An important study comparing e-cigarettes with nicotine replacement therapy (NRT) has been published in a leading journal and the main finding is a boost for e-cigs – they were found to be more effective than NRT for smoking cessation, when both methods were backed up by behavioural support.
Published in the US-based New England Journal of Medicine, this latest study highlights the gulf in acceptance of vaping between the US and UK, where the study was conducted.
Led by Peter Hajek at Queen Mary University of London, it was a randomised trial of e-cigs versus NRT. The authors assigned people attending UK NHS stop smoking services to either NRT products of their choice or to a second-generation e-cig starter pack, with a recommendation to buy e-liquids of their choice of flavour and strength. At least four weeks of behavioural support was provided.
The striking finding was that the one-year rate of abstinence from smoking was 18% in the e-cig group compared with 9.9% in the NRT group. The report says this “is particularly noteworthy given that nicotine replacement was used under expert guidance, with access to the full range of nicotine-replacement products and with 88.1% of participants using combination treatments”.
This is a stronger effect than other trials of e-cigs in smoking cessation, the authors say. They detail the previous limited evidence and there appears to be only one other recent study, which had very low abstinence rates that were “reflective of the study design”.
The relative success of the trial by Hajek and co could be because people attending stop smoking services are motivated to quit, plus the face-to-face support and the use of refillable e-cigs with free choice of e-liquids. “Previous trials provided limited or no face-to-face support and used first-generation cartridge products. Refillable devices are generally more efficient at nicotine delivery,” the authors note.
Also included in the study were observations on health effects, such as that e-cigs caused more throat or mouth irritation, while NRT caused more nausea.
There was a mixed result on respiratory effects, with more e-cig users having adverse events than NRT users, but e-cigs users also had fewer respiratory infections (possibly because of the antibacterial effects of propylene glycol and glycerine).
A limitation is that this is not a “blinded” study, and people in the NRT group may have regarded their products as inferior and not made as much effort, although the authors say they tried to recruit only participants with no strong product preference, and the NRT result was in line with other studies.
A concern, also voiced in an accompanying editorial in the NEJM, is the possible long-term effects of continuing to use e-cigs. However, Hajek et al say that “ongoing e-cigarette use may ameliorate withdrawal symptoms, such as constipation, mouth ulcers, and weight gain, and continue to provide some of the positive subjective effects previously derived from smoking”.
Long-term e-cig use may also help prevent relapse in heavy smokers, given that the same effects as long-term NRT use apply. Their findings, the authors comment, are likely to be valid for dependent smokers who seek help.
The view from the US
Another concern is the impact that adult use of e-cigs may have on children and young adults.
“It remains controversial whether e-cigarettes should be recommended as a first-line treatment to assist smoking cessation, alongside FDA-approved treatments,” write the editorial authors from a US standpoint. They add: “We recommend that e-cigarettes be used only when FDA-approved treatments (combined with behavioural counselling) fail, that patients be advised to use the lowest dose needed to manage their cravings, and that there be a clear timeline and ‘off ramp’ for use.”
NRT has for long time been the main pharmacotherapy used in smoking cessation programmes, with other choices being the drugs varenicline and bupropion. Health authorities have so far mostly stopped short of approving e-cigs as medicinal stop-smoking products, while noting that many people have found them helpful as quit aids.
The UK medicines regulator, the Medicines and Healthcare Products Regulatory Agency (MHRA), did approve Voke, an electronic inhaler made by British American Tobacco (BAT), as a smoking cessation aid in 2015 but it has not been brought to market.
Last year, a report by the UK House of Commons Science and Technology Committee reviewed the evidence for e-cigs, including their use for smoking cessation, and recommended streamlining the process by which medically licensed products could be made available. It’s a moot point whether an e-cig product is likely to be obsolete by the time the current lengthy approval process is completed.
What This Means: While its conclusions are strongly supportive of vaping as an aid to smoking cessation, this UK report perhaps marks a further widening of the gap between the UK and other jurisdictions on the positive utility of e-cigs. The study by Hajek et al give this standpoint more ammunition – although only in the context of UK stop smoking services. The authors say more trials are needed to see if the results can be generalised elsewhere.