Long-term therapy with slow-release nifedipine in essential hypertension

Summary

The purpose of this study, designed as an open multicenter trial, was to test the antihypertensive efficacy, patient acceptability, and side effects of long-term treatment with slow-release nifedipine in alarge population. The drug was studied in 330 outpatients with essential hypertension, WHO stage 1–2, recruited in 20 hospital centers. After washout period was completed, nifedipine (20 mg bid) was given for 1 month (phase 1). Then, the treatment was extended for 4 months (phase 2) with variable doses (rang 20–80 mg daily). No other antihypertensive drugs were administered during phase 1. However diuretics, beta blockers, or captorpril were added to nifedipine during phase 2 in 11 patients. Seventy patients did not meet ciiteria for inclusion at washout. During phase 1 and 2, 66 additional patients were excluded due to side effects, the need of other antihyperftnsive drugs, or noncomplicance. Systolic blood pressure significantly lowered (10% or more) in 84% patients in phase 1 and in 76% in phase 2. No responders were 6.1% and 3.6%, respectively. Diastolic blood pressure was normalized in 60% of patients after 5 months of therapy. Effects on blood pressure were equal in young patients and in the elderly, but a minimal rise in heart rate was recroded in younger patients.

At least one side effect occurred in 46.6% patients, mainly headeche (15.4%), hot flashes (13.3%), ankle edema (12.8%), or palpitation (6.6%). Sixteen patients (8.2%) were obliged to stop nifedipine treatment due to the severity of the side effects. This trial confirms the efficacy of nifedipine in hypertension, both in young and in aged patients. The adherence of patients to the twice-daily regimen was very good, without the development of tolerance in long-term treatment. The drug does not affect the physiologic cardiovacscuolar response to standing, but induces several relatively common, very seldom severe, adverse reactions.