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Wednesday, March 19, 2003

By Anita Srikameswaran, Post-Gazette Staff Writer

New research indicates that seniors who have one to six alcoholic drinks a week have a lower risk of dementia than either teetotalers or heavy tipplers.

But don't raise a glass in celebration just yet.

One of the authors of the study cautions that the alcohol intake may not be protective, but just reflect the fact that people who don't have dementia do have an active social life in which they are more likely to drink.

The study, published today in the Journal of the American Medical Association, compared alcohol consumption patterns of 373 patients with dementia with an equal number of people who did not have dementia, all pulled from a larger, long-term study on heart health among people 65 and older in Allegheny County and in Maryland, North Carolina and California.

"We found that abstainers had odds of dementia that were about twice as high as the odds of moderate drinkers," said the lead author, Dr. Kenneth Mukamal, an assistant professor of medicine at Harvard University. "Furthermore, those who drank 14 or more drinks a week also had a higher risk of dementia than moderate drinkers."

Moderate drinkers had a 54 percent lower risk of dementia than abstainers, while heavier drinkers had a 22 percent higher risk. Heavier drinking was particularly linked to dementia among men, for whom the odds were doubled.

The association between moderate alcohol consumption and reduced dementia risk held up even after taking into account other factors, such as weight, tobacco use, physical activity and genetic predisposition to dementia.

But Dr. Lewis Kuller, a member of the research team and an epidemiologist at the University of Pittsburgh Graduate School of Public Health, called Mukamal's interpretation the viewpoint of an optimist.

"If you're an optimist, you say that alcohol has some effect in preventing the development of dementia," he said. Alcohol could affect the brain's blood vessels, the formation and deposition of the plaques characteristic of Alzheimer disease, or the brain's nerve cells themselves.

But other explanations are plausible, Kuller said, particularly when close attention is paid to the women in the study. Unlike the men, female study participants had a lower likelihood of having dementia even if they had seven or more drinks per week.

Women are more likely to imbibe in social settings, Kuller noted. Other research he has conducted indicates that as patients begin developing the earliest signs of dementia, they become less social, tending to avoid others even as others start avoiding them.

So a bridge player may have a glass of wine after the game. But as mental function begins to decline, often without the patient realizing it, the player may begin to forget the cards. She may not be invited back for another game -- and that means she doesn't drink a glass of wine.

"The argument may be raised that [alcohol consumption] is a marker of socialization or functioning in the community," Kuller explained. As dementia develops, partying and drinking decrease.

Kuller said that a clinical trial could better show what relationship exists between alcohol consumption and dementia, but it is very unlikely that such a study could be undertaken. For one thing, participants would have to be willing to be randomly assigned to abstain or to drink a certain amount of alcohol.