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A1C: Recommendations, Debates, and Questions

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Bloomgarden, Zachary T.·2009·Diabetes Care
DOI 10.2337/dc09-zb12PMC PMC6898901
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Abstract

A series of elegant investigations some 4 decades ago led to the realization that elevated levels of certain hemoglobin components are found in individuals with diabetes (1).The useful measurement of A1C became standard in assessment of glycemia (2).A1C, rather than direct measures of glycemia, is now used as the "goal" for diabetes treatment (3,4). Should A1C be used for diabetes diagnosis?At the 69th Scientific Sessions of the American Diabetes Association (ADA), David Nathan (Boston, MA) discussed the role of A1C in the diagnosis of diabetes in nonpregnant subjects and explained the position advocated by an expert committee of ADA and the European Association for the Study of Diabetes (EASD) that the diagnosis of diabetes may be conveniently based on A1C Ն6.5%, without the need to measure a plasma glucose concentration (5).All methods previously used for the diagnosis of diabetes, he noted, have relied on measuring blood glucose, whether in the fasting state or after a stress, as in the oral glucose tolerance test.He asserted that early attempts to establish the diagnosis of diabetes were hampered by absence of standardization, for example, with different times for blood determination or with different oral glucose loads.Type 1 diabetes usually has characteristic presentation and thus is easily diagnosed, but Nathan observed that type 2 diabetes can be subtle in its onset; analyses of fasting and 2-h postload glucose levels in Korea, Nauru, Egypt, and Taiwan showed unimodal glucose distributions (6), although this may be an artifact of the relative infrequency of dia-

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  • A1C testing is readily available in the U.S., relatively well standardized, exhibits low intraindividual variation, and does not require fasting or restriction to certain times of the day.

    “Because A1C testing is readily available in the U.S., is relatively well standardized, exhibits low intraindividual variation, and does not require fasting or restriction to certain times of the day (6), many clinicians might wish to use A1C measurements to screen for diabetes and pre-diabetes.”

    From Screening for Diabetes and Pre-Diabetes With Proposed A1C-Based Diagnostic Criteria (2010) · cites this paper as [6]

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Research works printed but not linked: 39

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Authors
Bloomgarden, Z. T.
Affiliations
Icahn School of Medicine at Mount Sinai (US)
Corresponding author
Bloomgarden, Zachary T.
ORCID
Bloomgarden, Zachary T.
Venue
Diabetes Care
Publisher
American Diabetes Association
Published
2009-12-01
Volume
32
Issue
12
Pages
e141-e147
ISSN
  • 0149-5992 (ISSN-L)
  • 1935-5548
DOI
10.2337/dc09-zb12
PMC
PMC6898901
OpenAlex
W2151513100
Cited by
66
References
10
Citations by year
2026: 1 · 2024: 2 · 2023: 2 · 2022: 1 · 2020: 2 · 2019: 3 · 2018: 3 · 2017: 3 · 2016: 1 · 2015: 6 · 2014: 2 · 2013: 8 · 2012: 8
FWCI
7.77
Type
journal article
Language
en
Open access
Licence
cc-by-nc-nd
Locations
  • Diabetes Care (publishedVersion, cc-by-nc-nd)
  • Europe PMC (PubMed Central) (publishedVersion, cc-by-nc-nd)
  • PubMed Central (publishedVersion, cc-by-nc-nd)
  • PubMed (publishedVersion)
Funders
  • Eli Lilly and Company
  • Dainippon Sumitomo Pharma
  • Novo Nordisk
  • Daiichi Sankyo Europe
Topics
  • Health Sciences › Medicine › Endocrinology, Diabetes and Metabolism › Diabetes Management and Research
  • Health Sciences › Medicine › Endocrinology, Diabetes and Metabolism › Diabetes, Cardiovascular Risks, and Lipoproteins
  • Health Sciences › Medicine › Endocrinology, Diabetes and Metabolism › Diabetes Treatment and Management
Keywords
HbA1c, diabetes diagnosis, glycemic control, type 2 diabetes, type 1 diabetes, diagnostic criteria, plasma glucose, oral glucose tolerance test, fasting blood glucose
MeSH terms
Blood Glucose, Diabetes Mellitus, Glycated Hemoglobin, Humans, Reproducibility of Results, Biomarkers, Glucose Intolerance, Diabetes Complications

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