A systematic review and meta-analysis utilizing real-world data reveal positive associations between cannabis use and major adverse cardiovascular events (MACEs). These findings, which were published in Heart, are intended to enhance the general awareness of cannabis’s potential to cause cardiovascular harm, particularly in those who present or are at risk for serious cardiovascular disorders.¹

Legalizing cannabis and expanding its medicinal use worldwide have likely contributed to significant changes in the general population’s perception of the drug, wrote the authors, as well as the overall rise in consumption and use. As this has increased over the past decade, concerns regarding users who initiated cannabis outside of regulated medical uses have increased. Particularly, there are concerns regarding cardiovascular risks or disorders.¹

For these reasons, the investigators conducted a study to evaluate the risk of MACEs related to cannabis use. This was assessed by analyzing real-world pharmacoepidemiological data and conducting a systematic review and meta-analysis to further quantify this risk.¹

Scientific evidence between January 1, 2016, and January 31, 2023, was included in the study. These studies were original pharmacoepidemiological research that provided risk estimates on cannabis-related MACEs—such as cardiovascular death and nonfatal acute coronary syndrome (including myocardial infarction [MI] or nonfatal stroke)—and were accumulated from PubMed, Web of Science, and Scopus. The studies’ design, duration, baseline characteristics, exposure, inclusion criteria, sample size, effect size, and confounding factors—including exposure to psychoactive substances—were extracted.¹

A total of 24 articles were included from an initial 3012 records. Of these, 17 were cross-sectional studies, 6 were cohort studies, and 1 was a case-control study. There were 432,245,972 patients aged 19 to 59 years (average: 38.4 years) across the included studies. Notably, cannabis users were primarily males (54% to 100%) in studies for which this data was available (n = 14), and users tended to be younger than nonusers.¹

“This is one of the largest studies to date on the connection between marijuana and heart disease, and it raises serious questions about the assumption that cannabis imposes little cardiovascular risk,” Lynn Silver, MD, MPH, FAAP, clinical professor of epidemiology and biostatistics at the University of California San Francisco, pediatrician, and senior advisor at the Public Health Institute, explained in a CNN Health article.

Exposure corresponded to the use of cannabis in all studies, with 1 specifically focused on medical cannabis. The estimated risk ratio (RR) was about 1.29 (95% CI, 1.05–1.59) for acute coronary syndrome (ACS), 1.20 (95% CI, 1.13–1.26) for stroke, and 2.10 (95% CI, 1.29–3.42) for cardiovascular death. As measured in 2 studies, there was no statistically significant association found for the composite outcome combining ACS and stroke. Of note, the focused analysis restricted to cohort studies generated comparable results to the primary model (RR = 1.32 [95% CI, 1.01–1.73]).¹

Cannabis use was also observed to significantly increase all-cause mortality and cardiovascular mortality in a cohort of patients who were diagnosed with MI before the age of 50 following adjustment for age, cardiovascular risk factors (eg, tobacco smoking), and comorbidities. The authors noted that these data are consistent with results from studies included in a previous review in which cannabis was statistically associated with increased middle-term—but not long-term—mortality in patients with a history of acute MI. Additionally, these were further supported by a more recent study that demonstrated a significant association between cannabis use and death from cardiovascular causes (HR = 2.29 [95% CI, 1.10–4.78]). There was no significant association found for all-cause mortality (HR = 1.14 [95% CI, 0.81–1.59]).¹

“Getting this right is critically important because cardiovascular disease is the top cause of death both in the United States and globally. Clinicians need to screen people for cannabis use and educate them about its harms, the same way we do for tobacco, because in some population groups it’s being used more widely than tobacco,” Silver said. “Our regulatory system, which has been almost entirely focused on creating legal infrastructure and licensing legal, for-profit [cannabis] businesses, needs to focus much more strongly on health warnings that educate people about the real risks.”²

REFERENCES

1. Storck W, Elbaz M, Vindis C, Déguilhem A, Lapeyre-Mestre M, Jouanjus E. Cardiovascular risk associated with the use of cannabis and cannabinoids: a systematic review and meta-analysis. Heart. 2025;0:1–10. doi:10.1136/heartjnl-2024-325429.

2. LaMotte S. Marijuana use dramatically increases risk of dying from heart attacks and stroke, large study finds. CNN Health. Updated June 18, 2025. Accessed June 18, 2025. https://www.cnn.com/2025/06/17/health/marijuana-heart-death-wellness