Impact of body composition on the accuracy of a Medtronic Guardian continuous glucose monitoring system

Continuous glucose monitoring (CGM) systems are used in therapeutic decisions for diabetes management, however the impact of body composition on CGM accuracy is not known. Body composition variables (body mass index BMI, mid arm circumference, percentage fat and impedance) were collected in an observational study designed to determine the accuracy of an investigational Medtronic Guardiansensor 3. Seven days of sensor glucose data were analysed from 112 participants >7 years of age with mean BMI Z score 0.48 (< 18 years) and BMI 26.7 (≥18 years). The outcome was the weighted absolute relative difference (ARD). Data were analysed using generalised estimating equations to account for correlation between repeated measures. No statistically significant associations between measures of body composition and device accuracy were found. Body composition does not have a meaningful impact on the accuracy of CGM systems.