Racial Differences in the Effects of Postnatal Environmental Tobacco Smoke on Neurodevelopment WHAT’S KNOWN ON THIS SUBJECT: Environmental exposures, including prenatal smoking exposure, are significantly associated with ADHD. However, the association between postnatal ETS exposure and ADHD remains unclear. WHAT THIS STUDY ADDS: This study assessed the association between postnatal ETS exposure and ADHD, independent of prenatal ETS exposure, in a large, nationally representative sample of US children and examined whether there was an interaction between race and postnatal ETS exposure. abstract OBJECTIVES: We used the 2001–2004 National Health and Nutrition Examination Survey to examine the association between postnatal en- vironmental tobacco smoke exposure, measured as serum cotinine levels, and attention-deficit/hyperactivity disorder (ADHD) among chil- dren 4 to 15 years of age. We further investigated the interactions of race and serum cotinine levels with ADHD. METHODS: Logistic regression models were used to evaluate associations. RESULTS: This study found that the prevalence of ADHD increased as blood cotinine levels increased. The effects of blood cotinine levels on ADHD differed according to race. Compared with children of the same racial group with the lowest blood cotinine levels, the odds ratios were 2.72 (95% confidence interval: 1.25–5.93) for Mexican American chil- dren and 5.32 (95% confidence interval: 1.55–18.3) for children in other racial groups with the highest blood cotinine levels, with controlling for the effect of maternal smoking during pregnancy. However, no signifi- cant associations between blood cotinine levels and ADHD were ob- served among non-Hispanic white or non-Hispanic black children. CONCLUSIONS: The findings of this study underscore the possibility of racial disparities in the effects of environmental tobacco smoke on behavioral problems in children. These findings warrant further investigation. Pediatrics 2010;126:705–711 AUTHORS: Xiaohui Xu, PhD, a Robert L. Cook, MD, a Vito A. Ilacqua, PhD, b Haidong Kan, PhD, c and Evelyn O. Talbott, DrPH d Departments of a Epidemiology and Biostatistics and b Environmental and Global Health, College of Public Health and Health Professions, University of Florida, Gainesville, Florida; c Department of Environmental Health, School of Public Health, Fudan University, Shanghai, China; and d Department of Epidemiology, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, Pennsylvania KEY WORDS cotinine, attention-deficit/hyperactivity disorder, National Health and Nutrition Examination Survey, smoking, environmental exposure ABBREVIATIONS ADHD—attention-deficit/hyperactivity disorder CI—confidence interval ETS—environmental tobacco smoke NHANES—National Health and Nutrition Examination Survey OR—odds ratio www.pediatrics.org/cgi/doi/10.1542/peds.2009-3589 doi:10.1542/peds.2009-3589 Accepted for publication Jun 4, 2010 Address correspondence to Xiaohui Xu, PhD, University of Florida, College of Public Health and Health Professions, Department of Epidemiology and Biostatistics, 101 S. Newell Dr, Room 3116, Gainesville, FL 32610-0182. E-mail: xhxu@phhp.ufl. edu PEDIATRICS (ISSN Numbers: Print, 0031-4005; Online, 1098-4275). Copyright © 2010 by the American Academy of Pediatrics FINANCIAL DISCLOSURE: The authors have indicated they have no financial relationships relevant to this article to disclose. ARTICLE PEDIATRICS Volume 126, Number 4, October 2010 705 by guest on October 10, 2021 www.aappublications.org/news Downloaded from