People who smoke marijuana or eat weed-laced edibles daily are a third more likely to develop coronary artery disease (CAD).
And, according to the authors of a recent study, it doesn’t matter whether you smoke or eat the cannabis, regular consumption could give you a heart attack.
One of the largest studies ever carried out on the long term toll of the drug on the heart revealed that the more you smoke, the higher the risk. The significant link remained regardless of whether users smoked tobacco, drank alcohol, had major cardiovascular risk factors, and no matter their age and sex, reports The Independent.
How often 175 000 participants smoked weed was compared with the rates of CAD diagnosis in the group versus the wider US population.
A genetics-based method of identifying a causal link between using cannabis and developing CAD was applied, and it was found that those who smoked the drug daily were 34% more likely to develop CAD.
Previous studies revealed the psychoactive molecule that gets users “high”, THC (tetrahydrocannabinol), acts on receptors in the central nervous system in the heart and blood vessels. THC’s interaction with blood vessels could inflame the tubes and allow plaque to build up, leading to CAD.
Scientists would not expect the same effects using CBD (cannabidiol).
Meanwhile, decriminalisation in many states means around 18% of adults in the US also use the drug each year.
Cannabis use disorder is a recognised psychiatric disorder involving how often people use the drug, and how dependent they are, and researchers urge the public to realise that smoking weed is not risk free.
Dr Ishan Paranjpe, resident physician at Stanford University and the study’s lead author, said: “There seems to be a dose-response relationship in that more frequent cannabis use is associated with a higher risk of CAD.
“In terms of the public health message, it shows there are probably certain harms of cannabis use that weren’t recognised before, and people should take that into account.
“From a scientific standpoint, these findings are exciting because they suggest there might be new drug targets and mechanisms we can explore to take control of this pathway going forward.”
The American College of Cardiology study team added that people should let their doctors know if they use the drug, so clinicians can start monitoring heart health.
The study was presented last week at the American College of Cardiology’s (ACC) Annual Scientific Session with the World Congress of Cardiology.
Study details
Association of cannabis use disorder with risk of coronary artery disease: a mendelian randomisation study
Ishan Paranjpe, Roy Lan, Suraj Jaladanki, Jagat Narula, Benjamin Glicksberg, Girish Nadkarni, Samir Kamat.
Presented at ACC 2023 on 5 March
Abstract
Background
There is conflicting evidence on the association of cannabis use and coronary artery disease (CAD). We investigated the causal association of genetic liability to cannabis use disorder and risk of CAD.
Methods
Using the All of Us cohort, a large population level cohort from 340 inpatient and outpatient sites across the United States (N = 175,000), we associated cannabis use frequency with CAD. We then performed a mendelian randomisation analysis using summary statistics from genome wide association studies (GWAS) of cannabis use disorder (CUD) and lifetime cannabis use.
Results
Compared to never-users (N = 39,678), daily cannabis users (N= 4,736) had an increased odds of developing CAD (OR = 1.34, 95% CI: 1.13 – 1.58, P = 0.001) adjusted for age, sex, hypertension, hyperlipidemia, type 2 diabetes, body mass index, education, insurance status, and cigarette use. Using two-sample MR, genetic liability to CUD was associated with an increased risk of CAD (OR = 1.05, 95% CI: 1.02 – 1.09, P = 0.001). No evidence of pleiotropy, outliers, or violation of MR assumptions was found. The association of CUD and CAD was independent of alcohol and tobacco use in multivariable MR analysis (OR = 1.04, 95% CI: 1.01 – 1.07).
Conclusion
In a large population-level cohort, frequent but not occasional cannabis use was associated with an increased risk of CAD. In MR analysis, CUD, but not occasional use was associated with CAD, independent of tobacco use.
See more from MedicalBrief archives:
Marijuana edibles a major risk to patients with cardiovascular disease
Higher lung damage risk for marijuana smokers than tobacco smokers – Canadian study
Cannabis legalisation a ‘significant concern’ – American Heart Association
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