Asthma, indoor and outdoor air pollution: A pilot study in Lebanese school teenagers

Introduction. - Many studies have demonstrated that outdoor pollution might exacerbate respiratory symptoms and childhood asthma. Our objective was to evaluate the relationship between asthma and outdoor and indoor pollution. Methods. - We undertook a survey in May-June 2012 about schoolchildren aged 12-19 years in six Lebanese schools. This combined the International Study of Asthma and Allergies in Childhood (ISAAC) standardized questionnaire with other questions addressing outdoor and indoor exposure. Results. - Among 717 subjects (response rate 71.7%), 4.5% had physician-diagnosed asthma, 34.7% had probable asthma and 60.8% were asymptomatic. Exposure to indoor contaminants was positively associated to asthma. The risk for asthma was higher in those residing near heavy road traffic (ORa =4.30 [95% CI 1.45-12.71], P < 0.05), those previously exposed to fire (ORa = 1.84 [95% CI 1.01-3.36]), and those exposed to smog (ORa =4.15 [95% CI 1.42-12.12]). Airing the house in the morning or in case of indoor smoking had a protective effect against asthma. Conclusion. - These results suggest that the risks of asthma or having respiratory symptoms are not only related to indoor pollution but also to outdoor pollution especially from road traffic. (C) 2015 SPLF. Published by Elsevier Masson SAS. All rights reserved.