Moderate drinking may stave off dementia

NEW YORK (Reuters Health) - Having one or two alcoholic drinks per day may help prevent dementia in the elderly, according to study findings presented Monday at the Alzheimer's Association 2009 International Conference on Alzheimer's Disease in Vienna, Austria. Too much alcohol use, however, may promote dementia.

The results indicate that cognitively normal adults, 75 years or older, who are moderate drinkers are 40 percent less likely to develop dementia over 6 years than are their non-drinking peers. By contrast, alcohol use appears to offer no benefit, and possibly harm, for adults who already have some degree of cognitive impairment.

"We were pleased to see that the beneficial effects of moderate alcohol intake reported in middle-aged adults also extend to cognitively normal older adults over 75," lead author Dr. Kaycee M. Sink, from Wake Forest University School of Medicine in Winston-Salem, North Carolina, told Reuters Health.

Dr. Sink noted that her team's study is not the first to look at the association between alcohol use and the risk of dementia, but said that several factors make it unique.

"It is one of largest, longest studies of older adults living in the US to examine this question; the participants are older than most previously studied; and we were able to look at the effects of alcohol consumption in both cognitively normal older adults as well as those who had mild cognitive impairment."

The subjects included 3069 adults who were enrolled in the Ginkgo Evaluation of Memory Study (GEMS). Based on extensive testing, the subjects were classified as having normal cognition or mild impairment at baseline. Alcohol use was categorized as none, light, moderate, or heavy, based on having 0, 1 to 7, 8 to 14, or >14 drinks per week, respectively.

At the start of the study, 2587 subjects had normal cognition and 482 had mild cognitive impairment. In terms of alcohol use, about 40 percent were either none or light drinkers, and about 10 percent each were moderate or heavy users.

More than 500 cases of dementia developed in the entire group over the period of the study. As noted, among those who were cognitively normal at the start of the study, moderate alcohol drinkers appeared to be protected against dementia.

In subjects with mild cognitive impairment, however, heavy alcohol users half nearly doubled the risk of dementia relative to non-use, Dr. Sink said.

"Since every individual has different medical conditions and family history, alcohol consumption may not be appropriate for everyone wanting to limit their risk of developing dementia," Dr. Sink noted. "What we can say, based on this study, is that our results support current guideline recommendations for alcohol intake into old age and do not necessarily support the need for people with normal cognition who drink moderately to change their drinking habits."