In the study, researchers looked at 43,000 adults ages 18 to 44 who had used marijuana within the last 30 days — finding “significantly higher odds of stroke” in young cannabis users as compared with nonusers. The risk was even higher in frequent users: Those who reported using weed more than 10 days a month were 2.5 times more likely to have a stroke than nonusers.

Additional forms of smoking, including vaping, only appear to make things worse: Young people who both used marijuana frequently and used e-cigarettes or smoked cigarettes were three times more likely to suffer a stroke compared to nonusers.

The research also found that people diagnosed with cannabis use disorder — a form of dependence on marijuana — were more likely to be hospitalized for heart rhythm problems known as arrhythmias.