Comparative effects of diltiazem sustained-release and captopril on blood pressure control and plasma lipoproteins in primary hypertension: a randomized, double-blind, crossover study.

We compared the effects of sustained-release diltiazem and captopril on blood pressure control and lipid profile. Forty-eight patients with primary hypertension were included in this randomized, double-blind, crossover study and 43 completed the trial. Following a two-to four-week placebo run-in period, each patient initially received either diltiazem (60-180 mg twice daily) or captopril (25-75 mg twice daily) for 16 weeks and then crossed over to the other drug after an interim placebo washout period. Both drugs significantly reduced systolic (SBP) and diastolic (DPB) blood pressure compared to baseline. However, supine (P less than 0.01), sitting and standing (P less than 0.05) DPB was lower with diltiazem than with captopril. Moreover, BP control (sitting DBP less than 90 mmHg) was achieved in a greater proportion of patients treated with diltiazem (63 vs 44%). Heart rate was significantly reduced (P less than 0.001) with diltiazem in all positions but was unchanged with captopril. Lipid, lipoprotein and apolipoprotein concentrations were not modified with either treatment. We conclude that both diltiazem and captopril are effective antihypertensive agents without deleterious effects on lipid metabolism. However diltiazem provides a better prolonged control of BP and may offer some advantages for patients in whom a slower heart rate would be beneficial.