Serum ceruloplasmin level as a predictor for the peritoneal dialysis technique survival

INTRODUCTION AND AIMS: There are a limited number of studies devoted to the association between an antioxidant status and peritoneal dialysis (PD) adequacy and technical survival. The present study was undertaken to investigate some blood antioxidant biomarkers and their potential effects on PD technical survival.

METHODS: This single-center, cross-sectional cohort study was conducted for between January 2010 and May 2015. 44 (31 males, 13 females) stable ambulatory non-diabetic patients with ESRD on PD were included in the study. All the patients had been undergoing continuous ambulatory PD (CAPD) for more than 3 months. They were observed during a period of 36 months to determine the impact of antioxidant status on the dialysis technical survival. The mean age in the patient population was 48.9 ± 13.2 yrs. The diabetics and the patients with a history of peritonitis or significant illness / hospitalization in the previous 3 months were excluded. The average duration of PD therapy at this study entry (at baseline) was 29 [18.5-37] months. The control group consisted of 30 healthy individuals. Survival curves were constructed according to the Kaplan-Meier method and compared using the log-rank test. A technical failure was defined as all causes of discontinuation of PD. The durations of technique survival were calculated from the date of inclusion in the study. For this analysis, in January 2010, the patients were categorized into two groups according to the baseline CP level.

RESULTS: During the 3-yrs follow-up, 9 of 44 (20.5 %) patients dropped out from PD; 7 patients were considered to be ‘technique failures’, but, they continued PD treatment for various reasons: the inability to formation of an adequate vascular access 3 (6.8 %), the patient's refusal to transfer to hemodialysis 2 (4.5 %) and non-compliance 2 (4.5 %). The baseline CP level in the PD patients was significantly decreased compared to the control group (0.09 [0.07 - 0.1] g/L vs 0.22 [0.19 - 0.23] g/L; P < 0.0001). But, the average serum CP level in the 28 patients of the ‘technique survival’ group was significantly higher compared with the 16 patients of the ‘technique failure’ group (0.26 [0.22 - 0.32] g/L vs 0.09 [0.07 - 0.1] g/L, p < 0.0001). There were no significant differences in the demographic and baseline PD characteristics of the patients in the two groups stratified according to CP levels, excluding PD technique survival (P = 0.001). The results of the Kaplan-Meier analysis and log-rank test also demonstrated that there was a significant difference in the cumulative technical survival rate between the patients with CP level < 0.19 g/L and CP level ≥ 0.2 g/L (log-rank test: χ2 = 11.3, P = 0.0008, Figure 1). The hazard ratio for the technique failures was significantly higher in the lowest CP tertile category compared with the highest CP level (HR, 4.8; 95% confidence interval, 1.2 to 18.7; P=0.002).

CONCLUSIONS: We have found out a decrease in the serum ceruloplasmin level in the PD patients. Baseline serum ceruloplasmin level is an independent predictive factor for the PD technical survival. Further studies are needed to identify the opportunities for antioxidant therapy to improve the PD technique survival.