Effect of Angiotensin Converting Enzyme Inhibition by Perindopril on Proteinuria of Primary Renal Diseases

Many primary renal diseases are associated with marked proteinuria resistant to immunosuppressive therapy. Short-term treatment with angiotensin converting enzyme (ACE) inhibitors may decrease proteinuria in these patients, but the long-term effect of these agents on urinary protein excretion is not known. We conducted a double-blind, parallel-design, placebo-controlled study of 1 year duration to evaluate the efficacy of the new ACE inhibitor, perindopril, in reducing proteinuria in patients with nephrotic syndrome due to histologically proven membranous and membranoproliferative glomerulonephritis and focal segmental glomerulosclerosis. Half of the patients treated with perindopril displayed a decrease in urinary protein excretion from 6.1 +/- 1.0 to 1.2 +/- 0.5 g/24 h, and a rise in serum albumin levels. In the placebo group, protein excretion increased modestly and serum albumin level did not change. There was no difference between the responders and nonresponders to perindopril in age, blood pressure, level of creatinine clearance or urinary sodium excretion. However, the degree of proteinuria before treatment with perindopril was significantly (p0.01) higher in the nonresponders. In 3 patients in whom the treatment with perindopril was extended for 18-24 months, urinary protein excretion remained below 1 g/24 h. The data show that perindopril: (1) is an effective agent in the treatment of proteinuria of primary renal diseases; (2) the effect is sustained for up to 2 years if the administration of the drugs is maintained, and (3) this action of perindopril does not depend on the level of sodium intake.