1. Sarah Kowitt, MPH 1 ; Li-Ling Huang, PhD, MPH 2 ; Tanha Patel, MPH 3 ; Leah Ranney, PhD 4 ; Erin L. Sutfin, PhD 5 ; Adam O. Goldstein, MD, MPH 4 E-Cigarette Use Among High School Students in North Carolina: An Emerging Public Health Issue BackgroundResults Dataset: 2011 and 2013 NC Youth Tobacco Survey (NCYTS), public and charter school-based surveys Sampling: Two-stage cluster design with corresponding sampling weights to produce representative data of HS students Sample size: 2011: n = 4,791 (response rate: 78.2% ) 2013: n = 4,092 (response rate: 67.8%) Measurement: Ever e-cigarette user: ever tried e-cigarettes, even 1 or 2 puffs. Current e-cigarette user: used an e-cig > 1 day in last 30 days. Considering e-cigarette user*: consider using e-cig in next year. Analysis: Bivariate/multivariate regression to examine associations between e-cig and cigarette use in 2011 & 2013. Methods Limitations 1. University of North Carolina at Chapel Hill, Gillings School of Global Public Health; 2. University of North Carolina at Chapel Hill, Lineberger Comprehensive Cancer Center; 3. North Carolina Department of Health and Human Services, Tobacco Prevention and Control Branch; 4. University of North Carolina at Chapel Hill, Department of Family Medicine; 5. Wake Forest School of Medicine, Department of Social Sciences and Health Policy. Electronic cigarettes (e-cigs), use is rising among youth. 1-3 E-cigarette companies heavily advertise their products and use characterizing flavors that appeal to youth. 4 Little research has been conducted on changes in e- cigarette use over time among youth and associations with cigarette use. The study assesses patterns and trends of e-cig use among high school (HS) students in North Carolina (NC). *Considering e-cigarette use was not measured in 2011. **Covariates in the regression models are race, sex and grade. ***Smoking intensity was measured by a question: During past 30 days, on the days you smoked, how many cigarettes did you smoker per day. Abbreviation: OR= odds ratio, AOR= adjusted odds ratio, CI= confidence interval, Coef.= coefficient. Red bars in Figure 1 and Figure 2 represent 95% confidence intervals. Although youth cigarette use is declining, e-cigarette use is becoming widespread and increasing among HS students, presenting a challenge for the public health community. More high school nonsmokers reported that they ever or currently used e-cigarette in 2013 than 2011, suggesting e-cigarettes are a possible introduction to nicotine among high school nonsmokers. Almost one-fifth of the NC high school nonsmoker population is considering e-cigarette use, suggesting a possible increase in e- cigarette use among youth. Future research should investigate motivation and influences (e.g., popularity, product appeal, advertising, perceived health risk, smoking cessation, and other social and contextual factors) for using e-cigarettes among tobacco nonusers and users. Causality is difficult to conclude from a cross-sectional survey. The findings are subject to self-reported, recall biases and social desirability. Results may not generalize to youth in other populations other than NC high school students; however, results are similar to national results for high school students. 1-2 Figure 1. Prevalence of E-cigarette and Cigarette Use in 2011 and 2013 The significant rise of e-cigarette use among nonsmoking youth is a major public health concern. Increases in e-cigarette use among high school youth far exceed any declines in current cigarette use. More effort needs to be made to understand motivation and influence of e-cigarette use among youth, including strategies to prevent marketing and sales to youth. Positive associations between cigarette smoking intensity and e- cigarette use, along with increasing dual current use of cigarette and e-cigarette use among youth need additional research. Discussions Results Figure 2. E-cigarette Use and Cigarette Smoking in 2011 and 2013 Funding: Research reported in this publication was supported by Office Of The Director, National Institutes of Health (OD) and FDA Center for Tobacco Products (CTP). The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH or the Food and Drug Administration. The NCYTS was administered with support from the Centers for Disease Control and Prevention Grant or Cooperative Agreement Number, DP 14-1415. Reference: 1. Chapman, S. L. C., & Wu, L. T. (2014). E-cigarette prevalence and correlates of use among adolescents versus adults: A review, and comparison. Journal of Psychiatric Research, 54, 43-54. doi: DOI 10.1016/j.jpsychires.2014.03.005. 2. Dutra, L. M., & Glantz, S. A. (2014). Electronic Cigarettes and Conventional Cigarette Use Among US Adolescents A Cross-sectional Study. Jama Pediatrics, 168(7), 610-617. doi: DOI 10.1001/jamapediatrics.2013.5488. 3. Corey, C., Wang, B. G., Johnson, S. E., Apelberg, B., Husten, C., King, B. A.,... Dube, S. R. (2013). Electronic Cigarette Use Among Middle and High School Students - United States, 2011-2012. Mmwr-Morbidity and Mortality Weekly Report, 62(35), 729-730. 4. Grana, R. A., & Ling, P. M. (2014). "Smoking Revolution" A Content Analysis of Electronic Cigarette Retail Websites. American Journal of Preventive Medicine, 46(4), 395-403. doi: DOI 10.1016/j.amepre.2013.12.010. Conflicts of Interest: None. Current cigarette users were more likely to use e-cigarettes currently than cigarette ever users (OR=4.50, 95% CI, 3.35-6.03; AOR**=4.28, 95% CI, 3.16-5.79 in 2013). E-cigarette current use was associated with heavier cigarette smoking*** (Coef.=1.5, p<.001 in 2013; Coef.=2.4, p<.001 in 2011). Among all HS students in 2013, 20.1% (95% CI: 15.9%- 24.3%) reported that they had ever tried e-cigarettes, were currently using e-cigarettes, or were considering e-cigarettes in the next year. E-cigarette current use among NC HS students increased by about five times over the past two years (Figure 1). Among current e-cigarette users in 2013, prevalence was highest among males (10.9%, 95% CI: 7.3%-14.5%), those in 12 th grade (10.8%), and White students (11.2%, 95% CI: 7.7%- 14.6%). Conclusions