By Nathan Seppa, Science News
CHICAGO—The cardiac benefits of having a daily drink or two might extend to a surprising group—men with heart disease so bad it has required coronary bypass surgery.
The value of light-to-moderate drinking for cardiovascular health has shown up previously in healthy people, with studies showing that—other things being equal—people who regularly drank in moderation had less heart disease and fewer strokes than did nondrinkers.
But moderate drinking's protective benefits may also extend to those who already have some cardiovascular disease, suggests work presented by cardiac surgeon Umberto Benedetto of the University of Rome La Sapienza. Benedetto reported the new findings November 14 at the meeting of the American Heart Association.
He and his colleagues recruited 1,221 people who had disease severe enough to require coronary artery bypass surgery, in which a vessel is taken from another part of the body and grafted onto the heart. The grafted vessel serves as a clean conduit to restore normal blood flow to the heart muscle. In the United States, doctors perform the surgery, which bypasses a hopelessly clogged artery, on more than 300,000 people each year.
The Italian team focused on men, who represented four-fifths of the people in the study. During a post-surgery follow-up period that averaged 3.5 years, about one in six had a heart attack, required more surgery, had a stroke or died. Those who continued to drink alcohol, though not to excess, after surgery were 11 to 39 percent less likely to encounter one of these problems as were teetotalers, the researchers found. The optimal alcohol intake in the men was about two drinks per day, Benedetto says.
There were too few women in the study to do a separate analysis, but generally moderate drinking for women is defined as one daily drink, which adjusts for weight differences.
Only one earlier study had investigated the effect of alcohol consumption in people who had undergone coronary bypass surgery, and that research measured alcohol intake before the operation, not afterward, as the new one did, he says.
"We find that some people stop drinking after surgery, since they believe it might be dangerous," Benedetto says. "Maybe the message of this study is that patients…who drink a little should not be discouraged" from continuing after bypass surgery.
Cardiologist Erin Michos of Johns Hopkins University in Baltimore says she doesn't encourage moderate drinkers to stop. "But for individuals that don't drink, I don't encourage them to start," she says. Michos also notes that the benefits of alcohol on vascular diseases stem from a regular, modest intake, not binge drinking. "Up to two drinks per day can't be weighted over a week as ten in one sitting," she says.
Despite more than 10 years of research on the topic, some doctors are still leery of encouraging any alcohol consumption, whether a patient has heart disease or not, says cardiologist Valentin Fuster of Mt. Sinai School of Medicine in New York, a former president of AHA. "It's important to deal with this with great caution," he says. And although the cardiac benefits of light drinking are well-established, Fuster points out, the mechanism by which alcohol accomplishes this feat is not.