Oregon Adults' Cannabis and Alcohol Use: Associations With Local Cannabis Retail Access, 2014-2022.

INTRODUCTION: A state representative sample was used to test the associations between local access to cannabis retailers and Oregon adults' cannabis and alcohol use outcomes as well as differential associations by age group. METHODS: Respondents' 30-day cannabis use (1+ days) and frequent use (10+ days) and 30-day binge drinking and heavy alcohol use were drawn from Behavioral Risk Factor Surveillance System surveys (2014-2022) and matched with a geospatial density measure of local cannabis retail access by respondent ZIP code. Models adjusted for time trends. Analyses were run in 2023-2024. RESULTS: Oregon adults in the lowest (AOR=1.31; 95% CI=1.12, 1.53), middle (AOR=1.47; 95% CI=1.25, 1.73), and highest (AOR=1.59; 95% CI=1.36, 1.86) thirds of local retail access had higher odds of 30-day cannabis use than those in the pre-market period. Odds of frequent cannabis use also increased with greater retail access. Associations between retail access and cannabis use were significant in every adult age group except minors aged 18-20 years. Odds of heavy alcohol use were lower with greater cannabis retail access, primarily among those aged 21-24 years and ≥65 years. CONCLUSIONS: Research on the mechanisms through which retail density and proximity effects occur for younger- to middle-aged adults would inform state and local policies aimed at preventing cannabis misuse. For older (those aged ≥65 years) adults, the net public health impacts of retail access-related increases in cannabis use are less clear given the associated decreases in their heavy alcohol use.