E-Cigarette Might Help Smokers Quit
BARCELONA -- A nicotine-dispensing electronic cigarette helped smokers quit at least as much as nicotine patches did, a clinical trial showed.
At 6 months, 7.3% using the e-cigarette were biochemically-verified as abstinent compared with 5.8% on the patch and 4.1% using a placebo e-cigarette without nicotine, Christopher Bullen, MBChB, MPH, PhD, of the University of Auckland, New Zealand, and colleagues found.
Those modest differences weren't enough to prove statistically significant superiority, though they did meet the threshold for non-inferiority in a post-hoc analysis.
While the low quit rates left the trial underpowered, they came in the context of little additional behavioral support, akin to what would occur in the community, the group pointed out.
These battery-powered devices, which vaporize nicotine for inhalation, have some practical advantages over nicotine replacement therapy, Peter Hajek, PhD, CClinPsych, of the UK Centre for Tobacco and Alcohol Studies at Queen Mary University of London, noted.
In the U.S. and most other countries, e-cigarettes are regulated as tobacco rather than as medication and so are easy to access without the expense of going to a health professional, he explained in an accompanying editorial.
With at least tentative evidence of equivalence in efficacy, "stop-smoking services which distribute nicotine replacement therapy with minimum support now have a cheaper alternative to consider, and health professionals will now hopefully feel easier about recommending e-cigarettes to smokers, or at least condoning their use," he wrote.
The device's greater acceptability by smokers without extra side effects, as shown in the trial, could translate to a population health benefit, Bullen's group suggested.
Still, they cautioned that an adequately powered e-cigarette study needs to be done "to clearly establish their overall benefits and harms at both individual and population levels."
The trial included 657 smokers in Auckland who wanted to quit. They were randomized to at-will use of the most popular brand of nicotine e-cigarettes there (Elusion, each containing 16 mg), a daily nicotine patch (21 mg), or placebo e-cigarettes without nicotine.
These treatments were started a week before and continued until 12 weeks after participants' quit day.
For the primary endpoint of continuous 6-month biochemically-verified abstinence, the difference between nicotine e-cigarette and patches was 1.51 percentage points, which wasn't significant (95% CI –2.49 to 5.51).
The difference between the nicotine-dispensing device and the placebo device was wider at 3.16 percentage points, but again without statistical significance (95% CI –2.29 to 8.61).
The study had been powered based on 7-day point prevalence tobacco abstinence, but that rate didn't turn out significantly better with the nicotine e-cigarette either.
The nicotine e-cigarette did come out ahead in turning down the volume on tobacco smoking, though.
It cut mean consumption by two cigarettes per day more than the patch (P=0.002). And the proportion that had at least halved the number of tobacco cigarettes smoked by 6 months was 57% with the e-cigarette compared with 41% on the patch (P=0.0002).
Relapses also occurred later, at a median 35 days with the nicotine e-cigarette compared with 14 days with the patch (P<0.0001) and 12 with placebo (P=0·09).
The device was also more popular in terms of whether participants would recommend it to a friend and had better adherence.
Adverse events with the nicotine e-cigarette were generally not serious; the adverse event rate didn't differ from that of the patch (incidence rate ratio 1.05, P=0.7).
"However, longer-term use requires more research," the researchers cautioned.
All participants were also able to call a quitline for telephone counseling or receive text message support, though only 36% to 40% across the groups did so.
"Addition of more intensive support might have improved quit rates, but it would also have misrepresented the typically low support environment in which most e-cigarette users attempt to quit," the researchers noted.
Lack of careful supervision and monitoring of adherence, typical of a trial for a new treatment, was a limitation, Hajek pointed out.
Other limitations were the higher loss to follow-up and withdrawal rate in the patch group and the use of earlier generation e-cigarette models with low nicotine delivery compared with tobacco cigarettes.
Notably, a third of the e-cigarettes group continued to use them at 6 months, beyond the intervention period, "suggesting that they might have become long-term e-cigarette users." Some who went back to smoking continued to use e-cigarettes atop reduced cigarette consumption.
That kind of replacement is the "main untapped potential of e-cigarettes" given the lower risk of lung cancer expected from getting rid of the many carcinogens of smoked tobacco, Hajek pointed out.
However, there have been concerns that e-cigarettes could "renormalize" smoking and pull in new recruits, Hajek pointed out.
A report out this week in the CDC's Morbidity and Mortality Weekly Report pointed to a modest increase in e-cigarette use among middle and high school kids, but the vast majority of those who'd ever tried it already smoked conventional cigarettes.
The study was funded by the Health Research Council of New Zealand.
The e-cigarettes and cartridges were Elusion brand products provided by PGM International.
Bullen reported having done research on Ruyan brand e-cigarettes that was funded by Health New Zealand, independently of Ruyan.
Co-authors reported financial relationships with Ruyan and manufacturers of smoking cessation drugs.
Hajek reported having received research funding from and consulting for manufacturers of smoking cessation medication but disavowed any connections with any manufacturers of electronic cigarettes.