We all know that light-to-moderate alcohol consumption may help lower the risk of coronary heart disease, ischemic stroke and total mortality, but did you also know that it might reduce the risk for dementia? Because vascular disease has been linked to the development of cognitive impairment and dementia, researchers from the Rotterdam Study decided to test the hypothesis that alcohol consumption might affect the risk of dementia.
Cognitive impairment at baseline and data on alcohol consumption were obtained for 5,395 patients, aged 55 and older, with almost complete follow-up (99.7%) an average of six years later. A number of baseline variables were used as possible confounders, including age, sex, diabetes, systolic blood pressure, education, smoking and body-mass index.
During the study, 197 individuals developed dementia--146 Alzheimer disease, 29 vascular dementia and 22 other dementia. Light-to-moderate alcohol consumption (defined as one to three drinks per day) was significantly associated with a lower risk of any dementia and vascular dementia. Interestingly, the results did not appear to be influenced by the type of alcohol consumed. The authors suggest that alcohol might act to reduce cardiovascular risk factors, supported by the fact that lower risk was seen mainly for vascular dementia, or may have a direct effect on cognition through alcohol-induced release of acetylcholine in the hippocampus.
Authors acknowledge that one limitation of the study is that the alcohol consumption data were based on a semiquantitative food-frequency questionnaire. Although these are highly reproducible, both under and over-reporting are possible.
- Ruitenberg A, van Swieten JC, Witteman JCM, et al. Alcohol consumption and risk of dementia: the Rotterdam study. Lancet 2002; 359:281-6.