title: Early-life house dust mite allergens, childhood mite sensitization, and respiratory outcomes.
abstract: BACKGROUND
  Exposure to indoor allergens during early life may play a role in the development of the immune system and inception of asthma.
  
  
  OBJECTIVE
  To describe the house dust mite (HDM) allergen concentrations in bedroom dust during early life and to evaluate its associations with HDM sensitization, wheezing, and asthma, from birth to school age, in 5 geographically spread European birth cohorts.
  
  
  METHODS
  We included 4334 children from INMA-Menorca (Spain), BAMSE (Sweden), LISAplus and MAS (Germany), and PIAMA-NHS (the Netherlands). Dust samples were collected from bedrooms during early life and analyzed for Dermatophagoides pteronyssinus (Der p1) and Dermatophagoides farinae (Der f1). HDM concentrations were divided into four categories. Sensitization was determined by specific IgE. Wheezing and asthma information up to 8/10 years was collected through questionnaires. We performed mixed-effects logistic regression models and expressed associations as odds ratios with 95% confidence intervals.
  
  
  RESULTS
  House dust mite concentrations varied across cohorts. Mean allergen concentrations were highest in INMA-Menorca (geometric mean (GM) Der p1 = 3.3 μg/g) and LISAplus (GM Der f1 = 2.1 μg/g) and lowest in BAMSE (GM Der p1 = 0.1 μg/g, Der f1 = 0.3 μg/g). Moderate and high HDM concentrations were significantly (P-values < 0.05) associated with 50-90% higher prevalence of HDM sensitization. No significant associations were observed with respiratory outcomes.
  
  
  CONCLUSIONS
  Our study based on geographically spread regions, a large sample size, and a wide range of allergen concentration shows that HDM allergen concentrations vary across regions and that exposure during early life plays a role in the development of allergic sensitization but not in the development of respiratory outcomes.
authors: Department of Public Health and Primary Care, Centre for Environment and Health, KU Leuven, Leuven, Belgium.|Centre for Research in Environmental Epidemiology (CREAL), Barcelona, Spain.|CIBER Epidemiologia y Salud Pública (CIBERESP), Barcelona, Spain.
authors: L
authors: L
authors: Casas
authors: Centre for Research in Environmental Epidemiology (CREAL), Barcelona, Spain.|CIBER Epidemiologia y Salud Pública (CIBERESP), Barcelona, Spain.|Hospital del Mar Medical Research Institute (IMIM), Barcelona, Spain.|Universitat Pompeu Fabra (UPF), Barcelona, Spain.
authors: J
authors: J
authors: Sunyer
authors: Helmholtz Zentrum München, German Research Centre for Environmental Health, Institute of Epidemiology I, Neuherberg, Germany.
authors: C
authors: C
authors: Tischer
authors: Division of Environmental Epidemiology, Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands.
authors: U
authors: U
authors: Gehring
authors: Department of Clinical Science and Education, Södersjukhuset, Karolinska Institutet, Stockholm, Sweden.|Sach's Children's Hospital, Stockholm, Sweden.|Institute for Environmental Medicine, Karolinska Institutet, Stockholm, Sweden.
authors: M
authors: M
authors: Wickman
authors: Centre for Research in Environmental Epidemiology (CREAL), Barcelona, Spain.|CIBER Epidemiologia y Salud Pública (CIBERESP), Barcelona, Spain.|Hospital del Mar Medical Research Institute (IMIM), Barcelona, Spain.
authors: R
authors: R
authors: Garcia-Esteban
authors: Department of Environmental Immunology, FZ-Helmholtz Centre for Environmental Research Leipzig, Leipzig, Germany.
authors: I
authors: I
authors: Lehmann
authors: Department of Clinical Science and Education, Södersjukhuset, Karolinska Institutet, Stockholm, Sweden.|Sach's Children's Hospital, Stockholm, Sweden.|Institute for Environmental Medicine, Karolinska Institutet, Stockholm, Sweden.
authors: I
authors: I
authors: Kull
authors: Institute of Social Medicine, Epidemiology and Health Economics, Charité - Universitätsmedizin Berlin, Berlin, Germany.
authors: A
authors: A
authors: Reich
authors: Klinik für Pädiatrie m. S. Pneumologie und Immunologie, Charité - Universitätsmedizin Berlin, Berlin, Germany.
authors: S
authors: S
authors: Lau
authors: Centre for Nutrition, Prevention and Health Services, National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands.
authors: A
authors: A
authors: Wijga
authors: Centre for Research in Environmental Epidemiology (CREAL), Barcelona, Spain.|CIBER Epidemiologia y Salud Pública (CIBERESP), Barcelona, Spain.|Hospital del Mar Medical Research Institute (IMIM), Barcelona, Spain.|Universitat Pompeu Fabra (UPF), Barcelona, Spain.
authors: J M
authors: JM
authors: Antó
authors: Department of Public Health and Primary Care, Centre for Environment and Health, KU Leuven, Leuven, Belgium.|Centre for Environmental Sciences, Hasselt University, Hasselt, Belgium.
authors: T S
authors: TS
authors: Nawrot
authors: Helmholtz Zentrum München, German Research Centre for Environmental Health, Institute of Epidemiology I, Neuherberg, Germany.|Comprehensive Pneumology Center Munich (CPC-M), German Center for Lung Research (DZL), Munich, Germany.
authors: J
authors: J
authors: Heinrich
authors: Institute of Social Medicine, Epidemiology and Health Economics, Charité - Universitätsmedizin Berlin, Berlin, Germany.|Institute of Clinical Epidemiology and Biometry, University of Wuerzburg, Wuerzburg, Germany.
authors: T
authors: T
authors: Keil
authors: Area de Salud de Menorca, IB-SALUT, Menorca, Spain.
authors: M
authors: M
authors: Torrent
mesh_terms: D000293:Adolescent; D000367:Age Factors; D000485:Allergens / Q000276:immunology*; D000818:Animals; D039741:Antigens, Dermatophagoides / Q000276:immunology*; D001249:Asthma / Q000453:epidemiology / Q000276:immunology; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D005060:Europe / Q000453:epidemiology; D005260:Female; D006801:Humans; D006967:Hypersensitivity / Q000453:epidemiology* / Q000276:immunology*; D007223:Infant; D008297:Male; D016017:Odds Ratio; D063868:Patient Outcome Assessment; D039981:Pyroglyphidae / Q000276:immunology*; D012135:Respiratory Sounds / Q000276:immunology
chemical_list: D000485:Allergens; D039741:Antigens, Dermatophagoides
keywords: allergens and epitopes; epidemiology; pediatrics