Correlates of e-cigarette use among adults initiating smoking cessation treatment.

Abstract

Little is known about the correlates of e-cigarette (EC) use among adults seeking smoking cessation treatment, and it is unclear how EC use affects smoking treatment outcomes. Participants were 649 adult smokers enrolled in smoking cessation treatment. Participants completed a baseline (pre-quit) assessment with follow-up at 4-, 12-, and 26-weeks after a scheduled combustible cigarette (CC) cessation date. EC use was described before and after the CC cessation date, and the impact of baseline EC use on CC cessation at follow-up was evaluated. At baseline, 66.6 % of participants had ever-used ECs and 23.1 % reported past 30-day EC use. Past 30-day EC users were younger, more socioeconomically disadvantaged, more CC dependent, and less likely to report Black race compared to non-users. At the 4-, 12-, and 26-week follow-ups, 6.4 %, 7.4 %, and 8.1 % reported dual EC/CC use; and 2.7 %, 3.4 %, and 2.7 % had switched to exclusive EC use. Past 30-day EC use at baseline was not associated with CC cessation at any follow-up. However, among baseline past 30-day EC users (n = 150), using ECs ≥ once per week was associated with a lower likelihood of CC cessation at 26-week follow-up (adjusted OR 0.346, 95 % CI: 0.120, 0.997). Findings indicated that dual users of CCs and ECs at baseline differed from CC-only users on sociodemographic and smoking characteristics. Baseline EC use did not impact smoking cessation overall. However, among past 30-day users, more frequent EC use at baseline adversely impacted longer-term cessation outcomes, perhaps due to greater baseline CC/nicotine dependence.