Single-Drug Therapy for Hypertension in Men -- A Comparison of Six Antihypertensive Agents with Placebo

Abstract

Background: Characteristics such as age and race are often cited as determinants of the response of blood pressure to specific antihypertensive agents, but this clinically important issue has not been examined in sufficiently large trials, involving all standard treatments, to determine the effect of such factors. Methods: In a randomized, double-blind study at 15 clinics, we assigned 1292 men with diastolic blood pressures of 95 to 109 mm Hg, after a placebo washout period, to receive placebo or one of six drugs: hydrochlorothiazide (12.5 to 50 mg per day), atenolol (25 to 100 mg per day), captopril (25 to 100 mg per day), clonidine (0.2 to 0.6 mg per day), a sustained-release preparation of diltiazem (120 to 360 mg per day), or prazosin (4 to 20 mg per day). The drug doses were titrated to a goal of less than 90 mm Hg for maximal diastolic pressure, and the patients continued to receive therapy for at least one year. Results: The mean (±SD) age of the randomized patients was 59 ±10 years, and 48 percent were black. The average blood pressure at base line was 152 ±14/99 ±3 mm Hg. Diltiazem therapy had the highest rate of success: 59 percent of the treated patients had reached the blood-pressure goal at the end of the titration phase and had a diastolic blood pressure of less than 95 mm Hg at one year. Atenolol was successful by this definition in 51 percent of the patients, clonidine in 50 percent, hydrochlorothiazide in 46 percent, captopril in 42 percent, and prazosin in 42 percent; all these agents were superior to placebo (success rate, 25 percent). Diltiazem ranked first for younger blacks (<60 years) and older blacks ( ≥ 60 years), among whom the success rate was 64 percent, captopril for younger whites (success rate, 55 percent), and atenolol for older whites (68 percent). Drug intolerance was more frequent with clonidine (14 percent) and prazosin (12 percent) than with the other drugs. Conclusions: Among men, race and age have an important effect on the response to single-drug therapy for hypertension. In addition to cost and quality of life, these factors should be considered in the initial choice of a drug., The initial treatment for hypertension has changed as drugs with pharmacologic properties permitting single-drug therapy have become available. In their 1988 report, the Joint National Committee on Detection, Evaluation, and Treatment of High Blood Pressure1 considered the selection of initial treatment on the basis of demographic characteristics. Previous cooperative studies by the Department of Veterans Affairs have supported the recommendations of the Joint National Committee, such as proposing that beta-blockers be considered equal to thiazide diuretics in the initial antihypertensive therapy of white patients2,3 and recommending the use of captopril as initial single-drug therapy4,5. We and others… © 1993, Massachusetts Medical Society. All rights reserved.