A new study estimates that more than 2 million adults with cardiovascular disease have smoked marijuana, yet there’s been a dearth of research on the effects of cannabis on heart disease.
After doing an extensive review of the research, the authors of the study reported that there’s enough preliminary evidence to suggest that smoking or vaping marijuana may pose risks to these patients, including abnormal heart rhythms, weakening of the heart muscle, heart attacks, and stroke.
The study, published in the Journal of the American College of Cardiology, analyzed existing research including a meta-analysis that found that the top three triggers of heart attack were cocaine, eating a heavy meal, and smoking marijuana (though the research didn’t specify the effects of indica- versus sativa-dominant strains). Past studies have shown that cannabis does increase your heartrate and experts have advised heart patients to use edibles rather than smoking marijuana because inhaling toxins is harmful to the lungs and heart.
“Our review suggests that smoking marijuana carries many of the same cardiovascular health hazards as smoking tobacco,” said one of the study’s authors, Muthiah Vaduganathan, MD, MPH, a cardiologist at Brigham and Women’s Hospital’s Heart and Vascular Center. “We advise caution regarding the use of marijuana in our highest-risk patients with established cardiovascular disease,” he said.
The authors reviewed the National Health and Nutrition Examination Survey from 2005 through 2016 and found that 89.6 million adults reported using marijuana. Among cannabis-users, 2 million (2.3%) had cardiovascular disease.
The authors lamented the fact that there’s very little research on the health effects of marijuana because the drug is a schedule I substance, which limits its availability for research purposes. Cardiologists need research on the direct risks of cannabis as well as how medications interact with marijuana. The authors described potential interactions of cannabinoids with several types of cardiovascular drugs, including antiarrhythmics, calcium-channel blockers, statins, beta-blockers, and warfarin.
“As cardiologists, we should be open and honest with patients, sharing that while the scientific evidence to date is only modest and incomplete, there are definite signals of cardiovascular harm associated with marijuana that we cannot ignore,” said Vaduganathan.