Cannabis Use Associated with Higher Heart Attack and Stroke Risk, Study Finds

Cannabis use  — whether smoked, eaten or vaporized — is associated with a higher number of adverse cardiovascular outcomes, according to a new study.

Published Wednesday in the Journal of the American Heart Association, researchers found that risk of coronary heart disease, heart attack and stroke increased with any kind of cannabis use, with heavier use associated with higher odds of negative outcomes.

For daily cannabis users, for example, odds of a heart attack were 25% higher compared to non-users and 42% higher for stroke, the study found. 

"Despite common use, little is known about the risks of cannabis use and, in particular, the cardiovascular disease risks," lead author Abra Jeffers, a data analyst at Massachusetts General Hospital in Boston, said in a news release. "The perceptions of the harmfulness of smoking cannabis are decreasing, and people have not considered cannabis use dangerous to their health. However, previous research suggested that cannabis could be associated with cardiovascular disease. In addition, smoking cannabis — the predominant method of use — may pose additional risks because particulate matter is inhaled."

The cross‐sectional study used survey data from 430,000 adults in the U.S. spanning from 2016 to 2020 with participants aged 18 to 74. The data also allowed them to control for other cardiovascular risk factors and tobacco use, showing a similar association was true even among never‐tobacco smokers.

"Our sample was large enough that we could investigate the association of cannabis use with cardiovascular outcomes among adults who had never used tobacco cigarettes or e-cigarettes," Jeffers said. "Cannabis smoke is not all that different from tobacco smoke, except for the psychoactive drug: THC vs. nicotine. Our study shows that smoking cannabis has significant cardiovascular risks, just like smoking tobacco. This is particularly important because cannabis use is increasing, and conventional tobacco use is decreasing."

Since this study did have some limitations, including heart conditions and cannabis use being self-reported, researchers are calling for more research that follow groups of individuals over time.

For now, the study "adds to the growing literature that cannabis use and cardiovascular disease may be a potentially hazardous combination," Robert L. Page, professor at the Skaggs School of Pharmacy and Pharmaceutical Sciences at the University of Colorado School of Medicine, said in the release.

The findings should also be a "call to action for all practitioners," added Page, who was not involved in the study.