Frequent Cannabis Use Associated with Higher Risk of Coronary Artery Disease

Daily users of marijuana were found to be 34% more likely to have coronary artery disease (CAD) than never-users in a Mendelian randomization study to be presented at the American College of Cardiology’s (ACC) 72nd Annual Scientific Session Together With the World Congress of Cardiology, being held March 4-6, 2023, in New Orleans.

“We found that cannabis use is linked to CAD, and there seems to be a dose-response relationship in that more frequent cannabis use is associated with a higher risk of CAD,” said lead author Ishan Paranjpe, MD, resident physician, Stanford University, in an ACC press release. “In terms of the public health message, it shows that there are probably certain harms of cannabis use that weren’t recognized before, and people should take that into account.”

The current study is one of the largest and most comprehensive to date to analyze the potential long-term cardiovascular effects of marijuana use. Previous research has reported conflicting evidence on the association of cannabis use and CAD, with some suggesting that marijuana consumption can increase the risk of myocardial infarction, stroke, and other cardiac events, particularly in younger persons.

Using data from the All of Us Research Program of the National Institutes of Health, which includes detailed information about the health and habits of 175 000 people, Paranjpe and colleagues first analyzed the association between cannabis use frequency (assessed using surveys at the time of enrollment) and rates of CAD (assessed based on medical records spanning several years). Then, the research team performed a Mendelian randomization analysis using summary statistics from genome wide association studies of cannabis use disorder (CUD) and lifetime cannabis use, according to the study abstract.

Results

After adjusting for age, sex, hypertension, hyperlipidemia, type 2 diabetes, body mass index, education, insurance status, and cigarette use, investigators observed that daily marijuana users (N=4736) had an increased odds of developing CAD (odds ratio [OR] 1.34, 95% CI, 1.13-1.58, P=.001) compared to those who never used marijuana.

Using 2-sample Mendelian randomization, genetic liability to CUD was associated with an increased risk of CAD (OR 1.05, 95% CI, 1.02-1.09, P=.001). There was no evidence of pleiotropy, outliers, or violation of Mendelian randomization assumptions, authors added in the abstract. The association of CUD and CAD was independent of alcohol and tobacco use in multivariable Mendelian randomization analysis (OR 1.04, 95% CI, 1.01-1.07).

The datasets used in the current study did not differentiate between different forms of cannabis consumption (eg, consumed in edible form or smoked). Since tetrahydrocannabinol, the molecule responsible for the psychoactive effects of cannabis, enters the body through a different pathway and gets to the brain more quickly when marijuana is smoked rather than eaten, researchers noted that it would be helpful to assess the health implications of these varying forms of cannabis intake in future studies.

Paranjpe will present the study, “Association of cannabis use disorder with risk of coronary artery disease: A Mendelian randomization study,” on Sunday, March 5, 2023, at 9:30 am CT / 15:30 UTC in Poster Hall, Hall F.