Higher Peritoneal Transport Status Is Associated with Higher Mortality and Technique Failure in the Australian and New Zealand Peritoneal Dialysis Patient Populations

Abstract

Although early studies observed that peritoneal membrane transport characteristics were determinants of morbidity and mortality in peritoneal dialysis (PD) patients, more recent investigations, such as the Ademex trial, have refuted these findings. The aim of this study was to determine whether baseline peritoneal transport status predicted subsequent survival in Australian and New Zealand PD patients. The study included all adult patients in Australia and New Zealand who commenced PD between April 1, 1999, and March 31, 2004, and had a peritoneal equilibration test (PET) performed within 6 mo of PD commencement. Times to death and death-censored technique failure were examined by Kaplan-Meier analyses and multivariate Cox proportional hazards models. PET measurements were available in 3702 (72%) of the 5170 individuals who began PD treatment in Australia or New Zealand during the study period. In these patients, high transporter status was found to be a significant, independent predictor of death-censored technique failure (adjusted hazard ratio [AHR] 1.23; 95% confidence interval [CI] 1.02 to 1.49; P = 0.03) and mortality (AHR 1.34; 95% CI 1.05 to 1.79, P = 0.02) compared with low-average transport status. High-average transport class was also associated with mortality (AHR 1.21; 95% CI 1.00 to 1.48; P = 0.047) but not death-censored technique failure (AHR 1.04; 95% CI 0.90 to 1.21) compared with low-average transport status. When transport status was alternatively analyzed as a continuous variable, dialysate:plasma creatinine ratio at 4 h was independently predictive of both death-censored technique failure (AHR 1.07; 95% CI 1.01 to 1.295; P = 0.031) and death (AHR 1.09; 95% CI 1.01 to 1.373; P = 0.036 per 0.1 change in dialysate:plasma creatinine). Peritoneal transport rate is a highly significant risk factor for both mortality and death-censored technique failure in the Australian and New Zealand incident PD patient populations.