E-cigarettes that contain nicotine can help people quit smoking long-term or reduce the number of cigarettes they smoke compared with those products that do not contain nicotine, according to the findings of a review published on 17 December 2014 by the Cochrane Library
The review considered the results of two randomised controlled trials involving 662 smokers. The studies revealed that 9% of smokers who used nicotine-containing e-cigarettes were able to give up smoking within a year. This was more than double the 4% quit rate for smokers using non-nicotine containing products (risk ratio 2.29, 95% confidence interval 1.05 to 4.96).
It also showed there were no serious adverse health effects associated with use of the products in the short to mid-term.
The researchers warn that although the findings are encouraging, more research is needed to give confidence to their conclusions because the review was based on the outcomes of just two trials with a limited number of participants.
The team could not determine if e-cigarettes were better than a nicotine patch in helping people stop smoking because the number of study participants was too low.
Analysis of data on cigarette consumption also showed promising results. “In terms of cigarette consumption, nicotine-containing e-cigarettes were significantly more effective than placebo e-cigarettes and also significantly more effective than nicotine patches in helping people achieve 50% or greater reduction in smoking.”
The researchers say there is an urgent need for evidence about the impact of e-cigarettes.
“Smokers report using e-cigarettes to reduce risks of smoking, but some healthcare organisations have been reluctant to encourage smokers to switch to electronic cigarettes, citing lack of evidence of efficacy and safety,” they write. “Smokers, healthcare providers and regulators are interested to know if these devices can reduce the harms associated with smoking. In particular, healthcare providers have an urgent need to know what advice they should give to smokers enquiring about e-cigarettes.”
Anthony Cox, a lecturer in clinical pharmacy at the University of Birmingham and a member of the Royal Pharmaceutical Society’s English Pharmacy Board, welcomes the review because it provides the medicines safety regulator, the Medicines and Healthcare products Regulatory Agency, with further evidence to allow a licensed e-cigarette product to be sold in pharmacy.
“The issue isn’t about whether e-cigarettes are good or bad – it’s about what the evidence says,” he argues. “If the evidence says that they work then there should be licenced products which can be sold in pharmacies.”
 McRobbie H, Bullen C, Hartmann-Boyce J et al. Electronic cigarettes for smoking cessation and reduction. Cochrane Database of Systematic Reviews 2014, Issue 12. Art. No.: CD010216. doi: 10.1002/14651858.CD010216.pub2.