Alcohol linked to brain shrinkage

Oct 15 2008

According to the latest research drinking alcohol shrinks the brain and the more alcohol an individual drinks, the smaller his or her total brain volume will be.

The U.S. researchers say people who drink more than two glasses of wine a day are at a greater risk of suffering memory problems in old age than non drinkers and drinking more than 14 alcoholic drinks a week speeds up the normal process whereby the brain shrinks with age.

Their study shows that the brains of people who drank more than two drinks a day shrunk by a quarter more than non-drinkers - brain shrinkage has been linked to memory problems and the onset of dementia.

Experts say it is normal for brain volume to decrease with age, which happens at an estimated rate of 1.9% per decade.

This accompanied by an increase in white matter lesions, lowers the brain's volume - larger white matter lesions also occur with the progression of dementia and problems with thinking, learning and memory.

While moderate alcohol consumption has been associated with a lower risk of cardiovascular disease, because the brain receives blood from this system, the researchers suspected that small amounts of alcohol may also affect age-related declines in brain volume.

Dr. Carol Ann Paul, from of Wellesley College, Massachusetts and her colleagues conducted a study of 1,839 adults with an average age 60, who were part of the Framingham Offspring Study - this major study began in 1971 and includes children of the original Framingham Heart Study participants and their spouses.

Between 1999 and 2001, participants underwent magnetic resonance imaging (MRI) and a health examination and also reported the number of alcoholic drinks they drank each week, along with their age, sex, education, height, body mass index and Framingham Stroke Risk Profile, which calculates stroke risk based on age, sex, blood pressure and other factors.

The researchers say most participants reported low alcohol consumption, and men were more likely than women to be moderate or heavy drinkers, but they say there was a significant negative linear relationship between alcohol consumption and total cerebral brain volume.

It was also noticeable that although men were more likely to drink alcohol, the association between drinking and brain volume was stronger in women, which could be due to biological factors, including women's smaller size and greater susceptibility to alcohol's effects.

The researchers say the study gives a clear message about the possible dangers of drinking alcohol and suggest that prospective longitudinal studies are needed to confirm these results as well as to determine whether there are any functional consequences associated with increasing alcohol consumption.

The study suggests that, unlike the associations with cardiovascular disease, alcohol consumption does not have any protective effect on brain volume.

The research is published in the current issue of Archives of Neurology, one of the JAMA/Archives journals.