• 1
    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: 417420.
  • 2
    Gabbay KH, Hasty K, Breslow JL, Ellison RC, Bunn HF, Gallop PM. Glycosylated hemoglobins and long-term blood glucose control in diabetes mellitus. J Clin Endocrinol Metab 1977; 44: 859864.
  • 3
    The Diabetes Control and Complications Trial Research Group. The effect of intensive treatment of diabetes on the development and progression of long-term complications in insulin-dependent diabetes mellitus. N Engl J Med 1993; 329: 977986.
  • 4
    Riddle MC, Ambrosius WT, Brillon DJ, Buse JB, Byington RP, Cohen RM et al. Epidemiologic relationships between A1C and all-cause mortality during a median 3.4-year follow-up of glycemic treatment in the ACCORD trial. Diabetes Care 2010; 33: 983990.
  • 5
    Patel A, MacMahon S, Chalmers J, Neal B, Billot L, Woodward M et al. Intensive blood glucose control and vascular outcomes in patients with type 2 diabetes. N Engl J Med 2008; 358: 25602572.
  • 6
    IDF. Clinical Guidelines Task Force. Global Guideline for Type 2 Diabetes. Brussels: International Diabetes Federation, 2005.
  • 7
    The International Expert Committee. International Expert Committee Report on the role of the A1C Assay in the diagnosis of diabetes. Diabetes Care 2009; 32: 13271334.
  • 8
    American Diabetes Association. Diagnosis and classification of diabetes mellitus. Diabetes Care 2009; 33: S62S69.
  • 9
    WHO. Use of Glycated Haemoglobin (HbA1c) in the Diagnosis of Diabetes Mellitus. Abbreviated Report of a WHO Consultation. Geneva: World Health Organization, 2011.
  • 10
    The Expert Committee on the Diagnosis and Classification of Diabetes Mellitus. Report of the expert committee on the diagnosis and classification of diabetes mellitus. Diabetes Care 1997; 20: 11831197.
  • 11
    Cheng YJ, Gregg EW, Geiss LS, Imperatore G, Williams DE, Zhang X et al. Association of A1C and fasting plasma glucose levels with diabetic retinopathy prevalence in the US population: implications for diabetes diagnostic thresholds. Diabetes Care 2009; 32: 20272032.
  • 12
    Rohlfing C, Wiedmeyer HM, Little R, Grotz VL, Tennill A, England J et al. Biological variation of glycohemoglobin. Clin Chem 2002; 48: 11161118.
  • 13
    Cohen RM, Smith EP. Frequency of HbA1c discordance in estimating blood glucose control. Curr Opin Clin Nutr Metab Care 2008; 11: 512517.
  • 14
    Herman WH, Ma Y, Uwaifo G, Haffner S, Kahn SE, Horton ES et al. Differences in A1C by race and ethnicity among patients with impaired glucose tolerance in the diabetes prevention program. Diabetes Care 2007; 30: 24532457.
  • 15
    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: 770777.
  • 16
    Bleyer AJ, Hire D, Russell GB, Xu J, Divers J, Shihabi Z et al. Ethnic variation in the correlation between random serum glucose concentration and glycated haemoglobin. Diabet Med 2009; 26: 128133.
  • 17
    Jorgensen ME, Bjerregaard P, Borch-Johnsen K, Witte D. New diagnostic criteria for diabetes: is the change from glucose to HbA1c possible in all populations? J Clin Endocrinol Metab 2010; 95: E333E336.
  • 18
    Christensen DL, Witte DR, Kaduka L, Jorgensen ME, Borch-Johnsen K, Mohan V et al. Moving to an A1C-based diagnosis of diabetes has a different impact on prevalence in different ethnic groups. Diabetes Care 2010; 33: 580582.
  • 19
    Mohan V, Vijayachandrika V, Gokulakrishnan K, Anjana RM, Ganesan A, Weber MB et al. A1C cut points to define various glucose intolerance groups in Asian Indians. Diabetes Care 2010; 33: 515519.
  • 20
    Zhou X, Pang Z, Gao W, Wang S, Zhang L, Ning F et al. Performance of an A1C and fasting capillary blood glucose test for screening newly diagnosed diabetes and pre-diabetes defined by an oral glucose tolerance test in Qingdao, China. Diabetes Care 2010; 33: 545550.
  • 21
    Wild S, Roglic G, Green A, Sicree R, King H. Global prevalence of diabetes: estimates for the year 2000 and projections for 2030. Diabetes Care 2004; 27: 10471053.
  • 22
    IDF. IDF Diabetes Atlas. 4th edn. Brussels: International Diabetes Federation, 2009.
  • 23
    Ministry of Health. N ational Health Survey 2004 Singapore. Singapore: Ministry of Health, 2004: 510.
  • 24
    Hughes K, Yeo PP, Lun KC, Thai AC, Wang KW, Cheah JS. Obesity and body mass indices in Chinese, Malays and Indians in Singapore. Ann Acad Med Singapore 1990; 19: 333338.
  • 25
    Tan CE, Emmanuel SC, Tan BY, Jacob E. Prevalence of diabetes and ethnic differences in cardiovascular risk factors. The 1992 Singapore National Health Survey. Diabetes Care 1999; 22: 241247.
  • 26
    Hughes K, Aw TC, Kuperan P, Choo M. Central obesity, insulin resistance, syndrome X, lipoprotein(a), and cardiovascular risk in Indians, Malays, and Chinese in Singapore. J Epidemiol Community Health 1997; 51: 394399.
  • 27
    Cutter J, Tan BY, Chew SK. Levels of cardiovascular disease risk factors in Singapore following a national intervention programme. Bull World Health Organ 2001; 79: 908915.
  • 28
    Nang EE, Khoo CM, Tai ES, Lim SC, Tavintharan S, Wong TY et al. Is there a clear threshold for fasting plasma glucose that differentiates between those with and without neuropathy and chronic kidney disease?: the Singapore Prospective Study Program. Am J Epidemiol 2009; 169: 14541462.
  • 29
    Koenig RJ, Peterson CM, Kilo C, Cerami A, Williamson JR. Hemoglobin AIc as an indicator of the degree of glucose intolerance in diabetes. Diabetes 1976; 25: 230232.
  • 30
    Borg R, Kuenen JC, Carstensen B, Zheng H, Nathan DM, Heine RJ et al. Associations between features of glucose exposure and A1C: the A1C-Derived Average Glucose (ADAG) study. Diabetes 2010; 59: 15851590.
  • 31
    Cohen RM, Franco RS, Khera PK, Smith EP, Lindsell CJ, Ciraolo PJ et al. Red cell life span heterogeneity in hematologically normal people is sufficient to alter HbA1c. Blood 2008; 11: 42844291.
  • 32
    Coban E, Ozdogan M, Timuragaoglu A. Effect of iron deficiency anemia on the levels of hemoglobin A1c in non-diabetic patients. Acta Haematol 2004; 112: 126128.
  • 33
    Soranzo N, Sanna S, Wheeler E, Gieger C, Radke D, Dupuis J et al. Common variants at 10 genomic loci influence hemoglobin A(C) levels via glycemic and nonglycemic pathways. Diabetes 2010; 59: 32293239.