The results of a large multicentre study comparing low-dose lisinopril-hydrochlorothiazide with the monocomponents

The efficacy, tolerability and metabolic effects of a fixed combination of lisinopril 10 mg and hydrochlorothiazide 12.5 mg (L/HCTZ) and those of the monocomponents were compared in 286 mild to moderate hypertensive patients in a 17-centre study using a double-blind, randomized, parallel-group design. After 2 weeks of placebo run-in, patients were randomized to one of the three treatments for 8 weeks. Supine and standing BPs were measured at peak blood levels (4-8 hours post dose) after 4 weeks, and at trough blood levels (24-28 hours post dose) after 8 weeks. The BP reduction from baseline was greater with L/HCTZ than with the monocomponents at weeks 4 and 8; at week 8 the reduction was statistically significant vs lisinopril for standing DBP (P less than 0.027) but not for standing SBP; the reduction was significant with L/HCTZ vs hydrochlorothiazide at week 4 [P = 0.0002/0.0001 (SBP/DBP) supine; P = 0.0002/0.0002 standing] and at week 8 (P = 0.0001/0.0001 supine and standing). Response at week 8 (supine DBP less than or equal to 90 mm Hg) with L/HCTZ (87.0%) was greater than with hydrochlorothiazide (29.0%; P less than 0.0001) and marginally greater than with lisinopril (74.2%; P = 0.069). Heart rate fell statistically significantly more with L/HCTZ (by 3.3 beats/minute) than with HCTZ (by 0.86 beats/minute; P = 0.018). L/HCTZ treatment significantly increased plasma uric acid levels compared with lisinopril. L/HCTZ decreased potassium, while lisinopril increased potassium. L/HCTZ decreased cholesterol; HCTZ increased it. Adverse effects were more common on L/HCTZ vs lisinopril (P = 0.033) but not vs hydrochlorothiazide.(ABSTRACT TRUNCATED AT 250 WORDS)