ALLHAT Study Findings Are ‘Color Blind’

Analysis confirms diuretics work better for high blood pressure for both black and non-black patients

Study results suggest that older, cheaper diuretics remain the drug of choice for both black and non-black patients in treating high blood pressure and reducing risk of heart disease. The results were reported by three University of Texas School of Public Health at Houston faculty members in the April 6 issue of The Journal of the American Medical Association.

Barry R. Davis, M.D., Ph.D.

The analysis by race of the "Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial" (ALLHAT), confirms earlier findings that diuretics - rather than newer more expensive drugs such as ACE inhibitors, calcium channel blockers or beta blockers - should be preferred as a first therapy for most patients.

The multi-center ALLHAT study is conducted under a National Institutes of Health contract with The University of Texas Health Science Center at Houston. Barry R. Davis, M.D., Ph.D., professor of biostatistics in the School of Public Health is the principal investigator and a co-author of the JAMA article.

"There was a question whether the diuretics' success with hypertension applied by race because black patients have less success than non-black patients with the ACE inhibitors," said Davis, who also is director of the Coordinating Center for Clinical Trials at the School of Public Health. "However the results showed diuretics were as good as or better than the newer drugs regardless of race."

The study concludes that diuretics are similar to or superior to newer drugs in lowering blood pressure, in tolerability and in preventing the major complications from high blood pressure. Across both racial subgroups, there was substantially higher risk of heart failure - 37 percent - among participants taking calcium channel blockers compared with those on diuretics. When compared to ACE inhibitors, diuretics were more effective in preventing cardiovascular disease, especially heart failure, for all participants and significantly more effective in reducing high blood pressure and preventing stroke in blacks.

"This analysis confirms and extends to all races ALLHAT's original conclusion that diuretics are the right first-line therapy for high blood pressure. While some other recent studies have evaluated newer therapies (including drug combinations), the weight of evidence, particularly in this multi-racial study, supports the diuretic recommendation," said Jeffrey Cutler, M.D., National Heart, Lung and Blood Institute senior analyst and a study co-author.

J. Kay Dunn, Ph.D., and Charles E. Ford, Ph.D., both associate professors of biostatistics at the School of Public Health, also are co-authors of the JAMA article.

Initial findings of the ALLHAT study were published in JAMA in December 2002. ALLHAT was the largest clinical trial of hypertension treatment ever conducted, involving 42,218 participants aged 55 and older. Thirty-five percent of the participants were black.

High blood pressure affects about 65 million Americans, or one in four adults, and its prevalence increases with age - more than half of those over age 60 have hypertension. High blood pressure is a risk factor for heart disease and the chief risk factor for heart failure and stroke.

By Melanie Hillis, Public Affairs