Chronic alcohol users could put themselves at a three-times greater risk of developing dementia, according to a new study published in the Lancet Public Health journal.

The study – the largest of its kind – found that alcohol use disorders are the most preventable factors for the onset of all types of dementia. The observational study analyzed data from more than 1 million patients admitted to hospitals in metropolitan France with a dementia diagnosis between 2008 and 2013.

More specifically, the study authors focused on patients who had been diagnosed with mental and behavioral disorders, or chronic diseases that were attributable to chronic harmful use of alcohol, according to a release on the findings from the Centre for Addiction and Mental Health.

The study identified 57,353 people who had cases of early-onset dementia (before age 65). Thirty-eight percent of the cases were directly related to chronic heavy alcohol consumption and 18 percent had an additional diagnosis of alcohol use disorders.

Overall, alcohol use disorders were associated with a three times greater risk of all types of dementia.

But 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 percent) were men, according to the study.

"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 Jürgen Rehm, study co-author and director of the CAMH Institute for Mental Health Policy Research.

The study also found that alcohol use disorders were 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. This suggests that alcohol use disorders can contribute in a variety of ways to the risk of dementia.

Previous reports have shown a beneficial link between low to moderate drinking – particularly red wine consumption – and brain health. But the latest study emphasizes that escalating to heavy drinking habits can have detrimental consequences.

“At first glance, these findings might appear inconsistent with other reports, including some that made the news very recently, that low to moderate drinking is associated with better ‘cognitive health.’  These findings can be reconciled because there is a big difference between low to moderate drinking, and alcohol use disorder,” explained Matt Field, professor of addiction at the University of Liverpool, who was not involved in the study. “However, both types of research are subject to the usual limitations of observational studies: they cannot definitely establish cause and effect, and any observed relationships are almost certainly confounded by other factors, not all of which can be easily measured.”

The study authors believe the findings are strong enough to advise that screenings for heavy drinking, and treatment for alcohol use disorders should be implemented to reduce the alcohol-attributable burden of dementia.

There are several types of dementia -- Alzheimer’s disease being the most common, followed by vascular dementia. Overall, the condition of dementia affects five to seven percent of people worldwide ages 60 years and older, and is a leading cause of disability for people in this age group.