title: Respiratory distress syndrome at birth is a risk factor for hospitalization for lower respiratory tract infections in infancy.
abstract: BACKGROUND
  Respiratory distress syndrome (RDS) and hospitalization for lower respiratory tract infection (LRTI; specifically, respiratory syncytial virus) are important causes of morbidity in infancy. Whether RDS at birth is an independent risk factor for LRTI is unknown. This study estimated the risk of LRTI-related hospitalization among late preterm infants with a history of RDS.
  
  
  METHODS
  The population-based cohort from Québec included all late preterm infants (32-36 weeks gestational age) born in 1996 to 1997. RDS was identified by International Classification of Diseases, Ninth Revision code 769, and a comparison cohort generated from all without RDS. A multivariable model estimated the adjusted odds ratio of LRTI-related hospitalization among late preterm infants with a history of RDS; and the incidence and increased risk of childhood chronic respiratory morbidity was calculated.
  
  
  RESULTS
  Of the 7488 late preterms, 459 (6.1%) had a history of RDS; 525 late preterms (7.0%) were hospitalized for LRTI in infancy, including 57 (12.4%) with RDS. The adjusted odds ratio for LRTI-related hospitalization associated with RDS was 1.6 (1.2-2.2). Other significant risk factors included male sex, or diagnosis of other respiratory conditions, diaphragm anomalies, bacteremia, intraventricular hemorrhage, congenital heart disease or respiratory system anomalies. Late preterm infants with a history of RDS were also at a significantly increased risk of childhood chronic respiratory morbidity.
  
  
  CONCLUSIONS
  Late preterms with a history of RDS are at a 60% increased risk of LRTI-related hospitalization in infancy compared with late preterm infants without RDS. Such infants may benefit from interventions decreasing the risk of contracting respiratory viruses causing acute LRTI.
authors.affiliation: Oxford Outcomes, Vancouver, British Columbia, Canada.
authors.forename: Shelagh M
authors.initials: SM
authors.lastname: Szabo
authors.forename: Katherine L
authors.initials: KL
authors.lastname: Gooch
authors.forename: Ellen E
authors.initials: EE
authors.lastname: Korol
authors.forename: Pamela
authors.initials: P
authors.lastname: Bradt
authors.forename: Pamela
authors.initials: P
authors.lastname: Vo
authors.forename: Adrian R
authors.initials: AR
authors.lastname: Levy
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D005260:Female; D006760:Hospitalization; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D011792:Quebec / Q000453:epidemiology; D012127:Respiratory Distress Syndrome, Newborn / Q000150:complications*; D012141:Respiratory Tract Infections / Q000453:epidemiology*; D012189:Retrospective Studies; D012307:Risk Factors