Association of serum bilirubin with renal outcomes in Han Chinese patients with chronic kidney disease

Abstract

BackgroundOxidative stress and inflammation play pivotal roles in chronic kidney disease (CKD). Bilirubin is an endogenous anti-inflammatory antioxidant. However, the relationship between serum bilirubin and renal outcomes in CKD is controversial. We explored the association of serum bilirubin levels with renal outcomes in Han Chinese patients with CKD. MethodsClinical and laboratory data were collected from 316 patients with CKD. The primary clinical endpoint was renal replacement therapy or death. The association between serum bilirubin and clinical parameters was assessed by correlation analysis. Multiple Cox regression analysis was used to explore the relationship between serum bilirubin and renal outcomes in patients with CKD. ResultsSerum total and indirect bilirubin were positively correlated with estimated glomerular filtration rate, but negatively correlated with 24-h urine protein in patients with CKD. Serum total and indirect bilirubin were inversely associated with CKD stages in patients with CKD stages 1–5. Multiple Cox regression analysis demonstrated that the higher concentration of serum total bilirubin was independently associated with better renal outcomes in CKD. ConclusionsOur results suggest that serum total bilirubin may have protective effects on kidneys.