PARALLEL COMPARATIVE TRIAL OF AMLODIPINE AND NITRENDIPINE MONOTHERAPYIN PATIENTS WITH ESSENTIAL-HYPERTENSION

Objectives To compare the blood pressure effects of two dihydropyridin e calcium channel blockers, amlodipine and nitrendipine, in 488 patien ts with essential hypertension. Methods The study used a randomized, s ingle-blind design of 4 weeks' duration conducted at four medical cent res in China Patients were randomized to receive either amlodipine mon otherapy (5-10 mg once daily; n = 334) or nitrendipine (10 mg twice or three times daily; n = 154). Blood pressure was evaluated by standard blood pressure measurements before and after treatment, and by 24 h a mbulatory blood pressure monitoring in a subgroup of patients (n = 18) . Results Both systolic and diastolic blood pressures were reduced fro m baseline after 4 weeks of amlodipine and nitrendipine monotherapy. D iastolic blood pressure was reduced by 14.4% in the amlodipine group, which was significantly better than the 13.0% reduction in the nitrend ipine group (P< 0.05), In addition, blood pressure response rates were significantly better with amlodipine monotherapy than with nitrendipi ne monotherapy. In the subgroup of patients undergoing 24 h ambulatory blood pressure monitoring, both systolic and diastolic blood pressure were reduced from baseline in the amlodipine and nitrendipine groups. Adverse effects were generally mild, with dizziness, flushing, palpit ation, headache, drowsiness and ankle oedema being the most common. Fl ushing and headache were more frequent in the nitrendipine group than in the amlodipine group (P< 0.05 for flushing and P<0.01 for headache) . Conclusions Amlodipine monotherapy reduced blood pressure more effec tively than nitrendipine monotherapy in patients with essential hypert ension and was associated with fewer adverse events. J Hypertens 16 (s uppl 4):S43-S47 (C) 1998 Lippincott Williams & Wilkins