COMPARISON OF ANTIHYPERTENSIVE EFFICACY AND SAFETY OF QUINAPRIL AND NITRENDIPINE

In a randomized, double-blind, multicenter parallel study (13 centers) 129 out-patients with mild to moderate essential hypertension were included. After the placebo phase the patients were treated for 24 weeks with the converting enzyme inhibitor quinapril or the calcium channel blocker nitrendipine. The oral daily dosages of quinapril and nitrendipine were 10-40 mg. Both trial drugs had a comparable antihypertensive effect (p < 0.01). The sitting blood pressure was decreased by 14/13 mmHg in the quinapril group and by 15/11 mmHg in the nitrendipine group. The reduction of sitting diastolic blood pressure by quinapril was significantly higher compared to the effect of nitrendipine (p < 0.05). The percentage of responders (patients with a reduction in diastolic blood of at least greater-than-or-equal-to 10 mmHg or to less-than-or-equal-to 90 mmHg( was 70% in the quinapril group versus 63% in the nitrendipine group. Side effects were reported by 13% of the patients treated with quinapril and by 21% of the patients under nitrendipine. There were no metabolic side effects. Routine laboratory results were unchanged at the end of the study. The blood pressure decreasing potency of the converting enzyme inhibitor quinapril and the calcium channel blocker nitrendipine, the safety and the missing metabolic effects were comparable. However, the diastolic blood pressure decrease by quinapril was more pronounced in the sitting position.