Peritoneal dialysis clearance can replace residual renal function

. Objective: There is controversy whether increasing peritoneal clearance e ffectively substitutes for declining residual renal function. We studied th e impact of renal and peritoneal clearances on outcome, controlling for com orbidity, . Design: Registry database. . Settings: Four dialysis centers. . Patients: Incident peritoneal dialysis patients. . Methods: Data were collected prospectively on 90 incident patients betwee n 1991 and 1999. At the end of their first year on peritoneal dialysis, pat ients were divided into groups based on the first year's clearance results: group 1 (n = 62) had weekly Kt/V greater than or equal to 2.0 and creatini ne clearance (CCr/1.73 m(2)) greater than or equal to 60 L throughout the f irst year; group 2 (n = 28) fell below these targets due to loss of residua l renal function and then reached targets due to prescription change. . Main Outcome Measures: Patient and technique survival. . Results: Both groups were similar in baseline characteristics except age (57 years vs 49 years, p = 0.02) and initial albumin (34.4 g/L vs 37.5 g/L, p = 0.001). One-year patient survival after grouping was similar in both g roups (86.3% vs 80.9%, p = 0.72). Cox proportional hazard model, controllin g for comorbidity, did not show "group" to be a significant predictor of ou tcome (p = 0.96). One-year technique survival after grouping was similar in both groups (77.3% vs 83.2%, log rank p = 0.89). For technique failure, Co x proportional hazard model showed peritonitis (p = 0.004) to be the only s ignificant predictor of worse outcome. . Conclusions: Peritoneal dialysis patients with improved clearances due to prescription changes had survival comparable to patients who never fell be low target. This suggests that loss of residual renal function may be repla ced by increasing peritoneal dialysis clearance. A large multicenter trial to study this important question further is needed.