Associations of Local Cannabis Policy and Retail Availability in Northern California with Adverse Adolescent Mental Health Outcomes.

BACKGROUND

Local policies prohibiting cannabis sales and lower cannabis retail availability are associated with a lower prevalence of adolescent cannabis use. In this study, we examined whether local prohibitions on cannabis retail and cannabis retailer proximity and density are associated with adverse cannabis-related mental health outcomes among adolescents.

METHODS

Cross-sectional study of 95,645 Northern California adolescents aged 13-17 who completed a well-check questionnaire in 2021 during standard pediatric care. Exposures included local bans on cannabis storefront and delivery retailers, and retail proximity and density in relation to adolescents' geocoded residences. Past-year psychotic, depressive, and anxiety disorders were identified using ICD codes; self-reported depression symptoms came from the questionnaire.

RESULTS

Relative to adolescents in jurisdictions allowing storefront and delivery retail, those in jurisdictions prohibiting storefront retail only (aPR = 0.52; 95%CI: 0.32-0.85), or prohibiting both (aPR = 0.67; 95%CI: 0.48-0.92) had a lower prevalence of psychotic disorders. Greater retailer density (≥6 vs. 0 retailers within a 15-min drive) was associated with a greater prevalence of anxiety disorders (aPR = 1.11; 95%CI: 1.04-1.19), depressive disorders (aPR = 1.10; 95%CI: 1.02-1.19) and depression symptoms (aPR = 1.08; 95%CI: 1.01-1.15). Having a ≥20-min (vs. <5-min) drive to the nearest retailer was associated with a lower prevalence of psychotic (aPR = 0.53; 95%CI: 0.33-0.86), anxiety (aPR = 0.89; 95%CI: 0.82-0.97), and depressive disorders (aPR = 0.89; 95%CI: 0.81-0.98) and depression symptoms (aPR = 0.91; 95%CI: 0.84-0.99).

CONCLUSIONS

Local policies prohibiting storefront retail were associated with a lower prevalence of psychotic disorders. Greater retail availability of cannabis near adolescents' residences was associated with a greater prevalence of psychotic, anxiety, and depressive disorders, and depression symptoms. Policies limiting retail density and availability may help reduce cannabis-related harms and merit further assessment.