# The effect of dialysis modality on annual mortality: A prospective cohort study

## TL;DR

This study compares hemodialysis and peritoneal dialysis in ESRD patients and finds that hemodialysis may be better for younger patients with diabetes over long-term follow-ups.

## Contribution

The study introduces a novel analysis of dialysis modality effects using weighted Fine and Gray models and landmark analysis in a large prospective cohort.

## Key findings

- No significant overall difference in mortality hazard between hemodialysis and peritoneal dialysis.
- Peritoneal dialysis showed higher mortality risk in patients under 65 and those with diabetes after 4-5 years.
- Landmark analysis revealed higher hazard rates for peritoneal dialysis at specific follow-up points in certain subgroups.

## Abstract

Despite numerous studies on the effect of each dialysis modality on mortality, the issue remains controversial. We investigated the hazard rate of mortality in patients with incident end-stage renal disease (ESRD) concerning initial dialysis modality (hemodialysis vs. peritoneal dialysis). Using a nationwide, multicenter, prospective cohort in South Korea, we studied 2207 patients, of which 1647 (74.6%) underwent hemodialysis. We employed the weighted Fine and Gray model over the follow-up period using inverse probability of treatment and censoring weighting. Landmark analysis was used for identifying the changing effect of dialysis modality on individuals who remained event-free at each landmark point. No significant difference in hazard rate was observed overall. However, the peritoneal dialysis group had a significantly higher hazard rate than the hemodialysis group among patients under 65 years after 4- and 5- year follow-up. A similar pattern was observed among those with diabetes mellitus. Landmark analysis also showed the higher hazard rate for peritoneal dialysis at 2 years for the education-others group and at 3 years for the married group. These findings may inform dialysis modality decisions, suggesting a preference for hemodialysis in young patients with diabetes, especially for follow-ups longer than 3 years.