A drink or two a day may be associated with better cognitive function in women, according to a report from an ongoing study of New York City residents. The report was published in the rapid access issue of Stroke, Journal of the American Heart Association.
"Women who had up to two drinks a day scored about 20 percent higher on the Mini Mental State Exam (MMSE) than women who didn't drink at all or who consumed less than one drink a week," said Clinton Wright, M.D., M.S., lead author of the study and assistant professor of neurology at the College of Physicians and Surgeons of Columbia University in New York. "The difference remained after adjusting for risk factors such as income, marital status, race or ethnicity and other vascular risk factors such as high blood pressure and cardiac disease."
The researchers said they were surprised by the lack of association between carotid plaque and alcohol consumption. Other research had suggested that alcohol consumption might slow the progression of plaque, the fatty material that builds up in arteries and increases the risk of heart attack and stroke.
"This study suggests that the relationship between alcohol and cognition was not mediated by large vessel atherosclerosis," Wright said. "Future studies with brain imaging are planned to examine the importance of small vessel disease in this relationship."
The fact that the study did not find an association between alcohol consumption and cognition in men might be the result of the sample size since there was "only a small group of men who were never drinkers, so it may not have been possible to detect an effect in men," Wright said.
Study participants were enrolled in the Northern Manhattan Study, an ongoing study of 3,298 stroke-free residents of Northern Manhattan selected by a random digit dialing protocol. This study was conducted in a subsample of 2,215 participants with both alcohol and carotid plaque data available. Their average age was 69. Fifty-four percent of the participants were Hispanic, 25 percent black and 21 percent white.
The ethnicity of the participants was important, as only a few previous studies have included blacks or Hispanics, who have higher rates of cerebrovascular disease, dementia and Alzheimer's disease.
Researchers assessed alcohol intake in structured interviews, while carotid artery plaque was measured by carotid ultrasound.
"It was important for this study that all of the participants lived in the area of the same city, so they would all be subject to the same environmental influences," Wright said.
The participants were divided into five groups based on alcohol consumption: