how to normalize the protein equivalent of total nitrogen appearance (PNA)?
Background. The protein equivalent of total nitrogen appearance (PNA) is assumed to be a reliable estimate of dietary protein intake in haemodialysis patients. Protein requirements are related to body size. In order to standardize PNA to individual differences in body size, PNA is normalized to various terms related to the patient’s body weight. It is not clear which is the most appropriate method to normalize PNA. Methods. We calculated five commonly used variants of normalized PNA and related them to indices of nutritional status in 57 stable chronic haemodialysis patients, 57±15 (mean±SD) years of age. PNA, determined by direct dialysate quantification, was normalized to actual post-dialysis dry body weight (DBW), normal body weight (DBWnormal), lean body mass (LBM), normal lean body mass (LBMnormal), and `normalized’ body weight (N). Nutritional status was assessed using an index of nutrition composed of anthropometry derived parameters and plasma albumin concentration. Results. PN
