Effects of Legalizing Recreational Cannabis Sales on Cannabis Use and Cannabis-Related Disorder Among Presentations...

Limited research exists on the impact of changing cannabis policies on psychiatric populations, who are especially vulnerable to the negative effects of substance use. This study examined the changes in cannabis use and cannabis-related disorders across age groups of psychiatric emergency presentations after the start of recreational cannabis sales in Massachusetts.

Cross-sectional electronic health records from 7,350 unique presentations to a psychiatric emergency service in a tertiary care hospital in Massachusetts were analyzed. Logistic regressions estimated changes in the rates of urine tetrahydrocannabinol positivity and cannabis-related disorder ICD-10 diagnosis codes (F12.X) from precommercialization (January 1, 2017-November 19, 2018) to postcommercialization (November 20, 2018-December 31, 2019) periods across different age groups (12-17, 18-25, 26-49, 50-70 years), controlling for biological sex, race, and ethnicity.

The rates of tetrahydrocannabinol positivity increased significantly from pre to postcommercialization periods (32.4%-36.3%, p<0.001) but not the rates of cannabis-related disorder (10.5%-11.7%). Adolescents (aged 12-17 years) had the largest increase in tetrahydrocannabinol positivity (5%-17.3%, AOR=4.32 [2.15, 8.68]), whereas adults (aged 26-49 years) experienced a modest increase (37.7%-42.5%, AOR=1.24 [1.08, 1.42]). Only the adolescent group had a significant increase in cannabis-related disorders (3.2%-12.1%, AOR=4.63 [1.97, 10.87]).

Commercialization of recreational cannabis sales may disproportionately affect adolescents with psychiatric illnesses or vulnerabilities, resulting in an increased need for psychiatric emergency care. Further research is needed to examine the impact of cannabis policies on this population to inform targeted prevention efforts.