This study was undertaken to compare the effects of chronic
angiotensin-converting enzyme (ACE) inhibition on blood pressure (BP) and renal hemodynamics in older black and nonblack hypertensive patients with
chronic renal insufficiency. A multicenter, placebo lead-in double-blind, parallel group study was performed to compare the
antihypertensive efficacy and renal hemodynamic response to the once-daily
ACE inhibitor fosinopril (n = 14) and
lisinopril (n = 13) over a 22-week period. The study goal was to lower diastolic blood pressure (DBP) to 90 mm Hg or less.
Furosemide was added after 6 weeks if blood pressure goal was not achieved. At outpatient clinics at university medical centers, 27 older hypertensive patients (> or = 45 years; 12 blacks, 15 nonblacks; 19 male, eight female) with DBP of 95 mm Hg or higher and 4-hour
creatinine clearance 20 to 70 mL/min/1.73 m2 were studied. Changes (delta) from baseline in BP, glomerular filtration rate (GFR), and renal plasma flow (RPF) were measured. Mean systolic blood pressure (SBP) and DBP decreased significantly and to a similar extent in randomized groups:
fosinopril (mean +/- SEM) delta DBP at 6 weeks was -13 +/- 2 (P < 0.0001; 95% CI, -16 to -9) and at 22 weeks was -12 +/- 2 (P < 0.0001; 95% CI, -16 to -9);
lisinopril delta DBP at 6 weeks was -14 +/- 6 (P < 0.0001; 95% CI, -10 to -18) and at 22 weeks was -16 +/- 2 (P < 0.0001; 95% CI, -12 to -21). GFR and RPF did not change significantly in either group. BP was significantly reduced and to a similar extent in blacks and nonblacks: for blacks, delta DBP at 6 weeks was -11 +/- 3 (P < 0.05; 95% CI, -0.01 to -9) and at 22 weeks was -16 +/- 2 (P < 0.0001; 95% CI, -11 to -20); for nonblacks, delta DBP at 6 weeks was -14 +/- 1 (P < 0.0001; 95% CI, -12 to -17) and at 22 weeks was -12 +/- 2 (P < 0.0001; 95% CI, -16 to -8). Eight patients (five blacks and three nonblacks) required an addition of
furosemide after 6 weeks to reach the DBP goal of < or = 90 mm Hg at 22 weeks. GFR was not significantly altered for either racial group at 6 weeks; however, at 22 weeks; however, at 22 weeks, GFR decreased significantly in blacks (delta GFR, -16 +/- 5; P < 0.006; 95% CI, -26 to -5) and tended to increase in nonblacks (delta GFR, 7 +/- 6; P > 0.25). delta GFR correlated directly with the delta RPF (delta GFR = 0.0611* delta RPF -2.35 +; r = 0.68; P < 0.003). There was no correlation between delta MAP and delta GFR or delta RPF in blacks or nonblacks. We conclude that chronic ACE inhibition with
fosinopril and
lisinopril alone or in combination with
furosemide lowers BP in older blacks and nonblacks with
hypertension and
chronic renal insufficiency. Racial differences in the renal hemodynamic response to chronic ACE inhibition were noted and appear to be independent of
diuretic use and the magnitude of BP lowering.