@article{1d039543da9244d887342c2a60fc089c,
title = "Implications of the Hemoglobin Glycation Index on the Diagnosis of Prediabetes and Diabetes",
abstract = "Objective: Fasting plasma glucose (FPG), 2-hour plasma glucose (2hPG) from a 75-g oral glucose tolerance test (OGTT) and glycated hemoglobin (HbA1c) can lead to different results when diagnosing prediabetes and diabetes. The Hemoglobin Glycation Index (HGI) quantifies the interindividual variation in glycation resulting in discrepancies between FPG and HbA1c. We used data from the Vitamin D and Type 2 Diabetes (D2d) study to calculate HGI, to identify HGI-associated variables, and to determine how HGI affects prediabetes and diabetes diagnosis. Measurements: A linear regression equation [HbA1c (%) = 0.0164 × FPG (mg/dL) + 4.2] was derived using the screening cohort (n = 6829) and applied to calculate predicted HbA1c. This was subtracted from the observed HbA1c to determine HGI in the baseline cohort with 2hPG data (n = 3945). Baseline variables plus prediabetes and diabetes diagnosis by FPG, HbA1c, and 2hPG were compared among low, moderate, and high HGI subgroups. Results: The proportion of women and Black/African American individuals increased from low to high HGI subgroups. Mean FPG decreased and mean HbA1c increased from low to high HGI subgroups, consistent with the HGI calculation; however, mean 2hPG was not significantly different among HGI subgroups. Conclusions: High HGI was associated with Black race and female sex as reported previously. The observation that 2hPG was not different across HGI subgroups suggests that variation in postprandial glucose is not a significant source of population variation in HGI. Exclusive use of HbA1c for diagnosis will classify more Black individuals and women as having prediabetes compared with using FPG or 2hPG.",
keywords = "diagnosis, hemoglobin glycation, observational study, oral glucose tolerance test, prediabetes, type 2",
author = "Hsia, {Daniel S.} and Neda Rasouli and Pittas, {Anastassios G.} and Lary, {Christine W.} and Anne Peters and Lewis, {Michael R.} and Kashyap, {Sangeeta R.} and Johnson, {Karen C.} and Leblanc, {Erin S.} and Phillips, {Lawrence S.} and Hempe, {James M.} and Desouza, {Cyrus V.} and Irwin Brodsky and Lisa Ceglia and Chhavi Chadha and Ranee Chatterjee and Bess Dawson-Hughes and Cyruse Desouza and Rowena Dolor and John Foreyt and Adline Ghazi and Sun Kim and Emilia Liao and Saul Malozowski and Neff, {Lisa M.} and Patrick O'neil and Jean Park and Richard Pratley and Philip Raskin and David Robbins and Clifford Rosen and Aroda, {Vanita R.} and Patricia Sheehan and Staten, {Myrlene A.} and Knowler, {William C.}",
note = "Funding Information: The authors thank the D2d investigators, staff, and trial participants for their outstanding dedication and commitment to the study. Dr. Pittas was supported in part by generous donations to the Tupper Research Fund at Tufts Medical Center. Funding Information: Financial Support: The planning phase of D2d was funded by the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) through a multicenter clinical study implementation planning grant (U34) to Tufts Medical Center in Boston, MA (U34DK091958; principal investigator A.G.P.). Planning was also supported in part by the Intramural Research Program of the NIDDK. The conduct of D2d is primarily supported by NIDDK and the Office of Dietary Supplements of the National Institutes of Health through the multicenter clinical study cooperative agreement (U01DK098245; principal investigator A.G.P.) to Tufts Medical Center where the D2d Coordinating Center is based. The U01 grant mechanism establishes the NIDDK project scientist (M.A.S.) as a member of the D2d Research Group. The study also received secondary funding from the American Diabetes Association (1-14-D2d-01). The D2d investigators and the NIDDK project scientist had a role in the design and conduct of the study; interpretation of the data and data collection; management, analysis, review and approval of the manuscript; and the decision to submit the manuscript for publication.",
year = "2020",
month = jan,
day = "8",
doi = "10.1210/clinem/dgaa029",
language = "English (US)",
volume = "105",
journal = "Journal of Clinical Endocrinology and Metabolism",
issn = "0021-972X",
publisher = "The Endocrine Society",
number = "3",
}