221-OR: Risk Factors of Severe Hypoglycemia (SH) and Level 2 Hypoglycemia (Lv2Hypo) in Hybrid Closed-Loop (HCL) Users

• Published in: Diabetes (New York, N.Y.) Vol. 74; no. Supplement_1; p. 1
• Main Authors: KUEI LIN, YU, DEVORE, MICAH H., HEPWORTH, EMILY, AGNI, ANNIKA, YE, WEN, FISHER, SIMON J.
• Format: Journal Article
• Language: English
• Published: New York American Diabetes Association 20.06.2025
• Subjects: Diabetes mellitus; Glucose; Hyperglycemia; Hypoglycemia; Risk factors
• ISSN: 0012-1797; 1939-327X
• DOI: 10.2337/db25-221-OR

Introduction and Objective: Despite advancement in diabetes technologies, SH and Lv2Hypo persist in HCL users. We assessed factors related to SH and Lv2Hypo among HCL users with T1D. Methods: From a national cohort of US T1D adult HCL users, a cross-sectional survey assessed six-month SH history, HbA1c, impaired awareness of hypoglycemia (IAH; using Hypoglycemia Awareness Questionnaire) and CGM data. Analyses included logistic regression, t-tests and Chi-square tests. Results: Of 1,092 T1D HCL users (54% female, mean age: 45), IAH and higher HbA1c were related to higher odds of having ≥1 SH episodes (p<0.001). Of 601 subjects with CGM data, IAH, lower HbA1c and higher glucose coefficients of variation (CV) were related to higher odds of having ≥1% of time in Lv2Hypo (p<0.01). Having ≥1% of time in Lv2Hypo was not related to SH. Compared to the subgroup of subjects with neither SH nor ≥1% Lv2Hypo (n=414), subjects with SH only (n=139) presented with more time in hyperglycemia (i.e., glucose >180 mg/dL) and higher HbA1c; subjects with ≥1% of time in Lv2Hypo only (n=33) presented with less time in hyperglycemia and lower HbA1c; subject who experienced both SH and ≥1% of time in Lv2Hypo (n=15) exhibited the worst IAH and highest glucose variability (Fig.). Conclusion: Among HCL users, high IAH and CV are related to both SH and Lv2Hypo. SH and time in Lv2Hypo risk are distinguished by time in hyperglycemia and HbA1c.