Accuracy and Precision of Flash Glucose Monitoring Sensors Inserted Into the Abdomen and Upper Thigh Compared to the Upper Arm (out of sight)

Nowadays, most Belgian patients with type 1 diabetes use flash glucose monitoring (FreeStyle® Libre™ [FSL]) to check their glucose values, but some patients find the sensor on the upper arm too visible. The aim of this study was to compare accuracy and precision of FSL sensors when placed on different sites. Twenty-three adults with type 1 diabetes used three FSL sensors simultaneously for 14 days on upper arm, abdomen, and upper thigh. FSL measurements were compared to capillary blood glucose (BG) measurements obtained with built-in FSL BG meter. Aggregated mean absolute relative difference was 11.8±12.0%, 18.5±18.4% and 12.3±13.8% for arm, abdomen (p=0.002 vs. arm) and thigh (p=0.5 vs. arm) respectively. Clarke error grid analysis for arm and thigh were comparable (zone A: 84.9% vs. 84.5%, p=0.6), while less accuracy was seen for abdomen (69.4%, p=0.01). Apart from the first day, accuracy of FSL sensors on arm and thigh was more stable across the 14-day wear duration than accuracy of sensors on abdomen, which deteriorated mainly during week two (p<0.0005). Aggregated precision absolute relative difference was markedly lower for arm/thigh (10.9±11.9%) compared to arm/abdomen (20.9±22.8%) (p=0.002). Our results indicate that accuracy and precision of FSL sensors placed on upper thigh are comparable to upper arm, whereas abdomen performed unacceptably poor.

Publication year:2018

BOF-keylabel:yes

IOF-keylabel:yes

BOF-publication weight:3

CSS-citation score:1

Authors from:Government, Hospital, Higher Education

Accessibility:Open