Heavy Alcohol Use Linked to Early-Onset Dementia: Study

The hazards of too much booze are well documented, as research has shown that heavy drinkers open themselves up to liver disease, heart problems, cancer—and the early onset of dementia, according to a new study.

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The World Health Organization estimates cases of dementia—progressive cognitive deterioration—will triple by 2050, spurring researchers to identify ways to limit risk. People with dementia lose some cognitive ability that helps with memory and thinking to the point that it interferes their normal activities. However, the severity ranges for each case.

Published in The Lancet Public Health journal, the latest findings show that excessive drinkers were more likely to develop early-onset dementia. The link between alcohol and dementia risk is not new: A review of 72 studies on alcohol and cognitive function published in the International Journal of High Risk Behaviors and Addiction in 2016 concluded long-term heavy drinking causes brain damage.

But this particular finding surprised others in the medical community.

Psychiatrist Richard Rosenthal of Stony Brook Medicine called the discovery glaring. He was not involved with the study and explained to Newsweek that earlier research hinted at how heavy drinking could lead to dementia, but the sheer numbers used in this study make the findings significant.

"This really was kind of a slam dunk in terms of the huge data set," he said. "It really made [alcohol] a very striking risk factor."

Using data from French hospitals, a team of European researchers looked at more than 1 million people who were diagnosed with dementia and had been discharged from the hospital between 2008 and 2013. Anyone over the age of 20 who did not have medical conditions associated with dementia, like Parkinson's disease, was included.

The most startling discovery is that about 57 percent of those who developed early-onset dementia—defined as before the age of 65—were chronically heavy drinkers. The extent of drinking varied per person, and Rosenthal said alcohol abuse is measured differently in France. However, the Centers for Disease Control and Prevention defines heavy drinking as 15 or more drinks a week for men, and eight or more for women.

The team also found that while women suffered more overall from dementia, about 64 percent from the data, more men developed early-onset dementia, about 64 percent of all early diagnosis were given to males.

Rosenthal said that's not entirely surprising given that more men than women usually report having substance-abuse problems. It's natural to conclude that people who have unhealthy drinking habits exhibit other unhealthy behaviors, but the team controlled for factors that could contribute to the disease, such as smoking and high blood pressure, and found that excessive drinking was still significant in elevating risk. Even after abstaining from alcohol, people who were once heavy drinkers were still at an increased risk of developing dementia, indicating that damage was not reversible.

Rosenthal said it takes about a year of omitting alcohol to reverse some of the damage, but says it's unlikely to recover completely.

"Some portion of physical or chemical injury to the brain is reversible," he said. "But probably some stuff doesn't get better."

Despite the impressive data set, it's important to remember that no causal relationship was shown. However, Rosenthal thinks this study offers one major takeaway.

"Alcohol is a toxin," he said. "People need to be advised about that and understand that better."

He says that you don't need to give up drinking completely. In fact, Rosenthal referred to prior studies that indicated moderate drinkers have less risk of developing the disease than those who don't consume any alcohol. But he strongly recommends saving your booze for special occasions or limiting how many glasses of wine you have at dinner.