The prevalence of cannabis use disorder in attention-deficit hyperactivity disorder: A clinical epidemiological meta-analysis

Studies have shown that individuals with attention-deficit hyperactivity disorder (ADHD) pose an increased risk for developing substance use disorders. Increased cannabis product accessibility and recent legislative changes have led to increased cannabis consumption, thereby increasing the risk of cannabis use disorder (CUD). The present meta-analysis explored the lifetime and current prevalence of CUD in ADHD. A systematic review was conducted using the following databases: PubMed, PsycINFO and Web of Science. A total of 14 articles were included and used to estimate the aggregate lifetime and current prevalence of CUD in ADHD alongside risk ratios comparing increased risk of CUD in ADHD versus control samples. Mixed and random-effects models indicated that lifetime and current prevalence rates of CUD in ADHD populations were 26.9% and 19.2%, respectively (although prediction intervals ranged from 12.4% to 48.8% and 5.5%–39.1%, respectively). Analysis of the risk ratios indicated that those with ADHD were at 2.85- and 2.91-times greater risk of a lifetime or current diagnosis of CUD, respectively, than those in the general population. Our findings support the need for additional research on the prevalence of CUD in those with ADHD, as well as the inclusion of CUD screening in the treatment of ADHD.