Summary: According to researchers, alcohol use disorder poses an increased risk for the early development of dementia.
Alcohol use disorders are the most important preventable risk factors for the onset of all types of dementia, especially early-onset dementia. This according to a nationwide observational study, published in The Lancet Public Health journal, of over one million adults diagnosed with dementia in France.
This study looked specifically at the effect of alcohol use disorders, and included people who had been diagnosed with mental and behavioural disorders or chronic diseases that were attributable to chronic harmful use of alcohol.
Of the 57,000 cases of early-onset dementia (before the age of 65), the majority (57%) were related to chronic heavy drinking.
The World Health Organization (WHO) defines chronic heavy drinking as consuming more than 60 grams pure alcohol on average per day for men (4-5 Canadian standard drinks) and 40 grams (about 3 standard drinks) per day for women.
As a result of the strong association found in this study, the authors suggest that screening, brief interventions for heavy drinking, and treatment for alcohol use disorders should be implemented to reduce the alcohol-attributable burden of dementia.
“The findings indicate that heavy drinking and alcohol use disorders are the most important risk factors for dementia, and especially important for those types of dementia which start before age 65, and which lead to premature deaths,” says study co-author and Director of the CAMH Institute for Mental Health Policy Research Dr. Jürgen Rehm. “Alcohol-induced brain damage and dementia are preventable, and known-effective preventive and policy measures can make a dent into premature dementia deaths.”
Dr. Rehm points out that on average, alcohol use disorders shorten life expectancy by more than 20 years, and dementia is one of the leading causes of death for these people.
For early-onset dementia, there was a significant gender split. While the overall majority of dementia patients were women, almost two-thirds of all early-onset dementia patients (64.9%) were men.
Alcohol use disorders were also associated with all other independent risk factors for dementia onset, such as tobacco smoking, high blood pressure, diabetes, lower education, depression, and hearing loss, among modifiable risk factors. It suggests that alcohol use disorders may contribute in many ways to the risk of dementia.
“As a geriatric psychiatrist, I frequently see the effects of alcohol use disorder on dementia, when unfortunately alcohol treatment interventions may be too late to improve cognition,” says CAMH Vice-President of Research Dr. Bruce Pollock. “Screening for and reduction of problem drinking, and treatment for alcohol use disorders need to start much earlier in primary care.” The authors also noted that only the most severe cases of alcohol use disorder – ones involving hospitalization – were included in the study. This could mean that, because of ongoing stigma regarding the reporting of alcohol-use disorders, the association between chronic heavy drinking and dementia may be even stronger.
About this neuroscience research article
This study received no funding. It was conducted by researchers from Translational Health Economics Network (THEN); UMR 1137 INSERM–Université Paris Diderot, Sorbonne Paris Cité; Centre for Addiction and Mental Health, University of Toronto; INSERM, University of Bordeaux, Centre INSERM U1219-Bordeaux Population Health, ISPED-Bordeaux School of Public Health.
[cbtabs][cbtab title=”MLA”]CAMH “Alcohol Use Biggest Risk Factor for Dementia.” NeuroscienceNews. NeuroscienceNews, 21 February 2018. <https://neurosciencenews.com/alcohol-dementia-risk-8536/>.[/cbtab][cbtab title=”APA”]CAMH (2018, February 21). Alcohol Use Biggest Risk Factor for Dementia. NeuroscienceNews. Retrieved February 21, 2018 from https://neurosciencenews.com/alcohol-dementia-risk-8536/[/cbtab][cbtab title=”Chicago”]CAMH “Alcohol Use Biggest Risk Factor for Dementia.” https://neurosciencenews.com/alcohol-dementia-risk-8536/ (accessed February 21, 2018).[/cbtab][/cbtabs]
Contribution of alcohol use disorders to the burden of dementia in France 2008–13: a nationwide retrospective cohort study
Background Dementia is a prevalent condition, affecting 5–7% of people aged 60 years and older, and a leading cause of disability in people aged 60 years and older globally. We aimed to examine the association between alcohol use disorders and dementia risk, with an emphasis on early-onset dementia (<65 years).
Methods We analysed a nationwide retrospective cohort of all adult (≥20 years) patients admitted to hospital in metropolitan France between 2008 and 2013. The primary exposure was alcohol use disorders and the main outcome was dementia, both defined by International Classification of Diseases, tenth revision discharge diagnosis codes. Characteristics of early-onset dementia were studied among prevalent cases in 2008–13. Associations of alcohol use disorders and other risk factors with dementia onset were analysed in multivariate Cox models among patients admitted to hospital in 2011–13 with no record of dementia in 2008–10.
Findings Of 31 624 156 adults discharged from French hospitals between 2008 and 2013, 1 109 343 were diagnosed with dementia and were included in the analyses. Of the 57 353 (5·2%) cases of early-onset dementia, most were either alcohol-related by definition (22 338 [38·9%]) or had an additional diagnosis of alcohol use disorders (10 115 [17·6%]). Alcohol use disorders were the strongest modifiable risk factor for dementia onset, with an adjusted hazard ratio of 3·34 (95% CI 3·28–3·41) for women and 3·36 (3·31–3·41) for men. Alcohol use disorders remained associated with dementia onset for both sexes (adjusted hazard ratios >1·7) in sensitivity analyses on dementia case definition (including Alzheimer’s disease) or older study populations. Also, alcohol use disorders were significantly associated with all other risk factors for dementia onset (all p<0·0001).
Interpretation Alcohol use disorders were a major risk factor for onset of all types of dementia, and especially early-onset dementia. Thus, screening for heavy drinking should be part of regular medical care, with intervention or treatment being offered when necessary. Additionally, other alcohol policies should be considered to reduce heavy drinking in the general population.