Some blood pressure drugs may raise risk of heart attack

Calcium-channel blockers, widely prescribed to lower high blood pressure, may actually increase the risk of heart attack by as much as 60 percent, UW researchers reported March 10.

Of those Americans taking blood pressure medicine, about 20 to 25 percent are taking calcium-channel blockers such as Adalat, Calan, Cardizem, Dilacor, Isoptin and Verelan. Many scientists believe that calcium-channel blockers inhibit the movement of calcium ions across cell membranes in the heart and blood vessels, relaxing vascular muscle and dilating arteries.

But doctors are rethinking the medication after the UW study. Comparing patients taking calcium-channel blockers to a similar group that didn’t, researchers found that the risk of a heart attack increased by as much as 60 percent.

“This study suggests that, compared with other therapies, calcium-channel blockers, especially in high dosages, may increase the risk of myocardial infarction,” stated the group of researchers, led by UW Medicine Profes­sor Bruce Psaty. National guidelines recommend the use of diuretics and beta-blockers as the “first-line” defense against high blood pressure.