Daily cannabis use found to increase heart disease risk by 34%

As more and more states in the U.S. decriminalize non-medical marijuana use, the pros and cons of this popular drug are being researched extensively. While positive effects such as high efficacy in treatment-resistant epilepsy, improved insomnia from depression and anxiety, and reduced symptoms of OCD have been found, the harmful effects of marijuana outweigh its benefits.

Cannabis contains heavy metals, which can lead to physical, muscular, and nervous system degeneration, mimicking diseases such as Alzheimer's disease, Parkinson's disease, etc., according to one study. High-potency strains have been found to raise the incidence of psychotic disorders.

A recent Stanford University study adds to the debate on the drug's risks and benefits. Frequent marijuana use has been linked with a 34 percent increase in the risk of developing coronary artery disease (CAD) compared to individuals who have never used the drug, according to the press release.

CAD is a heart condition caused by the narrowing or blockage of blood vessels that supply the heart. In severe cases, it can lead to heart failure or a heart attack which is the third leading cause of mortality worldwide.

A data-driven approach

Researchers used self-reported data from a diverse U.S. health database to relate marijuana usage with CAD diagnosis rates. The team first made meticulous adjustments for age, sex, and other cardiovascular disease risk factors and then applied mendelian randomization — a statistical technique that uses genetic markers to investigate causal relationships between a risk factor and a disease outcome.

The team investigated genetic markers that cause cannabis use disorder (CUD) — a psychiatric condition leading to cannabis dependency — and CAD. The relationship between CUD and CAD is dose-response type meaning more frequent cannabis use is associated with a higher risk of CAD.

Physiological explanations

Cannabis use may increase heart rate and blood pressure, putting additional strain on the heart and blood vessels, resulting in plaque buildup on arteries' walls, per a UCLA study. Cannabis use may lead to chronic inflammation throughout the body, a known risk factor for the development of CAD.

Additionally, an in vivo study found that cannabis caused inflammation in cells that line the blood vessels leading to an increased risk for heart attacks. Hence, the harmful effects of marijuana on the cardiovascular system are undeniable.

With the increased legalization of marijuana, a rise in heart attacks may be observed, and previously unknown harms of cannabis may come to light. Therefore, cannabis users must be honest with their doctors regarding their drug intake to aid in better treatment.

The study will be presented at ACC.23 in New Orleans.