Association between consistent marijuana use among young adults and the risk of developing coronary artery diseases: a meta-analysis

Abstract Introduction In 2023 cannabis use among Europeans aged 15 to 34 was estimated at 15% (15.1 million), with males being approximately twice as likely to report use as females. Recent studies estimate that approximately 3 in 10 cannabis users develop cannabis use disorder. Despite its widespread use, research on both the long-term and short-term cardiovascular effects of marijuana remains inconclusive, due to conflicting evidence and methodological limitations in prior studies. To address this gap, we conducted a systematic review and meta-analysis to evaluate the association between marijuana use and the 10-year-ASCVD risk score and the incidence of coronary artery disease. Purpose This study aimed to perform a systematic review and meta-analysis to investigate the association between marijuana smoking and the incidence of coronary artery disease (CAD) and the 10-year atherosclerotic cardiovascular disease (ASCVD) risk score. Methods PubMed and Cochrane databases were searched for observational studies that compared the cardiovascular effects of marijuana use between users and non-users of the drug. As defined in the studies included, we considered marijuana users to be people who smoked cannabis at least 4 times per month in the past year, continuously, with varying intensity, excluding occasional and past 30-day abstinent users. This threshold was chosen to ensure a meaningful assessment of chronic exposure while avoiding confounding from sporadic use. Primary outcomes of interest consisted of coronary artery disease (CAD), which included acute myocardial infarction and acute coronary syndrome, and 10-year ASCVD risk score. Results A total of seven observational studies were included, encompassing 61,906,153 patients, of whom 721,565 were marijuana users. The study population ranged in age from 18 to 59 years, with a mean age of approximately 37 years. Marijuana users were predominantly male (47.8%) and had a 20.6% higher likelihood of also being tobacco smokers. The incidence of coronary artery disease (odds ratio OR 1.64 CI 1.60 to 1.75, p 0.00001) in the marijuana users population was significantly higher than in the marijuana non-users population. However, the 10-year ASCVD risk score (std. mean difference SMD -0.84 CI -0.85 to -0.82, p 0.00001) indicates that marijuana users do not have an increased risk of developing atherosclerotic cardiovascular disease over a 10-year period. Conclusion The incidence of coronary artery disease was significantly higher among marijuana users. Nevertheless, the 10-year ASCVD risk score suggests that marijuana use does not correlate with an increased long-term risk of developing cardiovascular disease. This discrepancy may indicate a greater likelihood of early-onset heart disease or imply that traditional risk scores fail to capture the increased risk observed in epidemiological studies, potentially underestimating the true cardiovascular impact of marijuana use.10-year-ASCVD risk score Incidence of coronary heart disease