Comparative study of angiotensin converting enzyme inhibitor and calcium channel blocker in the treatment of steroid-resistant idiopathic nephrotic syndrome.

ABSTRACT

BACKGROUND: The aim of this study was to evaluate and compare the anti-proteinuric effect of ramipril and verapamil in patients with steroid-resistant idiopathic nephrotic syndrome. Twenty one (21) cases of steroid-resistant idiopathic nephrotic syndrome were randomized to receive ramipril (11) and verapamil (10) and were followed up for 12 months; monthly for the 1st 3 months and then every 3 months for the remaining study period. The degree of reduction of proteinuria, blood pressure, serum creatinine, serum albumin and side effects were noted between the two groups. The comparison within the groups over different time periods was made using paired 't' test and between the groups for specific time period by unpaired 't' test. The level of significance was taken as 5% or below. RESULTS: Seventeen patients (nine in the ramipril group and eight in the verapamil group) completed the study. The mean age of the patients, duration of illness, 24 hours urinary excretion of protein, mean arterial pressure, serum creatinine, cholesterol and albumin were similar in both the groups at time of randomization. The 24 hours urinary protein excretion decreased from 6319.44 +/- 1971.70 mg/day to 1852.44 +/- 1813.74 mg/day in patients receiving ramipril and from 5332.87 +/- 1947.47 mg /day to 2759.37 +/- 1929.6 mg/day in patients treated with verapamil after 12 months. There was no statistically significant difference in the reduction of proteinuria between the two groups. However, reduction in proteinuria was statistically significant from 2nd month onwards in Ramipril group and reduction was sustained throughout the study period. Reduction in mean arterial pressure was better achieved in Ramipril groups. The change in the serum potassium, creatinine, cholesterol and albumin were similar in either group of patients. Cough (2), hypotension (1) and reversible rise in serum creatinine (1) were observed with ramipril and no side effect was noted with verapamil. CONCLUSION: Both ramipril and verapamil can reduce proteinuria in patients suffering from steroid-resistant idiopathic nephrotic syndrome. However, ramipril had a better and sustained reduction in proteinuria with well-controlled mean arterial pressure. Verapamil can be considered as an alternative to ramipril when the use of the latter is not tolerated because of side effects and/or worsening of renal function in patients with chronic renal insufficiency.