Disparities and Trends in Indoor Exposure to Secondhand Smoke

Introduction: Secondhand smoke (SHS) exposure causes disease and death among nonsmokers. With a plethora of smokefree legislation implemented and a steady decrease in cigarette consumption noted over the past decade in the U.S., this study assessed trends in indoor SHS exposure among U.S. adolescents in grades 6–12 during 2000–2009. Methods: Data were obtained from the 2000–2009 National Youth Tobacco Survey – a national survey of U.S. middle and high school students. SHS exposure within an indoor area within the past seven days was self-reported. Trends in indoor SHS exposure during 2000–2009 were assessed overall and by socio-demographic characteristics, using the Wald’s test in a binary logistic regression. Within-group comparisons were performed using chi-squared statistics (p,0.05). Results: The proportion of U.S. middle and high school students who were exposed to indoor SHS declined from 65.5% in 2000 to 40.5% in 2009 (p,0.05 for linear trend). Significant declines were also observed across all population subgroups. Between 2000 and 2009, prevalence of indoor SHS exposure declined significantly among both middle (58.5% to 34.3%) and high school (71.5% to 45.4%) students. Prevalence of indoor SHS exposure was significantly higher among girls (44.0% in 2009) compared to boys (37.2% in 2009) during each survey year. Similarly, prevalence of indoor SHS exposure during 2000– 2009 was highest among non-Hispanic whites (44.2% in 2009) and lowest among non-Hispanic Asians (30.2% in 2009). During each survey year, prevalence was highest among the oldest age group ($18 years) and lowest among the youngest (9–11 years). Also, prevalence was significantly higher among current cigarette smokers (83.8% in 2009) compared to nonsmokers (34.0% in 2009). Conclusion: Significant declines in indoor SHS exposure among U.S. middle and high school students occurred during 2000–2009. While the results are encouraging, additional efforts are needed to further reduce youth indoor SHS exposure. Citation: Agaku IT, Vardavas CI (2013) Disparities and Trends in Indoor Exposure to Secondhand Smoke among U.S. Adolescents: 2000-2009. PLoS ONE 8(12): e83058. doi:10.1371/journal.pone.0083058 Editor: Homayoun Shams, University of Texas at Tyler, United States of America Received May 13, 2013; Accepted October 30, 2013; Published December 17, 2013 Copyright: 2013 Agaku, Vardavas. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Funding: The authors have no support or funding to report. Competing Interests: The authors have declared that no competing interests exist. * E-mail: [email protected]