Medical Cannabis for Chronic Pain: How Does It Affect the Heart?

A Danish study examined the effect of medical cannabis on cardiovascular health when used as a treatment for chronic pain (1). The study, “Cannabis for chronic pain: cardiovascular safety in a nationwide Danish study,” was published in the European Heart Journal in January 2024 and is reportedly the first of its kind (1,2). As the impetus for the investigation, the authors cited the need for more research into the safety of prescribed cannabis as more countries are seeing physicians recommend medical cannabis to their patients and as more connections are being made between recreational cannabis use and cardiovascular side effects (1).

For this study, the researchers used patient data from Danish national registers, comparing those who used cannabis (5391 total) for their chronic pain and those who did not (26,941) (1). Researchers specifically examined first-time arrythmia and acute coronary syndrome risks (1).

“In patients with chronic pain, the use of prescribed medical cannabis was associated with an elevated risk of new-onset arrhythmia compared with no use—most pronounced in the 180 days following the initiation of treatment,” the authors stated in the abstract (1). The increased risk—0.8%—was more than twice the risk for patients who did not use cannabis, though the differences in risk grew smaller after one year of treatment (2). The study did not find a significant association between acute coronary syndrome and medical cannabis use (1).

Anders Holt, the lead investigator for the study, explained that more studies are needed in this area, especially for long-term cannabis use (2). "I don't think this research should make patients with chronic pain refrain from trying medical cannabis if other treatment has been inadequate,” he stated (2). "However, these results do suggest some improved monitoring may be advisable initially, especially in patients who are already at increased risk of cardiovascular disease."

Read more recent studies on cannabis use and cardiovascular risks and cannabis use disorder and cardiovascular disease.

References

1. Holt, A.; Nouhravesh, N.; Strange, J. E.; Kinnberg Nielsen, S.; Schjerning, A.-M.; Vibe Rasmussen, P.; Torp-Pedersen, C.; Gislason, G. H.; Schou, M.; McGettigan, P.; et al. Cannabis for chronic pain: Cardiovascular Safety in a nationwide Danish study. European Heart Journal 2024 DOI: 10.1093/eurheartj/ehad834.
2. European Society of Cardiology. Research suggests link between medical cannabis for chronic pain and abnormal heart rhythm https://medicalxpress.com/news/2024-01-link-medical-cannabis-chronic-pain.html (accessed Jan 16, 2024).