title: TSAT is a better predictor than ferritin of hemoglobin response to Epoetin alfa in US dialysis patients.
abstract: Clinical guidelines recommend concurrent treatment of anemia in end-stage renal disease with erythropoiesis-stimulating agents (ESAs) and iron. However, there are mixed data about optimal iron supplementation. To help address this gap, the relationship between iron markers and hemoglobin (Hb) response to ESA (Epoetin alfa) dose was examined. Electronic medical records of 1902 US chronic hemodialysis patients were analyzed over a 12-month period between June 2009 and June 2010. The analysis included patients who had at least one Hb value during each 4-week interval for four consecutive intervals (k - 2, k - 1, k, and k + 1; k is the index interval), received at least one ESA dose during intervals k - 1 or k, had at least one transferrin saturation (TSAT) value at interval k, and at least one ferritin value during intervals k - 2, k - 1, or k. Effect modification by TSAT and ferritin on Hb response was evaluated using the generalized estimating equations approach. Patients had a mean (standard deviation) age of 62 (15) years; 41% were Caucasian, 34% African American, 65% had hypertension, and 39% diabetes. Transferrin saturation, but not ferritin, had a statistically significant (P < 0.05) modifying effect on Hb response. Maximum Hb response was achieved when TSAT was 34%, with minimal incremental effect beyond these levels. Of the two standard clinical iron markers, TSAT should be used as the primary marker of the modifying effect of iron on Hb response to ESA. Long-term safety of iron use to improve Hb response to ESA warrants further study.
authors: Division of Nephrology, Department of Medicine, University of Louisville, Louisville, Kentucky, USA.
authors: Adam E
authors: AE
authors: Gaweda
authors: Premila
authors: P
authors: Bhat
authors: Gregory A
authors: GA
authors: Maglinte
authors: Chun-Lan
authors: CL
authors: Chang
authors: Jerrold
authors: J
authors: Hill
authors: Grace S
authors: GS
authors: Park
authors: Akhtar
authors: A
authors: Ashfaq
authors: Matthew
authors: M
authors: Gitlin
mesh_terms: D003920:Diabetes Mellitus / Q000097:blood / Q000628:therapy; D057286:Electronic Health Records; D000068817:Epoetin Alfa; D004921:Erythropoietin / Q000008:administration & dosage*; D005260:Female; D005293:Ferritins; D006397:Hematinics / Q000008:administration & dosage*; D006454:Hemoglobins / Q000378:metabolism*; D006801:Humans; D006973:Hypertension / Q000097:blood / Q000628:therapy; D007676:Kidney Failure, Chronic / Q000097:blood / Q000628:therapy; D008297:Male; D008954:Models, Biological; D017410:Practice Guidelines as Topic; D011237:Predictive Value of Tests; D011994:Recombinant Proteins / Q000008:administration & dosage; D006435:Renal Dialysis; D014481:United States
chemical_list: D006397:Hematinics; D006454:Hemoglobins; D011994:Recombinant Proteins; D004921:Erythropoietin; D000068817:Epoetin Alfa; D005293:Ferritins
keywords: Anemia; end-stage renal disease; erythropoiesis-stimulating agent; hemoglobin; iron
references: Am J Health Syst Pharm. 2012 Feb 15;69(4):310-20
references: 22302256
references: J Am Soc Nephrol. 2007 Mar;18(3):975-84
references: 17267740
references: Am J Nephrol. 2009;29(6):571-81
references: 19136818
references: J Am Soc Nephrol. 1998 May;9(5):869-76
references: 9596085
references: Clin J Am Soc Nephrol. 2010 Apr;5(4):576-81
references: 20110344
references: Am J Kidney Dis. 2011 Jun;57(6):822-31
references: 21530036
references: Am J Kidney Dis. 2009 May;53(5):823-34
references: 19339087
references: Circulation. 2002 Oct 22;106(17):2212-7
references: 12390950
references: Hippokratia. 2011 Jan;15(Suppl 1):39-43
references: 21897757
references: J Am Soc Nephrol. 2000 Mar;11(3):530-538
references: 10703677
references: Am J Kidney Dis. 2001 Mar;37(3):564-72
references: 11228181
references: Kidney Int. 2008 Nov;74(10):1237-40
references: 18596731
references: J Am Soc Nephrol. 2005 Oct;16(10):3070-80
references: 16033854
references: Biometrics. 1988 Dec;44(4):1049-60
references: 3233245
references: Am J Med. 2012 Oct;125(10):991-999.e1
references: 22998881
references: Am J Kidney Dis. 2004 Apr;43(4):671-84
references: 15042544
references: Am J Kidney Dis. 2003 Oct;42(4):761-73
references: 14520627