Benazepril slows progression of renal dysfunction in patients with non‐diabetic renal disease

AIM: The present study examined the effects of benazepril, an angiotensin-converting enzyme inhibitor, on the progression of renal insufficiency in patients with non-diabetic renal disease. METHODS: Fifteen patients with non-diabetic renal disease whose serum creatinine (Cr) ranged from 1.5 to 3.0 mg/dL were given either benazepril (2.5-5 mg) or placebo once daily for 1 year in a random crossover manner. In both periods, antihypertensive medications were increased if blood pressure was greater than 130/85 mmHg. Blood sampling and urinalysis were performed bimonthly throughout the study period. RESULTS: Blood pressure was similar when comparing the benazepril and the placebo periods (128+/-12/83+/-6 vs 129+/-10/83+/-7 mmHg). Serum Cr significantly increased from 1.62+/-0.18 to 1.72+/-0.30 mg/dL (P=0.036) during the placebo period, while there was no statistically significant increase in serum Cr during the benazepril period (from 1.67+/-0.17 to 1.71+/-0.27 mg/dL). The slope of decrease of the reciprocal of serum Cr was steeper in the placebo period than in the benazepril period (-0.073+/-0.067 vs-0.025+/-0.096/year, P=0.014). Urinary protein excretion was lower during the benazepril period than during the placebo period (0.57+/-0.60 vs 1.00+/-0.85 g/gCr, P=0.006). Serum K was significantly higher in the benazepril period than in the placebo period (4.4+/-0.5 vs 4.2+/-0.5 mEq/L, P<0.001), but no patient discontinued benazepril therapy as a result of hyperkalemia. CONCLUSION: Long-term benazepril treatment decreased the progression of renal dysfunction in patients with non-diabetic renal disease by a mechanism that is independent of blood pressure reduction.