title: Hemoglobin variability in chronic kidney disease: a cross-sectional study.
abstract: BACKGROUND
  The ability to maintain dialysis patients' hemoglobin (Hgb) within narrow targets remains a significant clinical problem. This study was designed to determine the variability in Hgb values for patients with chronic kidney disease (CKD) receiving or not receiving erythropoiesis-stimulating agents (ESAs) compared with patients on dialysis receiving ESAs.
  
  
  METHODS
  This cross-sectional review of anemia management in CKD and dialysis patients analyzed Hgb variability by patient-year, defined as the coefficient of variability calculated for individual patients. One hundred thirty-seven CKD patient-years and 350 dialysis patient-years were available for analysis. Hgb variability was defined as the coefficient of variability calculated as the individual patient's Hgb standard deviation divided by the patient's mean Hgb times 100.
  
  
  RESULTS
  The coefficient of variability in Hgb values were significantly less in patients with CKD not treated with ESAs than in patients with CKD treated with ESAs whether they were receiving dialysis (medians: 3.96 versus 8.53%, P < 0.05) or not receiving dialysis (medians: 3.96 versus 7.37%, P < 0.05).
  
  
  CONCLUSIONS
  CKD and hemodialysis patients receiving treatment with ESAs have significantly greater Hgb variability than patients with CKD not receiving ESAs. This finding suggests that the current practice pattern for the administration of exogenous ESAs is partly responsible for the observed Hgb variability.
authors.affiliation: Department of Medicine, University of Colorado Denver Health Sciences Center, Denver, Colorado 80262, USA. david.spiegel@uchsc.edu
authors.forename: David M
authors.initials: DM
authors.lastname: Spiegel
mesh_terms: D000465:Algorithms; D000740:Anemia / Q000628:therapy; D003430:Cross-Sectional Studies; D004921:Erythropoietin / Q000378:metabolism; D005919:Glomerular Filtration Rate; D006397:Hematinics / Q000627:therapeutic use; D006454:Hemoglobins / Q000032:analysis*; D006801:Humans; D007676:Kidney Failure, Chronic / Q000097:blood* / Q000175:diagnosis*; D012016:Reference Values; D012044:Regression Analysis; D006435:Renal Dialysis / Q000379:methods; D012621:Seasons; D013997:Time Factors
chemical_list: D006397:Hematinics; D006454:Hemoglobins; D004921:Erythropoietin