Advances in continuous
glucose monitoring (CGM) have transformed ambulatory diabetes management. Until
recently, inpatient use of CGM has remained investigational with limited data
on its accuracy in the hospital setting.
Methods: To analyze the
accuracy of Dexcom G6 CGM, we compared retrospective matched-pair CGM
and capillary point-of-care (POC) glucose data from three inpatient CGM studies
(two interventional and one observational) in general medicine and surgery
patients with diabetes treated with insulin. Analysis of accuracy metrics
included mean absolute relative difference (MARD), median absolute relative difference
(ARD), and proportion of CGM values within ±15, 20 and 30% or ±15, 20 and 30
mg/dL of POC reference values for blood glucose >100 mg/dL or ≤100 mg/dL,
respectively (?/15, /20, 0/30). Clinical reliability was assessed using
Clarke error grid analyses.
Results: A total of 218
patients were included (96% with type 2 diabetes) with a mean age of 60.6 ±
The overall MARD (n=4,067 matched glucose pairs) was 12.8%
and median ARD was 10.1% [IQR 4.6, 17.6]. The proportion of readings meeting
?/15, /20 and 0/30 criteria were 68.7, 81.7, and 93.8%. Clarke error
grid analysis showed 98.7% of all values in zones A+B. MARD and median ARD were higher in
hypoglycemia (<70mg/dL) and severe anemia (hemoglobin <7g/dL).
Conclusion: Our results
indicate that CGM technology is a reliable tool for hospital use and may help
improve glucose monitoring in non-critically ill hospitalized patients with
GMD is supported by the National Institutes of Health (NIH) under Award Number 1K23DK122199-01A1 and has received research support to Emory University from Insulet Corporation. EKS is supported in part by the VA MERIT award (#1I01CX001825) from the United States (U.S.) Department of Veterans Affairs Clinical Sciences Research and Development Service and has received unrestricted research support from Dexcom (to Baltimore VA Medical Center and to University of Maryland) to conduct clinical trials. RJG has received unrestricted research support to Emory for investigator-initiated studies from Novo Nordisk and Dexcom, and consulting fees from Abbott Diabetes Care, Sanofi, Novo Nordisk, Eli Lilly, and Valeritas. RJG is partially supported by research grants from NIH/NIDDK P30DK11102 and 1K23DK123384-01. PV is supported in part by NIH grant 1K23DK113241 and has received consulting fees from Merck and Boehringer-Ingelheim. FJP is supported in part by NIH grants 1K23GM128221-03, P30DK111024-05, and P30DK111024-05S, and has received research support from Merck and Dexcom, and consulting fees from Boehringer Ingelheim. GEU is partly supported by research grants from the NIH/NATS UL1 TR002378 and 1P30DK111024-05, and P30DK111024-05S and has received unrestricted research support from Astra Zeneca, Novo Nordisk, and Dexcom. Two studies included in this analysis were investigator-initiated studies supported by Dexcom.