A MULTICENTRE STUDY TO COMPARE THE THERAPEUTIC EFFICACY OF SUSTAINED‐RELEASE DILTIAZEM AND ENALAPRIL IN THE TREATMENT OF PATIENTS WITH MILD TO MODERATE HYPERTENSION

Abstract

SUMMARY A 14‐week study was conducted in order to compare the efficacy and tolerability of a twice‐daily sustained‐release diltiazem preparation (120 or 180 mg) and once‐daily enalapril (10 or 20 mg). Patients not achieving an adequate response after 6 weeks on monotherapy were given a combination therapy of twice‐daily diltiazem 120 mg and once‐daily enalapril 10 mg. Of the 147 patients admitted to the study, 70 received diltiazem and 77 received enalapril; 17 patients subsequently received combination therapy. Blood pressure reductions in patients completing 12 weeks of therapy were (sitting values): diltiazem 120 mg, 10.2/15.2 mmHg; diltiazem 180 mg, 19.1/14.7 mmHg; enalapril 10 mg, 25.7/17.5 mmHg; enalapril 20 mg, 19.6/14.0 mmHg; and combination therapy, 24.6/15.1 mmHg. No significant differences in the incidence level of individual symptoms were seen between the two groups: 34 (49%) in the diltiazem, 37 (48%) in the enalapril group; and, between weeks 6 and 12, 9 (53%) patients taking combination therapy. Two patients withdrew from the enalapril group and 8 from the diltiazem group. No unexpected side‐effects were seen during the study and no deaths occurred in any treatment group. Twice‐daily sustained‐release diltiazem 120 or 180 mg was shown to be an effective antihypertensive agent and equal in efficacy and patient acceptability to once‐daily enalapril 10 or 20 mg. Combination therapy effectively lowered blood pressure in patients in whom monotherapy was ineffective.