Trials of continuous glucose monitors (CGMs) and hybrid closed-loop systems (HCLS) demonstrate improvements in glycemia with reductions in hypoglycemia in T1D, but there is limited real-world data on how these technologies impact the prevalence of impaired awareness of hypoglycemia (IAH) , severe hypoglycemic events (SHEs) , and glycemic control. We conducted a one-time online survey of adults with T1D in the T1D Exchange Registry and online communities. Self-reported medical histories (insulin delivery method, HbA1c, IAH, SHEs) and CGM data were collected. 2044 patients (mean age 43 y, mean T1D duration 26 y, 72% female, 95% White) completed the survey. Most reported using CGMs (92%) ; 953 also used HCLS. Mean HbA1c was 6.89%; 41.5% had an HbA1C of ≥7%; 30.7% reported IAH; 19.8% had ≥1 SHE in the prior year; 12.0% had ≥2 SHEs in the prior year; 9.6% had IAH + ≥1 SHE; and 6.6% had IAH + ≥2 SHEs (Table) . Rates of SHEs and IAH + SHEs were lower in CGM users and CGM + HCLS users than in non-CGM users; however, among CGM + HCLS users, 16.6% reported ≥1 SHE, 8.7% ≥2 SHEs, 7.8% IAH + ≥1 SHE, and 4.7% IAH + ≥2 SHEs. Also, 35.6% of CGM + HCLS users had an HbA1C of ≥7%. In a patient cohort with high rates of technology adoption, rates of SHEs and IAH remained high, with a significant proportion of patients not achieving targeted glycemic control, indicating the need for novel T1D treatments.


J. Pettus: Advisory Panel; Lilly, MannKind Corporation, Novo Nordisk, Sanofi. Consultant; Carmot Therapeutics, Inc., Diasome. L. Titievsky: Employee; Intercept Pharmaceuticals, Inc., Pfizer Inc., Vertex Pharmaceuticals Incorporated. Stock/Shareholder; Intercept Pharmaceuticals, Inc., Pfizer Inc., Vertex Pharmaceuticals Incorporated. K. Hagan: Employee; Vertex Pharmaceuticals Incorporated. T. Liu: Employee; Takeda Pharmaceutical Company Limited, Vertex Pharmaceuticals Incorporated. Stock/Shareholder; Seattle Genetics, Inc. K. Chandarana: Employee; Vertex Pharmaceuticals Incorporated. J.L. Gaglia: Advisory Panel; Dompé, Regeneron Pharmaceuticals Inc. Consultant; Vertex Pharmaceuticals Incorporated. Research Support; Avotres Inc., Dompé, Janssen Research & Development, LLC, Provention Bio, Inc. Stock/Shareholder; Vertex Pharmaceuticals Incorporated. W. Wolf: None. J. Bispham: Employee; PPD Inc., T1D Exchange. K.S.M. Chapman: None. D. Finan: None. J. Sherr: Advisory Panel; Bigfoot Biomedical, Inc., Cecelia Health, Insulet Corporation, Medtronic, Vertex Pharmaceuticals Incorporated. Consultant; Insulet Corporation, Lexicon Pharmaceuticals, Inc. Research Support; Dexcom, Inc., Insulet Corporation, Jaeb Center for Health Research, JDRF, Medtronic, National Institute of Diabetes and Digestive and Kidney Diseases. Speaker's Bureau; Lilly Diabetes.

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