Friday, February 1, 2019

NEJM study provides evidence of greater efficacy of e-cigarettes vis-à-vis conventional NRTs

One of the most pressing unanswered questions in public health has been "Do e-cigarettes actually help smokers quit?"

The first, large rigorous assessment now answers this question.

A study, published Wednesday in the New England Journal of Medicine, found that e-cigarettes were nearly twice as effective as conventional nicotine replacement products, like patches and gum, for quitting smoking, reports New York Times. The success rate was 18% among the e-cigarette group, compared to 9.9% among those using traditional nicotine replacement therapy.

The study was conducted in Britain and funded by the National Institute for Health Research and Cancer Research UK. For a year, it followed 886 smokers assigned randomly to use either e-cigarettes or traditional nicotine replacement therapies. Both groups also participated in at least four weekly counseling sessions, an element regarded as critical for success.

E-cigarettes provide the nicotine smokers crave without the toxic tar and carcinogens that come from inhaling burning tobacco. But, it is still not approved as smoking cessation tools. 

Doctors up till now were reluctant to recommend their use because of the lack of clear evidence from randomized controlled trials. This is now likely to change.

The New England Journal devoted much of its current issue to e-cigarettes, publishing two editorials and a letter, and the collection embodies the tangled public health debate over the devices.  One editorial — written by Belinda Borrelli, a behavioral health expert and Dr. George T. O’Connor, a pulmonologist — pumped the brakes on inclinations to embrace e-cigarettes.

The editorial recommended that e-cigarettes be taken up when other cessation approaches, including behavioral counselling have failed; that patients use the lowest dose of nicotine possible and that health care providers establish a clear timeline for
e-cigarette use.

The clinical trial took place from May 2015 to February 2018. Because the smokers were recruited at the clinics, they were already predisposed to quitting, a feather on the scale that could slightly have affected results. The participants were typically middle-aged, smoked between half a pack and a pack a day and had already tried quitting.

Because self-reports of smoking abstinence are not considered reliable, researchers measured the quantities of carbon monoxide in the participants’ breath, a more precise validation. Higher quit rates and compliance among e-cigarette users could be additionally explained because those subjects expressed more satisfaction with the devices than did the other group with their products.
Some researchers hypothesize that because a body takes in only the amount of nicotine it needs to maintain a certain level, high-nicotine products could have the advantage of delivering that power punch with fewer puffs, decreasing the amount of harmful aerosol a vaper would inhale.

(Source: New York Times)

NEJM Abstract

A randomized trial of e-cigarettes vs nicotine-replacement therapy

Hajek P, Phillips-Waller A, Przulj D, et al. N Engl J Med. 2019 Jan 3. Epub ahead of print

Background: E-cigarettes are commonly used in attempts to stop smoking, but evidence is limited regarding their effectiveness as compared with that of nicotine products approved as smoking-cessation treatments.

Methods: We randomly assigned adults attending U.K. National Health Service stop-smoking services to either nicotine-replacement products of their choice, including product combinations, provided for up to 3 months, or an e-cigarette starter pack (a second-generation refillable e-cigarette with one bottle of nicotine e-liquid [18 mg per milliliter]), with a recommendation to purchase further e-liquids of the flavor and strength of their choice. Treatment included weekly behavioral support for at least 4 weeks. The primary outcome was sustained abstinence for 1 year, which was validated biochemically at the final visit. Participants who were lost to follow-up or did not provide biochemical validation were considered to not be abstinent. Secondary outcomes included participant-reported treatment usage and respiratory symptoms.

Results: A total of 886 participants underwent randomization. The 1-year abstinence rate was 18.0% in the e-cigarette group, as compared with 9.9% in the nicotine-replacement group (relative risk, 1.83; 95% confidence interval [CI], 1.30 to 2.58; P<0.001). Among participants with 1-year abstinence, those in the e-cigarette group were more likely than those in the nicotine-replacement group to use their assigned product at 52 weeks (80% [63 of 79 participants] vs. 9% [4 of 44 participants]). Overall, throat or mouth irritation was reported more frequently in the e-cigarette group (65.3%, vs. 51.2% in the nicotine-replacement group) and nausea more frequently in the nicotine-replacement group (37.9%, vs. 31.3% in the e-cigarette group). The e-cigarette group reported greater declines in the incidence of cough and phlegm production from baseline to 52 weeks than did the nicotine-replacement group (relative risk for cough, 0.8; 95% CI, 0.6 to 0.9; relative risk for phlegm, 0.7; 95% CI, 0.6 to 0.9). There were no significant between-group differences in the incidence of wheezing or shortness of breath.

Conclusions: E-cigarettes were more effective for smoking cessation than nicotine-replacement therapy, when both products were accompanied by behavioral support.
(Funded by the National Institute for Health Research and Cancer Research UK; Current Controlled Trials number, ISRCTN6047760) 

Dr KK Aggarwal
Padma Shri Awardee
President Elect Confederation of Medical Associations in Asia and Oceania   (CMAAO)
Group Editor-in-Chief IJCP Publications
President Heart Care Foundation of India
Past National President IMA

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