A new study, conducted by scientists from the Department of Geriatrics at the University of Bari, in Bari, Italy, found that a drink or two per day may help slow the development of dementia. The research, published in the May 22 issue of the journal Neurology, may provide hope for those at risk of dementia and diagnosed with mild cognitive impairment (MCI), the transitional stage between normal brain function and full-blown, irreversible cognitive impairments, such as Alzheimer's.
Dementia is a medical term used to describe one's progressive rate of cognitive decline. It is usually first recorded as forgetfulness, diagnosed as MCI, and then continues irreversibly until one's brain cannot perform the simplest of tasks, such as sweeping the floor. Dementia is rare in those under 60, and may later present itself as Alzheimer's or as the result of several small strokes. Damage to the blood vessels or nerve structures of the brain can also lead to dementia. As many as 6.8 million Americans have dementia, 1.8 million among them are considered to be severely affected.
"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 co-author Dr. Vincenzo Solfrizzi, a researcher of geriatrics at the University of Bari.
Using participants from the Italian Longitudinal Study on Aging (ILSA), which ran from 1992 to 1996 and examined the rates of common chronic conditions in 65- to 84-year-old Italians, the researchers found that risk factors associated with cardiovascular diseases, such as blood clotting and restricted arteries, influenced the incidence of MCI and the rate of progression to dementia. Since moderate alcohol consumption is linked to improved circulation, the researchers decided to test if drinking may also be associated with the rate of decline of mental health. ILSA participants filled out questionnaires on their drinking habits and underwent physical and mental exams. They were examined again three and a half years later.
The 1,445 participants were categorized by whether they abstained, had up to 1 drink per day, had 1 to 2 drinks per day, or consumed more than 2 drinks a day. Eighty-five percent of the participants reported that they prefer wine. The researchers evaluated the incidence of MCI by administering tests that measured the ability to perform daily tasks focused on self care, such as bathing or preparing their own meals. They also tested attention, language versatility and verbal retention and recall. They also tested more advanced skills, such as the ability to balance a checkbook or going grocery shopping.
The researchers then followed 121 people with MCI and charted their progression to dementia. Those who had up to one drink of alcohol per day developed dementia at an 85 percent slower rate than people who never drank alcohol. Those who drank one to two drinks declined at a rate that was 53 percent slower. The rate was 56 percent slower in those who drank more than two drinks per day, when compared to abstainers.
"This implies that light to moderate alcohol consumption might have a protective effect versus total abstention or heavy consumption," wrote the study's authors. However, they aren't exactly sure why moderate consumption was beneficial.
"The mechanism responsible … isn't known," said Solfrizzi. "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."
But he also noted the limitations of the study. For instance, wine drinkers tend to be more socially active and, therefore, are more active mentally and physically. Furthermore since the research relied on self-reporting among people with MCI, it's difficult to say for certain that everything they wrote on their surveys was accurate.
The authors added that the wine drinkers also followed a Mediterranean-type diet, which includes the moderate consumption of wine, and was associated with a 40 percent lower risk of cognitive decline in a study of a population of New Yorkers. These new findings also echo a previous Italian study that found drinking wine may help reduce the risk of dementia.