US prevalence and trends in tobacco smoke exposure among children and adolescents with asthma.

To examine exposure to tobacco smoke products (TSPs), environmental tobacco smoke (ETS), and in-home smoke among youth with asthma in the United States. Nationally representative, cross-sectional data from 2250 youth aged 4 to 19 years with current asthma in the 1988-1994, 1999-2004, and 2005-2010 National Health and Nutrition Examination Survey (NHANES) were analyzed. Outcomes were use of TSPs (serum cotinine level >10 ng/mL or self-reported recent use of cigarettes, cigars, or pipes) and, among non-TSP users, ETS exposure (serum cotinine ≥0.05 ng/mL) and in-home smoke exposure (reported). Multiple logistic regression analyses assessed the associations between the outcomes and age, gender, race/ethnicity, and family income. Among adolescents (aged 12-19 years) with asthma in 2005-2010, 17.3% reported TSP use. Among youth (aged 4-19 years) with asthma who did not use TSPs, 53.2% were exposed to ETS and 17.6% had in-home smoke exposure. Among low-income youth, 70.1% and 28.1% had exposure to ETS and in-home smoke, respectively. After controlling for sociodemographic factors, higher prevalence of exposure to ETS and in-home smoke persisted among low-income youth. Between 1988-1994 and 2005-2010, there was a decline in ETS and in-home smoke exposure (both P < .001). ETS exposure among youth with asthma declined between 1988-1994 and 2005-2010, but a majority remained exposed in 2005-2010, with higher exposure among low-income youth. More than 1 in 6 youth with asthma in 2005-2010 were exposed to in-home smoke and a similar portion of adolescents used TSPs.