E-cigarette and combusted tobacco abstinence among young adults: Secondary analyses from a U.S.-based randomized controlled trial of vaping cessation

OBJECTIVE: To examine patterns of abstinence from e-cigarettes, combusted tobacco products (CTPs), both, or neither among young adults enrolled in a U.S.-based randomized trial of a text message vaping cessation intervention. METHODS: At baseline, 1829 young adult e-cigarette users were categorized as Exclusive E-cigarette Users (no past 30-day CTP use; n = 1036, 56.6%) or Dual Users (past 30-day CTP use; n = 793, 43.4%). Four groups were defined at 7-months: 1) Dual Abstinent, 2) Exclusive Vaping, 3) Exclusive CTP Use, and 4) Dual Users. The proportion of participants who were Dual Abstinent was the outcome of interest. RESULTS: At follow-up, 22.1% (95% CI: 20.3, 24.1) of participants were Dual Abstinent, 44.8% (95% CI: 42.5, 47.1) reported Exclusive Vaping, 6.3% (95% CI: 5.2, 7.5) reported Exclusive CTP Use, and 26.8% (95% CI: 24.8, 28.9) were Dual Users. A higher proportion of participants randomized to Intervention were Dual Abstinent (25.9%, 95% CI 23.1, 28.9) compared to Control (18.5%, 95% CI 16.0, 21.1; p = .0002). Analyses of treatment effects on dual abstinence by baseline tobacco product use favored Intervention over Control among both Exclusive E-cigarette Users (p = .019) and Dual Users (p = .0014). CONCLUSION: A text message vaping cessation intervention was effective in promoting dual abstinence from e-cigarettes and CTPs among young adults. The advantage of treatment over control was equivalent for Exclusive E-cigarette Users and Dual Users. Rates of dual abstinence were higher among exclusive vapers than dual users, signaling the need for more research to optimize cessation programs for poly-tobacco users