Cannabis use and route-specific administration among U.S. adults who do and do not use tobacco: Findings from the 2024 Health Information National Trends Survey.

BACKGROUND: Cannabis use is common among people who use tobacco, however, few studies have examined route-specific cannabis use in the context of tobacco. This study provides nationally representative 2024 prevalence estimates for overall and route-specific cannabis use by tobacco use status. METHODS: Data were from the nationally representative 2024 Health Information National Trends Survey (N = 6328). Measures included past 12-month cannabis use and route of administration (smoking; vaping; dabbing; eating/drinking (consumed); applying a lotion; 2+ routes) and current any tobacco use. Multivariable logistic regression models examined the association between current tobacco use and past 12-month route-specific cannabis use, adjusting for state-level cannabis legality, reasons for use, and sociodemographic characteristics. RESULTS: An estimated 23.1% of US adults reported past 12-month cannabis use: 62.6% smoked, 57.6% consumed, 40.1% vaped, 15.2% applied lotion, and 12.4% dabbed, with over half (52.7%) endorsing >1 route of administration. Cannabis use was higher among adults who currently used tobacco products (46.0%) compared to those who did not (17.4%) (p < 0.001). Among those reporting past 12-month cannabis use, those who currently used tobacco (vs. did not) were more likely to smoke cannabis (73.4% vs. 55.6%, p = 0.001), vape cannabis (52.4% vs. 32.1%, p < 0.001), or use 2+ routes (60% vs 47.9%, p = 0.02). CONCLUSIONS: In 2024, nearly 1 in 2 adults who currently used tobacco reported using cannabis. Current tobacco use was significantly associated with increased likelihood of past 12-month cannabis use. Continued surveillance and research on the interplay of cannabis and tobacco use is needed to understand co-use health effects.