title: Allergen exposure in infancy and the development of sensitization, wheeze, and asthma at 4 years.
abstract: BACKGROUND
  The relationship between mite and pet allergen exposure in infancy and the subsequent development of sensitization and asthma is complex.
  
  
  OBJECTIVE
  We prospectively investigated the effect of allergen exposure at 3 months of age on the development of sensitization, wheeze, and physician-diagnosed asthma in the first 4 years of life in a birth cohort of children with and without an atopic mother.
  
  
  METHODS
  Children participated in the Prevention and Incidence of Asthma and Mite Allergy study. Allergen exposure at 3 months of age was determined from mattress dust samples. Specific IgE to inhalant allergens was measured at 4 years of age, and information about wheeze and physician-diagnosed asthma was collected with yearly questionnaires.
  
  
  RESULTS
  Mite and cat allergen exposure in infancy were associated with an increased risk of specific sensitization to house dust mite and cat, respectively, at 4 years of age. There were borderline significant associations between cat allergen exposure and persistent wheeze in the total study population and between dog allergen exposure and persistent wheeze in children with a nonatopic mother. In children with an atopic mother, there was some indication of a positive association between mite allergen exposure and physician-diagnosed asthma.
  
  
  CONCLUSIONS
  Early house dust mite and cat allergen exposure might lead to sensitization and, in case of cat allergen exposure, to persistent wheeze. Early mite and dog allergen exposure might lead to asthma and persistent wheeze, respectively, but only in subgroups defined by maternal atopy.
authors.affiliation: Center for Prevention and Health Services Research, National Institute for Public Health and Environment, Bilthoven, the Netherlands.
authors.forename: Jessica E
authors.initials: JE
authors.lastname: Brussee
authors.forename: Henriette A
authors.initials: HA
authors.lastname: Smit
authors.forename: Robert T
authors.initials: RT
authors.lastname: van Strien
authors.forename: Karen
authors.initials: K
authors.lastname: Corver
authors.forename: Marjan
authors.initials: M
authors.lastname: Kerkhof
authors.forename: Alet H
authors.initials: AH
authors.lastname: Wijga
authors.forename: Rob C
authors.initials: RC
authors.lastname: Aalberse
authors.forename: Dirkje
authors.initials: D
authors.lastname: Postma
authors.forename: Jorrit
authors.initials: J
authors.lastname: Gerritsen
authors.forename: Diederick E
authors.initials: DE
authors.lastname: Grobbee
authors.forename: Johan C
authors.initials: JC
authors.lastname: de Jongste
authors.forename: Bert
authors.initials: B
authors.lastname: Brunekreef
mesh_terms: D000328:Adult; D000485:Allergens / Q000009:adverse effects*; D000818:Animals; D001249:Asthma / Q000097:blood / Q000235:genetics / Q000517:prevention & control*; D002415:Cats; D002675:Child, Preschool; D015331:Cohort Studies; D004285:Dogs; D004391:Dust / Q000276:immunology*; D005260:Female; D006801:Humans; D007114:Immunization; D007073:Immunoglobulin E / Q000097:blood; D007223:Infant; D019570:Inhalation Exposure / Q000009:adverse effects*; D008297:Male; D008925:Mites; D009426:Netherlands; D016017:Odds Ratio; D012135:Respiratory Sounds / Q000209:etiology; D012307:Risk Factors; D011795:Surveys and Questionnaires
chemical_list: D000485:Allergens; D004391:Dust; D007073:Immunoglobulin E