(126) Risk of Peritonitis in Continuous Ambulatory Peritoneal Dialysis and Automated Peritoneal Dialysis

Background: Peritoneal dialysis (PD) is a crucial kidney replacement therapy, but peritonitis poses a significant complication. This study explores the risk of first peritonitis in continuous ambulatory peritoneal dialysis (CAPD) and automated peritoneal dialysis (APD).

Objectives: To compare the risk of peritonitis of APD to CAPD.

Methods: Design
A retrospective cohort study

Setting
Adult patients on PD in Hong Kong from 2007 to 2019

Exposure
APD, Disc System, Stay Safe Balance®, and UltraBag®

Main outcome
The primary outcome was peritonitis. Secondary outcomes included all-cause mortality, cardiovascular death, accident and emergency department attendance, and technique failure (switch from peritoneal dialysis to hemodialysis)

Statistical Analysis
Propensity score weighting was used to balance patient characteristics. Weighted Cox proportional-hazards models assessed risks, with Kaplan–Meier estimates illustrating cumulative incidence. Subgroup analyses were conducted for different entry age, sex and diabetes status.

Results: Among 11,021 patients included, 68.7% used UltraBag®, while 9.7%, 12.0%, and 9.6% used automated peritoneal dialysis, Disc System, and Stay Safe Balance®, respectively. APD users were younger and had less comorbidities. APD demonstrated a significantly lower risk of peritonitis compared to other modalities [Disc System: HR 1.88 (95% CI, 1.51 to 2.33); Stay Safe Balance: HR 2.22 (95% CI, 1.76 to 2.80); UltraBag: HR 1.93 (95% CI, 1.61 to 2.33) versus APD]. No significant differences were observed in all-cause mortality and technique failure. Subgroup analyses supported the main findings, except for an increased risk of all-cause mortality and cardiovascular death observed in male patients using UltraBag® system, while a reduction in risk of cardiovascular death in female patients was observed in different CAPD modalities versus APD.

Conclusions: This study, the first to categorize PD modalities individually, reveals that APD is associated with a lower risk of first peritonitis. While no significant mortality differences were found, further research is needed to explore this relationship.