Improved Satisfaction While Maintaining Safety and High Time in Range (TIR) with a Medtronic Investigational Enhanced-Advanced Hybrid Closed Loop System (e-AHCL)

Objective: To determine feasibility and compare acceptance of an investigational Medtronic enhanced-Advanced Hybrid Closed Loop (e-AHCL) system in type 1 diabetes adults with earlier iterations.

Research Design and Methods: Non-randomised three-stage (each of twelve weeks) exploratory study comparing e-AHCL (Bluetooth®-enabled MiniMed™ 780G insulin pump with automatic data upload [780G] incorporating an updated algorithm; calibration-free all-in-one disposable sensor; seven-day infusion set) preceded by a Run-in (Non-Bluetooth® 780G [670G V4.0 insulin pump] requiring manual data upload; Guardian Sensor 3 [GS3] requiring calibration; three-day infusion set), Stage 1 (780G; GS3; three-day infusion-set) and Stage 2 (780G; calibration-free Guardian Sensor 4; three-day infusion set). Treatment satisfaction was assessed by Diabetes Technology Questionnaire (DTQ)-current (primary outcome) and other validated treatment satisfaction tools with glucose outcomes by continuous glucose monitoring (CGM) metrics.

Results: Twenty-one of 22 (11 women) participants (baseline HbA1c 6.7% / 50mmol/mol) completed the study. DTQ-current scores favored e-AHCL (123.1 [17.8]) vs. Run-in (101.6 [24.2]), and Stage 1 (110.6 [20.8]) (both p<0.001) but did not differ from Stage 2 (119.4 [16.0]; p=0.271). Diabetes Medication System Rating Questionnaire short-form scores for ‘Convenience and Efficacy’ favored e-AHCL over Run-in and all stages. Percent time in range (TIR) 70-180mg/dL was greater with e-AHCL vs. Run-in and Stage 2 (+2.9% and +3.6% respectively; both p<0.001). Percent time <70mg/dL for e-AHCL were significantly lower than Run-in, Stage 1 and Stage 2 ( -0.9%, -0.6%, and -0.5% respectively; all p<0.01).

Conclusions: e-AHCL was feasible. User satisfaction increased compared with earlier Medtronic HCL iterations without compromising glucose control.