On August 16, according to foreign reports, electronic cigarettes have attracted the attention of the media and consumers due to their addictive nature, multiple flavors and increased use by teenagers, triggering regulation and policy.

These devices could help people reduce their dependence on combustible cigarettes -- which contain a range of harmful chemicals called toxicants -- without increasing their overall dependence on nicotine, according to a Penn State School of Medicine study.

Smoking is the leading cause of death in the United States, and despite the interest in quitting and the availability of FDA-approved ways to quit, smokers still have difficulty quitting.

Some public health experts, citing reports from the National Academies of Sciences, Engineering, and Medicine, argue that e-cigarettes could be an alternative to e-cigarettes for those who are not interested or unable to quit. E-cigarettes reduce the exposure of users to carcinogens and other harmful toxic substances.

Jessica Yingst, assistant professor of public health sciences and Penn State Cancer Institute researcher, and colleagues at Penn State's Center for Tobacco and Health Research study e-cigarettes and whether they can help nicotine users quit or reduce smoking Exposure to harmful toxic substances is found in cigarettes.

Their latest study investigates a common question - whether starting e-cigarettes to cut down on smoking may increase nicotine dependence.

"Research on this topic is conflicting because in previous studies, participants used their own devices, but the nicotine release was unknown," Inster said. "Our study used a device with a known nicotine delivery profile, which allowed us to effectively compare how different levels of nicotine in the device might affect a user's nicotine dependence and ability to reduce cigarette consumption."

The researchers recruited 520 participants who were interested in reducing their cigarette intake but had no smoking cessation program or interest and instructed them to reduce their cigarette consumption during the six-month study period.

Participants were randomized to receive an e-cigarette containing 36, 8 or 0 mg/mL nicotine, or a tobacco-free cigarette alternative to help them reduce cigarette consumption.

Participants self-reported their dependence on cigarettes and e-cigarettes at 1, 3, and 6 months using validated measures of dependence, including a Penn State University-developed questionnaire, ranging from 0 (no dependence at all). ) to 20 (highly dependent). Urine samples were also collected throughout the study to measure cotinine, a biomarker of nicotine exposure.

At six months, all participants in the e-cigarette group reported a significant reduction in cigarette consumption, with participants in the 36 mg/mL group smoking the least number of cigarettes per day. People in the e-cigarette group were significantly less dependent on the Penn State University Cigarette Dependence Index than those in the cigarette-substitute group.

Participants also reported their dependence on e-cigarettes using the Penn State E-Cigarette Dependence Index.

E-cigarette dependence did not change significantly over the course of the study, except that participants in the 36 mg/mL group saw a significant increase in dependence over the course of the study, which remained much lower compared to cigarette dependence.

Urinary cotinine levels remained consistent across all groups during the study period, suggesting that overall exposure to nicotine did not increase during the study period. The results were published in the journal Nicotine and Tobacco Research.

"Our findings suggest that using e-cigarettes or cigarette alternatives to reduce cigarette consumption can reduce self-reported cigarette use and dependence," said Inster, director of the School of Medicine's doctoral program in public health. "Importantly, high-concentration e-cigarette use did not increase overall nicotine dependence compared with cigarette alternatives and was associated with a reduction in smoking."

While it is hypothesized that e-cigarette use may increase overall nicotine dependence, the team said their study found that starting e-cigarette use to reduce cigarette consumption resulted in a reduction in cigarette dependence and a decrease in e-cigarette dependence. In the future, they will assess the health effects of switching entirely from cigarettes to e-cigarettes.

This research was supported by the National Institute on Drug Abuse of the National Institutes of Health and the Center for Tobacco Products of the Food and Drug Administration (grant numbers P50DA036105 and U54DA036105). Data collection was supported by the Penn State Institute for Clinical and Translational Sciences (grant number UL1TR002014) and the C. Kenneth and Dianne Wright Center for Clinical and Translational Research at Virginia Commonwealth University (grant number UL1TR002649) through the National Center for the Advancement of Translational Science Institutes of Health.