Study finds risks for beta blockers with surgery

By Julie Steenhuysen

CHICAGO (Reuters) - People given a blood pressure drug known as a beta blocker to reduce heart risks before surgery were one-third more likely to die within a month and had double the risk of stroke compared with those given a dummy pill, Canadian researchers said on Monday.

The study is the largest, most rigorous to date looking at whether beta blockers do more harm than good in reducing surgery-related risks. Other, smaller studies have had mixed results.

"There is a real potential that beta blockers are causing serious harm in the surgical setting," said Dr. P.J. Devereaux of McMaster University in Ontario, whose study appears in the journal Lancet.

"If my mother was undergoing surgery and given a beta blocker, I would be extremely upset based on this evidence."

The findings challenge the long-held belief that giving people a beta blocker before major surgery protects them from heart risks brought on by the stress of the procedure.

Surgery often raises levels of a stress hormone known as catecholamine, which drives up a person's blood pressure and heart rate. "Beta blockers block the effects of increased catecholamines, so the physiological rationale would say they would be beneficial to people," Devereaux said in a telephone interview.

He and colleagues set out to test this idea. They studied more than 8,000 patients in 23 countries at 190 hospitals who were undergoing major surgery unrelated to the heart. People in the study had or were at risk for clogged arteries.

STROKE VS HEART ATTACK