Treating mild-to-moderate hypertension: a comparison of lisinopril-hydrochlorothiazide fixed combination with captopril and hydrochlorothiazide free combination.
The fixed combination comprising lisinopril 10 mg and hydrochlorothiazide 12.5 mg once daily (L/HCTZ) was compared with captopril 25 mg and hydrochlorothiazide 25 mg once daily (C/HCTZ) in a randomized, double-blind, parallel-group study. After a 2-4 week placebo run-in period patients were randomized to L/HCTZ (n = 82) or C/HCTZ (n = 83) for 8 weeks. After 8 weeks, peak blood levels of both treatments showed lowered sitting BPs (-22.8/-14.3 mm Hg for L/HCTZ vs -22.8/-14.0 mm Hg for C/HCTZ), and standing BPs (-22.6/-13.1 mm Hg vs -21.6/-12.8 mm Hg, respectively). Between-drug differences were not significant (ns). At trough blood levels L/HCTZ lowered sitting BPs more than C/HCTZ, -23.6/-14.9 mm Hg vs -16.0/-11.3 mm Hg (P less than 0.02/less than 0.03), respectively. The effect on standing BP was similar, -22.0/-13.8 mm Hg vs -15.1/-10.3 mm Hg (P less than 0.03/less than 0.05) for L/HCTZ and C/HCTZ, respectively. Both treatments slightly increased heart rate (ns). Serum potassium fell more with C/HCTZ than with L/HCTZ (P less than 0.005). The fasting glucose level rose with L/HCTZ and fell with C/HCTZ. Uric acid, triglycerides and fasting cholesterol levels rose in both groups (ns). There were no differences between treatments with respect to adverse events. L/HCTZ appears to be a well-tolerated combination with efficacy on once-daily dosing superior to that of C/HCTZ.