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

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.

Change in access blood flow over time predicts vascular access thrombosis.

BACKGROUND: Vascular access thrombosis accounts for at least $1 billion dollars in annual expenses and 25% of hospitalizations for chronic hemodialysis patients. Low vascular access blood flow (less than 800 ml/min) has been shown to modestly increase the relative risk for thrombosis in the subsequent three months. In this study, it is hypothesized that a time-dependent decrease in vascular access blood flow may be more predictive of subsequent thrombosis especially in vascular accesses with flows more than 800 ml/min, since it would indicate the development of a critical outlet stenosis in the graft. METHODS: Ninety-five accesses in 91 CHD patients were prospectively followed over 18 months. Vascular access blood flow was measured every six months by the ultrasound dilution technique. Thrombotic events were recorded during the three study periods. RESULTS: A total of 34 thrombotic events in 95 accesses were documented through the total study duration. Accesses that thrombosed had a 22% decrease in vascular access blood flow during the first observation period and a further 41% decrease during the second observation period as compared to 4% drop and 15% increase during the first and second observation periods, respectively, for accesses that did not thrombose. There was an estimated 13.6-fold (95%, confidence interval 2.68 to 69.16) increase in the relative risk of thrombosis for accesses with more than 35% decrease in vascular access blood flow compared to those accesses with no change in blood flow. There was no statistical difference in the average vascular access blood flow of all patients over the study period. CONCLUSIONS: Accesses that show a large (>15%) decrement in vascular access blood flow are associated with a high risk of thrombosis. Serial measurements of vascular access blood flow predict access thrombosis.