While past research has hinted at the connection between heavy alcohol use and vascular aging in the brain, Gurol notes that most earlier studies lacked detailed imaging to reveal the biological mechanisms behind why. “This is the largest study to include CAT scans of the brain in all patients and MRIs in about 75 percent,” Gurol says. This allowed the team to identify structural brain changes and better understand the ways alcohol contributes to bleeding risk.
Clifford Segil, a neurologist at Providence Saint John’s Health Center in Santa Monica who was not involved in the research, says the findings make clear that heavy alcohol users who experience bleeds “are going to get bigger bleeds, and their potential for recovery will be decreased due to alcohol’s effects on blood pressure and platelet levels.”
Such findings, adds Sheth, “are timely and clinically relevant.”
The takeaway
But like all observational research, the study cannot prove cause and effect. “Randomized controlled trials—the gold standard for proving causation—aren’t feasible when studying heavy drinking because we obviously can’t assign people to drink heavily to see how it causes harm,” Gurol explains.
The team also relied on self-reported alcohol use, which can be unreliable. “It’s possible that some heavy drinkers—or their families—may have underreported alcohol use, meaning a few could have been misclassified as non-heavy drinkers,” Gurol says. “That kind of underreporting would likely dilute the true impact, so the real effect may be even stronger than what we observed.”