Longitudinal Measures of Serum Albumin and Prealbumin Concentrations in Incident Dialysis Patients: The Comprehensive Dialysis Study

Objective: Serum albumin and prealbumin concentrations are strongly associated with the risk of death in dialysis patients. Our study examined the association among demographic characteristics, body composition, comorbidities, dialysis modality and access, inflammation, and longitudinal measures of albumin and prealbumin concentrations in incident dialysis patients. Design, Setting, Subjects, and Outcome Measures: The Comprehensive Dialysis Study is a prospective cohort study of incident dialysis patients; in this report, we examined the data from 266 Nutrition substudy participants who donated serum. The independent variables of interest were baseline age, sex, race, Quetelet's (body mass) index, dialysis modality and access, diabetes, heart failure, atherosclerotic vascular disease, serum creatinine level, and longitudinal measures of C-reactive protein. The outcomes of interest (dependent variables) were longitudinal measures of albumin and prealbumin concentrations, recorded at study entry and thereafter every 3 months for 1 year. Results: In multivariable mixed linear models, female sex, peritoneal dialysis, hemodialysis with a catheter, and higher C-reactive protein concentrations were associated with lower serum albumin concentrations, and serum albumin concentrations increased slightly over the year. In comparison, prealbumin concentrations did not significantly change over time; female sex, lower body mass index, diabetes, atherosclerotic vascular disease, and higher C-reactive protein concentrations were associated with lower prealbumin concentrations. Serum creatinine had a curvilinear relation with serum albumin and prealbumin. Conclusions: Serum albumin level increases early in the course of dialysis, whereas prealbumin level does not, and the predictors of serum concentrations differ at any given time. Further understanding of the mechanisms underlying differences between albumin and prealbumin kinetics in dialysis patients may lead to an improved approach to the management of protein-energy wasting. (c) 2013 by the National Kidney Foundation, Inc. All rights reserved.