Calcium Channel Blockers Not Best for Hypertension

Calcium channel blockers, popular drugs used to lower high blood pressure, are not as effective as other treatments, researchers said today.

Two reviews of studies assessing blood pressure drugs, published in The Lancet medical journal, showed people treated with calcium channel blockers (CCBs) were more likely to suffer a heart attack or other complications.

“In an analysis of more than 27,000 patients with high blood pressure, we found that those treated with CCBs had a 26 percent higher risk of heart attack and a 25 percent higher risk of heart failure than those treated with other drugs,” said Professor Marco Pahor.

Better Than Nothing

CCBs were more effective than no treatment, but the risk of all heart problems — heart attacks, stroke, heart failure and death from heart disease — was 10 percent higher in patients treated with CCBs.

“These results show that CCBs are less effective than the standard drugs used to treat high blood pressure,” Pahor, of Wake Forest University Baptist Medical Center in North Carolina, added.

CCBs, which are also known as calcium antagonists, work by inhibiting the passage of calcium, an important element for muscle contraction, into cells of the heart and muscle fibers of blood vessels.

The researchers compared the effects of CCBs to diuretics or water pills, and beta-blockers and ACE (angiotension converting enzyme) inhibitors.

The review of nine studies showed CCBs were just as good as the other treatment in lowering blood pressure but not as effective in preventing complications such as heart attacks and heart failure.

Limited Use of CCBs

“These data reinforce the view that use of CCBs should be limited to patients who do not tolerate, or who have failed on diuretics, beta blockers or ACE inhibitors,” said Dr William Applegate, a co-author of the study.

The findings were supported by another overview by researchers in Australia. It showed CCBs decreased the risk of stroke but did not significantly reduce cases of heart disease, heart failure and deaths.

In a commentary in The Lancet, Jiang He and Paul Whelton of Tulane University in New Orleans said the overviews show CCBs should be used selectively.

“The findings indicate the need for caution in recommending calcium antagonists as initial antihypertensive [low-blood pressure] drug therapy in populations at risk of coronary heart disease and heart failure,” they said.

“It might be wise to use calcium antagonists as initial antihypertensive drugs for patients at high risk of stroke and at low risk of coronary heart disease,” they added.