Current and future trends in electronic cigarette use.

The controversy regarding the use of electronic cigarettes as a possible modality for smoking cessation has grown in recent years. Epidemiologic surveys indicate that usage rates in both adults and adolescents have increased substantially as the popularity of these devices continues to rise. At present, there is a small but growing body of evidence studying the possible role that these "e-cigarettes" may have as a nicotine replacement tool. Much of the existing data are from observational studies and surveys which track the epidemiologic and demographic trends of e-cigarette users. More recently-published articles have begun to utilize randomized, experimental designs to directly compare the efficacy of e-cigarettes to active and passive controls in outcome measures such as conventional cigarette quit rates and time to relapse. Barriers to widespread adoption of e-cigarette use as a smoking cessation modality include a lack of long-term safety and toxicology data, a lack of standardization of devices, and a debate regarding whether devices can be marketed for both social nicotine use, as well as nicotine replacement. A possible role of e-cigarettes that has not yet been explored is in the primary prevention of conventional cigarette use among young adults that are smoking-naïve.