To examine the association between alcohol use disorder (AUD) and risk of dementia, this study used a nationwide retrospective cohort of all adults aged ≥20 years admitted to a hospital in metropolitan France between 2008 and 2013. Researchers also examined subtypes of dementia: early onset dementia (defined as diagnosis before age 65), alcohol-related brain damage, vascular dementia, and other dementia (including Alzheimer’s disease). Covariates were: vascular risk factors, presence of cerebrovascular disease or cardiovascular disease, education level, depression, hearing loss, visual impairment, sleep apnea, and diseases likely to lead to rare forms of dementia (e.g. uremia).
- AUD was associated with an increased risk of dementia (hazard ratio [HR], 3.34 for women and 3.36 for men); those HRs were higher than those for any other risk factor (e.g. high blood pressure [HR, 1.43 for women and 1.35 for men]).
- AUD was associated with an increased risk of each dementia type. Of the 57,353 (5%) cases of early onset dementia, most were either alcohol-related by definition (i.e., alcohol brain damage, 39%) or had a diagnosis of AUD (18%).
Comments: In contrast with studies suggesting potential benefits of light drinking, this study adds to the evidence of a detrimental effect of alcohol on brain function. Alcohol use disorder was the strongest potentially modifiable risk factor of dementia in this study; these results suggest a burden of dementia attributable to alcohol more important than previously thought.
Nicolas Bertholet, MD, MSc
Reference: Schwarzinger M, Pollock BG, Hasan OSM, et al. Contribution of alcohol use disorders to the burden of dementia in France 2008-13: a nationwide retrospective cohort study. Lancet Public Health. 2018;3(3):e124–e132.