The Effect of Dialysis Modality on Annual Mortality: a Prospective Cohort Study

Abstract Despite several studies on the effect of each dialysis modality on mortality, the subject is still controversial. We investigated the hazard rate of mortality for patients with incident end-stage renal disease with respect to initial dialysis modality (hemodialysis vs. peritoneal dialysis). We used a nationwide, multicenter, prospective cohort of patients with end-stage renal disease who were undergoing dialysis in South Korea. Among the 2 207 patients, 1 647 (74.6%) underwent hemodialysis. We performed the intention-to-treatment analysis, and employed inverse probability treatment weighting to reduce bias and the weighted Fine and Gray model over the follow-up period. Landmark analysis was used to identify the changing effect of the dialysis modality on individuals who remained event-free at each landmark point. No significant difference in hazard rate was observed between the two dialysis modalities when all participants were considered. However, the hazard rate in the peritoneal dialysis group was significantly higher than that in the hemodialysis group among patients aged <65 years after 4- and 5-year follow-up. A similar pattern was observed among patients with diabetes mellitus. Landmark analysis showed that the hazard ratio in the peritoneal dialysis group was significantly higher than that in the hemodialysis group at 2 years in both the education-others and married groups. This study could be useful for choosing a dialysis modality for young patients, especially in the presence of diabetes. Moreover, hemodialysis may be preferred to peritoneal dialysis when the follow-up duration is >3 years.