Cocaine use boosts heart-attack risk.

Bearing out researchers' longstanding suspicion of a link between cocaine use and heart attacks, a new study confirms that cocaine users' risk skyrockets within minutes of taking the drug.

Cocaine is "one of the strongest triggers of heart attacks," concludes Murray A. Mittleman of Beth Israel Deaconess Medical Center in Boston. "The only thing that comes close is the case of the completely sedentary person who suddenly goes out and does vigorous exercise."

Mittleman and his coworkers analyzed records of 3,946 patients who had had heart attacks. Of those, 38 said they had used cocaine in the year before being stricken, and 9 reported taking cocaine an hour or less before heart-attack symptoms appeared. The researchers estimate that during that hour, these otherwise low-risk individuals had an abrupt increase in heart-attack risk to 24 times the normal risk.

"It's what everybody suspected for a long time, and they did a nice job of actually proving it," says Judd E. Hollander of the University of Pennsylvania in Philadelphia. "Putting a number on it ... shows just how dangerous the drug is. It's a lifelong Russian roulette."

The likelihood of heart attack returned to normal just 2 to 3 hours after cocaine use, Mittleman's team reports in the June CIRCULATION.

Cocaine users were, on average, 17 years younger than nonusers when their heart attacks occurred and were more likely than nonusers to be male, nonwhite, and current smokers. The researchers accounted for these other risk factors when they calculated cocaine's threat.

"There are about 5 million regular users of cocaine in the U.S. and about 30 million people who have experimented with the drug," Mittleman says. "If this information could be disseminated, it could help put the effects of cocaine, particularly on younger people, into context."