Continuous glucose monitoring-derived time in range is associated with changes in arterial stiffness in type 2 diabetes.

BACKGROUND: Current guidelines recommend continuous glucose monitoring (CGM) to complement HbA1c in glycemic assessment. While cross-sectional studies have reported associations between CGM-derived metrics and arterial stiffness in type 2 diabetes (T2D), longitudinal evidence remains limited. OBJECTIVE: This study aimed to investigate the longitudinal associations of CGM metrics, particularly time in range (TIR) and coefficient of variation (CV), with changes in brachial-ankle pulse wave velocity (baPWV). METHODS: This exploratory study analyzed data collected over 260 weeks from an ongoing prospective, multicenter, observational cohort. A total of 348 participants with type 2 diabetes and no history of symptomatic cardiovascular disease underwent baPWV measurements at baseline, 104 weeks, and/or 260 weeks. Participants were divided into two groups based on the median values of CGM-derived metrics and HbA1c at baseline, and the associations between each baseline value and longitudinal changes in baPWV were evaluated using mixed-effects models for repeated measures, adjusting for conventional atherosclerotic risk factors. RESULTS: The median change in baPWV from baseline was 60.1 cm/s (95% CI: 34.6 to 85.6) at 104 weeks and 130.3 cm/s (95% CI: 98.6 to 162.1) at 260 weeks (p < 0.001). The change over time in baPWV differed between the higher and lower TIR groups, with a significant interaction between group and time (p = 0.013) in the multivariable-adjusted model. This interaction remained significant even after further adjustment for HbA1c (p = 0.013). In contrast, baseline CV, other CGM-derived metrics, and HbA1c were not associated with longitudinal changes in baPWV. CONCLUSIONS: TIR was significantly associated with longitudinal changes in arterial stiffness in participants with type 2 diabetes, independent of HbA1c.