Recovery of renal function and the discontinuation of dialysis in patients treated with continuous peritoneal dialysis.

OBJECTIVE: Previous studies have shown that patients with end-stage renal disease (ESRD) treated with continuous peritoneal dialysis (CPD) have better preservation of endogenous renal function than patients treated with hemodialysis (HD). We wondered if this better preservation of endogenous renal function seen with CPD patients translates into the improved likelihood of recovery of endogenous renal function in those patients with potentially reversible causes of renal failure.
METHODS: To evaluate this question, we reviewed the records of all 1200 patients that completed CPD training at a large, freestanding peritoneal dialysis center in New Haven, Connecticut, between 1979 and 1999, and the records of all patients completing CPD training in New England between 1993 and 1998. In New Haven, about half the new patients with ESRD were started on CPD compared to only 15% in New England. We then compared the chances of recovery of renal function in these two cohorts of CPD patients to the chances of recovery of renal function in two groups of HD patients. The first group consisted of all patients that started on HD in New England between 1993 and 1998. The second group consisted of all patients that started HD in our HD unit in New Haven, Connecticut, between 1993 and 1999. The data on the New England patients were provided by the ESRD Network of New England. All patients entered into the present study had to have been on dialysis for a minimum of 3 months, as in the United States Renal Data System database, and had to have recovered sufficient renal function to be able to be maintained off dialysis for a minimum of 30 days.
RESULTS: 29 of 1,200 CPD patients (2.4%) trained in New Haven recovered sufficient renal function to permit the discontinuation of dialysis for a minimum of 30 days. In comparison, only 305 of 19,032 patients (1.6%) managed with HD in New England (p < 0.05 compared to New Haven CPD patients) and 3 of 430 patients (0.7%) in our HD center (p < 0.05 compared to New Haven CPD patients) recovered sufficient glomerular filtration rate (GFR) to allow the discontinuation of dialysis for at least 30 days. If only those CPD patients that initiated dialysis between 1993 and 1999 in New Haven were analyzed, 15 of 369 (4.1%) recovered sufficient GFR to allow discontinuation of dialysis for at least 30 days (p < 0.025 compared to both groups of HD patients). Of the 2,924 patients completing CPD training in New England, 60 (2.1%) recovered renal function; this percentage is not significantly different from the percent of HD patients in New England recovering renal function.
CONCLUSION: Although the present study is a retrospective study and the actual criteria for selection of CPD and HD therapy are not controlled for, the data raise the question of whether there may be a therapeutic advantage to treating newly diagnosed ESRD patients, that have a potentially reversible cause of renal failure, with CPD.