Study Finds Regular Cannabis Consumption May Heighten Heart Disease Vulnerability

New research suggests that frequent cannabis use may pose a risk factor for coronary artery disease (CAD).

At the annual meeting of the American College of Cardiology on March 5, researchers presented a two-part observational study. The first part found that people who used marijuana daily had a 34% higher probability of developing CAD compared to those who had never utilized the drug. However, infrequent marijuana use did not seem to increase CAD risk.

Lead author and resident physician at Stanford University, Ishan Paranjpe, MD, stated 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.”

In the second part of the study, the researchers identified a causal relationship between cannabis use disorder and CAD risk using a genetics-based approach called “Mendelian randomization”. They found that individuals with a genetic susceptibility to cannabis use disorder or severe cannabis dependence had an increased risk of developing CAD compared to other participants.

The researchers collected data from the All of Us Research Program of the National Institutes of Health, which included health information and habits of 175,000 individuals. The study also incorporated surveys about cannabis use frequency and medical records spanning several years.

“In terms of the public health message, it shows that there are probably certain harms of cannabis use that weren’t recognized before,” Dr. Paranjpe concluded. “People should take that into account.”

More than 50% of Americans live in states that have legalized marijuana for general medical or non-medical use. As the legality of marijuana continues to change, younger generations are growing increasingly accustomed to cannabis use. However, individuals who use marijuana can be at risk for cardiovascular issues such as stroke or arrhythmias, warned Robert Page, PharmD, MSPH, professor at the University of Colorado School of Pharmacy Medicine. Cannabinoids, the chemicals found in marijuana, can increase heart rate and affect the sympathetic nervous system, which can have detrimental effects on one's cardiovascular health.

Using marijuana can also increase a person’s risk of heart disease because it can activate certain proteins that can lead to cell death, a decrease in heart pumping function, and activation of the systemic inflammatory response system, which can trigger blood vessel dysfunction, Dr. Talaska added.

There are different ways for people to consume marijuana, such as smoking via pipes, joints, blunts and bongs, vaping, or eating edibles, gummies, and other baked goods, Yu-Ming Ni, MD, a cardiologist specializing in noninvasive cardiology at MemorialCare Heart and Vascular Institute at Orange Coast Medical Center in Fountain Valley, CA, told Health. 

While more research is needed to examine the health implications of various forms of marijuana consumption on the heart, brain, and other vital organs, Dr. Ni noted that smoking marijuana can be more harmful to lung health compared to other means. 

“Smoking increases inhaled toxins. It doesn’t matter if it’s cigarettes or marijuana—you’re consuming those toxins and they’re getting into the airways, getting into blood vessels, and damaging [those] blood vessels,” he said.

Dr. Ni added that most people who smoke marijuana also tend to inhale more deeply with each breath, and tend to pull in more toxins and irritants into several parts of the lungs compared to cigarette smokers.

No matter how you may be consuming marijuana, Dr. Page believes all methods to some point can potentially pose health risks. 

“Based on observational data that looked at smoking, vaping, or edibles, the bottom line is the risk for myocardial infarction appeared to be the same across the board,” he said. “The new data validates other observational data—that is, the longer you are using, we do know there is an association of having a much higher risk than those who are using it intermittently.”

All this to say, experts understand that there are individuals who may be using marijuana to alleviate anxiety and stress or as a way to calm down. While medical guidance is direct and foremost recommended, experts recommend additional methods of anxiety relief including:

Dr. Page noted that when trying new alternatives, it can take some time before you feel calm or relaxed. But he encourages people to try things that work best for them and really evaluate their marijuana use. 

“Just remember, just because it’s natural doesn’t mean it’s safe. It’s just like any other drug, it has drug interactions and it’s going to have side effects,” Dr. Page concluded. “One of those side effects could be myocardial infarction. They need to make an informed decision and weigh the risk-benefit.”