Serum bilirubin is inversely associated with insulin resistance and metabolic syndrome among children and adolescents

Objective: Bilirubin is a potent antioxidant and a cyroprotectant. Low serum bilirubin is associated with atherosclerosis. Little is known about its role in metabolic syndrome (MS) among children and adolescents. Methods: We examined 4723 children and adolescents aged 12-17 years with reliable measures of various serum hepatic profiles and metabolic risks from Health and Nutrition Examination Survey 1999-2004. Results: The results showed that the prevalence of the MS was from 6.6 ± 1.2% in the lowest quartile to 2.1 ± 1.9% in the highest quartile of the concentration of total bilirubin. The graded association remained significant after the adjustment of other co-variates. The odds ratios for the MS were around 0.29 (0.08-0.99) and 0.23 (0.08-0.65) for the upper two quartiles when using the lowest quartile as reference for the concentration of total bilirubin. The quartiles of the serum total bilirubin levels were inversely correlated with the homeostasis model assessment (HOMA-IR) and insulin while not associated with the serum C-reactive protein (CRP) levels. Conclusions: The serum total bilirubin levels are inversely correlated with the prevalence of the MS. The mechanism of the association between MS and total bilirubin may be related to the insulin resistance status.