A new study from Gentofte University Hospital suggests that people who use medical marijuana for chronic pain might have a slightly higher risk of developing heart rhythm problems, also known as arrhythmias.
The study looked at data from 1.6 million people with chronic pain caused by conditions like cancer, arthritis, and neurological diseases. Among them, about 4,600 patients had received at least one prescription for medical marijuana.
The researchers found that those using medical marijuana were 64% more likely to experience a heart rhythm problem within six months compared to those who did not use the drug. However, the overall risk remained low. About 0.9% of medical marijuana users developed an arrhythmia, compared to 0.5% of non-users.
In Denmark, where the study was conducted, medical marijuana is available in three forms: oral CBD solutions and sprays, teas containing both THC and CBD, and dronabinol, a synthetic version of THC. The study found that patients using any of these forms had a higher chance of developing heart rhythm issues.
While the researchers could not determine whether marijuana was linked to specific types of arrhythmias, they noted that some are more dangerous than others. It is also unclear whether other factors, such as severe pain, played a role in the increased risk. People with severe pain are often prescribed opioids, which can also contribute to heart rhythm problems.
Scientists already know that chemicals in marijuana can affect the heart and blood vessels. The drug can change heart rate, raise or lower blood pressure, and influence blood clotting. These effects may explain why medical marijuana users in the study were more likely to develop arrhythmias.
The findings add to growing concerns about the possible risks of marijuana, whether used for medical or recreational purposes. While marijuana is often seen as a safe alternative to opioids for pain relief, this study suggests that its effects on the heart may need closer attention.
The study was led by Nina Nouhravesh and presented at a meeting of the European Society of Cardiology. More research is needed to understand the long-term impact of medical marijuana on heart health.
If you care about heart disease, please read studies about a big cause of heart failure, and common blood test could advance heart failure treatment.
For more information about heart health, please see recent studies about a new way to repair human heart, and results showing drinking coffee may help reduce heart failure risk.
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