Alcohol bottles in Broadway Marketplace. By Grace E. Yoon

By Noor Ali, Alma T. Barak, and Christopher Schwarting, Contributing Writers

November 17, 2025

Heavy alcohol consumption may lead to earlier and more severe brain bleeds, according to a study published by researchers at Massachusetts General Brigham earlier this month.

Using data from patients admitted to MGB between 2003 and 2019 who had brain bleeds, the researchers found that people who drank heavily — defined as three or more alcoholic drinks a day — were 11 years younger, on average, when their bleeds occurred.

Strokes can be categorized into two types: ischemic strokes, which occur when blood flow to the brain is blocked, and hemorrhagic strokes, which result from a ruptured blood vessel. The researchers focused on the latter, which typically lead to more severe damage.

“Hemhorrhagic strokes, or brain bleeds, are less common, but they are a lot more dangerous,” said Edip Gurol, an associate professor of neurology at Harvard Medical School and author of the study. “50 percent of people who have a brain bleed die within the first month.”

The study, published in Neurology, tracked 1,600 patients over the course of 16 years, of which seven percent reported heavy alcohol consumption. The median age of brain bleeds for heavy drinkers was 64, compared to 75 in those who did not report heavy alcohol consumption.

“There was a very, very significant difference, which is telling us that one way or the other, heavy drinking is accelerating the brain bleeds,” Gurol said.

Using CT scans to determine the size and location of bleeds, the authors found that heavy drinkers experienced 70 percent larger bleeds and were twice as likely to have a bleed deep inside their brain.

“The brain bleeds in those patients were more likely to be deep and more likely to open inside the spinal fluid-filled spaces, the ventricles of the brain,” Gurol said.

Patients who reported heavy alcohol usage had higher blood pressure and lower blood platelet counts when they were admitted to the hospital, the study found. Those patients also showed greater evidence of small vessel damage in the brain, which is linked to several other health conditions such as dementia and heart failure.

“Despite their younger age, very probably because of the excessive alcohol use, these people had more severe small vessel disease-related brain damage, which is called white matter disease,” Gurol said.

Alvin S. Das, an assistant professor at Beth Israel Deaconess Medical Center, said the finding that heavy drinkers experienced larger brain bleeds would prompt him to stress the importance of cutting back on alcohol to his patients.

“What it might compel me to do is in a patient that comes to my office and they’ve had a deep hemorrhage, not only counsel them on aggressive hypertension management down the road to prevent another hemorrhage, but this study also would push me to counsel alcohol cessation,” Das said.

Because the number of heavy drinkers in the study was small and the data came from a single hospital, the researchers noted that future work should use larger datasets to examine how varying levels of alcohol use affect brain aging and stroke risk.

Gurol, for his part, said the findings underscore the importance of limiting alcohol consumption broadly, even in individuals without pre-existing health conditions.

“Even for people without known risk of alcohol damage, it is probably best to not to exceed three glasses per week and not to exceed one glass in over 24 hours,” Gurol said.

Want to keep up with breaking news? Subscribe to our email newsletter.

Tags

ResearchHarvard Medical School