Determinants of Serum Albumin Concentration Analyzed in a Large Cohort of Patients on Maintenance Hemodialysis

Objective: Serum albumin concentration is a powerful predictor of mortality in patients on chronic hemodialysis (CHD). This study sought to investigate variables associated with serum albumin concentration. Design and Study Population: Cross-sectional study in prevalent chronic hemodialysis patients treated at the Renal Research Institute between July 1, 2005 and October 31, 2005. A total of 4,798 (2,199 females) patients were studied. Main Outcome Measures: Univariate and multivariate relationships of serum albumin concentration with age, sex, race (black, white, other), vascular access type (arteriovenous fistula/graft, catheter), white blood cells, neutrophils, lymphocytes, equilibrated normalized protein catabolic rate (enPCR), dialysis efficacy (eKdrt/V), hemoglobin, phosphate, bio-intact parathyroid hormone [bioPTH], creatinine, alanine aminotransferase (ALT), and aspartate aminotransferase (AST). Results: Age, access type, and variables of 3 domains, namely, nutrition (enPCR; creatinine), eKdrt/V, and inflammation (white blood cells; neutrophil:lymphocyte ratio; hemoglobin), were related to serum albumin. It is interesting to note that AST was the strongest negative predictor of albumin levels. Conclusion: In CHD patients, serum albumin concentration is defined by a complex interaction of inflammation, nutrition, and dialysis efficacy. The relationship between AST and albumin deserves additional study.