title: Paracetamol use in early life and asthma: prospective birth cohort study.
abstract: OBJECTIVE
  To determine if use of paracetamol in early life is an independent risk factor for childhood asthma.
  
  
  METHODS
  Prospective birth cohort study.
  
  
  METHODS
  Melbourne Atopy Cohort Study.
  
  
  METHODS
  620 children with a family history of allergic disease, with paracetamol use prospectively documented on 18 occasions from birth to 2 years of age, followed until age 7 years.
  
  
  METHODS
  The primary outcome was childhood asthma, ascertained by questionnaire at 6 and 7 years. Secondary outcomes were infantile wheeze, allergic rhinitis, eczema, and skin prick test positivity.
  
  
  RESULTS
  Paracetamol had been used in 51% (295/575) of children by 12 weeks of age and in 97% (556/575) by 2 years. Between 6 and 7 years, 80% (495/620) were followed up; 30% (148) had current asthma. Increasing frequency of paracetamol use was weakly associated with increased risk of childhood asthma (crude odds ratio 1.18, 95% confidence interval 1.00 to 1.39, per doubling of days of use). However, after adjustment for frequency of respiratory infections, this association essentially disappeared (odds ratio 1.08, 0.91 to 1.29). Paracetamol use for non-respiratory causes was not associated with asthma (crude odds ratio 0.95, 0.81 to 1.12).
  
  
  CONCLUSIONS
  In children with a family history of allergic diseases, no association was found between early paracetamol use and risk of subsequent allergic disease after adjustment for respiratory infections or when paracetamol use was restricted to non-respiratory tract infections. These findings suggest that early paracetamol use does not increase the risk of asthma.
authors.affiliation: Murdoch Childrens Research Institute, Royal Children's Hospital, Parkville, Vic 3052, Australia. lowe.adrian@gmail.com
authors.forename: Adrian J
authors.initials: AJ
authors.lastname: Lowe
authors.forename: John B
authors.initials: JB
authors.lastname: Carlin
authors.forename: Catherine M
authors.initials: CM
authors.lastname: Bennett
authors.forename: Clifford S
authors.initials: CS
authors.lastname: Hosking
authors.forename: Katrina J
authors.initials: KJ
authors.lastname: Allen
authors.forename: Colin F
authors.initials: CF
authors.lastname: Robertson
authors.forename: Christine
authors.initials: C
authors.lastname: Axelrad
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Abramson
authors.forename: David J
authors.initials: DJ
authors.lastname: Hill
authors.forename: Shyamali C
authors.initials: SC
authors.lastname: Dharmage
mesh_terms: D000082:Acetaminophen / Q000009:adverse effects*; D018712:Analgesics, Non-Narcotic / Q000009:adverse effects*; D001249:Asthma / Q000139:chemically induced* / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D004485:Eczema / Q000139:chemically induced / Q000453:epidemiology; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D011446:Prospective Studies; D012221:Rhinitis, Allergic, Perennial / Q000139:chemically induced / Q000453:epidemiology; D012307:Risk Factors; D014739:Victoria / Q000453:epidemiology
chemical_list: D018712:Analgesics, Non-Narcotic; D000082:Acetaminophen