THE PROGRESSION RATE OF CHRONIC-RENAL-FAILURE WITH HYPERTENSION AND PROTEINURIA CAN BE SLOWED BY TREATMENT WITH ANGIOTENSIN CONVERTING ENZYME-INHIBITORS

We compared the progression rate of chronic renal failure in 62 patients with serum creatinine in the narrow range of 3.5 to 4.5 mg/dl, hypertension, and proteinuria (1 to 17 gm/day). Patients were divided into two treatment groups: 31 were treated with an angiotensin converting enzyme inhibitor (ACEI) and 31 were treated with a calcium antagonist during 3 years of follow-up. All patients followed an identical low-protein, low-phosphate diet with normal sodium intake. All had stable drug-controlled blood pressures. The evolution of renal failure was defined as progressive if serum creatinine exceeded 20% of the initial value, and stable otherwise. After the second year, we observed progression in 51.6 +/- 9.6% of the ACEI group versus 78.7 +/- 8.8% in the calcium antagonist group. The difference between the survival-to-failure curves of the two treatment groups by univariate analysis was only marginally statistically significant (P = 0.05). We also evaluated the survival-to-failure curve of renal function by multivariate survival analysis, considering six predictors: protocol drug, proteinuria, mean blood pressure, serum creatinine, sex, and age of patients. We found a significant effect both of treatment, favoring the ACEI (P = 0.04), and of proteinuria level at entry (P = 0.02). No factor, evaluated together by multivariate analysis, significantly explained the probability of remission of proteinuria over the 3-year follow-up. Therefore, by multivariate analysis, we can conclude that treatment with an ACEI significantly slows the rate of progression of renal failure, after accounting for other factors. Moreover, initial proteinuria level was an important predictive factor of progression, independent of both treatments.