The Accuracy of Continuous Glucose Sensors in People with Diabetes Undergoing Hemodialysis (ALPHA Study)

Abstract

Objectives: Real-time and intermittently scanned continuous glucose monitoring are increasingly used for glucose monitoring in people with diabetes requiring renal replacement therapy, with limited data reporting their accuracy in this cohort. We evaluated the accuracy of Dexcom G6 and Abbott Freestyle Libre 1 glucose monitoring systems in people with diabetes undergoing hemodialysis. Methods: Participants on hemodialysis with diabetes (on insulin or sulfonylureas) were recruited. Paired sensor glucose from Dexcom G6 and Freestyle Libre 1 were recorded with plasma glucose analyzed using the Yellow Springs Instrument (YSI) method at frequent intervals during hemodialysis. Analysis of accuracy metrics included mean absolute relative difference (MARD), Clarke error grid (CEG) analysis and proportion of CGM values within 15% and 20% or 15 and 20 mg/dL of YSI reference values for blood glucose >100 or ≤100 mg/dL, respectively (% 15/15, % 20/20). Results: Forty adults (median age 64.7 [60.2-74.4] years) were recruited. Overall MARD for Dexcom G6 was 22.7% (2656 matched glucose pairs), and 11.3% for Libre 1 (n = 2785). The proportions of readings meeting %15/15 and %20/20 were 29.1% and 45.4% for Dexcom G6, respectively, and 73.5% and 85.6% for Libre 1. CEG analysis showed 98.9% of all values in zones A and B for Dexcom G6 and 99.8% for Libre 1. Conclusions: Our results indicate Freestyle Libre 1 is a reliable tool for glucose monitoring in adults on hemodialysis. Further studies are required to evaluate Dexcom G6 accuracy in people on hemodialysis.

Keywords: Accuracy; Continuous glucose monitoring; Diabetes; End-stage kidney disease; Hemodialysis; Intermittently scanned continuous glucose monitoring; Mean absolute relative difference.