Does Whey Protein Supplementation Improve the Nutritional Status in Hypoalbuminemic Peritoneal Dialysis Patients?

Limited data are available regarding the effects of whey protein on the nutritional status of the peritoneal dialysis population. This study evaluated the effects of whey protein supplementation for 12 weeks on the nutritional status in hypoalbuminemic peritoneal dialysis patients. Thirty-six stable adult patients on maintenance peritoneal dialysis with serum albumin levels <3.5 g/dL were enrolled in the study and were divided into two groups similar in their serum albumin and normalized protein equivalent of total nitrogen appearance (nPNA). Nineteen patients were instructed to receive 1.2 g/kg per day of protein diet and additional whey protein supplement at a dose of 25% of the instructed daily protein diet (whey protein group), and 17 patients were instructed to receive 1.2 g/kg per day protein diet without additional whey protein supplementation (control group). Nutritional status was assessed using two measures: nPNA and lean tissue mass index (LTI) obtained by whole-body bioimpedance spectroscopy technique. In the whey protein group serum albumin and nPNA significantly increased from baseline to week 6 (P < 0.001, P = 0.034; respectively) and from week 6 to week 12 (P < 0.001, P = 0.001; respectively); LTI significantly increased from week 6 to week 12 (P = 0.022). Compared to the control group at week 12, serum albumin, nPNA and LTI values were significantly higher in the whey protein group (P < 0.001, P = 0.002, P = 0.001; respectively). This study demonstrated for the first time that oral supplementation with whey protein improves nutritional status and is well tolerated in hypoalbuminemic PD patients.