E-Cigarettes and Smoking Cessation: Evidence from a Systematic Review and Meta-Analysis

Abstract

BackgroundE-cigarettes are currently being debated regarding their possible role in smoking cessation and as they are becoming increasingly popular, the research to date requires investigation.ObjectivesTo investigate whether the use of e-cigarettes is associated with smoking cessation or reduction, and whether there is any difference in efficacy of e-cigarettes with and without nicotine on smoking cessation.Data SourcesA systematic review of articles with no limit on publication date was conducted by searching PubMed, Web of Knowledge and Scopus databases.MethodsPublished studies, those reported smoking abstinence or reduction in cigarette consumption after the use of e-cigarettes, were included. Studies were systematically reviewed, and meta-analyses were conducted using Mantel-Haenszel fixed-effect and random-effects models. Degree of heterogeneity among studies and quality of the selected studies were evaluated.ResultsSix studies were included involving 7,551 participants. Meta-analyses included 1,242 participants who had complete data on smoking cessation. Nicotine filled e-cigarettes were more effective for cessation than those without nicotine (pooled Risk Ratio 2.29, 95%CI 1.05-4.97). Amongst 1,242 smokers, 224 (18%) reported smoking cessation after using nicotine-enriched e-cigarettes for a minimum period of six months. Use of such e-cigarettes was positively associated with smoking cessation with a pooled Effect Size of 0.20 (95%CI 0.11-0.28). Use of e-cigarettes was also associated with a reduction in the number of cigarettes used.LimitationsIncluded studies were heterogeneous, due to different study designs and gender variation. Whilst we were able to comment on the efficacy of nicotine vs. non-nicotine e-cigarettes for smoking cessation, we were unable to comment on the efficacy of e-cigarettes vs. other interventions for cessation, given the lack of comparator groups in the studies included in this meta-analysis.ConclusionsUse of e-cigarettes is associated with smoking cessation and reduction. More randomised controlled trials are needed to assess effectiveness against other cessation methods.

Characteristics of e-cigarette users and their perceptions of the benefits, harms and risks of e-cigarette use: survey results from a convenience sample in Ottawa, Canada

“…13,16,17 Even though there is evidence that e-cigarettes are effective in reducing or eliminating cigarette consumption, this finding is not consistent. 18,19 Although e-cigarette awareness and use are increasing in Canada, there have been few attempts to describe e-cigarette users. 9,12,20,21 An online survey of 1188 young adults found that 43% were aware of e-cigarettes and 5.7% were current e-cigarette users.…”

Use of Electronic Nicotine Delivery Systems Among Adolescents: Status of the Evidence and Public Health Recommendations

“…Some randomized controlled trials [59][60][61] testing the efficacy of ENDS in smoking cessation have found a benefit of ENDS over smoking cessation aids currently approved by the FDA, but it is clear that more research regarding the safety and efficacy of ENDS is necessary before they can be used as smoking cessation tools. More importantly, although the premise of the harm reductionism argument may be valid among an adult population, it should not be applied to children's experimentation with and use of ENDS.…”

E-Cigarettes: The Science Behind the Smoke and Mirrors

“…However, existing nicotine replacement therapy products were developed within formal pharmaceutical processes and marketed and sold under governmental regulation, whereas to date, randomized control trials of e-cigarettes from various manufacturers have failed to demonstrate efficacy. Of the 3 meta-analyses in press, 2 found a probable increase in cessation, 47,48 whereas a third, 49 taking into account more non-controlled and observational trials, found that they may suppress cessation, indicating that the current literature is insufficient to make firm conclusions in either direction.…”

“…The pooled results of these 2 trials indicate that nicotine-containing e-cigarettes outperform placebo e-cigarettes (RR 2.29). 47,48 Notably, both of these trials used early generations of e-cigarettes with a lower delivery of nicotine than current devices on the market.…”