Sex-Specific Outcomes in the Peritoneal Dialysis Outcomes and Practice Patterns Study

Sex differences may influence peritoneal dialysis (PD) outcomes for individuals with kidney failure and remain poorly understood. Understanding these differences is important in optimizing dialysis care and addressing disparities in treatment outcomes. We sought to explore association of sex with PD outcomes. Data from the international PD Outcomes and Practice Patterns Study across eight countries were used to examine sex differences in outcomes, including mortality, transfer to hemodialysis, the composite of both, peritonitis risks, and kidney transplantation. Cause-specific Cox regression models were used to assess the association between sex and each clinical outcome, adjusting for region, comorbidities, demographic, and treatment characteristics. Of 26,292 included individuals on PD, 43% were female, ranging from 34% in Japan to 51% in Thailand. Women (compared with men) had lower mortality (rate per 100 patient-years [PY100], 10.9 versus 11.3; adjusted hazard ratio [aHR] of mortality, 0.92 [95% confidence intervals (CIs), 0.86 to 0.99]), transfer to hemodialysis (PY100, 16.3 versus 17.9; aHR, 0.87 [95% CI, 0.83 to 0.92]), the composite of both (PY100, 27.2 versus 29.0; aHR, 0.89 [95% CI, 0.85 to 0.93]), and time to first observed peritonitis (PY100, 17.5 versus 18.7; aHR, 0.90 [95% CI, 0.84 to 0.95]), while transplant hazards were similar (PY100, 4.0 versus 4.0; aHR, 0.97 [95% CI, 0.87 to 1.08]). In subgroup and additional analyses, sex differences in outcomes were particularly apparent in South Korea, with a median time on PD of 6.4 years for women and 4.9 years for men, with South Korea women having lower hemodialysis transfer and transplant rates. Across all countries, diabetes substantially attenuated the lower risks of death and hemodialysis transfer in women. Women had significantly lower risks of gram-positive peritonitis (aHR, 0.73 [95% CI, 0.65 to 0.82]). Compared with men, women receiving PD have lower likelihoods of mortality, hemodialysis transfer, and peritonitis. Better understanding of these findings will help inform sex-specific strategies for managing PD while enhancing personalized care approaches in this patient population.