EFFECTS OF BLOOD-PRESSURE CONTROL ON PROGRESSIVE RENAL-DISEASE IN BLACKS AND WHITES

African Americans (blacks) have a disproportionately high incidence of end-stage renal disease due to hypertension. The Modification of Diet in Renal Disease (MDRD) Study found that strict blood pressure contro l slowed tile decline in glomerular filtration rate (GFR) only in the subgroup of patients with proteinuria. The present report compares the effects of blood pressure control in black and white MDRD Study parti cipants. Fifty-three black and 495 white participants with baseline GF Rs of 25 to 55 ml/min/1.73 m(2) were randomly assigned to a usual or l ow mean arterial pressure (MAP) goal of less than or equal to 107 or l ess than or equal to 92 mm HE, respectively. GFR decline was compared between randomized groups and correlated with the level of achieved bl ood pressure. The mean (+/-SE) GFR decline over 3 years in the low blo od pressure group was 11.8+/-7.3 ml/min slower than in the usual blood pressure group among blacks (P=.11) compared with 0.3+/-1.3 ml!min sl ower among whites (P=.81) (P=.12 between blacks and whites). In both b lacks and whites, higher baseline urine protein excretion was associat ed with a greater beneficial effect of the low MAP goal on GFR decline (P=.02 for both races). Combining both blood pressure groups and cont rolling for baseline characteristics, higher follow-up achieved MAP wa s associated with faster GFR decline in both blacks (P<.001) and white s (P=.002), with a sevenfold stronger relationship in blacks (P<.001). These secondary analyses support the prior recommendation for a lower than usual blood pressure goal (MAP less than or equal to 92 mm Hg) i n black and white patients with proteinuria (>1 g/d). In addition, a l ower level of blood pressure control may be even more important in bla cks than in whites in slowing the progression of renal disease.