Combo drugs best for lowering blood pressure

By David Douglas

NEW YORK (Reuters Health) - A low-dose four-drug combination appears to be more effective for reducing high blood pressure, or hypertension, than treatment with a high dose of a single drug, according to Irish investigators.

"Most people with high blood pressure need two to three separate antihypertensive drugs," Dr. John Feely told Reuters Health. "Combining low doses of established antihypertensive medicines in a single preparation or capsule can produce better blood pressure control than full doses of individual drugs."

Feely and Dr. Azra Mahmud of Trinity College, Dublin, investigated this approach by studying 108 untreated, white, hypertensive patients, and report the results in the medical journal Hypertension.

The subjects were randomly allocated to take one of four agents -- a calcium channel blocker, a beta-blocker, a diuretic, or an ACE inhibitor -- or a capsule containing all four drugs at one quarter of the dose used for single-drug therapy.

After 4 weeks, the reduction in pressure with the combination treatment was 19 points, significantly greater than the 6 to 11 points seen with the various individual agents.

Moreover, 60 percent of combination-drug patients achieved a normal blood pressure reading compared with 15 percent to 45 percent of patients taking individual drugs.

The combination approach, Dr. Feely concluded, "has the potential to reduce costs, with possibly fewer side effects, and the number of medicines to be taken each day."

In an accompanying editorial, Dr. John L. Reid, of the University of Glasgow, agrees, pointing out in remarks to Reuters Health that the study "provides new insights into potential approaches using very low doses of available drugs."

However, he added, "there is still a lot of work to be done in optimizing the drugs and doses and in confirming long-term benefit over months and years."

SOURCE: Hypertension, January 2007.