Electronic cigarettes for smoking cessation: an individual patient meta-analysis of randomized controlled trials

Abstract

Background: Electronic cigarettes have been gaining popularity as smoking cessation tools worldwide but its safety and effectiveness compared to placebo and nicotine replacement therapy (NRT) is still undefined. Randomized controlled trials are severely lacking and conflicting in results. Methods: We conducted a meta-analysis of individual patient data involved in randomized controlled trials examining the effectiveness of e-cigarettes vs. NRT or placebo primarily in terms of sustained abstinence rates at six months. Safety was assessed via the incidence of any serious adverse events. Results: Six randomized controlled trials were included in the analysis. The most recent study was published in 2019. Six-month sustained abstinence rate was higher in the e-cigarette versus NRT group, 1.69 (1.30, 2.21). Consistently, six-month abstinence rate in e-cigarette group was superior to placebo, 2.37 (1.19, 4.74). There was a trend toward increased total serious adverse in the e-cigarette group vs. NRT, although this is not significant, RR= 1.42 (0.94, 2.12). Conclusions: In our meta-analysis, we illustrated that e-cigarettes were superior to both NRT and placebo in inducing sustained smoking abstinence. However, the safety of e-cigarettes is not clearly assessed and more randomized controlled trials are definitely needed.