Study On The Relationship Between Total Bilirubin In Serum And All Cause Death In Peritoneal Dialysis Patients

Objective:To investigate the predictive value and influencing factors of serum total bilirubin level and all-cause and cardiovascular mortality in peritoneal dialysis patients.Methods:Selected from January 1,2013 to December 31,2015,in the second affiliated hospital of kunming medical university kidney internal medicine diagnosed with end-stage kidney disease,and for the first time in our hospital for peritoneal dialysis(PD)treatment for 3 months and older patients,3 years follow-up observation,the deadline is December 31,2018,all dialysis patients were followed up to:turn to other medical center,hemodialysis,a kidney transplant,death,lost to follow-up and tracking observation to the termination date of this research.According to the median value of serum total bilirubin of dialysis patients(median value of serum total bilirubin was 5.9mmol/L),the enrolled patients were divided into two groups:(1)LB group:namely,low serum total bilirubin(LSTBIL),serum total bilirubin?5.9mmol/L;(2)HB group:namely,high serum total bilirubin group(HSTBIL),serum total bilirubin?5.9mmol/L.Collect the clinical data and laboratory data of the patients,Including:demographic data(such as:gender,age,height,weight,age of dialysis,primary disease);Complications(such as diabetes,hypertension,coronary artery disease,cardiovascular disease,cerebrovascular disease,lung disease,digestive system disease,tumor)and laboratory indicators(such as serum total bilirubin,serum albumin,blood creatinine,blood urea nitrogen,total cholesterol,triglyceride,blood uric acid,calcium,phosphorus,blood leukocyte,hemoglobin).EPI formula was used to estimate glomerular filtration rate.Statistical methods SPSS 21.0 statistical software was used for data analysis,and Spearman correlation analysis was conducted between each research factor and serum total bilirubin.Kaplan-meier method was used to compare the survival rates of the two groups with all-cause death and cardiovascular event death as clinical outcomes,and Cox regression model was used to analyze the correlation between serum total bilirubin and all-cause death and cardiovascular event death in peritoneal dialysis patients.P?0.05 was considered statistically significant.Results:(1)A total of 126 adult peritoneal dialysis patients were included in this study.The average age of the patients was 52.84± 13.50 years old,and 83 were males(65.9%).The age of dialysis was 25.00(13.00,39.00)months,and 42 patients died during follow-up period,27 patients died of cardiovascular events,6 cases died of cerebrovascular accident,5 cases died of infection,1 case died of gastrointestinal bleeding,3 cases died of malignant tumors.(2)the LB group of total bilirubin,direct bilirubin,indirect bilirubin,glomerular filtration rate is lower than HB group,differences were statistically significant(all P?0.05).blood urea nitrogen,blood creatinine,phosphorus,calcium and phosphorus products in the LB group were all higher than those in the serum HB group,and the differences were statistically significant(all P?0.05).(3)Spearman correlation analysis showed that serum total bilirubin was positively correlated with dialysis age,glomerular filtration rate,calcium,hematocrit and hemoglobin(all P?0.05).The serum total bilirubin was negatively correlated with calcium and phosphorus product,urea nitrogen,creatinine,uric acid and phosphorus,and the differences were statistically significant(all P?0.05).(4)kaplan-meier survival curve showed that,with all-cause death as the clinical outcome,LB in PD patients with HB group 1 year,2 years,3 years of survival rate of 88.7%compared to 93.2%,82.6%,compared to 87.75%,15.8%,more than 59.9%.With death from cardiovascular events as the clinical outcome,the 1-year,2-year and 3-year survival rates of PD patients in the LB group and the HB group were 91.7%compared with 98.2%,87.2%compared with 92.5%,and 32.9%compared with 77.9%,respectively.The survival rate of PD patients in LB group was lower than that in HB group,and the difference between groups was statistically significant(P<0.05).The median value of direct bilirubin(2.1 mmol/L)was divided into two groups:the lower DBIL group(LD group)and the higher DBIL group(HD group).With all-cause death as the clinical outcome,The 1-year,2-year and 3-year survival rates of PD patients in LD group and HD group were 89.1%compared with 93.0%,81.0%compared with 90.2%,and 20.1%compared with 56%,respectively.With death from cardiovascular events as the clinical outcome,the 1-year,2-year and 3-year survival rates of PD patients in LD group and HD group were 93.4%compared with 96.5%,86.7%compared with 93.6%,and 38.9%compared with 72.6%,respectively.The median indirect bilirubin of 3.75mmol/L was divided into two groups:the lower IBIL group(LI group)and the higher IBIL group(HI group).The 1-year,2-year and 3-year survival rates of PD patients in LI group and HI group were 84.9%compared with 96.8%,80.4%compared with 89.6%,and 17.9%compared with 54.7%,respectively,with all-cause death as the clinical outcome.The 1-year,2-year and 3-year survival rates of PD patients in the LI group and the HI group were 91.1%compared with 98.3%,88.4%compared with 91.0%,and 33.7%compared with 72.0%,respectively.In the median group of total bilirubin,direct bilirubin and indirect bilirubin,the survival rate of patients in the LB,LD and LI groups was lower,and the differences between the groups were statistically significant(P?0.05).(5)Fully corrected multivariate Cox regression analysis showed LSTBIL was an independent risk factor for all-cause death(HR=2.855.95%CI:1.476?5.524,P=0.002)and death from cardiovascular events(HR=3.501,95%CI:1.442?8.498,P=0.006)in peritoneal dialysis patients,with statistically significant differences(P?0.05).Serum direct bilirubin was an independent risk factor for all-cause death(HR=2.776,95%CI:1.229?6.272,P=.014)and death from cardiovascular events(HR=4.408,95%CI:1.491?13.034,P=0.007)in PD patients,and the differences were statistically significant(P?0.05).Low serum indirect bilirubin was an independent risk factor for all-cause death in PD patients(HR=3.232,95%CI:1.347?7.755,P=0.009),and the correlation with death from cardiovascular events was not statistically significant(HR=3.566,95%CI:0.982?12.950,P=0.053).Conclusion(s):1.Serum total bilirubin in peritoneal dialysis patients is negatively correlated with blood urea nitrogen and blood creatinine,and positively correlated with glomerular filtration rate.patients with serum total bilirubin level is higher,the glomerular filtration rate is relatively high,it is suggested that the residual renal function is better in patients with higher serum total bilirubin level.2.In PD patients,the 3-year cumulative survival rate of the low-serum total bilirubin group,the low-serum direct bilirubin group and the low-serum indirect bilirubin group was lower than that of the high-serum total bilirubin group,the high-serum direct bilirubin group and the high-serum indirect bilirubin group,respectively.It is suggested that serum bilirubin is related to the prognosis of patients.Patients with low serum bilirubin have poor prognosis.3.Low serum total bilirubin and low serum direct bilirubin are independent risk factors for all-cause death and cardiovascular death in PD patients.With the decrease of serum total bilirubin and direct bilirubin,the risk of all-cause death and cardiovascular events death in PD patients increases.Serum total bilirubin and direct bilirubin may be one of the valuable indicators to predict the mortality risk of PD patients.