Acute neurological findings in a national cohort of neonates with severe neonatal hyperbilirubinemia

Abstract

To describe and compare infants with severe hyperbilirubinemia, who presented with and without abnormal neurological findings and to identify associated risk factors. Data on infants with severe hyperbilirubinemia (>425 μmol l⁻¹ and/or received exchange transfusion) were collected prospectively through the Canadian Paediatric Surveillance Program (CPSP) from 2002 to 2004. Cases were categorized into two groups on the basis of information provided by the reporting physician: neurologically normal or abnormal. Demographic characteristics were compared and univariate logistic regression was performed to identify factors associated with acute neurological abnormalities in infants. Of the initial cohort of 258 infants, 32 (12.4%) were identified to have neurological abnormalities. Infants in the highest peak bilirubin level group (>550 μmol l⁻¹) had the greatest risk of acute neurological abnormalities. The mid range (451 to 550 μmol l⁻¹) and lowest level (450 μmol l⁻¹) groups were less likely to have abnormalities (odds ratio (OR)=0.174; P=0.0013 and 0.402; P=0.0613, respectively). Exchange transfusion and presentation within the first 2 days of age were positively associated with abnormal neurological findings in infants (OR=3.332, P=0.003 and OR=2.572, P<0.0001, respectively). In this national cohort of infants with severe hyperbilirubinemia, a significant percentage of infants developed acute bilirubin encephalopathy. Long-term neurodevelopmental follow-up is necessary to determine the incidence of permanent neurological sequelae.