A new study published yesterday in the journal PLoS One reports the results of the first-ever clinical trial of electronic cigarettes.
(See: Caponnetto P, et al. Efficiency and safety of an electronic cigarette as tobacco cigarettes substitute: A prospective 12-month randomized control design study. PLos One 8(6): e66317.)
In this study, a group of 300 smokers with no interest in quitting were randomized to one of three groups:
A: Electronic cigarettes with 7.2 mg nicotine cartridges for 12 weeks
B: Electronic cigarettes with 7.2 mg nicotine cartridges for 6 weeks, then 5.4 mg nicotine cartridges for 6 weeks
C: Electronic cigarettes with 0 mg nicotine cartridges
The subjects were followed for one year. Smoking cessation was verified with exhaled carbon monoxide measurements.
The follow-up rate ranged from 55% to 65%. Because of the loss to follow-up, an intent-to-treat analysis was used.
The major result was that the 12-month smoking cessation rate for group A was 13%. For all three groups combined, the cessation rate was 7.8%.
Surprisingly, of those who quit smoking, 70% also quit using electronic cigarettes.
The Rest of the Story
Opponents of electronic cigarettes can no longer argue that claims of the effectiveness of this product for smoking cessation are based solely on anecdotal or survey evidence. We now have clinical trial evidence that these devices can be useful in smoking cessation, even among a population of smokers which had no interest in quitting. Despite this worst-case scenario, a 13% cessation rate was achieved after one year with the group that received 7.2 mg nicotine cartridges for 12 weeks, and the overall cessation rate was 7.8%.
It is difficult to compare these figures to those observed with NRT because NRT clinical trials involved smokers who wanted to quit. However, as I noted in a recent article, the 12-month smoking cessation rate for NRT in clinical trials with biochemical confirmation of smoking cessation is on the order of approximately 12%. Thus, electronic cigarettes in this trial performed about as well among non-motivated smokers as NRT performed among highly motivated smokers. Thus, this trial provides preliminary evidence that electronic cigarettes are more effective than traditional NRT treatment.
Opponents of electronic cigarettes can also no longer argue that smokers who quit using electronic cigarettes are merely substituting one addiction for another. More than 70% of the smokers who quit using electronic cigarettes actually quit using e-cigarettes as well. It appears that switching to electronic cigarettes may facilitate the process of quitting nicotine use altogether. This lessens any concern that electronic cigarettes might maintain nicotine addiction among smokers who would otherwise have quit smoking and completely ended their nicotine use.
The use of electronic cigarettes in the ECLAT trial was also associated with a dramatic reduction in respiratory symptoms, including shortness of breath. Thus, this study provides the first rigorous scientific evidence that electronic cigarette use improves smokers' health.
Future research should refine ECLAT in two ways: (1) test electronic cigarettes among smokers who are motivated to quit; and (2) compare electronic cigarettes and NRT head-to-head.