title: Measurement of Hba(1C) in patients with chronic renal failure.
abstract: BACKGROUND
  Carbamylated hemoglobin (carbHb) is reported to interfere with measurement and interpretation of HbA(1c) in diabetic patients with chronic renal failure (CRF). There is also concern that HbA1c may give low results in these patients due to shortened erythrocyte survival.
  
  
  METHODS
  We evaluated the effect of carbHb on HbA(1c) measurements and compared HbA(1c) with glycated albumin (GA) in patients with and without renal disease to test if CRF causes clinically significant bias in HbA(1c) results by using 11 assay methods. Subjects included those with and without renal failure and diabetes. Each subject's estimated glomerular filtration rate (eGFR) was used to determine the presence and degree of the renal disease. A multiple regression model was used to determine if the relationship between HbA(1c) results obtained from each test method and the comparative method was significantly (p<0.05) affected by eGFR. These methods were further evaluated for clinical significance by using the difference between the eGRF quartiles of >7% at 6 or 9% HbA(1c). The relationship between HbA(1c) and glycated albumin (GA) in patients with and without renal failure was also compared.
  
  
  RESULTS
  Some methods showed small but statistically significant effects of eGFR; none of these differences were clinically significant. If GA is assumed to better reflect glycemic control, then HbA(1c) was approximately 1.5% HbA(1c) lower in patients with renal failure.
  
  
  CONCLUSIONS
  Although most methods can measure HbA(1c) accurately in patients with renal failure, healthcare providers must interpret these test results cautiously in these patients due to the propensity for shortened erythrocyte survival in renal failure.
authors: Department of Pathology and Anatomical Sciences, University of Missouri School of Medicine, One Hospital Dr., Columbia, MO 65212, USA. littler@health.missouri.edu
authors: Randie R
authors: RR
authors: Little
authors: Curt L
authors: CL
authors: Rohlfing
authors: Alethea L
authors: AL
authors: Tennill
authors: Steven E
authors: SE
authors: Hanson
authors: Shawn
authors: S
authors: Connolly
authors: Trefor
authors: T
authors: Higgins
authors: Charles E
authors: CE
authors: Wiedmeyer
authors: Cas W
authors: CW
authors: Weykamp
authors: Richard
authors: R
authors: Krause
authors: William
authors: W
authors: Roberts
mesh_terms: D002851:Chromatography, High Pressure Liquid; D006442:Glycated Hemoglobin / Q000032:analysis*; D017127:Glycation End Products, Advanced; D006801:Humans; D007676:Kidney Failure, Chronic / Q000175:diagnosis*; D012044:Regression Analysis; D012709:Serum Albumin / Q000032:analysis; D000093423:Glycated Serum Albumin
chemical_list: D006442:Glycated Hemoglobin; D017127:Glycation End Products, Advanced; D012709:Serum Albumin; D000093423:Glycated Serum Albumin; C517652:hemoglobin A1c protein, human