Lower-Risk Cannabis Use Guidelines: Adherence in Canada and the U.S.

Abstract

This study examines the prevalence of risky cannabis use based on adherence to the Lower-Risk Cannabis Use Guidelines. Respondents aged 16-65 years in Canada and the U.S. (N=27,024) completed the online 2018 International Cannabis Policy Study. Participants completed measures corresponding to the Lower-Risk Cannabis Use Guidelines and Alcohol, Smoking and Substance Involvement Screening Test. Analyses were conducted in 2019. More than half of the respondents (57.3%, n=15,489) had ever used cannabis, and 28.1% (n=7,584) had used it in the past 12 months (current use). The majority of current consumers (88.8%) reported nonadherence to ≥1 guideline other than ever use. These behaviors included smoking ≥50% of all cannabis consumed (69.8%), using high-tetrahydrocannabinol products (44.9%), initiating cannabis use before age 16 years (35.9%), daily/near-daily use (32.2%), driving after cannabis use (26.1%), cannabis use during pregnancy or with a history of psychosis or substance abuse (17.3%), and synthetic cannabis use (5.9%). More respondents in U.S. legal recreational cannabis states reported nonadherence than those in jurisdictions where recreational cannabis remained illegal. Specifically, consumers in U.S. legal states were significantly more likely to use high-tetrahydrocannabinol products than consumers in U.S. illegal states or Canada and more likely to drive after cannabis use than consumers in Canada (p<0.001 for all). Adherence to Lower-Risk Cannabis Use Guidelines was strongly associated with Alcohol, Smoking and Substance Involvement Screening Test scores. Lower-Risk Cannabis Use Guideline adherence differed by jurisdiction and sociodemographic profile. As more jurisdictions legalize nonmedical cannabis, targeted interventions for key risk behaviors (e.g., using high-potency cannabis, early initiation age, driving after cannabis use) are warranted.