Survival advantage of peritoneal dialysis relative to hemodialysis in the early period of incident dialysis patients: A nationwide prospective propensity-matched study in Korea

Background: The impact of dialysis modality on survival is still somewhat controversial. Given possible differences in patients' characteristics and the cause and rate of death in different countries, the issue needs to be evaluated in Korean cohorts. Methods: A nationwide prospective observational cohort study (NCT00931970) was performed to compare survival between peritoneal dialysis (PD) and hemodialysis (HD). A total of 1,060 end-stage renal disease patients in Korea who began dialysis between September 1, 2008 and June 30, 2011 were followed through December 31, 2011. Results: The patients (PD, 30.6%; HD, 69.4%) were followed up for 16.3±7.9 months. PD patients were significantly younger, less likely to be diabetic, with lower body mass index, and larger urinary volume than HD patients. Infection was the most common cause of death. Multivariate Cox regression with the entire cohort revealed that PD tended to be associated with a lower risk of death compared to HD [hazard ratio (HR) 0.63, 95% confidence interval (CI) 0.36-1.08]. In propensity score matched pairs (n = 278 in each modality), cumulative survival probabilities for PD and HD patients were 96.9% and 94.1% at 12 months (P = 0.152) and 94.3% and 87.6% at 24 months (P = 0.022), respectively. Patients on PD had a 51% lower risk of death compared to those on HD (HR 0.49, 95% CI 0.25-0.97). Conclusions: PD exhibits superior survival to HD in the early period of dialysis, even after adjusting for differences in the patients' characteristics between the two modalities. Notably, the most common cause of death was infection in this Korean cohort.