertension and diabetes across gender were observed. The age-race joint effect is consistent with the hypothesis that a combined effect of lack of treatment and aging on the process that leads to ESRD may play an important role in the excess risk for ESRD among blacks.