Cannabis policy liberalization is only associated with increased blunt use if states lack strong tobacco control

Introduction: Co-use of tobacco and cannabis has long been an issue for prevention and intervention efforts targeting these substances. Blunt use - cannabis inside a cigar wrapper - has been a consistent mode of cannabis consumption since the 1990s. Since then, both tobacco control and cannabis policies have changed considerably. This paper examines the influence of tobacco taxes and smoke-free policies as well as medical and recreational cannabis policies on blunt use among young people. Methods: Combining state-level tobacco control and cannabis policy data with the restricted-access youth cohort of the Population Assessment of Tobacco and Health (PATH) study, we use multilevel logistic regression models to examine the impact of these policies on past-year blunt use. Results: While we found a main effect whereby both legal medical and recreational cannabis policies are associated with higher odds of blunt use among youth, interaction effects demonstrate that this association only emerges in states lacking a comprehensive tobacco smoke-free policy. In states with smoke-free policies, we found no significant associations between cannabis policy and odds of blunt use. Conclusions: Denormalization through smoke-free policies may mitigate the effects of recreational and medical cannabis policies on blunt use. Smoke-free policies represent a possible cost-effective mechanism to curb the couse of tobacco and cannabis in the form of blunts. States with medical and recreational cannabis policies may benefit from greater prevention efforts for young people specifically focused on blunt use, especially in states that do not have strong tobacco control.