Women treated for high blood pressure with a drug combination that included a calcium channel blocker had a higher risk of death than those given other drug therapies, a study said on Tuesday.

The overall risk of heart-related death was low among the more than 30,000 post-menopausal women included in the six-year study, but the highest mortality rate was among the 1,223 women taking both a calcium channel blocker and a diuretic.

Thirty-one of the 1,223 women on that drug combination died from cardiovascular disease, representing an 85-percent higher risk of death compared to women taking a diuretic and a beta-blocker. Diuretics and beta-blockers are older classes of hypertension drugs.

Also included in the study were women taking ACE inhibitors, a newer class of hypertension drugs, which did not carry an elevated mortality risk when taken in combination with a diuretic.

In many cases, doctors prescribe different classes of blood pressure drugs in combination, one often a diuretic that increases urine flow and flushes the system.

A little more than one third of the women in the study were taking a single drug and their risk of dying from cardiovascular disease was lower than those taking the diuretic-calcium channel blocker combination.

“A woman should go to her doctor and ask, why am I on this particular combination, and is this the best combination for me?” said Sylvia Wassertheil-Smoller of the Albert Einstein College of Medicine, author of the study in this week’s issue of the Journal of the American Medical Association.

She said two drawbacks to the study were that it was observational, not controlled, so the drugs were not assigned randomly; and all the participants were women between 50 and 79 so its conclusions might not apply to younger patients.

Roughly 50 million Americans have high blood pressure, a condition that stresses the cardiovascular system and can lead to heart attacks and strokes.

Last week, another study that examined a calcium channel blocker in combination with an ACE inhibitor was stopped early because the drugs offered patients a much better chance of avoiding heart attack and stroke than older pills. That study was sponsored by drug maker Pfizer Inc.

SOURCE: Journal of the American Medical Association, December 15, 2004.