Evaluation of subcutaneous glucose monitoring systems under routine environmental conditions in patients with type 1 diabetes

Abstract

We compared the sensor performance of 3 commercially available GM systems. A total of 12 patients with type 1 diabetes were included in a single-centre, open-label study in which the sensor performance of the Abbott FreeStyle libre (Abbott), Dexcom G4 Platinum (Dexcom) and Medtronic MiniMed 640G (Medtronic) systems over 12 hours was compared during mimicked real-life conditions (meals, exercise, hypo-and hyperglycaemia). Sensor performance was determined by fulfilment of ISO 15197:2013 criteria, calculating mean absolute relative difference (MARD), and was also illustrated using Parkes error grid and Bland-Altman plots. Sensor performance during changes in metabolic variables (lactate, betahydroxybutyrate, glucagon, non-esterified-fatty-acids) was determined by Spearman's rank correlation coefficient testing. The systems fulfilled ISO 15197:2013 criteria by 73.2% (Abbott), 56.1% (Dexcom) and 52.0% (Medtronic). The MARDs AE standard deviation in the entire glycaemic range were 13.2% AE 10.9% (Abbott), 16.8% AE 12.3% (Dexcom) and 21.4% AE 17.6% (Medtronic), respectively. All sensors performed less accurately during hypoglycaemia and best during hyperglycaemia. We did not observe an influence of metabolic variables on sensor performance.

Impact of physical exercise on sensor performance of the FreeStyle Libre intermittently viewed continuous glucose monitoring system in people with Type 1 diabetes: a randomized crossover trial

“…Our results are in contrast to findings from a previous study by our research team, which determined the iCGM system to be accurate during exercise testing, with a MARD of 8.7AE5.9% and a Parks error grid of 100% for values in zone A [5]. Our results are in contrast to findings from a previous study by our research team, which determined the iCGM system to be accurate during exercise testing, with a MARD of 8.7AE5.9% and a Parks error grid of 100% for values in zone A [5].…”

Accuracy of flash glucose monitoring in insulin‐treated patients with type 2 diabetes

“…We found that glucose levels measured by FGM were slightly lower than those measured in venous blood (−6.5 mg/dL, 30 measurements) and those measured by CGM (−13.6 mg/dL, 1,279 measurements), and this tendency was similar to the results of earlier studies. Aberer et al .…”

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]. These observations strongly suggest that values obtained from FGM should be examined in a clinical context.…”