Regular Marijuana Use May Increase Risk of Heart Disease, Study Finds

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

A two-part observational study—presented at the annual meeting of the American College of Cardiology on March 5—found in the first part that people who used marijuana daily were about 34% more likely to develop CAD than people who have never used the drug. On the other hand, infrequent marijuana use was not correlated with higher odds for CAD.

“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,” Ishan Paranjpe, MD, the study’s lead author and resident physician at Stanford University, said in a news release. 

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

Paranjpe and his colleagues used data from the All of Us Research Program of the National Institutes of Health, which included health information and habits of 175,000 people, in addition to surveys about cannabis use frequency and medical records over 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.”

The Popularity of Marijuana Use in the United States

Over 50% of Americans live in states that have legalized marijuana for general medical use and there are over 20 states which have legalized marijuana for adult non-medical use, Rachel-Maria Brown Talaska, MD, director of inpatient cardiac services at Northwell Health told Health.

Data points on the topic are vast, ranging from ever-changing beliefs regarding marijuana’s legalization to the number of American adults who have tried the substance at some point. While these perspectives may ebb and flow, one thing holds fast—a higher percentage of Americans have tried marijuana than ever recorded previously.

“There have been rapid increases in marijuana use prevalence, in part due to changing social norms and attitudes about marijuana use, recent changes in the legal status of both medical and recreational marijuana use, and drug policy reform,” Dr. Talaska confirmed. 

As these changes continue to progress, younger generations continue to grow more comfortable and accustomed to marijuana use. Though it’s not strictly generational normalcy that explains the younger generation being the most likely to smoke regularly. Historically speaking, it has been found that individuals are most likely to smoke when they’re younger, and they will not carry on as they age.

“In young adults between the ages of 18 to 40, we’re seeing a higher amount of recreational use and also increased issues surrounding cardiovascular disease, such as stroke,” Robert Page, PharmD, MSPH, professor at the University of Colorado School of Pharmacy Medicine, explained to Health. 

“In the case of something like a stroke, that can seriously impact a young person’s life and they’re not thinking about those kinds of things,” he added. “So patients just need to be aware that this could be a potential risk factor for cardiovascular disease.” 

Marijuana Use and Cardiovascular Health?

Using marijuana can impact someone’s cardiovascular health because cannabinoids, a type of chemical found in marijuana can cause an increase in heart rate and affect the sympathetic nervous system, noted Dr. Page. 

He explained that when you increase your heart rate, it also means you’re increasing myocardial oxygen demand, which means that the heart is going to need more oxygen to pump more efficiently. 

“The heart is going to have to work harder and therefore you get what we call tachycardia, or an increased risk for heart rate which can predispose you to potential arrhythmias, angina, and chest pain,” he continued. 

Dr. Page went on to explain that when the sympathetic nervous system becomes excessively activated it can lead to prolonged stress and increase overall heart rate and workload. This in the long term may play a role in developing chronic obstructive pulmonary diseases (COPD), such as emphysema and chronic bronchitis, and other heart conditions like myocardial infarction, or heart attack.

“By stimulating the sympathetic nervous system, we are activating all of these compensatory mechanisms that can lead over the long term to cardiovascular disease,” he said. 

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.

Does the Method of Marijuana Consumption Matter?

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.”

Alternative Methods to Marijuana Use for Anxiety

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:

• Staying active
• Limiting caffeine intake
• Prioritizing healthy sleep habits 
• Practicing meditation, mindfulness, or deep breathing exercises
• Performing relaxing activities such as yoga or Tai Chi 
• Reducing toxic exposures, such as excessive alcohol consumption
• Reducing screen time and social media exposure
• Seeking professional counseling or treatment when necessary 

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.”