Clinical and genetic risk factors for moderate hyperbilirubinemia in Brazilian newborn infants

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)⩾12.9 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 tb⩾12.9 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.