Neonatal hyperbilirubinemia at high altitude
C. Leibson, M. Brown, S. Thibodeau, D. Stevenson, H. Vreman, R. Cohen, G. Clemons, W. Callen and L. G. Moore
Department of Anthropology, University of Colorado, Denver.
A previous retrospective study showed an increased frequency of neonatal
hyperbilirubinemia at high altitude in Colorado. In a prospective study we
found that 39% of newborns at 3100 m altitude vs 16% at 1600 m exhibited
hyperbilirubinemia, defined as a day 3 serum bilirubin level of 205 mumol/L
or higher. Increased bilirubin production at 3100 m vs 1600 m was shown by
increased levels of corrected carboxyhemoglobin. This finding was supported
by increased erythropoietin and bilirubin values in cord blood and
increased hematocrit values at day 3 among infants at 3100 m vs 1600 m. The
sustained elevation in bilirubin for breast-fed vs formula-fed infants at
1600 m was observed for both feeding types at 3100 m. The findings
suggested that there is a hematologic response to decreased oxygen
availability at high altitude, resulting in increased bilirubin production
accompanied by delayed bilirubin clearance.
