Objective: to investigate prospectively the relationship between current alcohol consumption (quantity and type of alcohol) and incident overall dementia and Alzheimer dementia.
Method: the study is based on individuals (75+) attending general practitioners in Germany: 3,202 subjects free of dementia were studied at baseline, 1.5 years and 3 years later by means of structured clinical interviews including detailed assessment of current alcohol consumption and DSM-IV dementia diagnoses. Associations between alcohol consumption (in grams of ethanol), type of alcohol (wine, beer, mixed alcohol beverages) and incident dementia were examined using Cox proportional hazard models, controlling for several confounders.
Results: incident overall dementia occurred in 217 of 3,202 participants over a mean follow-up period of 3 years. Significant relationships were found between alcohol consumption (prevalence at baseline: 50.0%) and incident overall dementia (adjusted hazard ratio (HR) 0.71, 95% CI 0.53-0.96), respectively, incident Alzheimer dementia (adjusted HR 0.58, 95% CI 0.38-0.89). With regard to quantity of alcohol and type of alcohol, all hazard ratios were found to be lower than 1.
Conclusion: in agreement with meta-analyses that include younger age groups, our study suggests that light-to-moderate alcohol consumption is inversely related to incident dementia, also among individuals aged 75 years and older.