EFFICACY AND TOLERANCE OF SUSTAINED-RELEASE DILTIAZEM-300MG AND A DIURETIC IN THE ELDERLY

A randomized, double-blind, parallel study has been performed to compare the antihypertensive action and clinical and biological tolerance of monotherapy with two different substances: substained-release diltiazem 300 mg and a diuretic combining 25 mg of hydrochlorothiazide and 50 mg of triamterene (HCT-T). Antihypertensive treatment was suspended at least 15 days before initiation of a placebo period that lasted 14 days and allowed confirmation of persisting hypertension. Eighty-five patients who were at least 65 years old were included in the study: 42 in the group treated with sustained-release diltiazem 300 mg and 43 in the group treated with a diuretic. All of them presented with mild to moderate arterial hypertension, characterized by supine diastolic blood pressures (supine DBP) of 95-115 mm Hg. Duration of treatment was 3 months. After 1 and 3 months, efficacy and tolerance of the antihypertensive treatment were evaluated. On day 30, a significant decrease (p < 0.0001) in the main parameter, i.e., supine DBP, as well as other parameters such as standing diastolic blood pressure (standing DBP), supine systolic blood pressure (supine SBP), and standing systolic blood pressure (standing SBP) was observed. Blood pressure was reduced by 18, 16, 28, and 26 mm Hg, respectively, in the sustained-release diltiazem 300 mg group and by 13, 12, 21, and 18 mm Hg, respectively, in the diuretic group. Moreover, on day 90, blood pressure values were maintained in the diuretic-treated group, whereas an additional significant reduction in supine DBP (p < 0.002) was noted in the sustained-release diltiazem 300 mg-treated group (-4.8 mm Hg). Cardiac and electrocardiographic tolerance were good in both groups. Side effects were more severe in the diuretic-treated group. In elderly, moderately hypertensive patients, administration of sustained-release diltiazem 300 mg is more effective and better tolerated than monotherapy with 25 mg of hydrochlorothiazide in conjunction with 50 mg of triamterene.