Angiotensin-converting enzyme inhibitors (ACEI) have proved an antihypertensive and renoprotective effect with reduction of proteinuria in diabetic and non diabetic nephropathy, but not exempt of side effects in advanced chronic kidney disease (ACKD) patients. Angiotensin receptor blockers (ARB) have emerged as antiproteinuric, renoprotective and cardioprotective therapy. Only a few reports have been published studying ARB effects on non-diabetic ACKD patients. Our aim is to study Irbesartan (ARB) on non-diabetic ACKD patients and compare its effects with ACEI.
Patients and methods: Forty three non-diabetic patients at ACKD stage IV NKF-DOQI (CrCl <30 ml/min) were enrolled in a prospective study. Group I: 21 received Irbesartan monodose 150-300 mg/day (63+/-17 y/o, 12 F, 9 M,ClCr 22.1+/-8 ml/m.), Group II: 22 received ACEI (65+/-13 y/o, 8 F, 14 M, CrCl 22.3+/-7 ml/m). Parameters studied: blood pressure (BP), pulse pressure (PP), renal function (CrCl), proteinuria (in patients with proteinuria >or= 0.5 g/d), serum K+ and serum uric acid, at month 0, 3, 6, 9 and 12.
Results: At 12 months, BP was controlled in 57% of Group I vs 39% of Group II. Mean systolic BP was decreased from 154/85 to 138/77 in G I, and from 146/85 to 133/77 in GII, with a decrease in 10.7% of mean BP in GI and 8.5% in GII (NS). Irbesartan reduced PP in 7.2% vs 8.3% with ACEI (NS). CrCl reduction with Irbesartan was 0.23 vs 0.21 ml/min/month with ACEI (NS). The antiproteinuric effect was higher with Irbesartan (from 2.1 to 1.3 g/day) vs. ACEI (from 1.35 to 1.33 gr /day), being statistically significant the reduction percentage between the two groups (p >or= 0.041). Serum K+ level do not change in Irbesartan group and increased 10% in ACEI group (p<0.001). Uric acid was decreased by Irbesartan in 17% and increased in 4% by ACEI (p<0.001).
Conclusions: Irbesartan in non-diabetics patients with advanced chronic renal disease, compared with ACEI showed similar blood pressure control and similar effect on chronic kidney disease progression, with higher antiproteinuric effect. On the other side, Irbesartan showed a reduction of serum uric acid, and did not increase serum K+ levels.