Scientists Link Cannabis to Stroke—and Casual Users Aren’t Off the Hook

People who regularly use cannabis might be taking a chance with their cardiovascular health, new research suggests. Scientists at Tulane University studied nationally representative survey data, finding that people who reported using cannabis were significantly more likely to also report having had cardiovascular disease, particularly stroke, than those who didn’t use cannabis. This study doesn’t conclusively show that cannabis can cause cardiovascular problems, but it’s the latest bit of concerning data pointing in that direction. A concerning link Several studies have previously found a connection between cannabis use and cardiovascular disease, though this research hasn’t been entirely consistent. Given that cannabis use has risen substantially in recent years, thanks to increasing recreational legalization, the researchers wanted to get an updated picture of the situation. To do so, they analyzed data from the Behavioral Risk Factor Surveillance System (BRFSS), a longstanding annual survey of Americans’ health trends and habits managed by the Centers for Disease Control and Prevention. They looked at BRFSS data collected between 2020 and 2024, which collectively included nearly a half million adult respondents. Compared to non-tokers, people who regularly used cannabis—whether once a month or daily—were around 20% more likely to report a history of any cardiovascular issues, the study showed. This added associated risk didn’t differ much between people who used cannabis occasionally (one to five days a month) and heavy cannabis users (16 to 30 days a month). Interestingly enough, however, the risk of stroke in particular was higher among less frequent cannabis users (40% higher) than among heavy users (25% higher). The researchers also did not see a clear link between the amount of cannabis use reported and a higher risk of reported heart attacks. The team’s findings were presented over the weekend at the American Heart Association’s Scientific Sessions, the organization’s annual conference. “We were surprised to find that the link between cannabis use and cardiovascular disease was not straightforward. We expected that the chances of heart disease would gradually rise as people used cannabis more often, but that wasn’t the case. Both low-use and heavy-use groups had higher odds of developing heart disease,” said study author Aabha Divya, an assistant professor in the division of cardiothoracic surgery at Tulane University’s School of Medicine, in a statement from the AHA. What to know about this potential risk The team’s findings are preliminary, meaning they haven’t yet undergone the typical peer review process. And this research can only show a correlation between cannabis and cardiovascular disease, not a definitive smoking gun. At the same time, multiple lines of evidence have suggested that cannabis isn’t necessarily harmless to our hearts and blood vessels. Just last month, for instance, a study found that increasing recreational cannabis legalization in the U.S. was linked to higher rates of hospitalization from cardiovascular disease, including heart attacks. There’s still a lot we don’t understand about this potential connection, including whether the form of cannabis you use is relevant at all. In this study, for instance, it didn’t seem to matter whether people primarily used cannabis by smoking it or with edibles, and other studies have suggested that either smoking or eating cannabis can negatively affect blood vessel function. Regardless of the unknowns, however, the researchers say that people and their doctors should be aware of the link. “As cannabis use becomes more common, it is increasingly important that people and their healthcare professionals include it in conversations about cardiovascular health, just as they discuss tobacco, alcohol and other commonly used substances,” Divya said.