title: Prenatal paracetamol exposure and risk of wheeze at preschool age.
abstract: OBJECTIVE
  To analyse the association between prenatal paracetamol exposure and preschool wheeze.
  
  
  METHODS
  Data were obtained from a prospective, longitudinal study of a cohort of children born in the region of western Sweden in 2003; 8176 families were randomly selected. The parents answered questionnaires at 6 and 12 months and at 4.5 years of age. The response rate was 55%, i.e. 4496 of the 5398 questionnaires distributed at 4.5 years (83%). Inhaled corticosteroid (ICS) treated wheeze during the last year was regarded as a proxy for doctor-diagnosed asthma. Episodic viral wheeze was defined as wheezing only with viral infections and multiple-trigger wheeze as wheezing also in between infections.
  
  
  RESULTS
  In the multivariate analysis, the risk of ICS-treated wheeze was increased by paracetamol (OR 1.6; 95% CI 1.01-2.6). Within the ICS-treated group, the effect was significant for multiple-trigger wheeze (OR 2.4; 1.2-4.8) but not for episodic viral wheeze (OR 1.1; 0.5-2.3).
  
  
  CONCLUSIONS
  Prenatal paracetamol exposure was an independent risk factor for ICS-treated wheeze at preschool age, especially among children with ICS-treated multiple-trigger wheeze. Although the analysis adjusted for e.g. maternal asthma and antibiotic use, the possibility of residual confounding by maternal indication (respiratory illness) should be acknowledged.
authors.affiliation: Department of Paediatrics, University of Gothenburg, Queen Silvia Children's Hospital, Gothenburg, Sweden. emma.goksor@vgregion.se
authors.forename: Emma
authors.initials: E
authors.lastname: Goksör
authors.forename: Hrefna
authors.initials: H
authors.lastname: Thengilsdottir
authors.forename: Bernt
authors.initials: B
authors.lastname: Alm
authors.forename: Gunnar
authors.initials: G
authors.lastname: Norvenius
authors.forename: Göran
authors.initials: G
authors.lastname: Wennergren
mesh_terms: D000082:Acetaminophen / Q000009:adverse effects*; D000280:Administration, Inhalation; D000305:Adrenal Cortex Hormones / Q000008:administration & dosage* / Q000627:therapeutic use; D002675:Child, Preschool; D005260:Female; D006801:Humans; D015999:Multivariate Analysis; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D011446:Prospective Studies; D012135:Respiratory Sounds / Q000187:drug effects / Q000209:etiology*; D013548:Sweden
chemical_list: D000305:Adrenal Cortex Hormones; D000082:Acetaminophen