Real-world effectiveness of e-cigarettes when used to aid smoking cessation: a cross-sectional population study

Background and Aims Electronic cigarettes (e-cigarettes) are rapidly increasing in popularity. Two randomized controlled trials have suggested that e-cigarettes can aid smoking cessation, but there are many factors that could influence their real-world effectiveness. This study aimed to assess, using an established methodology, the effectiveness of e-cigarettes when used to aid smoking cessation compared with nicotine replacement therapy (NRT) bought over-the-counter and with unaided quitting in the general population. Design and Setting A large cross-sectional survey of a representative sample of the English population. Participants The study included 5863 adults who had smoked within the previous 12 months and made at least one quit attempt during that period with either an e-cigarette only (n = 464), NRT bought over-the-counter only (n = 1922) or no aid in their most recent quit attempt (n = 3477). Measurements The primary outcome was self-reported abstinence up to the time of the survey, adjusted for key potential confounders including nicotine dependence. Findings E-cigarette users were more likely to report abstinence than either those who used NRT bought over-the-counter [odds ratio (OR) = 2.23, 95% confidence interval (CI) = 1.70-2.93, 20.0 versus 10.1%] or no aid (OR = 1.38, 95% CI = 1.08-1.76, 20.0 versus 15.4%). The adjusted odds of non-smoking in users of e-cigarettes were 1.63 (95% CI = 1.17-2.27) times higher compared with users of NRT bought over-the-counter and 1.61 (95% CI = 1.19-2.18) times higher compared with those using no aid. Conclusions Among smokers who have attempted to stop without professional support, those who use e-cigarettes are more likely to report continued abstinence than those who used a licensed NRT product bought over-the-counter or no aid to cessation. This difference persists after adjusting for a range of smoker characteristics such as nicotine dependence.