Calcium entry blockade or beta-blockade in long-term management of hypertension in blacks

The long-term efficacy of nitrendipine and acebutolol was assessed during a 40-week double-blind randomized trial in 60 hypertensive blacks. Nitrendipine (mean dose 32 mg/day) and acebutolol (414 mg/day) were administered in monotherapy in increasing dosage and mefruside was added in patients not controlled by monotherapy. The recumbent and standing blood pressures were reduced (P less than 0.01 or less) during monotherapy with nitrendipine and acebutolol, but the magnitude of blood pressure reduction was greater (P less than 0.05 or less) during nitrendipine dosing. Pulse rate decreased (P less than 0.01) during acebutolol whereas nitrendipine induced a nonsignificant increase. Both treatments induced no changes in serum electrolytes, creatinine, urea, uric acid, lipids, plasma renin activity, and plasma and urinary aldosterone. The overall incidence of side effects was similar with both treatments but four patients discontinued nitrendipine because of headache. The addition of mefruside to nitrendipine or acebutolol produced a further fall of blood pressure in patients not controlled with monotherapy. Monotherapy with nitrendipine or acebutolol offers an effective, safe first-line antihypertensive treatment in blacks entered in this study; with the described dosages and therapeutic schedule, nitrendipine was somewhat more effective than acebutolol.