title: Association between Household Income and Asthma Symptoms among Elementary School Children in Seoul.
abstract: OBJECTIVE
  This study examined the association between socioeconomic factors and asthma symptoms.
  
  
  METHODS
  A total of 6,919 elementary school children in Seoul were enrolled in the study. Data were obtained from a web-based questionnaire survey. The questionnaire was based on the International Study of Asthma and Allergies in Childhood core module. The prevalence of wheeze in the past 12 months and severe asthma symptoms were obtained. The potential risk factors for asthma symptoms included household income and the number of siblings. A multiple logistic regression analysis was used to calculate the odds ratios (OR) and 95% confidence interval (CI) for the risk factors of asthma symptoms.
  
  
  RESULTS
  The prevalence of current wheeze (wheeze in the past 12 months) was 5.2%. Household income and asthma symptoms were inversely associated after adjusting for other potential risk factors (p for trend=0.03). This association was modified by the number of siblings. With two or more siblings, the effect of household income on asthma symptoms was not significant. However, low household income was still a significant variable for patients with fewer than two siblings (OR 1.41; 95% CI, 1.09-1.81).
  
  
  CONCLUSIONS
  It appears that childhood asthma disparity is dependent on household income. Therefore, policies to improve childhood health inequities should be emphasized.
authors.affiliation: Department of Occupational and Environmental Medicine, Gachon University Gil Medical Center, Incheon, Korea.
authors.forename: Won-Jun
authors.initials: WJ
authors.lastname: Choi
authors.forename: In-Yong
authors.initials: IY
authors.lastname: Um
authors.forename: Soyoung
authors.initials: S
authors.lastname: Hong
authors.forename: Hye Yung
authors.initials: HY
authors.lastname: Yum
authors.forename: Hyunjung
authors.initials: H
authors.lastname: Kim
authors.forename: Hojang
authors.initials: H
authors.lastname: Kwon