The efficacy and short-term effects of electronic cigarettes as a method for smoking cessation: a systematic review and a meta-analysis
- 2.1k Downloads
E-cigarettes are increasingly popular as smoking cessation aids. This review assessed the efficacy of e-cigarettes for smoking cessation as well as desire to smoke, withdrawal symptoms, and adverse events in adult smokers.
A systematic review was conducted. Studies comparing e-cigarettes to other nicotine replacement therapies or placebo were included. Data were pooled using meta-analysis.
Of 569 articles, 5 were eligible. Study participants were more likely to stop smoking when using nicotine e-cigarettes (43/489, 9 %) versus placebo e-cigarettes (8/173, 5 %); however, this difference was not statistically significant (RR 2.02; 95 % CI 0.97, 4.22). The pooled effect estimates for the desire to smoke (RR −0.22; 95 % CI −0.80, 0.36), irritability (RR −0.03; 95% CI −0.38, 0.31), restlessness (RR −0.03; 95 % CI −0.42, 0.35), poor concentration (RR −0.01; 95 % CI −0.35, 0.32), depression (RR −0.01; 95 % CI −0.22, 0.20), hunger (RR −0.01; 95 % CI −0.32, 0.30), and average number of non-serious adverse events (RR −0.09; 95 % CI −0.28, 0.46) were not statistically significantly different. Only one study reported serious adverse events with no apparent association with e-cigarette use.
Limited low-quality evidence of a non-statistically significant trend toward smoking cessation in adults using nicotine e-cigarettes exists compared with other therapies or placebo. Larger, high-quality studies are needed to inform policy decisions.
KeywordsMeta-analysis E-cigarettes Smoking cessation Withdrawal symptoms Public health
Compliance with ethical standards
Conflict of interest
The author(s) declare no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
The author(s) received no financial support for the research, authorship, and/or publication of this article.
Author contribution statement
SK and DO designed the systematic review and meta-analysis protocol. SK and KC created the search strategy. SK and TD searched for publications, and did the review and data extraction, and LL helped with the disagreements. SK, DO, and RΒ developed the analysis frame. SK and TD did the analysis, and SK and DO critically interpreted the results. SK drafted the article, and all authors provided critical revision of the article.
- Action on Smoking and Health (ASH) (2014) Electronic cigarettes. http://www.ash.org.uk/files/documents/ASH_715.pdf
- Akl EA, Briel M, You JJ et al (2012) Potential impact on estimated treatment effects of information lost to follow-up in randomised controlled trials (LOST-IT): systematic review BMJ Br Med J 344Google Scholar
- Buck SF (1960) A method of estimation of missing values in multivariate data suitable for use with an electronic computer. J Royal Stat Soc Series B (Methodological) 22:302–306Google Scholar
- Higgins JPT, Green S (2011) Cochrane Handbook for Systematic Reviews of Interventions Version 5.1.0 [updated March 2011]. Cochrane CollaborationGoogle Scholar
- Medicines and Healthcare Products Regulatory Agency (MHRA) (2014) Press release: UK moves towards safe and effective electronic cigarettes and other nicotine-containing productsGoogle Scholar
- Orr KK, Asal NJ (2014) Efficacy of electronic cigarettes for smoking cessation. Ann Pharmacotherap 1060028014547076Google Scholar
- Pepper JK, Brewer NT (2013) Electronic nicotine delivery system (electronic cigarette) awareness, use, reactions and beliefs: a systematic review. Tobacco ControlGoogle Scholar
- Stanbrook MB (2013) Regulate e-cigarettes as drug-delivery devices. Can Med Assoc JGoogle Scholar
- World Health Organization (2014) Tobacco. GenevaGoogle Scholar