Abstract: 【Abstract】Objective To explore the relationship between serum total bilirubin (TBIL) level and allcause mortality and cardiovascular disease (CVD)-related mortality in continuous ambulatory peritoneal dialysis (CAPD) patients. Methods We reviewed patients undergoing CAPD at the First Affiliated Hospital of Zhengzhou University from September 1, 2012 to May 31, 2019. They were followed up until August 31, 2019. Baseline demographics and laboratory test results were collected. Patients were divided into three groups according to baseline serum TBIL: low bilirubin group (≤4.0 μmol/L), moderate bilirubin group (4.0～5.4 μmol/L), and high bilirubin group (>5.4 μmol/L). Kaplan-Meier survival curve was used to compare the survival rates of the three groups. Cox regression model was used to evaluate the risk factors for all-cause mortality and CVD-related mortality. Results A total 217 CAPD patients were enrolled in this study, with the median age of 45 (35.5, 52) years old and 136 (62.7%) males. The overall median survival time was 70(37,＞81)months. The median survival periods of low bilirubin group (n=72), moderate bilirubin group (n=75) and high bilirubin group (n=70) were >75（56，＞75）months, 63（28，＞81）months and 58（30，70）months, respectively. There were statistical differences in diastolic blood pressure, albumin, blood magnesium, white blood cells, dot total protein, left ventricular diameter, total urea clearance index (Kt/V), and proportion of diabetes among the three groups (R <0.05, respectively). Kaplan-Meier survival curves showed higher survival rate in low bilirubin group (R <0.05). After adequate adjustment, multivariate Cox regression analysis showed that low serum TBIL level was an independent protective factor for all-cause mortality (HR=0.365, 95% CI: 0.140～0.952,R =0.039) and CVD-related mortality (HR=0.208, 95% CI: 0.051～0.858, R =0.030) in CAPD patients. Conclusion Serum TBIL is associated with mortality risk of all-cause mortality and CVD-related mortality in CAPD patients and can be a valuable indicator for the prognosis of CAPD patients.

Key words: Peritoneal dialysis, Bilirubin, Mortality, Cardiovascular disease