Performance of the FreeStyle Libre Flash glucose monitoring system in patients with type 1 and 2 diabetes mellitus

Abstract

ObjectiveTo evaluate the performance of the FreeStyle Libre Flash continuous glucose monitoring (FSL-CGM) system against established central laboratory methods.Research design and methods20 subjects (8 type 1 diabetes mellitus, 12 type 2 diabetes mellitus) were analyzed. FSL-CGM sensor measurements (inserted in arm and abdomen) were compared with capillary blood glucose results analyzed with StatStrip as semigold standard. The glucose response after a standardized oral glucose load was measured by FSL-CGM and capillary samples analyzed by perchloric acid hexokinase (PCA-HK) method, StatStrip and FSL test strip (FSLC), and a commonly used CGM system (iPro2).ResultsFSL-CGM arm sensor readings showed 85.5% of paired readings falling within Clarke Error Grid (ISO 15197:2013) zone A when compared with StatStrip. For FSL-CGM abdomen and FSLC, these percentages were 64% and 98%, respectively. The overall correlation of FSL-CGM in the arm and the StatStrip indicates a performance with lower results with the FSL-CGM in the arm than expected based on the StatStrip in the lower glucose ranges, and higher results than expected in the higher ranges. Following a standardized glucose load, a slower rise in glucose level was observed for FSL-CGM arm as compared with PCA-HK, StatStrip, FSLC, and iPro2 during the first 45–60 min after glucose load ingestion.ConclusionsCertain matters need attention while using the FSL-CGM in daily life including the observed lower values in the lower ranges, and the underestimation of the effect of a meal on glucose response. These effects of such deviations can partly be overcome by optimizing the available user instructions.Trial registration numberTC5348; results.

Evaluation of the FreeStyle® Libre Flash Glucose Monitoring System in Children and Adolescents with Type 1 Diabetes

“…It has been shown that in lower glucose ranges and during hypoglycaemia, CGM devices are less accurate [34, 38, 39] and results are usually expressed as MAD. When the capillary BG values were < 70 mg/dL, the MAD in our study was 13.7 mg/dL, which is comparable with the findings of other studies reporting MAD values between 12.3 and 13.4 mg/dL [20, 35, 37]. Hence, it remains of utmost importance to confirm sensor-reported hypoglycaemia or impending hypoglycaemia by capillary BG control.…”

“…Szadkowska et al [27] studied the FGM in 78 children and found that 99.1% of the results fell in zone A and B. In adults, Baily et al [20], found 99.7% and Fokkert et al [35] found 99.8% of the results in zone A and B. It is noteworthy to mention that Edge et al [25] and Baily et al [20] compared the scanned SG values with the capillary BG levels determined by the build-in meter using FreeStyle Optium test strips.…”

“…In children, Edge et al [25] reported a MARD of 13.9% and Szadkowska et al [27] observed a MARD of 13.5%. In adults, MARDs of 11.4% (12% compared with the YSI reference) [20], of 13.2% [37], and of 10–17% [35] have been reported. As reported in other studies, the MARD was higher in the hypoglycaemic range (23.7%) than in the normoglycaemic range (17.4%) and hyperglycaemic range (13.6%).…”

“…Szadkowska et al [27] used the Contour Plus One glucometer. Fokkert et al [35] compared the SG values with the StatStrip POC glucose measurement systems. In our study 76.2% of the hypoglycaemias and 93.8% of the hyperglycaemias were detected by the FGM.…”

Careful readings for a flash glucose monitoring system in nondiabetic Japanese subjects: individual differences and discrepancy in glucose concentrarion after glucose loading [Rapid Communication]

“…Furthermore, 75-g OGTT resulted in a slower rise in glucose level as determined by FGM than that obtained by the perchloric acid hexokinase method, POC testing, test strip, and conventional CGM during the first 45-60 minutes after glucose loading [11]. Moreover, a study using CGM including FGM for type 1 diabetes patients indicated that all sensors performed less accurately during hypoglycemia and best during hyperglycemia [12].…”