Peritoneal Albumin and Protein Losses Do Not Predict Outcome in Peritoneal Dialysis Patients

Background and objectives Peritoneal clearance of albumin unlike the transport of small molecules is defined by both vascular surface area and size-selective permeability. Few studies have supported a positive correlation between peritoneal albumin loss and mortality. The aim of this study was to investigate whether baseline peritoneal loss and clearance of albumin and other proteins is a risk factor of death in peritoneal dialysis patients. Design, setting, participants, & measurements All incident peritoneal dialysis patients in our center during the last 15 years were included. Mass-transfer area coefficient of creatinine and peritoneal clearances of albumin, beta(2)-microglobulin, alpha(2)-macroglobulin, and immunoglobulin G were calculated during a standard peritoneal permeability analysis. The total amount of albumin loss in the dialysate was also calculated. Overall mortality was studied with an intention-to-treat analysis. Results Two hundred fifty-seven patients were included. High baseline albumin clearance was associated with fast transport status, the presence of peripheral arterial disease, and a high comorbidity index, whereas C-reactive protein levels did not differ from the patients with low albumin clearance. Age, high comorbidity score, C-reactive protein levels >10 mg/L, and a low serum albumin were associated with mortality. Peritoneal albumin clearances and albumin loss were not associated with death in crude and adjusted analysis. Similarly, peritoneal clearances of immunoglobulin G, alpha(2)-macroglobulin, and beta(2)-microglobulin were not determinants of survival. Conclusions Baseline peritoneal albumin and protein clearances are associated with signs of comorbidity, but this does not have a measurable effect on patient survival. Clin J Am Soc Nephrol 6: 561-566, 2011. doi: 10.2215/CJN.05540610