Effect of two antihypertensive combinations on metabolic control in type-2 diabetic hypertensive patients with albuminuria: A randomised, double-blind study

Abstract

The objective of this study was to compare, at equal blood pressure (BP) reduction, the effect of two different combinations on metabolic control and albuminuria in type 2 diabetic hypertensive patients with albuminuria. This was a prospective, randomised, double-blind, parallel, controlled trial carried out in 11 Spanish hospitals. A total of 103 type 2 diabetic patients with stable albuminuria and BP not controlled on monotherapy were randomised of which 93 finished the study. After a 4-week single-blind placebo period, patients were randomised to verapamil SR/trandolapril 180/2 mg (VT) or to enalapril/hydroclorothiazide 20/12.5 mg (EH). Treatment duration was 6 months. The main outcome measures were changes in BP, 24-h albuminuria, blood glucose and glycated haemoglobin. Overall BP was significantly reduced from 157.3 ± 12.0/98.3 ± 6.4 mm Hg to 140.5 ± 14.5/86.1 ± 8.2 mm Hg (P < 0.001) and albuminuria significantly decreased from 508.6 ± 693.8 mg/24 h to 253.4 ± 517.2 mg/24 h (P < 0.001), both without significant differences between treatments. Glycated haemoglobin was not modified on VT: baseline, 5.91 ± 1.43%; end of treatment, 5.94 ± 1.62%, but increased on EH: baseline, 5.96 ± 1.25%; final, 6.41 ± 1.51%, (ANOVA interaction P = 0.040). At the end of the study, a blood glucose <126 mg/dL was attained in 72.7% of the VT group—improving in 29.5% and worsening in 6.8% of patients (P = 0.021)—and in 50% of the EH group, 13.6% of patients improved and 11.4% worsened (P = 1.000). There were no changes in body weight, serum creatinine, uric acid, potassium, cholesterol, tryglicerides and serum albumin. In hypertensive type 2 diabetic patients not controlled on monotherapy, both treatments similarly reduced albuminuria. The combination verapamil/ trandolapril seems to allow a better metabolic control than enalapril/hydroclorothiazide.