The findings are the first to show gender differences in the effect alcohol has on brain "shrinkage" that is common in all long-time heavy drinkers or alcoholics. Previous studies have shown that women are also more prone to liver and heart damage than male alcoholics.
"We're showing that the brain is basically the same as these organs," lead author Dr. Daniel W. Hommer told the press.
In the Hommer study, the researchers examined brain scans of 79 male and female alcoholics after three weeks of abstinence and compared the brain volumes with those of 39 healthy study participants. The researchers found that while male alcoholics showed signs of brain "shrinkage" compared with healthy men, the difference between alcoholic and healthy women was much greater, indicating the killing of brain cells.
Smaller Brain VolumeAlcoholic women showed an 11 percent smaller brain volume than healthy women. The study reported that such a difference would be unlikely to make a significant change in mental capacity and none of the study participants, with an average age of 40, showed signs of mental deficits.
However, Hommer told reporters, "Brain shrinkage increases with age in all people. The early decreases seen in alcoholics may make them more vulnerable to cognitive decline and dementia as they grow older."
"Alcoholism is linked to dementia," he said and this study, suggests that alcoholic women may be particularly at risk. Hommer and his colleagues at the National Institute on Alcohol Abuse and Alcoholism in Bethesda, Maryland reported their findings in the February 2001 issue of the American Journal of Psychiatry.
However, another California study, published in the February issue of Alcoholism: Clinical & Experimental Research, indicated that thinking and cognitive abilities in women alcoholics is affected by heavy drinking.
In that study, researchers tested participants for cognitive (or thinking) abilities and mood before examining their functional MRI (fMRI), and tested their working memory abilities both before and during the fMRI.
Even Young Women at Risk"The main finding," said Susan F. Tapert, first author of the study, in a news release, "was that the alcohol-dependent women showed less activation in brain areas that are needed for spatial tasks like puzzles, maps and mechanics, and for working with information that is held mentally, like doing math inside your head or making sense of a lecture or set of complex instructions. The brain parts that showed the differences are in areas that we need for finding our way around, and working with all the information we are bombarded with in everyday life."
Tapert said her findings suggest that even young and physically healthy individuals, particularly if they are female, risk damaging their brains through chronic, heavy use of alcohol.
"Compared with the non alcoholics," said Edith V. Sullivan, associate professor of psychiatry at Stanford University School of Medicine, "the young women with alcohol dependence appeared to engage their cortical systems less vigorously. In some cases, the brain systems activated by the alcoholic women were different from those activated by individuals with no alcohol problems."
"One interpretation of these differences is that the alcoholic women tend to invoke brain systems that are less appropriately tuned for the task at hand, or perhaps the activation is not as intense as it might be without their history of alcohol dependence," Sullivan said.
"The Tapert study has demonstrated that even young women with alcohol dependence suffer significant aberrations in brain and cognitive function and that this pattern of abnormalities is similar to that documented in older alcoholics with many years of abusive drinking," Sullivan said.