Comparison of Long-Term Outcomes between Peritoneal Dialysis Patients with Diabetes as a Primary Renal Disease or as a Comorbid Condition

OBJECTIVE: To investigate the long-term outcomes of peritoneal dialysis (PD) patients with diabetes as primary renal disease and patients with diabetes as a comorbid condition. METHODS: All diabetic patients who commenced PD between January 1, 1995 and June 30, 2012 at Ren Ji Hospital, China were included. Patients were divided into diabetic nephropathy group (DN group) and non-diabetic nephropathy group (NDN group) according to their diagnosis of primary renal disease at the initiation of PD. They were followed until death, cessation of PD, transferred to other centers or to the end of study (June 30, 2013). Outcomes were analyzed by Kaplan-Meier method and Cox regression models. RESULTS: A total of 163 diabetic patients were enrolled in the study, including 121 (74.2%) in DN group and 42 (25.8%) in NDN group. The 1-, 2-, 3- and 5-year patient survival rates were 89%, 78%, 66% and 51% for DN group, and 85%, 63%, 53% and 25% for NDN group, respectively. Kaplan-Meier analysis showed that patients in NDN group had a worse patient survival compared with DN group (log rank 4.830, P=0.028). Patients in NDN group had a marginally shorter peritonitis-free period (log rank 3.297, P=0.069), however, there was no significant difference in technique survival (log rank 0.040, P=0.841). Multivariate Cox regression analysis showed that older age (HR 1.047, 95% CI 1.022-1.073, p<0.001), cardiovascular disease comorbidity (HR 2.200, 95% CI 0.1.269-3.814, P=0.005) and diabetes as a comorbidity condition (HR 1.806, 95% CI 1.003-3.158, P=0.038) were the independent predictors of increased mortality. CONCLUSIONS: PD patients with diabetes as a comorbidity had an inferior patient survival compared to those with diabetic nephropathy, and closer monitoring and extra attention in the former subgroup of patients are therefore warranted.