Objective: Our goal was to evaluate whether language delay at 3 years in premature infants is associated with previous exposure to hyperbilirubinemia during the first 2 weeks after birth.
Patients and methods: We performed a retrospective case-control study of infants admitted to the NICU between January and October 2003. Inclusion criteria included a birth weight of < or =1500 g and follow-up to age 3 years. Exclusion criteria included genetic disorders and hearing loss or recurrent ear infections. Peak total serum bilirubin levels during the first 2 weeks and duration of hyperbilirubinemia (days with total serum bilirubin level at >8 mg/dL) were determined. Infants with language delay and who were receiving speech therapy by 3 years were identified through developmental clinic charts and a tracking program and compared with infants who had normal language development.
Results: A total of 125 infants with birth weight of < or =1500 g were admitted to the NICU between January and October 2003. Fifteen infants died, and 110 were discharged from the hospital. A total of 102 (93%) of 110 infants had follow-up to the age of 3 years. Four infants were excluded (1 genetic disorder, 3 delayed hearing loss or recurrent ear infections). Twenty-four infants had a language delay and received speech therapy, whereas 74 infants had normal language development. There was no significant difference in peak total serum bilirubin level and duration of hyperbilirubinemia between the 2 groups. On logistic regression, only bronchopulmonary dysplasia was associated with language delay.
Conclusions: Hyperbilirubinemia, defined as peak total serum bilirubin level or duration of elevated bilirubin in days, is not associated with language delay in premature infants. However, this issue deserves investigation, because other measures of bilirubin, such as unbound bilirubin, may be associated with language delay.