Correlation between short- and mid-term hemoglobin A1c and glycemic control determined by continuous glucose monitoring

Jen-Hung Huang; Yung-Kuo Lin; Ting-Wei Lee; Han-Wen Liu; Yu-Mei Chien; Yu-Chun Hsueh; Ting-I Lee; Yi-Jen Chen

doi:10.1186/s13098-021-00714-8

Correlation between short- and mid-term hemoglobin A1c and glycemic control determined by continuous glucose monitoring

Diabetol Metab Syndr. 2021 Sep 6;13(1):94. doi: 10.1186/s13098-021-00714-8.

Authors

Jen-Hung Huang^{1

2}, Yung-Kuo Lin^{1

2

3}, Ting-Wei Lee^{4

5}, Han-Wen Liu⁵, Yu-Mei Chien⁵, Yu-Chun Hsueh⁵, Ting-I Lee^{6

7

8}, Yi-Jen Chen^{1

3

9}

Affiliations

¹ Division of Cardiovascular Medicine, Department of Internal Medicine, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan.
² Division of Cardiology, Department of Internal Medicine, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.
³ Cardiovascular Research Center, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan.
⁴ Division of Endocrinology and Metabolism, Department of Internal Medicine, School of Medicine, College of Medicine, Taipei Medical University, 111 Xinglong Road, Section 3, Wenshan District, Taipei, 11696, Taiwan.
⁵ Division of Endocrinology and Metabolism, Department of Internal Medicine, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan.
⁶ Division of Endocrinology and Metabolism, Department of Internal Medicine, School of Medicine, College of Medicine, Taipei Medical University, 111 Xinglong Road, Section 3, Wenshan District, Taipei, 11696, Taiwan. agleems29@gmail.com.
⁷ Division of Endocrinology and Metabolism, Department of Internal Medicine, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan. agleems29@gmail.com.
⁸ Department of General Medicine, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan. agleems29@gmail.com.
⁹ Graduate Institute of Clinical Medicine, Taipei Medical University, Taipei, Taiwan.

Abstract

Background: Glucose monitoring is vital for glycemic control in patients with diabetes mellitus (DM). Continuous glucose monitoring (CGM) measures whole-day glucose levels. Hemoglobin A1c (HbA1c) is a vital outcome predictor in patients with DM.

Methods: This study investigated the relationship between HbA1c and CGM, which remained unclear hitherto. Data of patients with DM (n = 91) who received CGM and HbA1c testing (1-3 months before and after CGM) were retrospectively analyzed. Diurnal and nocturnal glucose, highest CGM data (10%, 25%, and 50%), mean amplitude of glycemic excursions (MAGE), percent coefficient of variation (%CV), and continuous overlapping net glycemic action were compared with HbA1c values before and after CGM.

Results: The CGM results were significantly correlated with HbA1c values measured 1 (r = 0.69) and 2 (r = 0.39) months after CGM and 1 month (r = 0.35) before CGM. However, glucose levels recorded in CGM did not correlate with the HbA1c values 3 months after and 2-3 months before CGM. MAGE and %CV were strongly correlated with HbA1c values 1 and 2 months after CGM, respectively. Diurnal blood glucose levels were significantly correlated with HbA1c values 1-2 months before and 1 month after CGM. The nocturnal blood glucose levels were significantly correlated with HbA1c values 1-3 months before and 1-2 months after CGM.

Conclusions: CGM can predict HbA1c values within 1 month after CGM in patients with DM.

Keywords: Continuous glucose monitoring; Diabetes mellitus; Hemoglobin A1c.