Cannabis use and driving under the influence: Behaviors and attitudes by state-level legal sale of recreational cannabis

Background: As states continue to legalize the sale of recreational cannabis, there is a need to study attitudes and behaviors regarding driving after cannabis use. The purpose of this study was to describe US adults' attitudes and behaviors regarding driving after cannabis use by state-level legal sale of recreational cannabis, and to determine whether these associations differ by frequency of cannabis use. Methods: Data were collected from a national sample of 17,112 adults in the United States. Weighted adjusted prevalence ratios and 95% confidence intervals were used to compare the prevalence of behaviors and attitudes by state-level legal sale of recreational cannabis. Analyses were repeated among recent cannabis users, stratifying by cannabis use status. Results: Driving after cannabis use was more prevalent in legal cannabis sales states; however, so were potentially protective attitudes related to cannabis use and driving. After stratifying by frequency of use, daily/almost daily, weekly/monthly, and past 12-month users from states with legal recreational cannabis sales had significantly lower prevalence of driving after cannabis use and higher prevalence of protective attitudes compared to those from states without legal recreational sales. Risk perceptions were lower for cannabis than alcohol. Conclusions: Public health messaging campaigns to reduce driving and riding after cannabis use and to improve attitudes regarding driving after cannabis use are warranted across all U.S. states, regardless of legalization status.