Objective: To identify clinical and genetic risk factors for moderate hyperbilirubinemia during the first week of life.Study Design: Using univariate and multivariate multiple regression analyses, the RR for clinical factors, the African variant of glucose-6-phosphate dehydrogenase (G6PD) deficiency (G202A/A376G), and (TA) n UGT1A1 polymorphisms were established in a cohort of 608 Brazilian newborn infants. Hyperbilirubinemia was monitored until 134.5±49.8 h of life (IQR, 111.0 to 156.7). The dependent variable was total bilirubinemia (TB)X12.9 mg per 100 ml estimated by transcutaneous or plasma bilirubin measurements.Result: The African variant of G6PD deficiency and (TA) 7 /(TA) 7 and (TA) 7 /(TA) 8 polymorphisms present in 6.1 and 12.0% of newborns, respectively, were not risk factors for moderate hyperbilirubinemia. Coexpression of G6DP deficiency and UGT1A1 polymorphisms occurred in 0.49% of the subjects. Independent clinical predictors for TBX12.9 mg per 100 ml were gestational age <38 weeks and reference curve percentiles >P40th.
Conclusion:In this study, G6PD deficiency and UGT1A1 gene promoter polymorphisms were not risk factors for moderate hyperbilirubinemia. Genetic factors may vary considerably in importance among different populations.