title: Prevalence of secondhand smoke exposure in asthmatic children at home and in the car: A cross-sectional study.
abstract: OBJECTIVE
  To compare secondhand smoke exposure (SHSe) prevalence at home and inside the car between asthmatic and non-asthmatic Portuguese children.
  
  
  METHODS
  This is a cross-sectional study that assessed children's SHSe in a representative sample of nine Portuguese cities. A validated self-reported questionnaire was administered to a random sample of 4th grade students during the school year of 2010/2011. The asthma prevalence was defined by the answers to three questions regarding asthma symptoms, medication and inhaler use. We performed chi-square tests and analysed frequencies, contingency tables, confidence intervals, and odd-ratios.
  
  
  RESULTS
  The self-reported questionnaire was administered to 3187 students. Asthma prevalence was 14.8% (472 students). Results showed that 32.3% of non-asthmatic children and 32.4% of asthmatic children were exposed to secondhand smoke as at least one of their household members smoked at home. The prevalence of parental smoking, smoking among fathers and smoking among mothers at home was also similar in both groups (asthmatic and non-asthmatic children). SHSe inside the car was 18.6% among non-asthmatic children and 17.9% among asthmatic children.
  
  
  CONCLUSIONS
  Asthmatic and non-asthmatic children were equally exposed to secondhand smoke, because no significant differences were found between the two groups concerning the prevalence of SHSe at home and inside the car. These findings highlight the need to include SHSe brief advice in paediatric asthma management.
authors.affiliation: Pediatric Department, Hospital de Braga, Braga, Portugal.
authors.forename: H
authors.initials: H
authors.lastname: Antunes
authors.affiliation: Institute of Education, University of Minho, Braga, Portugal. Electronic address: precioso@ie.uminho.pt.
authors.forename: J
authors.initials: J
authors.lastname: Precioso
authors.affiliation: Institute of Education, University of Minho, Braga, Portugal.
authors.forename: A C
authors.initials: AC
authors.lastname: Araújo
authors.affiliation: Institute of Social Sciences, University of Minho, Braga, Portugal.
authors.forename: J C
authors.initials: JC
authors.lastname: Machado
authors.affiliation: EPIUnit - Institute of Public Health, University of Porto, Porto, Portugal.
authors.forename: C
authors.initials: C
authors.lastname: Samorinha
authors.affiliation: Faculty of Psychology and Educational Sciences, University of Porto, Porto, Portugal.
authors.forename: V
authors.initials: V
authors.lastname: Rocha
authors.affiliation: Immunoallergy Department, CUF-Descobertas Hospital, Lisbon, Portugal.
authors.forename: Â
authors.initials: Â
authors.lastname: Gaspar
authors.affiliation: Unidade de Tabaquismo, Santiago de Compostela University, Spain.
authors.forename: E
authors.initials: E
authors.lastname: Becoña
authors.affiliation: Preventive Medicine, Faculty of Health Sciences, Beira Interior University, Covilhã, Portugal.
authors.forename: S
authors.initials: S
authors.lastname: Belo-Ravara
authors.affiliation: Preventive Medicine, Faculty of Health Sciences, Beira Interior University, Covilhã, Portugal.
authors.forename: P
authors.initials: P
authors.lastname: Vitória
authors.affiliation: Division of Health Promotion, Town Hall, Viana do Castelo, Portugal.
authors.forename: M
authors.initials: M
authors.lastname: Rosas
authors.affiliation: Catalan Oncology Institute, Barcelona, Spain.
authors.forename: E
authors.initials: E
authors.lastname: Fernandez
mesh_terms: D000293:Adolescent; D016902:Air Pollution, Indoor / Q000706:statistics & numerical data*; D001249:Asthma / Q000453:epidemiology; D001336:Automobiles; D002648:Child; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D011174:Portugal; D012111:Residence Characteristics; D057566:Self Report; D014028:Tobacco Smoke Pollution / Q000706:statistics & numerical data*
chemical_list: D014028:Tobacco Smoke Pollution
keywords: Asthma; Children; Secondhand smoke