Association between ENDS device and liquid characteristics and cigarette smoking, quitting and smoking reduction behaviors among U.S. adults who frequently use ENDS.

introductionElectronic nicotine delivery systems (ENDS) may support cigarette cessation. We examine whether ENDS device and liquid characteristics are associated with cigarette smoking cessation and reduction.

methodsData are from U.S. adults (21 +) who used ENDS ≥ 5 days/week of a longitudinal study. Participants included 202 adults who completed Wave 3 (September-November 2021) and 4 (July-September 2022) and smoked in Wave 3; and 196 adults who completed Wave 4 and 5 (February-April 2023) and smoked in Wave 4. Cigarette quitting was defined as smoking at the prior wave and not smoking at follow-up. Cigarette reduction was defined as reducing daily cigarette consumption by ≥ 50% at follow-up. Rao-Scott Chi-Square tests and mixed-effects models were conducted.

results32.2% of participants (n = 128) reported not smoking at a subsequent wave. Fewer years of smoking cigarettes, fewer cigarettes smoked/day, lower cigarette dependence, and lower likelihood of using any additional tobacco product were significantly associated with quitting (p < 0.05); however, device type, wattage, nicotine concentration, nicotine formulation, and flavor were not significantly associated with quitting. Participants who used non-tobacco flavored ENDS and smoked more cigarettes/day were more likely to report smoking reduction at follow-up in bivariate analyses (p < 0.05), but not in adjusted models.

conclusionsAmong U.S. adults using ENDS ≥ 5 days/week alongside cigarette smoking, device and liquid characteristics were not associated with quitting behaviors or smoking reduction 6-12 months later in adjusted models. The study's limitations underscore the need for larger longitudinal and randomized studies tracking diverse ENDS characteristics, cigarette cessation, and reduction over time.