Exposure to ENDS advertising and use of marijuana in ENDS among college students

Background: Factors associated with marijuana use in electronic nicotine delivery systems (ENDS) are largely unknown. ENDS advertising, through subtle normative cues as well as explicit and implicit messages suggesting ENDS products are socially condoned and healthier alternatives, may influence the use of marijuana in ENDS. The aim of our study was to examine the association between exposure to ENDS advertising and subsequent use of ENDS with marijuana among college students. Methods: Data for this study were from waves 2 and 4 of the Marketing and Promotions across Colleges in Texas (M-PACT) study. Participants included 3720 college students (mean age = 21.4, SD = 2.3; 35.78% white; 35.7% male) across 24 colleges in Texas who completed online tobacco behavior surveys one year apart. Multilevel logistic regression was conducted to examine the association between ENDS advertising exposure at wave 2 (spring 2015) and use of marijuana in ENDS one year later at wave 4 (spring 2016), controlling for age, sex, race/ethnicity, and wave 2 sensation-seeking, impulsivity, current tobacco use, current marijuana use, and ever use of ENDS with marijuana. Use of ENDS to consume marijuana in the past six months was the outcome variable and ENDS advertising exposure was the independent variable. Results: Nearly half of participants reported ever ENDS use at waves 2 and 4, and 10% used marijuana in ENDS in the past 6-months at wave 4. Multilevel logistic regression analyses indicated that for every unit increase in ENDS advertising exposure, the odds of subsequently using ENDS with marijuana one year later were 1.08 times (95% CI = 1.01-1.14) greater. Conclusions: ENDS advertising uniquely contributed to the subsequent use of marijuana in an ENDS, over and above the effects of other risk factors.