Serum transferrin and serum prealbumin are early predictors of serum albumin in chronic hemodialysis patients

Abstract

Protein-calorie malnutrition is a known risk factor for increased morbidity and mortality in maintenance hemodialysis patients (MHD). Serum albumin is the most commonly measured nutritional index in MHD patients because of its easy routine availability and association with outcomes of interest. However, its long half-life of approximately 20 days makes it a late index of nutritional status, and its exclusive use may delay implementation of appropriate nutritional interventions. Serum prealbumin and transferrin have been proposed as earlier nutritional markers. However, the temporal associations among these indices and serum albumin have not been well documented. To assess the ability of serum prealbumin and serum transferrin to predict changes in serum albumin over time, we prospectively analyzed these parameters in 105 MHD patients every month for 6 consecutive months. The mixed model analysis showed that early changes in either serum transferrin or prealbumin predicted and were significantly associated with changes in serum albumin ( P < .0001). Using a prototype equation, a change of 0.12 g/dL in serum albumin concentration can be predicted by a 10% change in the same direction of serum transferrin and prealbumin. We conclude that clinically significant changes in albumin can be reliably predicted by earlier changes in serum transferrin and prealbumin.