Background: Prior investigations regarding glucose variability in nondiabetic subjects measured by continuous glucose monitoring (CGM) have been limited to only few weeks. Little is known about what defines healthy or pathologic glycemic variability. This study investigated “normal glycemia” under daily conditions using a long-term implantable CGM system in nondiabetic adults for 90 days.

Methods: 25 adult nondiabetic participants (10 Male, 15 Female, 17 participants >45 years old) were inserted with the Eversense® CGM System (Senseonics Inc, MD). Participants were instructed to continuously wear the CGM system during the 90 day period and calibrate the system when prompted. Analysis was performed to estimate standardized measures of euglycemia (70-180 mg/dL), hypoglycemia (<54, <70 mg/dL), hyperglycemia (>180, >200 mg/dL) and glucose variability (Mean, SD, CV).

Results: Out of 25 participants, 5 had inadequate data for inclusion. Analysis showed the average glucose value of the nondiabetic participants was 102 mg/dL (SD=18 and CV=0.17). Average percent time spent in hypoglycemia <54mg/dL was 0.14% and <70mg/dL was 1.5%. Time spent in euglycemia 70-180 mg/dL was 98%. Time spent in hyperglycemia >180 and >200 mg/dL was 0.17% and 0.05%, respectively. 17 participants had at least one value < 54mg/dL and 18 participants had glucose values >180mg/dL with 11 subjects with glucose values > 200mg/dL.

Conclusions: Glycemic variability recorded over extended period of time in participants without a diagnosis of diabetes showed similar results as observed by previous researchers over short duration with tight glycemic control. However, hypo- and hyperglycemic excursions are in some normoglycemic regarded individuals more frequent than suggested without CGM. Further analysis including meal challenge and fasting levels may provide guidance regarding expected values for persons without a diagnosis of diabetes and to set realistic target ranges for those with diabetes.


D. Deiss: Consultant; Self; Senseonics. Advisory Panel; Self; Abbott. Consultant; Self; Roche Diabetes Care Health and Digital Solutions. Advisory Panel; Self; Becton, Dickinson and Company. T. Abtahi: Other Relationship; Self; Senseonics. R. Rastogi: Employee; Self; Senseonics. E.L. Kelley: Employee; Self; Senseonics.

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