Stroke phenotype in cannabis users among young adults with ischemic stroke

Background and purpose Incidence of ischemic stroke in young adults has been steadily increasing over the past 20 years. One hypothesis to explain this phenomenon is the increase in the use of illicit drugs, including cannabis. However, the mechanisms and the clinical presentation of ischemic stroke associated with cannabis use are unclear. The objective of this study was to describe the phenotype of ischemic stroke in cannabis users compared to nonusers among a population of young adults with a first‐ever ischemic stroke. Methods Patients aged 18–54 years consecutively hospitalized in a university department of neurology for a first‐ever ischemic stroke from January 2017 to July 2021 were included. Drug use over the past year was assessed by a semistructured interview, and the stroke phenotype was described using the ASCOD classification. Results A total of 691 patients, including 78 of 691 (11.3%) cannabis users, were included. Cannabis use was independently associated with potential A1 (odds ratio [OR] = 3.30, 95% confidence interval [CI] = 1.45–7.5, p = 0.004) and uncertain A2 (OR = 13.1, 95% CI = 2.89–59.4, p < 0.001) atherosclerotic cause of stroke after adjustment for vascular risk factors including tobacco and other drug use. Moreover, the association of atherosclerosis and cannabis use was significant for frequent (OR = 3.13, 95% CI = 1.07–8.6, p = 0.030) and daily cannabis use (OR = 4.43, 95% CI = 1.40–13.4, p = 0.008), but not for occasional use. Conclusions We found a significant, independent, and graded association of cannabis use with the atherosclerotic stroke phenotype.