Long-acting Diltiazem in Monotherapy of Essential Hypertension - a Randomised, Double Blind Study

Abstract

Background The aim of the study was to assess efficacy and tolerability of diltiazem-controlled release tablets in patients with mild-to-moderate essential hypertension.
Methods 70 patients (31 F, 39 M) of age 32-76 (mean 52,3) with diastolic blood pressure measurements between 95 and 110 mm Hg, after 2 weeks run-in placebo phase, were randomized in double blind manner into two groups, each consisting of 35 patients. All patients in those groups received diltiazem in form of controlled release tablets (Oxycardil manufactured by Schwarz Pharma) in doses of either 120 or 240 mg per day The medication was administered once daily (between 7.30 a.m. and 930 a.m.) for 6 weeks. Blood pressure examinations were performed with standarized sphygmomanometers, in sitting position, on right arm, every two weeks. An average of three consecutive measurements, taken 2-3 minutes apart, after at least 15 minutes rest, was used for statistical analysis.
Results Significant decreases of both diastolic (DBP) and systolic blood pressure (SBP) were observed in each group, in comparison with placebo baseline, during the six weeks active treatment phase. After six weeks treatment with 120 mg per day SBP decreased by 14.0 ± 14.3 mmHg and DBP by 10.9 ± 7.6 mmHg. In the group receiving 240 mg/day SBP went down by 15,6 ± 16,1 mmHg and DBP by 9,9 ± 7,9 mmHg. Blood pressure below 140/90 mmHg (SBP/DBP respectively) was achieved in 30% of patients in group treated with 120 mg per day and in 26% of patients from group receiving 240 mg per day Side effects like headache, heart palpitation, bradycardia, dizziness and weakness occurred in 8 patients of whom 7 belonged to group with 240 mg dose. All side effects were mild or moderate and disappeared after a few days of treatment.
Conclusions Investigational drug proved to be a very effective and well tolerated antihypertensive agent. It decreased significantly both systolic and diastolic blood pressure. Hypotensive effect was similar for both doses after 6 weeks while side effects were more frequent in the higher dose group.