Reduced residual renal function is a risk of peritonitis in continuous ambulatory peritoneal dialysis patients

Background. Loss of residual renal function (RRF) contributes to anaemia, inflammation and malnutrition and is also a strong predictor of mortality in continuous ambulatory peritoneal dialysis (CAPD) patients. However, the role of RRF on peritonitis is not yet clearly established. This study aimed to evaluate the effect of RRF on the development of peritonitis. Methods. Study subjects were 204 end-stage renal disease (ESRD) patients who started PD from January 2000 to December 2005. Biochemical and clinical data within 1 month of PD commencement were considered as baseline. To determine risk factors for peritonitis, multivariate Cox regression was performed. Kaplan-Meier analysis and log-rank test were used to examine the difference of peritonitis-free period according to the presence of diabetes and RRF. Results. On univariate analysis basedon baseline data in first peritonitis, diabetes was less prevalent and RRF (6.7 ± 2.6 vs 4.0 ± 2.3 ml/min/1.73 m², P < 0.01), haemoglobin (10.9 ± 1.2 vs 10.6 ± 1.2 g/dl, P < 0.05) and serum albumin level (3.6 ± 0.4 vs 3.4 ± 0.4 g/dl, P < 0.01) were significantly higher in the peritonitis-free group. Kaplan-Meier analysis showed that time to first PD peritonitis episode was significantly longer in the non-diabetic patients (P < 0.001) and in patients with higher residual GFR (P < 0.001). Multivariate analysis showed that diabetes [hazard ratio(HR) 1.64, P < 0.05] and RRF (per 1 ml/min/1.73 m² increase, HR 0.81, P < 0.01) were independent risk factors. Conclusion. Our study revealed that RRF and diabetes were risk factors for peritonitis. These results suggest that preservation of RRF should be viewed as a protective strategy to reduce peritonitis.