title: Association between the severity of chronic lung disease and first-year outcomes of very low birth weight infants.
abstract: OBJECTIVE
  The objective of this study was to determine if there is an association between the severity of chronic lung disease in very low birth weight infants (as assessed by the duration of supplemental oxygen requirements in the neonatal period) and first-year neurodevelopmental, sensory, and growth outcomes as well as duration of neonatal hospitalization and first-year hospital readmissions.
  
  
  METHODS
  Retrospective chart review with matched subject groups.
  
  
  METHODS
  The subjects of this study were very low birth weight infants born between 1987 and 1991 in a 17-county perinatal region of North Carolina. Infants were categorized into one of three groups on the basis of duration of supplemental oxygen requirements. Infants who were breathing room air by 28 days were classified as having no chronic lung disease; infants who required supplemental oxygen at 28 days but not at 36 weeks postmenstrual age were classified as having mild chronic lung disease; and infants who required supplemental oxygen at 36 weeks postmenstrual age were classified as having severe chronic lung disease. Infants were matched for birth weight, sex, and race. The matched groups (n = 174) were compared with respect to the incidence of first year adverse neurodevelopmental and sensory outcomes, growth patterns, and hospital readmissions during the first year. Results were analyzed with general linear models and logistic regression analyses.
  
  
  RESULTS
  The incidence of any adverse neurodevelopmental or sensory outcome increased as severity of chronic lung disease increased from none (3.6%) to mild (21.4%) to severe (31.6%, p < 0.001). Growth patterns were similar in infants with no and mild chronic lung disease, but infants with severe chronic lung disease were significantly lighter (p < 0.01) and shorter (p < 0.005) at 40 weeks postmenstrual age and significantly lighter at 1 year adjusted age (p < 0.05). The duration of the initial hospitalization increased with chronic lung disease severity (p < 0.001). Infants with severe chronic lung disease were readmitted to the hospital significantly more often (p < 0.005) than infants with no chronic lung disease or mild chronic lung disease.
  
  
  CONCLUSIONS
  Very low birth weight infants who required supplemental oxygen at or beyond 28 days were at increased risk for adverse neurodevelopmental and sensory outcomes, but only those infants who continued to require supplemental oxygen at 36 weeks were at increased risk for poor growth and readmission to the hospital.
authors.affiliation: Department of Pediatrics, Children's Healthcare-St. Paul, MN, USA.
authors.forename: R A
authors.initials: RA
authors.lastname: deRegnier
authors.forename: D
authors.initials: D
authors.lastname: Roberts
authors.forename: D
authors.initials: D
authors.lastname: Ramsey
authors.forename: R G
authors.initials: RG
authors.lastname: Weaver
authors.forename: T M
authors.initials: TM
authors.lastname: O'Shea
mesh_terms: D016022:Case-Control Studies; D002908:Chronic Disease; D002658:Developmental Disabilities / Q000453:epidemiology*; D005260:Female; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D019102:Infant, Very Low Birth Weight; D007902:Length of Stay; D008171:Lung Diseases / Q000453:epidemiology* / Q000628:therapy; D008297:Male; D010102:Oxygen Inhalation Therapy; D010359:Patient Readmission; D012189:Retrospective Studies; D012307:Risk Factors; D012720:Severity of Illness Index; D013997:Time Factors