Hemoglobin A_1c: Teaching a New Dog Old Tricks
Authors: William H. Herman, Robert M. Cohen
Journal: Annals of Internal Medicine (2010)

Editorials15 June 2010Hemoglobin A1c: Teaching a New Dog Old TricksWilliam H. Herman, MD, MPH and Robert M. Cohen, MDWilliam H. Herman, MD, MPHFrom University of Michigan, Ann Arbor, Michigan 48109; and University of Cincinnati, Cincinnati, OH 45267.Search for more papers by this author and Robert M. Cohen, MDFrom University of Michigan, Ann Arbor, Michigan 48109; and University of Cincinnati, Cincinnati, OH 45267.Search for more papers by this authorAuthor, Article, and Disclosure Informationhttps://doi.org/10.7326/0003-4819-152-12-201006150-00011 SectionsAboutFull TextPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinkedInRedditEmail In 1976, Koenig and colleagues (1, 2) suggested that hemoglobin A1c (HbA1c) might be a useful indicator of both glucose tolerance and glucose regulation in diabetes. Currently, HbA1c level is an accepted measure of glycemic control in patients with diabetes, an indicator of the risk for diabetic complications, and a measure of the quality of diabetes care. In 2010, the American Diabetes Association recommended that HbA1c level, when measured by using clinical laboratory equipment and not point-of-care instruments, is also useful for diagnosing diabetes (3). Among the advantages of using HbA1c for diagnosis are that the test does not require ...References1. Koenig RJ, Peterson CM, Kilo C, Cerami A, Williamson JR. Hemoglobin A1c as an indicator of the degree of glucose intolerance in diabetes. Diabetes. 1976;25:230-2. [PMID: 1254113] CrossrefMedlineGoogle Scholar2. Koenig RJ, Peterson CM, Jones RL, Saudek C, Lehrman M, Cerami A. Correlation of glucose regulation and hemoglobin AIc in diabetes mellitus. N Engl J Med. 1976;295:417-20. [PMID: 934240] CrossrefMedlineGoogle Scholar3. International Expert Committee. International Expert Committee report on the role of the A1c assay in the diagnosis of diabetes. Diabetes Care. 2009;32:1327-34. [PMID: 19502545] CrossrefMedlineGoogle Scholar4. Selvin E, Crainiceanu CM, Brancati FL, Coresh J. Short-term variability in measures of glycemia and implications for the classification of diabetes. Arch Intern Med. 2007;167:1545-51. [PMID: 17646610] CrossrefMedlineGoogle Scholar5. Consensus Committee. Consensus statement on the worldwide standardization of the hemoglobin A1c measurement: the American Diabetes Association, European Association for the Study of Diabetes, International Federation of Clinical Chemistry and Laboratory Medicine, and the International Diabetes Federation. Diabetes Care. 2007;30:2399-400. [PMID: 17726190] MedlineGoogle Scholar6. Goldstein DE, Little RR, Lorenz RA, Malone JI, Nathan D, Peterson CM. Tests of glycemia in diabetes. Diabetes Care. 1995;18:896-909. [PMID: 7555528] CrossrefMedlineGoogle Scholar7. National Glycohemoglobin Standardization Program. Factors that interfere with GHB (HbA1c) test results. 2009. Accessed at www.ngsp.org/prog/factors.htm on 26 April 2010. Google Scholar8. Cook JD, Finch CA, Smith NJ. Evaluation of the iron status of a population. Blood. 1976;48:449-55. [PMID: 953365] CrossrefMedlineGoogle Scholar9. Coban E, Ozdogan M, Timuragaoglu A. Effect of iron deficiency anemia on the levels of hemoglobin A1c in nondiabetic patients. Acta Haematol. 2004;112:126-8. [PMID: 15345893] CrossrefMedlineGoogle Scholar10. Saaddine JB, Fagot-Campagna A, Rolka D, Narayan KM, Geiss L, Eberhardt M, et al. Distribution of HbA1c levels for children and young adults in the U.S.: Third National Health and Nutrition Examination Survey. Diabetes Care. 2002;25:1326-30. [PMID: 12145229] CrossrefMedlineGoogle Scholar11. Eberhardt MS, Lackland DT, Wheeler FC, German RR, Teutsch SM. Is race related to glycemic control? An assessment of glycosylated hemoglobin in two South Carolina communities. J Clin Epidemiol. 1994;47:1181-9. [PMID: 7722552] CrossrefMedlineGoogle Scholar12. Herman WH, Ma Y, Uwaifo G, Haffner S, Kahn SE, Horton ES; Diabetes Prevention Program Research Group. Differences in A1c by race and ethnicity among patients with impaired glucose tolerance in the Diabetes Prevention Program. Diabetes Care. 2007;30:2453-7. [PMID: 17536077] CrossrefMedlineGoogle Scholar13. Viberti G, Lachin J, Holman R, Zinman B, Haffner S, Kravitz B, et al; ADOPT Study Group. A Diabetes Outcome Progression Trial (ADOPT): baseline characteristics of type 2 diabetic patients in North America and Europe. Diabet Med. 2006;23:1289-94. [PMID: 17116177] CrossrefMedlineGoogle Scholar14. Herman WH, Dungan KM, Wolffenbuttel BH, Buse JB, Fahrbach JL, Jiang H, et al. Racial and ethnic differences in mean plasma glucose, hemoglobin A1c, and 1,5-anhydroglucitol in over 2000 patients with type 2 diabetes. J Clin Endocrinol Metab. 2009;94:1689-94. [PMID: 19276235] CrossrefMedlineGoogle Scholar15. Nathan DM, Kuenen J, Borg R, Zheng H, Schoenfeld D, Heine RJ; A1c-Derived Average Glucose Study Group. Translating the A1c assay into estimated average glucose values. Diabetes Care. 2008;31:1473-8. [PMID: 18540046] CrossrefMedlineGoogle Scholar16. Ziemer DC, Kolm P, Weintraub WS, Vaccarino V, Rhee MK, Twombly JG, et al. Glucose-independent, black–white differences in hemoglobin A1c levels. A cross-sectional analysis of 2 studies. Ann Intern Med. 2010;152:770-7. LinkGoogle Scholar17. Yudkin JS, Forrest RD, Jackson CA, Ryle AJ, Davie S, Gould BJ. Unexplained variability of glycated haemoglobin in non-diabetic subjects not related to glycaemia. Diabetologia. 1990;33:208-15. [PMID: 2347434] CrossrefMedlineGoogle Scholar18. Gould BJ, Davie SJ, Yudkin JS. Investigation of the mechanism underlying the variability of glycated haemoglobin in non-diabetic subjects not related to glycaemia. Clin Chim Acta. 1997;260:49-64. [PMID: 9101100] CrossrefMedlineGoogle Scholar19. Cohen RM, Holmes YR, Chenier TC, Joiner CH. Discordance between HbA1c and fructosamine: evidence for a glycosylation gap and its relation to diabetic nephropathy. Diabetes Care. 2003;26:163-7. [PMID: 12502674] CrossrefMedlineGoogle Scholar20. Hudson PR, Child DF, Jones H, Williams CP. Differences in rates of glycation (glycation index) may significantly affect individual HbA1c results in type 1 diabetes. Ann Clin Biochem. 1999;36:451-9. [PMID: 10456207] CrossrefMedlineGoogle Scholar21. McCarter RJ, Hempe JM, Gomez R, Chalew SA. Biological variation in HbA1c predicts risk of retinopathy and nephropathy in type 1 diabetes. Diabetes Care. 2004;27:1259-64. [PMID: 15161772] CrossrefMedlineGoogle Scholar22. Khera PK, Joiner CH, Carruthers A, Lindsell CJ, Smith EP, Franco RS, et al. 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Cohen RM, Snieder H, Lindsell CJ, Beyan H, Hawa MI, Blinko S, et al. Evidence for independent heritability of the glycation gap (glycosylation gap) fraction of HbA1c in nondiabetic twins. Diabetes Care. 2006;29:1739-43. [PMID: 16873773] CrossrefMedlineGoogle Scholar27. Paré G, Chasman DI, Parker AN, Nathan DM, Miletich JP, Zee RY, et al. Novel association of HK1 with glycated hemoglobin in a non-diabetic population: a genome-wide evaluation of 14 618 participants in the Women's Genome Health Study. PLoS Genet. 2008;4:1000312. [PMID: 19096518] CrossrefMedlineGoogle Scholar28. Paterson AD, Waggott D, Boright AP, Hosseini SM, Shen E, Sylvestre MP, et al; MAGIC (Meta-Analyses of Glucose and Insulin-related traits Consortium). A genome-wide association study identifies a novel major locus for glycemic control in type 1 diabetes, as measured by both A1c and glucose. Diabetes. 2010;59:539-49. [PMID: 19875614] CrossrefMedlineGoogle Scholar Author, Article, and Disclosure InformationAffiliations: From University of Michigan, Ann Arbor, Michigan 48109; and University of Cincinnati, Cincinnati, OH 45267.Grant Support: By the Michigan Diabetes Research and Training Center, funded by grant DK020572 from the National Institute of Diabetes and Digestive and Kidney Diseases and the U.S. Department of Veterans Affairs (Cincinnati Veterans Affairs Medical Center and Merit Award 5I01CX000121-02).Disclosures: None disclosed. Forms can be viewed at www.acponline.org/authors/icmje/ConflictOfInterestForms.do?msNum=M10-0983.Corresponding Author: William H. Herman, MD, MPH, University of Michigan, 1000 Wall Street, 6th Floor, Ann Arbor, MI 48105-5714; e-mail, [email protected]umich.edu.Current Author Addresses: Dr. Herman: University of Michigan, 1000 Wall Street, 6th Floor, Ann Arbor, MI 48105-5714.Dr. Cohen: University of Cincinnati Medical Center, 3125 Eden Avenue, Cincinnati, OH 45267. 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Brancati, MD, MHSDefinition of PrediabetesA1C Versus Glucose Testing: A ComparisonInsufficient sensitivity of hemoglobin A1C determination in diagnosis or screening of early diabetic statesDoes the Relationship Between Hemoglobin A1c and Mean Glucose Levels Differ by Race?David M. Nathan, MD and Hui Zheng, PhD 15 June 2010Volume 152, Issue 12Page: 815-817KeywordsGeneticsGlucoseGlucose intoleranceGlycationHbA1cHealth surveysHemoglobinIngestionType 2 diabetes ePublished: 15 June 2010 Issue Published: 15 June 2010 CopyrightCopyright © 2010 by American College of Physicians. All Rights Reserved.PDF DownloadLoading ...