Do Some Blood Pressure Drugs Up Heart Risk?
Study: Calcium Channel Blockers May Not Work as Well in Women as Other Drugs
Dec. 14, 2004 -- One common type of blood pressure drug may not work as well as others at preventing heart death, a new study shows.
The data comes from women aged 50-79 enrolled in the Women's Health Initiative (WHI). It's the same study that showed hormone replacement therapy to be less effective and more risky than previously thought. Now the study shows a higher risk of heart death in women who take blood pressure drugs known as calcium channel blockers.
Calcium channel blockers include, but are not limited to, drugs sold under the brand names Norvasc, Plendil, DynaCirc, Cardene, Procardia XL, Adalat, Cardizem, Dilacor, Tiazac, Diltia XL, Isoptin, Calan, Verelan, and Covera-HS.
Researcher Sylvia Wassertheil-Smoller, PhD, heads the epidemiology division at Albert Einstein College of Medicine, in Bronx, N.Y. The findings appear in the Dec. 15 issue of The Journal of the American Medical Association.
"We found that [high-blood-pressure] therapy combinations that contain the calcium channel blockers were associated with a higher risk of death from heart disease than were other combinations," Wassertheil-Smoller tells WebMD. "Doctors should be cautious with prescribing any drugs, but particularly with this one. Doctors may have a very good reason for giving a patient a calcium channel blocker, but it should not blindly be given."
Don't Stop Taking Blood Pressure Drugs
Should people stop taking these drugs? No, Wassertheil-Smoller says. Why not? It's dangerous to stop taking any prescribed medicine -- blood pressure drugs in particular -- before seeing one's doctor.
Current treatment guidelines say that all approved blood pressure drugs are safe and effective. The new findings do not change those recommendations, says American Heart Association spokesman Daniel Jones, MD, dean of the University of Mississippi School of Medicine.
"The bulk of clinical trials show calcium channel blockers are safe and effective at lowering blood pressure," Jones tells WebMD. "Our current guidelines focus on lowering blood pressure and not much on what class of drugs you use to do that. This study, while intriguing, doesn't do anything to change that."
Twofold Higher Death Risk
The study looked at more than 30,000 women with high blood pressure but no history of heart disease. Some of the women took only one kind of blood pressure drug:
A diuretic or water pill. The most common water pill is hydrochlorothiazide
A beta-blocker. Common brand names include Inderal, Tenormin, Lopressor, and Toprol-XL.
An ACE inhibitor. Common brand names include Capoten, Vasotec, Prinivil, Zestril, Lotensin, Monopril, Altace, and Accupril.
A calcium channel blocker. This includes drugs such as Norvasc, Cardizem, Calan, and Adalat.
Some of the women took combinations of these drugs.
A recent clinical trial showed that diuretics are the best blood pressure drugs to try first. Among women in the WHI, there was no significant difference in heart deaths between women who took diuretics alone and women who took either beta-blockers or ACE inhibitors. But those who took calcium channel blockers alone had a 55% higher risk of dying from heart disease.