Importance. Vaping has become an increasingly common method for consuming nicotine and cannabis, a trend potentially influenced by e-cigarette marketing. However, little is known about the influence of e-cigarette marketing on cannabis vaping behaviors. Objective. To examine the associations between e-cigarette marketing exposure and nicotine and cannabis vaping behaviors among adults. Design, Setting, and Participants. This cross-sectional study included a U.S. nationally representative sample of adults (≥18 years) from the Wave 6 survey of the Population Assessment of Tobacco and Health (PATH) Study, conducted from March to November 2021. Exposure. Past 30-day e-cigarette marketing exposure (overall and by ten marketing channels). Main Outcomes and Measures. Past 30-day vaping behavior (sole- and dual-vaping of nicotine and cannabis) overall and stratified by age. Results. The study included 30,516 respondents (48.0% male and 63.9% non-Hispanic White). Overall, 52.0% of respondents reported past 30-day e-cigarette marketing exposure, and 89.8%, 5.6%, 3.2%, and 1.4% reported no vaping, sole-nicotine vaping, sole-cannabis vaping, and dual-vaping, respectively. Multinominal logistic regression results show exposure to e-cigarette marketing was associated with increased odds of reporting sole-cannabis vaping versus no vaping (adjusted risk ratio [aRR], 1.31; 95% confidence interval [CI], 1.09-1.57) and dual-vaping versus no vaping (aRR, 1.26; 95% CI, 1.01-1.57). Stratification analysis found these associations among those aged 18-24 and 25-34 years but not older adults (≥35 years). Those exposed to e-cigarette marketing also had increased odds of reporting sole-cannabis vaping versus sole-nicotine vaping (aRR, 1.28; 95% CI, 1.04-1.58). Stratification analysis found this association only among those aged 18-24 years. E-cigarette marketing exposure via several channels (retail stores, billboards, events, newspapers/magazines) was associated with increased odds of reporting sole-cannabis vaping. Conclusions and Relevance. E-cigarette marketing exposure was only associated with sole-cannabis vaping and dual-vaping, not sole-nicotine vaping among U.S. adults. Such associations were mainly driven by young adults aged 18-24 and 25-35 years and were found for multiple marketing channels. Greater restrictions on tobacco marketing may have reduced the influence of e-cigarette marketing on nicotine vaping, while gaps in such marketing restrictions for cannabis may contribute to continued influence of e-cigarette marketing on cannabis vaping.
