Regression of microalbuminuria: results of a controlled study, indapamide versus captopril

Our aim was to assess the effect of blood pressure treatment on albumin excretion rate (AER) in diabetic patients using two antihypertensive agents with different modes of action: indapamide and captopril. Patients with persistent microalbuminuria on two occasions (AER 20-200 micrograms/min) entered a randomized crossover study of 12 weeks of therapy with a constant dose of either indapamide 2.5 mg daily or captopril 12.5 mg three times daily, with a 4-week washout between therapy periods. Blood pressure was measured using a random-zero sphygmomanometer and AER by radioimmunoassay on a timed urine collection. Results (mean +/- standard deviation) were analyzed by repeated measures of analysis of variance after log transformation of AER data. Twelve patients [nine men; mean age 58 +/- 7.5 years (range 49-73 years), all with non-insulin-dependent diabetes mellitus (NIDDM)] were studied. Both blood pressure [initial mean systolic 144 +/- 14 mm Hg (range 124-166)/initial mean diastolic 85 +/- 6 mm Hg (range 75-96)] and AER [initial 92 +/- 36 micrograms/min (range 36-161)] were significantly reduced below basal levels (at the 0.05 level) at all study intervals by both antihypertensive agents. The results show the importance of blood pressure and its treatment on AER in patients with NIDDM. In this study, indapamide was as effective as an angiotensin-converting enzyme inhibitor in reducing both blood pressure and microalbuminuria.