In people with mild cognitive impairment, up to one drink of alcohol a day may slow their progression to dementia, according to a study published in the May 22, 2007, issue of Neurology®. Mild cognitive impairment is a transitional stage between normal aging and dementia that is used to classify people with mild memory or cognitive problems and no significant disability.

Researchers evaluated alcohol consumption and the incidence of mild cognitive impairment in 1,445 people. They then followed 121 people with mild cognitive impairment and their progression to dementia. The participants, age 65 to 84, were part of the Italian Longitudinal Study on Aging and were followed for three-and-a-half years.

The study found people with mild cognitive impairment who had up to one drink of alcohol a day, mostly wine, developed dementia at an 85 percent slower rate than people with mild cognitive impairment who never drank alcohol.

"While many studies have assessed alcohol consumption and cognitive function in the elderly, this is the first study to look at how alcohol consumption affects the rate of progression of mild cognitive impairment to dementia," said study authors Vincenzo Solfrizzi, MD, PhD, and Francesco Panza, MD, PhD, with the Department of Geriatrics at the University of Bari, in Bari, Italy. "The mechanism responsible for why low alcohol consumption appears to protect against the progression to dementia isn't known. However, it is possible that the arrangement of blood vessels in the brain may play a role in why alcohol consumption appears to protect against dementia. This would support other observations that drinking moderate amounts of alcohol may protect the brain from stroke and vascular dementia."

The study did not find any association between higher levels of drinking, more than one drink per day, and the rate of progression to dementia in people with mild cognitive impairment compared to non-drinkers.