965-P: The Related Factors Affecting the Relationship between HbA1c and Glucose Management Indicator in Adult T2D Patients with Good Glycemic Control

Abstract

Aim: Glucose Management Indicator (GMI) is correlated with HbA1c, while studies reported the discrepancy between them. Factors affecting this discrepancy, especially in patients with good glycemic control, remain unclear. This study was designed to explore the related factors affecting the relationship between HbA1c and GMI in adult T2D patients with good glycemic control. Methods: Adult T2D patients with good glycemic control who received HbA1c test and CGM were retrospectively analyzed. GMI and glycemic variability (GV) indices including SD and MAGE were derived from CGMS. The absolute value of hemoglobin glycation index (HbA1c minus GMI) (|HGI|) was used to quantify the difference between HbA1c and GMI. Linear regression and correlation analyses were used to analyze the correlation between GV indices and |HGI|, HbA1c and GMI and whether GV affected their relationship. Results: Eighty-four patients (median HbA1c 6.6%, median GMI 6.4%) were included. |HGI| was higher than 0.5% in 40% of the patients (n=34). |HGI| was linearly correlated with SD and MAGE (β = 0.291 and 0.294, P<0.05). HbA1c was linearly correlated with GMI (β=0.525, P<0.001). This correlation remained after adjusting for sex, age, diabetes course, BMI, hemoglobin level and with chronic diabetic complications or not (Model 1, β=0.496, P<0.001). Further adjusting for SD (Model 2) or MAGE (Model 3) based on Model 1, the correlation between HbA1c and GMI became weaker (β=0.398 and 0.425, respectively). The correlation between HbA1c and GMI was closer in the patients with normal SD (<1.4mmol/L) than those with abnormal SD (r=0.563 vs. r=0.505). A similar result could be found in patients with normal MAGE (<3.9mmol/L) and abnormal MAGE (r=0.579 vs. r=0.514). Conclusion: HbA1c was positively correlated with GMI. But even in adult T2D patients with good glycemic control, the correlation between HbA1c and GMI was significantly affected by GV. SD or MAGE accounted for this discrepancy. Disclosure Z.Liu: None. B.Lin: None. D.Chen: None. H.Lin: None. D.Yang: None. J.Yan: None. B.Yao: None. W.Xu: None.