Endocrine Abstracts

Introduction: Although the use of technology in type 1 diabetes (T1D) has been shown to improve fear and perception of hypoglycemia and continuous glucose monitoring (CGM) metrics, their underlying associations remain unclear. This study examines the correlations between fear and perception of hypoglycemia and CGM-measured time in hypoglycemia along with other CGM-metrics.

Methods: This retrospective secondary-use study assessed correlations between 12-month changes in questionnaires scores and 12-month changes in CGM-metrics in 1370 adults with T1D who used either real-time CGM (rtCGM; ALERTT1-study (1), n = 254) or hybrid closed-loop (HCL; INRANGE-study (2), n = 1116). Questionnaires included the Hypoglycemia Fear Survey II (HFS) and the perceived frequency of hypoglycemia item from the Diabetes Treatment Satisfaction Questionnaire - status (DTSQs-hypo). Delta (Δ) represents the change from baseline to 12 months after rtCGM or HCL initiation. Data are reported as mean ± SD.

Results: Mean age was 41.0 ± 13.7 years, 55.9% were female. At baseline, HbA1c was 7.6 ± 1.0%, time in range (TIR; 70-180 mg/dl) 61.1 ± 15.5%, time <70 mg/dl 3.4 ± 3.5% and time <54 mg/dl 0.8 ± 1.4%. Delta HFS-worry scores were not correlated with Δtime <70 mg/dl (r = 0.037, P = 0.240) or Δtime <54 mg/dl (r = 0.012, P = 0.708). Similarly, ΔHFS-behavior showed no correlation with Δtime <70 mg/dl (r = -0.036, P = 0.257) and only very weak correlation with Δtime <54 mg/dl (r = -0.071, P = 0.025). For other CGM-metrics only weak or no correlations were found with ΔHFS-worry, including Δtime >250 mg/dl (r = 0.067, P = 0.033) and Δcoefficient of variation (r = 0.092, P = 0.005). Similarly, ΔHFS-behavior showed only very weak correlation with ΔTIR (r = -0.081, P = 0.010) and Δtime in tight range [70-140 mg/dl] (r = -0.068, P = 0.040). Also ΔDTSQs-hypo showed only weak correlations with Δtime <70 mg/dl (r = 0.188, P <0.001) and Δtime <54 mg/dl (r = 0.115, P <0.001)

Conclusion: No clear correlations were found between changes in fear and perception of hypoglycemia and CGM-metrics, suggesting that factors beyond glucose management alone likely contribute to these psychological responses in adults using rtCGM or HCL over a one-year period.

References: 1. Visser MM, Charleer S, Fieuws S, De Block C, Hilbrands R, Van Huffel L, et al. Effect of switching from intermittently scanned to real-time continuous glucose monitoring in adults with type 1 diabetes: 24-month results from the randomised ALERTT1 trial. doi: 10.1016/S2213-8587(22)00352-7, 96-108 (2023). 2. De Meulemeester J, Keymeulen B, De Block C, Van Huffel L, Taes Y, Ballaux D, et al. One-year realworld benefits of Tandem Control-IQ technology on glucose management and person-reported outcomes in adults with type 1 diabetes: a prospective observational cohort study. doi: 10.1007/s00125-025-06366-x, 948-960 (2025).

Keywords: Type 1 diabetes, hypoglycemia, continuous glucose monitoring