title: Intelligence at six years in relation to neonatal bilirubin levels: follow-up of the National Institute of Child Health and Human Development Clinical Trial of Phototherapy.
abstract: Results of the National Institute of Child Health and Human Development Randomized Controlled Trial of Phototherapy were examined for the relationship of neonatal bilirubin level to neurological and developmental outcome at 6-year follow-up. This analysis focused on 224 control children with birth weight of less than 2000 g. Bilirubin levels were maintained below previously specified levels by the use of exchange transfusion only (24%). Rates of cerebral palsy were not significantly higher for children with elevated maximum bilirubin level than for those whose level remained low. No association was evident between maximum bilirubin level and IQ (Full Scale, Verbal, or Performance) by simple correlation analysis (r = -.087, P = .2 for Full Scale) or by multiple linear regression adjusting for factors that covary with IQ (beta = -.15, P = .58). IQ was not associated with mean bilirubin level, time and duration of exposure to bilirubin, or measures of bilirubin-albumin binding. Thus, over the range of bilirubin levels permitted in this clinical trial, there was no evidence of bilirubin toxicity to the central nervous system. Measures used to control the level of bilirubin in low birth weight neonates appear to prevent effectively the risk of bilirubin-induced neurotoxicity.
authors.affiliation: Human Learning and Behavior Branch, National Institute of Child Health and Human Development, Bethesda, Maryland 20892.
authors.forename: P C
authors.initials: PC
authors.lastname: Scheidt
authors.forename: B I
authors.initials: BI
authors.lastname: Graubard
authors.forename: K B
authors.initials: KB
authors.lastname: Nelson
authors.forename: D G
authors.initials: DG
authors.lastname: Hirtz
authors.forename: H J
authors.initials: HJ
authors.lastname: Hoffman
authors.forename: L M
authors.initials: LM
authors.lastname: Gartner
authors.forename: D A
authors.initials: DA
authors.lastname: Bryla
mesh_terms: D001663:Bilirubin / Q000097:blood; D001724:Birth Weight; D002547:Cerebral Palsy / Q000209:etiology; D002648:Child; D005500:Follow-Up Studies; D006801:Humans; D007231:Infant, Newborn; D007360:Intelligence; D007567:Jaundice, Neonatal / Q000097:blood / Q000150:complications / Q000628:therapy*; D010789:Phototherapy; D014888:Wechsler Scales
chemical_list: D001663:Bilirubin