Association of Local Cannabis Policy and Retail Availability With Cannabis Use and Problematic Cannabis Use Among Adolescents in Northern California

Objectives. To examine whether local cannabis policies and retail availability are associated with cannabis use and problematic cannabis use (PCU) among adolescents in Northern California. Methods. The sample comprised adolescents aged 13 to 17 years screened for past-year cannabis use during well-child visits in 2021. Exposures included local bans on cannabis storefront retailers, policy protectiveness, and retail proximity and density. Outcomes included self-reported past-year cannabis use and PCU diagnoses. Modified Poisson regression models adjusted for sociodemographics. Results. The sample (n = 103 134) was 51.1% male with a median age of 15 years (interquartile range [IQR] = 14-16 years); 5.5% self-reported cannabis use, and 0.3% had diagnosed PCU. Adolescents had a lower prevalence of cannabis use in jurisdictions that banned storefront retailers (adjusted prevalence rate [APR] = 0.857; 95% confidence interval [CI] = 0.814, 0.903 vs allowed), banned delivery (APR = 0.751; 95% CI = 0.710, 0.795 vs allowed), or had more policy protections (APR range = 0.705-0.800). Lower PCU prevalence was also found among those in jurisdictions that banned (vs allowed) storefront retailers (APR = 0.786; 95% CI = 0.629, 0.983) or delivery (APR = 0.783; 95% CI = 0.616, 0.996). Longer drive time and lower density of storefront retailers were associated with a lower cannabis use prevalence. Conclusions. More protective cannabis policies and less retail availability were associated with a lower prevalence of adolescent cannabis use and PCU.