Their findings are published online in The Lancet Public Health.
“Alcohol-related dementia should be recognized as one of the main causes of early-onset dementia,” researchers wrote. “Additionally, clinicians should be better aware of the role of alcohol use disorders in dementia onset over the lifetime, which seems to be a risk factor often omitted.”
The findings stem from an analysis of 1.1 million adults in France discharged from hospitals with a dementia diagnosis between 2008 and 2013. Of the 57,353 adults with early-onset dementia, 57% of the cases were linked with chronic heavy drinking, researchers found.
“Alcohol use disorders were the strongest modifiable risk factor for dementia onset,” researchers wrote, “with an adjusted hazard ratio of 3.34 for women and 3.36 for men.”
Because the study included only severe cases of alcohol use disorder involving hospitalization, researchers suspect the association between heavy drinking and dementia may be even stronger than findings suggest.
“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,” said study co-author Jürgen Rehm, PhD, of the Centre for Addiction and Mental Health in Toronto, Canada.
“Alcohol-induced brain damage and dementia are preventable, and known-effective preventive and policy measures can make a dent into premature dementia deaths.”