title: Respiratory distress syndrome in moderately late and late preterm infants and risk of cerebral palsy: a population-based cohort study.
abstract: Infant respiratory distress syndrome (IRDS) is a known risk factor for intracerebral haemorrhage/intraventricular haemorrhage (ICH/IVH) and periventricular leucomalacia. These lesions are known to increase the risk of cerebral palsy (CP). Thus, we wanted to examine the long-term risk of CP following IRDS in moderately late and late preterm infants.
  
  
  
  Population-based cohort study.
  
  
  
  All hospitals in Denmark.
  
  
  
  We used nationwide medical registries to identify a cohort of all moderately and late preterm infants (defined as birth during 32-36 full gestational weeks) born in Denmark in 1997-2007 with and without hospital diagnosed IRDS.
  
  
  
  We followed study participants from birth until first diagnosis of CP, emigration, death or end of follow-up in 2014. We computed the cumulative incidence of CP before age 8 years and used Cox's regression analysis to compute HRs of IRDS, comparing children with IRDS to those without IRDS. HRs were adjusted for multiple covariates.
  
  
  
  We identified 39 420 moderately late and late preterm infants, of whom 2255 (5.7%) had IRDS. The cumulative incidence of CP was 1.9% in infants with IRDS and 0.5% in the comparison cohort. The adjusted HR of CP was 2.0 (95% CI 1.4 to 2.9). The adjusted HR of CP was 12 (95% CI 4.5 to 34) in children with IRDS accompanied by a diagnosis of ICH/IVH. After restriction to children without diagnoses of perinatal breathing disorders other than IRDS, congenital heart disease and viral or bacterial infections occurring within 4 days of birth, the overall adjusted HR was 2.1 (95% CI 1.4 to 3.1).
  
  
  
  The risk of CP was increased in moderately late and late preterm infants with IRDS compared with infants without IRDS born during the same gestational weeks.
authors.affiliation: Department of Clinical Epidemiology, Aarhus University Hospital, Aarhus N, Denmark.
authors.forename: Sandra Kruchov
authors.initials: SK
authors.lastname: Thygesen
authors.affiliation: Department of Clinical Epidemiology, Aarhus University Hospital, Aarhus N, Denmark.
authors.forename: Morten
authors.initials: M
authors.lastname: Olsen
authors.affiliation: Department of Paediatrics, Aarhus University Hospital, Aarhus N, Denmark.
authors.forename: John R
authors.initials: JR
authors.lastname: Østergaard
authors.affiliation: Department of Clinical Epidemiology, Aarhus University Hospital, Aarhus N, Denmark Departments of Health Research and Policy (Epidemiology), Stanford University, Stanford, California, USA.
authors.forename: Henrik Toft
authors.initials: HT
authors.lastname: Sørensen
mesh_terms: D001034:Apgar Score; D002543:Cerebral Hemorrhage / Q000150:complications / Q000453:epidemiology*; D002547:Cerebral Palsy / Q000453:epidemiology*; D003718:Denmark / Q000453:epidemiology; D005260:Female; D005500:Follow-Up Studies; D005865:Gestational Age; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D007234:Infant, Premature; D008297:Male; D012127:Respiratory Distress Syndrome, Newborn / Q000150:complications / Q000453:epidemiology*; D012307:Risk Factors
keywords: EPIDEMIOLOGY; PERINATOLOGY; cerebral palsy; cohort study; neurodevelopmental disorder; respiratory distress syndrome