Cannabis Smoking Is an Independent Risk Factor for Heart Attack, but Edibles May Not Be

After adjusting for tobacco use, cannabis smoking remained significantly associated with heart attack, with adjusted odds ratios from 1.03 to 5.24, particularly high in younger age groups. Among never-tobacco smokers, frequent cannabis smoking still increased MI risk (aOR=1.88). Non-smoked cannabis (primarily ingestion) was not associated with significant MI risk (aOR=1.00 for frequent use, aOR=1.31 ns for current use).

Systematic review following PRISMA guidelines, searching PubMed, Embase, and Google Scholar. 22 eligible studies identified examining cannabis use variations and myocardial infarction risk.

This is the first systematic review to distinguish between cannabis smoking and non-smoked cannabis for heart attack risk. The finding that the route of administration matters has major implications: the cardiac risk may be from combustion-related toxins (like carbon monoxide) rather than cannabinoids themselves.

The distinction between smoked and non-smoked cannabis for cardiac risk parallels the tobacco experience. If combustion is the key driver, harm reduction approaches (switching to edibles, vaping) could substantially reduce cannabis-related heart attack risk.

Relatively few studies examined non-smoked cannabis specifically, limiting those conclusions. Most non-smoked use was edibles; vaping data was sparse. Residual confounding from polysubstance use, lifestyle factors, and socioeconomic status cannot be fully excluded.