Randomly allocated study of the effects of standard therapy versus ACE inhibition on micro-albuminuria in essential hypertension.

OBJECTIVE

To compare the effects of standard therapy (diuretic, beta-blocker or both) with those of angiotensin converting enzyme (ACE) inhibition with quinapril on renal function and urinary albumin excretion in patients with essential hypertension.

METHODS

A 1-year, placebo-controlled, randomly allocated study was conducted in a group of 40 patients with essential hypertension. Before beginning the active treatment phase, all patients were given a matched placebo for quinapril for at least 14 days. At baseline and after 1, 3, 6 and 12 months of treatment, blood pressure, heart rate, body weight, renal plasma flow, glomerular filtration rate, plasma renin activity, plasma aldosterone and urinary albumin excretion were measured.

RESULTS

Both the standard therapy and quinapril produced similar decreases in blood pressure, but only quinapril produced a significant decrease in micro-albuminuria, from 68.5 +/- 16.7 to 47.2 +/- 14.9 mg/24 h (P < 0.05). The renal plasma flow remained constant in both study groups while the glomerular filtration rate and filtration fraction decreased significantly (P < 0.05) in the quinapril group.

CONCLUSIONS

The results of this study indicate that long-term therapy for essential hypertension with ACE inhibition has a more favorable effect on micro-albuminuria than standard therapy for an equal level of blood pressure control.