Association of time in tight range and 1,5-anhydroglucitol in type 2 diabetes

Abstract

Aims: Among the novel metrics derived from continuous glucose monitoring (CGM), time in tight range (TITR) has gained increasing attention. Our study aimed to investigate the relationship between 1,5-anhydroglucitol (1,5-AG) and TITR in patients with type 2 diabetes. Materials and Methods: This cross-sectional study included 1531 moderately controlled patients with type 2 diabetes on a stable treatment regimen. TITR and time in range (TIR) were measured with CGM. Spearman correlation analysis was used to assess the relationship between serum 1,5-AG and TITR, and the predictive efficacy of serum 1,5-AG for identifying TITR > 50% was evaluated by the receiver operating characteristic curves. Results: The median levels of serum 1,5-AG and glycated haemoglobin A1c (HbA1c) in the total population were 7.4 (4.4, 12.1) μg/mL and 7.0% (6.4%, 7.5%), respectively. The median TITR was 52.0% (32.0%, 69.0%). Spearman correlation analysis showed that serum 1,5-AG was positively correlated with TITR (p < 0.001). The optimal serum 1,5-AG cut-off for TITR >50% was 8.0 μg/mL, with an area under the curve (AUC) of 0.693 (0.667, 0.719). Serum 1,5-AG combined with fasting glucose or 2-hour postprandial glucose further improved the predictive power for identifying TITR > 50% (both p < 0.001). Across all subgroups, serum 1,5-AG showed acceptable predictive accuracy for TITR > 50% (AUCs around 0.700). Conclusions: Serum 1,5-AG was significantly correlated with TITR in patients with type 2 diabetes, with 8.0 μg/mL emerging as a potential cut-off for identifying TITR > 50%.