Exclusive versus dual use of tobacco and electronic cigarettes among adolescents in Poland, 2010-2016.

Globally, electronic cigarette (e-cigarette) use among adolescents has increased, along with concerns about potential health implications from exclusive and concurrent tobacco and e-cigarette use (i.e., "dual use"). This study used data from a cross-sectional survey administered to 5708 students aged 15-19 in secondary and technical schools throughout two regions of Poland. Data from 2010-2011 (n = 1760); 2013-2014 (n = 1970) and 2015-2016 (n = 1978) were analyzed to assess changes in use of cigarettes and e-cigarettes from 2010-2016, and correlates of exclusive and dual use, daily use, and intensity of product use from 2013-2016. In this sample, e-cigarette trial and past 30-day exclusive e-cigarette use significantly increased over time (2010-2011: 2%; 2013-2014: 8%; 2015-2016: 11% (p < .05)). Dual use increased from 2010-2011 (4%) to 2013-2014 only (23%, p < .05); and remained stable from 2013-2014 to 2015-2016 (24%, p = .60). Most dual users reported using cigarettes before trying e-cigarettes (82% in 2013-2014, 76% in 2015-2016). Analyses comparing dual users to exclusive users showed significant differences in frequency and intensity of product use, similar findings were observed within dual users. Following the introduction of e-cigarettes, both total tobacco use and total cigarette use increased. Among youth in Poland, e-cigarettes do not seem to replace conventional cigarettes, but instead contribute to a more diverse array of available products from which youth can experiment.