Efficacy of once daily nitrendipine in mild hypertension: comparison with placebo.

A randomized, double-blind, parallel group study was carried out to compare the antihypertensive efficacy of nitrendipine with that of placebo in 80 mild hypertensives. The dose of nitrendipine was initially 10 mg once daily and was doubled to 20 mg once daily after four weeks in patients who responded poorly (33% of patients on nitrendipine and 49% of patients on placebo required doubling of dose). Blood pressure was assessed 20 to 24 h after dosing. Mean (+/- standard error) reductions in supine systolic and diastolic blood pressures for patients who completed 10 weeks of therapy were significantly greater for the nitrendipine group than for the placebo group (systolic blood pressure 18.1 +/- 2.7 mmHg versus 4.2 +/- 2.5, P less than 0.0001; and diastolic blood pressure 10.6 +/- 1.1 mmHg versus 6.6 +/- 1.3, P = 0.002). A comparison of mean reductions in standing systolic and diastolic blood pressures produced similar results. Goal of therapy (diastolic blood pressure no more than 90 mmHg or reduction of at least 10 mmHg) was achieved in 71% of nitrendipine-treated and 45% of placebo-treated patients (P less than 0.05). Nine of 80 patients randomized to therapy dropped out during treatment (nitrendipine: four adverse experiences and one moved from the area; placebo: two adverse experiences, and drug ineffective in two). Overall, the incidence of adverse experiences considered by the physician to be related to treatment was higher in the placebo group (32%) than in the nitrendipine group (23%). Only flushing had a higher incidence in the nitrendipine group; however, the overall incidence was low (9%).(ABSTRACT TRUNCATED AT 250 WORDS)