Similar Antihypertensive Efficacy is Seen with Diltiazem and Nifedipine But diltiazem produces greater reductions in myocardial oxygen consumption and heart rate
In a double-blind trial, 12 women and 28 men with a supine diastolic BP;;:,: 100mm Hg randomly received oral diltiazem 90mg bid (n = 20) or oral nifedipine 20mg (20) bid for 8 weeks, following a 2-week placebo run-in. If after 4 weeks of treatment diastolic BP was ;;:,: 95mm Hg, the dose was administered tid.
Mean supine BP for patients receiving diltiazem fell from 168/111 to 152/1 02mm Hg (p < 0.01 /P < 0.001 vs baseline) after 4 weeks and to 147/96mm Hg (p < 0.001/p < 0.001 vs baseline) after 8 weeks. Corresponding decreases for nifedipine-treated patients were from 161/110 to 142/94mm Hg (p < 0.01/p < 0.001 vs baseline) after 4 weeks and to 142/92 (p < 0.001/p < 0.001) vs baseline) after 8 weeks. There was no significant difference between the groups. Both drugs significantly reduced BP during submaximal exercise. Diltiazem led to a greater decrease of the pressure-rate product when exercising (p < 0.01 vs nifedipine) or at rest in the supine position (p < 0.001 vs nifedipine) after 8 weeks of treatment. Diltiazem significantly reduced heart rate during exercise after 4 and 8 weeks. The difference between the treatment groups was significant (p < O.Q1 ).
11 patients receiving nifedipine and 10 receiving diltiazem reported adverse ettects 1nclud1ng fat1gue (4 vs 3, respectively), palpitations (3 vs 5), headache (3 vs 3), flushing (0 vs 3), leg oedema (1 vs 3) and agitation (1 vs 1 ). All these symptoms disappeared within 2 weeks of starting treatment. One pat1ent receiving diltiazem withdrew because of agitation and 2 patients receiving nifedipine withdrew because of flushing and palpitations. Plasma norepinephrine [noradrenaline] was increased after 8 weeks of diltiazem therapy (p < 0.01 ). Very low density lipoprotein cholesterol and low density lipoprotein cholesterol levels fell (p < 0.05) after 8 weeks of nifedipine and diltiazem treatment, respectively.
'Therapy with the calcium entry blockers diltiazem and nifedipine in slow-release forms resulted in a marked blood pressure reduction at rest and during exercise in our subjects with mild to moderate hypertension. ' Schulte K·L. Meyer·Sabellek WA. Haertenberger A. Thiede H·M. Roecker L. et al. Hypertens1on 8 859·865. Oct 1986
8 INPHARMA" 21 Feb 1987 0156-2703/87 /0221-()()()8/0$01.00/0 © ADIS Press
