Associations Between State Cannabis and Alcohol Policy Restrictiveness and College Students' Cannabis Use, Binge...

U.S. college students' cannabis use and binge drinking occur in the context of state-level substance policies. The Cannabis Policy Scale (CPS), a continuous measure of state policy restrictiveness, may offer greater nuance than policy categories such as recreational cannabis legalization for examining associations with substance use.

College students (n = 49,211) aged 18-30 years participating in the 2018-2019 Healthy Minds Study reported past-month cannabis use, past 2-week binge drinking, and co-use. Associations of state-level CPS and Alcohol Policy Scale (APS) scores with each outcome were tested in logistic regressions, adjusting for individual- and institution-level covariates and accounting for nesting of students in institutions.

Higher CPS scores (more restrictive state cannabis policies) were associated with lower odds of student-level cannabis use (OR = 0.90; 95% CI = 0.87, 0.93; p < 0.001) and co-use (OR = 0.92; 95% CI = 0.89, 0.95; p < 0.001). APS scores were positively associated with odds of cannabis use within non-legal states. Students in recreational states used more cannabis, yet unexpectedly, within recreational states, CPS was associated with higher odds of cannabis use.

College students' substance use was sensitive to state cannabis policies after accounting for state alcohol policies. In states with less restrictive cannabis policies, cannabis use and co-use were more common, suggesting complementarity. Within non-legal states, more restrictive alcohol policies were linked to higher cannabis use odds, suggesting substitution. State CPS and APS scores may inform policymakers' efforts to reduce college students' substance use. Future studies should replicate findings in contemporary cohorts, explore social justice implications, and consider concurrent campus and community policies.