Improved Glycemic Outcomes With Medtronic MiniMed Advanced Hybrid Closed-Loop Delivery: Results From a Randomized Crossover Trial Comparing Automated Insulin Delivery With Predictive Low Glucose Suspend in People With Type 1 Diabetes

Niranjala M Hewapathirana,Denis Sh Chan,Olivia J Collyns,John Shin,Benyamin Grosman,Zara L Betts,Martin I De Bock,Natalie Kurtz,Chris Frampton,Anirban Roy,Renee A Meier,Robert A Vigersky,Benjamin J Wheeler,Carla M Frewen,Shirley D Jones

doi:10.2337/figshare.13618910.v1

Abstract

Objective: To study the MiniMed™ Advanced Hybrid Closed-Loop system (AHCL) which includes an algorithm with individualised basal target set points, automated correction bolus function, and improved Auto Mode stability. Research design and Methods: This dual-centre, randomized, open-label, two-sequence cross-over study in automated insulin delivery naïve participants with type 1 diabetes (aged 7-80yrs), compared AHCL to Sensor Augmented Pump therapy with Predictive Low Glucose Management (SAP+PLGM). Each study phase was 4 weeks, preceded by a 2-4 week run-in, and separated by 2-week washout. <a>Results: 59/60 people completed the study (mean age 23.3±14.4yrs). Time in target range (TIR) 3.9-10mmol/L (70-180 mg/dL) favoured AHCL over SAP+PLGM (</a>70.4±8.1 vs 57.9±11.7) by 12.5±8.5% (p<0.001), with greater improvement overnight (18.8±12.9%, p<0.001). All age groups (children (7 – 13 years), adolescents (14 – 21 years), and adults (>22 years) demonstrated improvement, with adolescents showing the largest improvement (14.4±8.4%). Mean sensor glucose (SG) at run in was 9.3±0.9 mmol/L (167±16.2mg/dL) and improved with AHCL (8.5±0.7mmol/L (153±12.6mg/dL) (p < 0.001)), but deteriorated during PLGM (9.5±1.1mmol/L (17±19.8mg/dL), (p<0.001)).. TIR was optimal when the algorithm set point was 5.6 mmol/L (100 mg/dL) compared to 6.7 mmol/L (120 mg/dL), 72.0±7.9% vs 64.6±6.9% respectively with no additional hypoglycemia. Auto Mode was active 96.4±4.0% of the time. <a>The percentage of hypoglycemia at baseline (<3.9mmol/L (70mg/dl) and </a> £ 3.0mmol/L(54mg/dl)) was 3.1±2.1% and 0.5±0.6% respectively. During AHCL percentage time <3.9mmol/L (70mg/dl) improved to 2.1±1.4% (p=0.034) (70mg/dl), and was statistically but not clinically reduced for £ 3.0mmol/L(54mg/dl) (0.5±0.5%, p = 0.025) There was one episode of mild diabetic ketoacidosis attributed to an infusion set failure in combination with an intercurrent illness, which occurred during the SAP+PLGM arm. Conclusions AHCL with automated correction bolus demonstrated significant improvement in glucose control compared to SAP+PLGM. A lower algorithm sensor glucose set point during AHCL resulted in greater TIR, with no increase in hypoglycemia.

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