Relationship between serum bilirubin levels and mortality in patients on peritoneal dialysis

Associations between liver function parameters and poor clinical outcomes in peritoneal dialysis patients

Patients with end-stage renal disease (ESRD) have significantly lower survival rates compared with the general population of the same age. Peritoneal dialysis (PD) is an effective treatment for patients with ESRD, but the clinical outcome of PD patients is still not promising. The survival of PD patients is associated with various clinical factors, and exploring some valid risk predictors may be beneficial for this population. In this review, by integrating the latest research, we summarized the association of some common and novel liver function parameters (ALT, AST, ALP, GGT, serum bilirubin, pre-albumin, albumin, albumin-globulin ratio [AGR], serum ferritin, and hyaluronic acid) with clinical outcomes in PD patients. It may contribute to a better understanding of potential risk factors and help to develop strategies to prevent the disease progression.

Preexisting Cardiovascular Disease, Hypertension, and Mortality in Peritoneal Dialysis

Background

Preexisting cardiovascular disease (CVD) and hypertension are each associated with poor prognosis in peritoneal dialysis (PD) patients. Joint associations of preexisting CVD and hypertension have not been comprehensively evaluated in this population.

Methods

We conducted a retrospective cohort study of 3073 Chinese incident PD patients from five dialysis centres between January 1, 2005, and December 31, 2018. The joint associations between preexisting CVD, hypertension, and mortality were analysed using Cox regression models.

Results

Over a median of 33.7 months of follow-up, 581 (18.6%) patients died, with 286 (9.3%) deaths due to CVD. After adjusting for confounding factors, the preexisting CVD coexisting with hypertension, preexisting CVD, and hypertension groups had higher risks of all-cause mortality (hazard ratio [HR]: 3.97, 95% confidence interval [CI]: 3.06 to 5.15; HR: 2.21, 95% CI: 1.29 to 3.79; and HR: 1.83, 95% CI: 1.47 to 2.29, respectively) and CVD mortality (HR: 4.68, 95% CI: 3.27 to 6.69; HR: 2.10, 95% CI: 0.95 to 4.62; and HR: 1.86, 95% CI: 1.36 to 2.54, respectively) than the control group without preexisting CVD or hypertension (p for trend < 0.001). There was no interaction between subgroup analyses (p > 0.05). The joint associations showed similar patterns using the Fine-Gray competing risk models.

Conclusions

Preexisting CVD and hypertension at the start of PD were additive prognostic utilities for mortality, and preexisting CVD was more strongly associated with mortality than hypertension.

Relationship Between Serum Indirect Bilirubin Levels and Cardiovascular Events and All-Cause Mortality in Maintenance Hemodialysis Patients

Purpose

Unconjugated bilirubin is one of the most endogenous antioxidant substances. Mildly elevated total bilirubin concentrations may protect against cardiovascular disease and total death. However, most studies only focused on the association between serum total bilirubin and the risk of cardiovascular disease and total death. This study aimed to investigate the relationship between serum indirect bilirubin (IBIL) and the cardiovascular events in maintenance hemodialysis patients.

Patients and Methods 

This retrospective cohort study included 284 maintenance hemodialysis patients. Patients were divided into two groups according to the median IBIL level: high IBIL group (IBIL ≥3.0 μmol/L) and low IBIL group (IBIL <3.0 μmol/L). All demographic and laboratory data were recorded at baseline. The endpoint was cardiovascular events and all-cause mortality.

Results

During the median follow-up time of 62 months, 96 patients developed cardiovascular disease. There were 134 deaths. In Kaplan-Meier analysis curves, the risk of cardiovascular events in the low IBIL group was significantly higher than high IBIL group (P < 0.001). In multivariate Cox regression analysis, the risk of cardiovascular events in high IBIL group was 0.484 times (95% CI 0.278-0.844, P = 0.010) the risk in low IBIL group. However, there was no significant association between serum IBIL level and all-cause mortality (P = 0.269).

Conclusion

Our findings suggest that lower circulating IBIL levels were associated with the increased risk of cardiovascular events in maintenance hemodialysis patients.

Peritoneal dialysis outcomes in patients with nephrotic syndrome: a propensity score-matched cohort study

INTRODUCTION

It is unclear whether patients with end-stage renal disease (ESRD) and nephrotic syndrome (NS) can be treated with peritoneal dialysis (PD).

OBJECTIVES

To investigate the outcomes of PD treatment in ESRD patients with or without NS.

METHODS

In this retrospective cohort study, all incident patients with ESRD and NS who started PD from 1 February 2006 to 31 December 2017, were matched with patients without NS using propensity scores based on age, sex, diabetes mellitus status, and serum albumin.

RESULTS

Fifty-three patients in the NS PD group and 53 matched controls were included. The median survival of the NS PD group was comparable to that of the non-NS PD group. An interaction effect was observed between survival time and baseline NS status. Thus, patients' outcomes within and after 1.5 years were analyzed separately. Both mortality (log-rank test, p= .235) and technique failure (log-rank test, p= .543) rates within 1.5 years in patients with NS were comparable to those of the non-NS group. After 1.5 years, however, the NS status at baseline was associated with lower all-cause mortality (p= .020) and lower technique failure (p= .008) rates in PD patients compared with the non-NS group. The multivariable Cox regression analysis showed that compared with the patients in the non-NS PD group, PD patients with NS had both significantly lower all-cause mortality and lower technique failure rate after adjusting for other factors.

CONCLUSIONS

Our study indicates that PD may be considered as a long-term renal replacement therapy for patients with ESRD and baseline NS.