Predictors of renal recovery in Australian and New Zealand end-stage renal failure patients treated with peritoneal dialysis.

OBJECTIVES: The aim of this study was to investigate the factors affecting recovery and durability of dialysis-independent renal function following commencement of peritoneal dialysis (PD).
DESIGN: Retrospective, observational cohort study of the Australian and New Zealand PD patient population.
SETTING: Australia and New Zealand Dialysis and Transplant (ANZDATA) Registry. PARTICIPANTS: The study reviewed all patients in Australia and New Zealand who commenced PD for treatment of end-stage renal failure between 15 May 1963 and 31 December 2004. MAIN OUTCOME MEASURES: The primary outcomes examined were recovery of dialysis-independent renal function and time from PD commencement to recovery of renal function. A secondary outcome measure was time to renal death (patient death or recommencement of renal replacement therapy) following recovery of dialysis-independent renal function.
RESULTS: 24663 patients commenced PD during the study period. Of these, 253 (1%) recovered dialysis-independent renal function. An increased likelihood of recovery was predicted by autoimmune renal disease, hemolytic-uremic syndrome, paraproteinemia, cortical necrosis, renovascular disease, and treatment in New Zealand. A reduced likelihood of recovery was associated with polycystic kidney disease and indigenous race. Analysis of a contemporary subset of 14743 patients in whom complete data were available for body mass index, smoking, and comorbidities yielded comparable results, except that increasing age was additionally associated with a decreased likelihood of recovery. Of the 253 patients who recovered renal function, 151 (60%) recommenced renal replacement therapy and 49 (19%) died within a median period of 226 days (interquartile range 110-581 days). The only significant predictors of continued renal survival after renal recovery were autoimmune renal disease and cortical necrosis.
CONCLUSIONS: Recovery of renal function in patients treated with PD is rare and determined mainly by renal disease type and race. In the majority of cases, recovery is short term. The apparently high rate of early patient death or return to dialysis after recovery of renal function on PD raises questions about the appropriateness of discontinuing PD therapy under such circumstances.