Effects of benazepril and nicardipine on microalbuminuria in normotensive and hypertensive patients with diabetes*

Abstract

Diabetic nephropathy is the most frequent cause of chronic renal failure. The onset of microalbuminuria in patients with diabetes mellitus, which seems to be related to blood pressure and the control of glycemia, is predictive of the development of true proteinuria. This multicenter, single-blind, randomized study examined the effects of benazepril and nicardipine on overnight microalbuminuria in 57 normotensive and 46 hypertensive diabetic patients. At the end of a 3-month placebo run-in period, the patients were stratified on the basis of the presence or absence of arterial hypertension and, within each stratum, randomized to receive one daily tablet of 10 mg benazepril or one tablet of 20 mg nicardipine twice daily for 6 months. Renal hemodynamics was investigated in 25 patients. Both drugs decreased overnight microalbuminuria throughout the study period, but benazepril was more effective than nicardipine (p = 0.025); in the patients with hypertension, both drugs led to a similar marked reduction in systolic and diastolic blood pressure. This study shows that benazepril was more effective than nicardipine in reducing overnight microalbuminuria in patients with diabetes mellitus, independently of their antihypertensive properties.

Comparing the Efficacy of Angiotensin Converting Enzyme In-hibitors with Calcium Channel Blockers on the Treatment of Di-abetic Nephropathy: A Meta-Analysis

“…Only one trial reported random sequence generation (14). One trial reported the method to generate the allocation sequence (15) (Fig. 1A and B).…”

“…The test for heterogeneity was low ( P =0.73, I 2 =0%). Three papers (15, 19, 20) reported urine albumin excretion rate. The change in urine albumin excretion rate related outcome was not significantly different between the two treatment arms (MD=1.91μg/min; 95% CI: −10.3 to 14.12; P =0.76, Fig.…”

Antihypertensive and organ-protective effects of benazepril

“…ACE inhibitors including benazepril showed beneficial effects in terms of reducing decline in GFR and the requirement for dialysis compared with ARB treatment in a long-term study in nondiabetic patients [117]. Benazepril and the CCB nicardipine demonstrated similar antihypertensive effects in diabetic patients; however, benazepril was more effective in reducing overnight microalbuminuria (p = 0.025) [118]. These findings are supported by further studies that have shown that use of a CCB alone does not slow progression of renal disease to the same extent as renin-angio tensin-aldosterone system antagonists, despite producing similar reductions in BP [119,120].…”

Reduction of ACE Activity Is Insufficient to Decrease Microalbuminuria in Normotensive Patients With Type 1 Diabetes

“…Numerous reports have proved that treatment with ACE inhibitors reduces the urinary albumin excretion rate (UAER) in this particular category of patients (2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16). However, many of these trials were of rather short duration or contained only a small number of patients (2)(3)(4)(5)(6)(7)(8). When the effect of ACE inhibitors on UAER has been compared with that of other antihypertensive drugs, a more profound reduction has often been achieved with ACE inhibition (2,7,8,10).…”

“…However, many of these trials were of rather short duration or contained only a small number of patients (2)(3)(4)(5)(6)(7)(8). When the effect of ACE inhibitors on UAER has been compared with that of other antihypertensive drugs, a more profound reduction has often been achieved with ACE inhibition (2,7,8,10). Demonstration of a reduction in UAER, even after correction for changes in blood pressure (BP) (17), and two large studies of the short-acting ACE inhibitor captopril (9,11) also implicate that pharmacological inhibition of ACE confers renoprotective effects that are independent of changes in BP in normotensive patients with type 1 diabetes.…”