Electronic nicotine delivery systems for smoking cessation: where are we?

Abstract

Electronic cigarettes (e-cigarettes) have surged in popularity since their introduction in 2007. Sales of e-cigarettes and related products in the US were expected to exceed $1B in 2013. With the popularity of the electronic cigarette on the rise, physicians are sure to get questions from patients about the safety of e-cigarettes and their effectiveness as tools for smoking cessation or reduction. Most users of the electronic cigarette are so-called dual users—current cigarette smokers who also use e-cigarettes. The appeal of these devices is largely based on a perception that they are not as harmful as traditional cigarettes. Other factors that contribute to the popularity of e-cigarettes are that they have the look and feel of a traditional cigarette, that they can be used in locations where cigarette smoking is forbidden, and that they are perceived by smokers as tools to help to reduce or eliminate the smoking of traditional cigarettes. At present, e-cigarettes are not formally regulated for safety or quality control. As a result, nicotine delivery with these devices is not consistent. There is significant concern in the medical community that these e-cigarettes may not be as safe as is publicly perceived, particularly in the context of dual use. The use of e-cigarettes in harm-reduction strategies is a very divisive one in the public health arena. During the last few years, there have been longitudinal, cross-sectional, and randomized clinical trials evaluating the efficacy of electronic cigarettes as smoking cessation aids. This review presents a focused analysis of these studies.