Effect of Egg-white Protein Alone or Combined with Niacin on Nutritional Status, Phosphorus Control, and Circulating FGF-23 in Maintenance Hemodialysis Patients: A Randomized Controlled Trial.

BACKGROUND: Niacin is reported to decrease phosphorus concentration in Maintenance Hemodialysis (MHD) patients. Egg white is one of the main substitutable proteins in MHD patients due to its low phosphorus content. Therefore, we aimed to evaluate the effects of combined egg white and niacin supplementation on dialysis patients' serum phosphorus and nutritional biomarkers.

METHODS: In this randomized controlled clinical trial, 98 patients on MHD were randomly allocated to four groups for eight weeks: 24 g egg white (n=25), 600 g niacin daily (n=24), egg white combined with niacin (n=24), and control (n=24). Calcium, phosphorus, fibroblast growth factor-23, and other nutritional markers were assessed.

RESULTS: There was a significant difference among the groups only in phosphorus at the end of the trial, which was significantly lower in the niacin group (4.38+0.812 mg/dl) than in both the egg white (5.07+0.49 mg/dl) and egg white with niacin supplementation (5.41+0.662 mg/dl) groups. In this regard, albumin increased in egg white and egg white with niacin supplementation, while albumin did not change significantly in the niacin group. Urea reduction ratio and Kt/V rose only in the egg-white group, while aspartate aminotransferase increased only in the niacin and control groups.

CONCLUSION: Niacin decreases serum phosphorus concentration more than egg-white protein or a combined intervention. Egg white protein supplementation has beneficial effects on some nutritional statuses other than phosphorus control without the side effects of niacin.