Potential misclassification of diabetes and prediabetes in the US: Mismatched HbA1c and glucose in NHANES 2005-2016

• Type of Material: Article
• Authors: Lisa Staimez, Emory University; Lauren M Kipling, Emory University; J. Nina Ham, Emory University; Brian T Legvold, Emory University; Sandra L Jackson, Centers for Disease Control and Prevention, 4770 Buford Hwy NE, Atlanta, GA 30341, USA; Peter Wilson, Emory University; Mary Rhee, Emory University; Lawrence Phillips, Emory University
• Language: English
• Date: 2022-07-01
• Publisher: ELSEVIER IRELAND LTD
• Publication Version: Author Accepted Manuscript (After Peer Review)
• Copyright Statement: Elsevier B.V.
• License: Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International
• Final Published Version (URL): http://dx.doi.org/10.1016/j.diabres.2022.109935
• Title of Journal or Parent Work: DIABETES RESEARCH AND CLINICAL PRACTICE
• Volume: 189
• Start Page: 109935
• End Page: 109935
• Keywords: HEMOGLOBIN GLYCATION INDEX; Endocrinology & Metabolism; HBA(1C); PREDICTOR; GLYCOHEMOGLOBIN STANDARDIZATION PROGRAM; RISK; GLYCEMIC CONTROL; United States; Diagnosis; VARIABILITY; HbA1c; MICROVASCULAR COMPLICATIONS; TOLERANCE; Science & Technology; A(1C); Life Sciences & Biomedicine
• Research Categories: Health Sciences, Medicine and Surgery

Abstract

Aims: To assess the prevalence and clinical implications of “mismatches” between HbA1c and glucose levels in the United States across the life course. Methods: Participants ages 12–79 years from U.S. National Health and Nutrition Examination Survey (NHANES) 2005–2016 without known diagnosis of diabetes and who had a 75 g oral glucose tolerance test were included. Previously undiagnosed diabetes (DM), prediabetes, and normal glucose metabolism (NGM) were defined using American Diabetes Association cut-points. Mismatches were defined by the hemoglobin glycation index (HGI). Results: In 10,361 participants, 5% and 41% had diabetes and prediabetes, respectively, by fasting or 2-hour glucose criteria. By HbA1c criteria, the high HGI tertile consisted of mostly abnormal classification (3% DM, 52% prediabetes) and the low HGI tertile contained mostly normal classification (78% NGM). Across all ages, 15% (weighted: 30 million individuals) had clinically significant mismatches of HGI magnitude ≥+0.5% (i.e., high mismatch) or ≤−0.5% (low mismatch). Mismatch was most common in older adults and non-Hispanic Black participants. Conclusions: Mismatches of clinically significant magnitude could lead to HbA1c-related misdiagnosis or inappropriate management in up to 30 million Americans. Older adults, non-Hispanic Black individuals, and others with high mismatches may benefit from complementing HbA1c with additional diagnostic and management strategies.