Background: There are no published studies assessing the accuracy of the FreeStyle Libre CGM in the inpatient management of patients with type 2 diabetes (T2D).

Methods: Adult patients (n: 81) on basal-bolus insulin therapy with a target BG between 70-180 mg/dl were monitored with POC before meals and bedtime and by CGM. The primary outcome was the mean amplitude relative difference (MARD) between matched glucose pairs obtained from POC and CGM.

Results: Among 1453 pairs, the overall MARD was 14.4%. The overall percentage of glucose values within ±15% or 15mg/dl, ±20% or 20mg/dl, and ±30% or 30mg/dl of the POC reference value was 63%, 78%, and 92%, respectively. Clarke Error Grid analysis showed acceptable clinical accuracy with 98.0% of glucoses falling into Zones A (76.8%, n: 1,116) and B (22.0%, n: 320). Accuracy was lower for glucoses < 80 mg/dL (Table 1), however; there were limited matched glucose pairs in hypoglycemic range.

Conclusions: FreeStyle Libre CGM showed an overall satisfactory performance in hospitalized patients, with lower accuracy observed for glucoses < 80 mg/dL. Larger inpatient studies are needed to confirm its accuracy in non-critically ill hospitalized patients.

*Proportion of CGM values within ±15%/±15 mg/dL of POC glucose values, and the analogous %20/20, %30/30


R.J. Galindo: Advisory Panel; Self; Abbott, Novo Nordisk Inc., Sanofi US. Research Support; Self; Novo Nordisk Inc. M.A. Urrutia: None. G. Davis: None. A. Khowaja: None. B.S. Albury: None. I. Anzola: None. A.A. Johnson: None. P. Vellanki: Consultant; Self; Boehringer Ingelheim Pharmaceuticals, Inc., Merck & Co., Inc. Research Support; Self; National Institutes of Health. S. Cardona: None. M. Fayfman: None. A. Migdal: None. C. Zambrano: None. L. Peng: None. F.J. Pasquel: Consultant; Self; Boehringer Ingelheim Pharmaceuticals, Inc., Merck & Co., Inc. G.E. Umpierrez: Advisory Panel; Self; Boehringer Ingelheim Pharmaceuticals, Inc., Janssen Pharmaceuticals, Inc. Research Support; Self; AstraZeneca, Merck & Co., Inc., Novo Nordisk Inc., Sanofi US.



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