Research published in the Lancet Public Health journal shows that the majority of cases of early-onset dementia in people below the age of 65 were either alcohol-related by definition or accompanied by alcohol use disorders.
Of the 57,000 cases studied, 39 per cent were alcohol-related by definition while 18 per cent had an alcohol use disorder as an additional diagnosis.
Chronic heavy drinking is defined as consuming more than 60g of pure alcohol a day for men – equivalent to around six standard drinks per day on average – and more than 40g per day for women – around four standard drinks per day.
Lead author Dr Michaël Schwarzinger, of the Translational Health Economics Network in France, said that while the link between dementia and alcohol use needed further research, it was likely a result of alcohol leading to “permanent structural and functional brain damage”.
He continued: “Alcohol use disorders also increase the risk of high blood pressure, diabetes, stroke, atrial fibrillation, and heart failure, which may in turn increase the risk of vascular dementia.
“Lastly, heavy drinking is associated with tobacco smoking, depression, and low educational attainment, which are also risk factors for dementia.”
The study used data from the French National Hospital Discharge database, which holds details on all hospital admissions, including patient demographics, reasons for hospital stay, and treatments received.
Overall, alcohol use disorders were associated with a three times greater risk of all types of dementia and were the strongest modifiable risk factor for dementia onset, the researchers said.
Dr Schwarzinger added: “Our findings suggest that the burden of dementia attributable to alcohol use disorders is much larger than previously thought, suggesting that heavy drinking should be recognised as a major risk factor for all types of dementia.
"A variety of measures are needed, such as reducing availability, increasing taxation, and banning advertising and marketing of alcohol, alongside early detection and treatment of alcohol use disorders.”
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