title: Allergens, air pollutants, and childhood allergic diseases.
abstract: BACKGROUND
  The synergistic effect of allergens and air pollutants on the risk of allergic diseases is unclear.
  
  
  OBJECTIVE
  To evaluate the joint effect of outdoor pollutants and indoor allergens on the risk of allergic diseases.
  
  
  METHODS
  We enrolled 2661 kindergarten children from the CEAS cohort. Data on allergic diseases and environmental exposure were collected. Skin prick tests were performed. Individual exposure to air pollution was estimated using a geographic information system with the mean concentration of air pollutants. Multiple logistic regression analysis was performed to estimate the association between air pollutants, allergen exposure and the risk of allergic diseases with adjustments for potential confounders.
  
  
  RESULTS
  Overall, 12.6% of the children had asthma, 30.0% had allergic rhinitis (AR), and 14.4% had atopic dermatitis (AD). Mite sensitization significantly increased the risk of AD, AR, and asthma (OR (95%CI) 2.15 (1.53-3.03), 1.94 (1.46-2.58), and 2.31 (1.63-3.29), respectively). Exposure to PM10, PM(2.5), CO, and O(3) was associated with asthma (OR (95% CI) 1.39 (1.03-1.87), 1.45 (1.07-1.97), 1.36 (1.01-1.83), and 0.68 (0.51-0.92), respectively). PM(2.5) may have increased the risk of AR (OR (95% CI) 1.54 (1.03-2.32). Mite sensitization showed a synergistic effect with PM(2.5) on the development of asthma (p < 0.001). Moreover, mite allergens may modify the effect of air pollutants on allergic diseases.
  
  
  CONCLUSIONS
  Dust mites and PM(2.5) play an important role on the risk of asthma and AR. Exposure to PM(2.5) and mite allergens had a synergistic effect on the development of asthma. Avoiding co-exposure to allergens and air pollutants is important.
authors.affiliation: Department of Pediatrics, Taipei Hospital, Ministry of Health and Welfare, Taipei, Taiwan; Institute of Environmental and Occupational Health Sciences, College of Medicine, National Yang-Ming University, Taipei, Taiwan; Department of Health Risk Management, China Medical University, Taichung, Taiwan. Electronic address: wij636@gmail.com.
authors.forename: I-Jen
authors.initials: IJ
authors.lastname: Wang
authors.affiliation: College of Public Health, Fu Jen Catholic University, Taipei, Taiwan; Department of Medical Research and Education, Cheng-Hsin General Hospital, Taiwan.
authors.forename: Tao-Hsin
authors.initials: TH
authors.lastname: Tung
authors.affiliation: College of Public Health, Fu Jen Catholic University, Taipei, Taiwan.
authors.forename: Chin-Sheng
authors.initials: CS
authors.lastname: Tang
authors.affiliation: College of Public Health, Fu Jen Catholic University, Taipei, Taiwan.
authors.forename: Zi-Hao
authors.initials: ZH
authors.lastname: Zhao
mesh_terms: D000393:Air Pollutants / Q000009:adverse effects* / Q000276:immunology; D000397:Air Pollution / Q000009:adverse effects; D000485:Allergens / Q000009:adverse effects* / Q000276:immunology; D000818:Animals; D001249:Asthma / Q000453:epidemiology / Q000209:etiology*; D002248:Carbon Monoxide / Q000009:adverse effects / Q000276:immunology; D002648:Child; D002675:Child, Preschool; D003876:Dermatitis, Atopic / Q000453:epidemiology / Q000209:etiology; D004391:Dust; D004781:Environmental Exposure / Q000009:adverse effects*; D005260:Female; D006801:Humans; D008297:Male; D010126:Ozone / Q000009:adverse effects / Q000276:immunology; D052638:Particulate Matter / Q000009:adverse effects* / Q000276:immunology; D039981:Pyroglyphidae; D065631:Rhinitis, Allergic / Q000453:epidemiology / Q000209:etiology*
chemical_list: D000393:Air Pollutants; D000485:Allergens; D004391:Dust; D052638:Particulate Matter; D010126:Ozone; D002248:Carbon Monoxide
keywords: Air pollutant; Allergen; Asthma