Serum albumin is strongly associated with erythropoietin sensitivity in hemodialysis patients.
OBJECTIVE
In hemodialysis patients, the hematological response to erythropoietin (epo) is variable and clinical factors that explain this variability are incompletely understood. We tested the hypothesis that the variability in hemoglobin (Hgb) response (epo sensitivity) is determined by key nutritional, inflammation, and oxidative stress markers.


METHODS
Eighty-two consecutive patients on hemodialysis had 3 consecutive monthly predialysis evaluations of Hgb, total white blood cell (WBC) count, serum albumin, malondialdehyde (MDA), and monocyte chemoattractant protein-1 (MCP1). We analyzed the time course of Hgb in relationship to serum albumin, WBC, MDA, MCP1, epo and iron administration, and tests of iron sufficiency in a linear growth curve model.


RESULTS
Subjects with higher Hgb had a fall in Hgb and vice versa, regressing to a mean Hgb (SD) of 11.8 g/dl (1.8 g/dl). Whereas the average slope of Hgb was flat, the SD of slopes was 0.63 g/dl, which explained 39% of the variance in Hgb. Nonuse of epo was associated with a mean Hgb change of -0.18 g/dl (95% confidence interval [CI] -0.26 to -0.10) per 10,000 IU epo/mo (P < 0.05). Epo use was associated with steeper rate of change at 0.04 g/dl per mo per 10,000 IU (95% CI 0.01 to 0.07) (P < 0.01). Hgb at baseline was 0.73 g/dl higher for each 1-g/dl increase in albumin, and the rate of change increased by 0.49 g/dl per mo for each 1-g/dl increase in albumin concentration. WBC, MDA, or MCP1 had no role in predicting the baseline Hgb or its change over time.


CONCLUSIONS
Serum albumin concentration is an important predictor of both baseline Hgb and epo sensitivity in chronic hemodialysis patients. Factors that improve serum albumin may also improve Hgb in hemodialysis patients.
Division of Nephrology, Department of Medicine, Indiana University School of Medicine, and the Richard L. RoudebushVA Medical Center, Indianapolis, Indiana 46202, USA. ragarwal@iupui.edu
Rajiv
R
Agarwal
Joyce L
JL
Davis
Linda
L
Smith
D000328:Adult; D000368:Aged; D000740:Anemia / Q000097:blood / Q000188:drug therapy*; D015415:Biomarkers; D018932:Chemokine CCL2 / Q000097:blood; D004921:Erythropoietin / Q000627:therapeutic use*; D005260:Female; D006454:Hemoglobins / Q000378:metabolism; D006801:Humans; D007249:Inflammation / Q000097:blood; D007676:Kidney Failure, Chronic / Q000097:blood / Q000150:complications*; D007958:Leukocyte Count; D008297:Male; D008315:Malondialdehyde / Q000097:blood; D008875:Middle Aged; D018384:Oxidative Stress; D011237:Predictive Value of Tests; D011446:Prospective Studies; D006435:Renal Dialysis; D012709:Serum Albumin / Q000378:metabolism*; D016896:Treatment Outcome
D015415:Biomarkers; C111835:CCL2 protein, human; D018932:Chemokine CCL2; D006454:Hemoglobins; D012709:Serum Albumin; D004921:Erythropoietin; D008315:Malondialdehyde