Hyperbilirubinemia in Inuit neonates.

A prospective study was undertaken to determine if Inuit and Caucasian neonates have different patterns of physiologic jaundice. Daily blood samples obtained by heel pricks of Inuit and Caucasian neonates born at the Churchill (Man.) Health Centre were assayed for the total serum bilirubin concentration. The mean peak bilirubin level in the Inuit group was significantly higher than that in the Caucasian group (8.76 v. 6.04 mg/dl [150 v. 103 mumol/l]) and occurred later (on day 3 rather than day 2). Of the Caucasian neonates, those who were breast-fed in hospital had a significantly higher (P less than 0.05) mean peak bilirubin level than those who were not, and among all the neonates who were not breast-fed in hospital the Inuit had a significantly higher mean peak bilirubin level than the Caucasians (7.98 v. 3.64 mg/dl [136 v. 62 mumol/l]). These findings indicate that factors other than breastfeeding, some of which may be genetic, are responsible for the higher and later peak in the serum bilirubin concentration in Inuit neonates.