When cannabis sales start, cardiac admissions rise faster

Clinical takeaway: Consider asking patients with cardiac disease, particularly those with heart failure, about cannabis use given the potential risks. 

Clinicians field the cannabis question more often as use climbs among older adults, the patients already at higher risk for cardiovascular events. The evidence they have at hand often conflicts: some studies tie cannabis to arrhythmia, myocardial infarction (MI), and stroke, while others find no link. People who use cannabis for pain or anxiety may also carry cardiovascular risk for other reasons. 

Legalization offers a different angle on the question. This analysis of hospital discharges extends the evidence from individual users to the population level. It tests whether admissions for specific cardiac conditions changed as legal sales began. 

Admissions for heart failure climbed 3.7% faster for each year of legal cannabis sales than in regions without sales, the largest increase of the cardiac diagnoses studied. MI admissions grew 3.1% and atrial fibrillation admissions 2.3%, each beyond the trend in comparison regions. 

Stroke, venous thromboembolism, and ventricular tachycardia also trended upward, but the increases did not reach statistical significance. The analysis may have lacked the power to detect changes in less frequent cardiovascular diagnoses, such as ventricular tachycardia and venous thromboembolism. 

Cannabis-related hospital admissions rose 13.8% a year. Admissions for urinary stones and opioid-related diagnoses held steady. 

The analysis drew on more than 50 million hospital discharges from the National Inpatient Sample, 2012 to 2018, using a difference-in-differences design. It compared the Western census region, where recreational sales began in 2014, with the other regions. The whole Western region counts as exposed from 2014, though states began sales in different years. Cannabis-related admissions were the positive control, and urinary stones and opioid-related admissions the negative controls. 

Cannabis sales data might show whether edible and inhaled products differ in cardiovascular outcomes, and states yet to legalize might coordinate the timing of sales to study the effects. 

“While an observational study cannot prove causality, our findings point to potential adverse effects of recreation legalization on population health,” the authors caution. “Globally, our findings support a cautious approach to legalization laws accompanied by data collection on [cardiovascular] outcomes.” 

Source: Slavin SD, et al. (2026 Oct 22) BMJ Open. Cannabis legalisation and cardiovascular hospitalisations in the United States: nationwide difference-in-differences analysis, 2012–2018