Medical Marijuana Use Linked To 74% Increased Risk Of Heart Rhythm Disorders In A Hospital Study: What Does This Really Mean?

This article was originally published in Agust 2022.

New research presented at ESC Congress 2022 revealed a correlation between medical marijuana use and heart rhythm disorders.

Researchers from Gentofte University Hospital, Denmark examined data from almost 5,000 patients who used medical cannabis to treat chronic pain. What they discovered, as the European Society of Cardiology reported, is that “medical cannabis users have a 74% higher risk of heart rhythm disorders compared with non-users,” study author Dr. Nina Nouhravesh said.

Before you put out the joint in your hand, wait for the study details and remember that correlation doesn’t necessarily mean causation.

Study Highlights

 “Chronic pain is a rising problem,” Nouhravesh said. “According to Danish health authorities, 29% of Danish adults over 16 years of age reported chronic pain in 2017, up from 19% in 2000. Medical cannabis was approved in January 2018 on a trial basis in Denmark, meaning that physicians can prescribe it for chronic pain if all other measures, including opioids, have proven insufficient. Safety data are sparse, hence this study investigated the cardiovascular side effects of medical cannabis, and arrhythmias in particular, since heart rhythm disorders have previously been found in users of recreational cannabis.”

Those 4931 patients who took part in the study claimed at least one prescription of marijuana – dronabinol 29%, cannabinoids 46%, and cannabidiol 25. Each user was matched by age, gender and pain diagnosis to five non-users with chronic pain as a control group. Both users and controls were followed for six months and their risks of new cardiovascular conditions were examined and compared.

The median age of participants was 60 years, and there were more women than men. Among conditions participants had were cancer (17.8%), arthritis (17.1%), back pain (14.9%), neurological disorders (9.8%), headaches (4.4%), complicated fractures (3.0%) and 33.1% other diagnoses.

The study determined the absolute risk of new-onset arrhythmia was 0.86% in medical marijuana users, which compares to 0.49% in non-users, for a relative risk of 1.74. Furthermore, it was concluded that medical cannabis users have no higher risk for new-onset acute coronary syndrome and heart failure.

While the study, confirmed a 74% higher risk of heart rhythm disorders, “the absolute risk difference was modest,” Nouhravesh said. “It should be noted that a higher proportion of those in the cannabis group were taking other pain medications, namely non-steroidal anti-inflammatory drugs (NSAIDs), opioids and anti-epileptics, and we cannot rule out that this might explain the greater likelihood of arrhythmias.”

Other Studies On Cannabis & Heart Conditions

Even though the new research shows that those who use medical marijuana for chronic pain have a higher risk of arrhythmia, as the study author pointed out, the cause might not be cannabis, but other pain medication.

Nevertheless, other studies point out to relation between marijuana and heart disease.

One of the latest studies, led by researchers at Stanford Medicine revealed that individuals who consume marijuana have a higher risk of heart disease and heart attack.

According to the study, THC or the psychoactive component of marijuana causes inflammation in endothelial cells that line the interior of blood vessels, reported Stanford Medicine. Furthermore, the compound known to stimulate the often yearned for sensation of being high can lead to atherosclerosis or the buildup of fats in artery walls in laboratory mice.

The study further determined that frequent cannabis consumers are more likely than nonusers to have their first heart attack before the age of 50 - or what is called a premature heart attack, which carries a risk of subsequent heart attack or heart failure. 

Another study by the Canadian Medical Association Journal from September revealed something similar - adults under 45 who used cannabis in the 30 days before the research suffered nearly twice as many heart attacks as those who did not use marijuana.

Conclusions

It is only safe to say that cannabis, which is a plant comprised of many compounds that differently impact our bodies and minds, is still vastly underresearched. Therefore, studies like this new one that indicates there’s a connection are also of importance as they can point researchers in the right direction in terms of studying marijuana and its impacts.

Photo: Courtesy of Robina Weermeijer via Unsplash