Systematic Review of Continuous Glucose Monitor Accuracy in the Hypoglycemia Range for Non-Critical Care Ward Hospitalized People Living With Diabetes

In-hospital standard of care for people living with diabetes (PLWD) is based on capillary blood glucose to activate hypoglycemia treatment protocols. PLWD on non-critical care wards often prefer to keep their continuous glucose monitor (CGM) on for their sense of agency. This systematic review assessed the CGM accuracy in the hypoglycemic range for these PLWD. Databases were searched from 2012 to August 2025. We included studies of adult PLWD on non-critical care wards, with CGM levels below 70 mg/dL (3.9 mmol/L) that were compared with paired reference blood glucose levels. Nine included studies reported on 465 hypoglycemic CGM and reference blood glucose pairs. The mean and median absolute relative differences ranged from 7.6% to 53.3%, and from 11.7% to 38.5%, respectively. The methods for pairing CGM with reference blood glucose varied. In eight studies, the mean absolute relative differences between hypoglycemia range CGM and paired reference blood glucose results were greater than 15%. These high mean absolute relative differences suggest that hypoglycemic range CGM results are too inaccurate to guide in-hospital diabetes therapy.