Cannabis use has been found to significantly increase the risk of dying from cardiovascular disease, according to a newly published meta-analysis in the journal Heart. The study reports that individuals who use cannabis face a doubling in the risk of fatal cardiovascular events. Additionally, cannabis use is associated with a 29% greater risk of acute coronary syndrome—defined as sudden, reduced blood flow to the heart—and a 20% higher risk of experiencing a stroke. These findings come from an extensive analysis of real-world data and provide fresh insights into the potential dangers of cannabis use, particularly in the context of shifting public attitudes and increased legalisation.
The editorial accompanying the study argues that cannabis should be treated in regulatory frameworks much like tobacco: not criminalised, but actively discouraged. In a linked editorial, Emeritus Professor Stanton Glantz and Dr Lynn Silver call for robust public health interventions to limit secondhand exposure and improve awareness of the drug’s cardiovascular effects. As cannabis use has become more widespread—driven in part by legalisation and the expansion of medical cannabis programmes—many people now perceive it as harmless or even health-promoting. This shift in perception, the editorial warns, is not grounded in scientific evidence and could be placing millions at unnecessary risk.
In response to these trends, researchers conducted a systematic review of studies published between January 2016 and December 2023, focusing on cannabis use and serious cardiovascular outcomes, including death from cardiovascular disease, heart attack, and stroke. From a pool of over 3,000 articles, 24 studies met the inclusion criteria for the pooled data analysis. These encompassed a range of designs, including cross-sectional, cohort, and case-control studies, and represented a combined population of roughly 200 million individuals. Most participants were aged 19 to 59, with cannabis users skewing younger and more likely to be male compared to non-users.
The results confirmed a substantial association between cannabis use and cardiovascular harm. Specifically, the data showed a 29% higher risk of acute coronary events, such as heart attacks, and a 20% increase in the likelihood of stroke among cannabis users. Perhaps most concerning was the twofold increase in the risk of cardiovascular death. While the precise causal mechanisms remain unclear, the findings challenge the notion that cannabis is a benign recreational or medicinal substance. They suggest instead that the drug carries serious health consequences that may parallel those of tobacco, particularly when used regularly or in high-potency forms.
However, the researchers acknowledge that the included studies had limitations. Many exhibited moderate to high risk of bias due to missing data, inconsistent definitions of cannabis exposure, and reliance on self-reporting. Furthermore, because most of the studies were observational, they cannot definitively establish a cause-and-effect relationship. Some of the research also reused datasets, which may limit the breadth of applicability. Nonetheless, the authors argue that their meta-analysis is the most thorough examination to date of the connection between cannabis and cardiovascular risk, drawing on an unprecedented scale of population-level evidence.
The editorial further emphasises the need to investigate how different forms of cannabis impact cardiovascular health. The cannabis landscape has evolved considerably in recent years, with new high-potency concentrates, synthetic cannabinoids, and edible products becoming increasingly common. Whether the observed cardiovascular risks stem from cannabinoids themselves, inhaled particulates, or other compounds, such as terpenes, remains uncertain. Understanding these nuances is critical to crafting effective public health messages and regulatory policies that can mitigate risk across the broad spectrum of cannabis products now available.
Ultimately, the authors conclude that cardiovascular disease prevention must become a central component of cannabis regulation. They call for the implementation of mandatory warning labels, public education campaigns, and policies that limit exposure to cannabis vapour in public spaces. They argue that current regulatory efforts have focused too narrowly on establishing legal markets, often at the expense of public health and well-being. As evidence of cannabis-related harm continues to mount, regulatory frameworks must evolve to prioritise health and safety, adopting measures similar to those used successfully in tobacco control to protect both users and the general public.
More information: Wilhelm Storck et al, Cardiovascular risk associated with the use of cannabis and cannabinoids: a systematic review and meta-analysis, Heart. DOI: 10.1136/heartjnl-2024-325429
Journal information: Heart Provided by BMJ Group
