Risk factors of peritoneal dialysis-related peritonitis in the Japan Peritoneal Dialysis Outcomes and Practice Patterns Study(PDOPPS)

Background. Peritoneal dialysis(PD) -related peritonitis is a major complication of PD. Wide variations in peritonitis prevention, treatment strategies and consequences are seen between countries. These between-country differences may result from modifiable risk factors and clinical practices. Methods. A total of 1225 Japanese PD patients were included and prospectively followed in the Peritoneal Dialysis Outcomes and Practice Patterns Study phase 1(2014-2018) and phase 2(2018-2022) . Associations between PD-related peritonitis and various risk factors were assessed by Cox proportional hazards survival models. Results. During follow-up(median 1.52 years), 539 peritonitis episodes were experienced by 364 patients. The country crude peritonitis rate was 0.27 episodes/patient-year. In the fully adjusted model, noticeable patient-level factors associated with experiencing any peritonitis included age {hazard ratio [HR] 1.07 per 5-year increase [95% confidence interval(CI) 1.01-1.14]}, serum albumin level [HR 0.63 per 1 g/dl higher(95% CI 0.48-0.82) ] and continuous ambulatory peritoneal dialysis(PD) [HR 1.31 versus automated PD(95% CI 1.05-1.63) ]. The adoption of antibiotic prophylaxis practice at the time of PD catheter insertion [HR 0.63(95% CI 0.51-0.78) ] or when having complicated dental procedures [HR 0.74 (95% CI 0.57-0.95) ] or lower endoscopy [HR 0.69(95% CI 0.54-0.89) ] were associated with lower hazards of any peritonitis, while a routine facility practice of having more frequent regular medical visits was associated with a higher hazard. Conclusion. Identification of risk factors in Japan may be useful for developing future versions of guidelines and improving clinical practices in Japan. Investigation of country-level risk factors for PD-related peritonitis is useful for developing and implementing local peritonitis prevention and treatment strategies.