Predictors of outcomes in patients on peritoneal dialysis: A 2-year nationwide cohort study

There has been no nationwide study of prognostic factors and outcomes in patients on peritoneal dialysis (PD) in Japan. We conducted a cohort study using data from the nationwide registry of the Japanese Society for Dialysis Therapy. We followed 8,954 prevalent PD patients for 2 years, 2014–2015. Cox proportional hazards regression analysis was used to determine factors that were independently associated with patient survival. Survival rates were compared between patients with and without diabetes after adjusting for potential confounders. During the 2-year study period, 893 (10.0%) of 8,954 patients died, 148 (1.6%) underwent kidney transplantation, and 2,637 (29.4%) were switched to hemodialysis; 5,276 (58.9%) patients were alive at the end of the study period. After multivariate adjustment, older age, longer duration of dialysis, presence of diabetes, cardiovascular comorbidity, use of 2.5% glucose dialysate, higher C-reactive protein and phosphate levels, and a lower serum albumin level were independently associated with increased hazard ratios for all-cause mortality. A combination of PD and hemodialysis was associated with a lower mortality rate. The new-onset cardiovascular event rate was significantly higher in the diabetes group than in the non-diabetes group (P < 0.0001). After adjusting for all variables, the hazard ratio was 1.509 (95% confidence interval 1.029–2.189, P = 0.036) in the diabetes group. Diabetes, older age, longer duration of dialysis, cardiovascular comorbidity, and inflammation were predictors of mortality in patients on PD.