Clara Viñals, Spain
Hospital Clínic de Barcelona Endocrinology and NutritionPresenter of 1 Presentation
AUTOMATIC CONTROL OF BLOOD GLUCOSE UNDER ANNOUNCED AND UNANNOUNCED EXERCISE USING A NEW MULTIVARIABLE CLOSED LOOP CONTROLLER WITH AUTOMATIC CARBOHYDRATE SUGGESTION AND MITIGATION MODULE
Abstract
Background and Aims
Safe glycaemic control during and after exercise is a challenge in type 1 diabetes(T1D). We aimed to analyse the performance of a new Closed-Loop(CL) controller under announced and unannounced exercise.
Methods
Adults with T1D and HbA1c between 6.0-8.5% were eligible. Every subject performed three supervised inpatient studies randomized order and different days. CL included announced and unannounced exercise while Open-Loop(OL) included announced exercise only. Three sets of 15 minutes of cicloergometer at 70% of VO2max with 5 minutes of rest between them were performed. CL is based on a glucose controller built in Android platform. The controller receives glucose measurements every 5 minutes from a Continuous Glucose Monitor(CGM) and calculates insulin delivery by automatically changing, at every time interval, basal rate and making fast-acting carbohydrate(CH) intake suggestions in case of impending hypoglycaemia. During announced CL operation the controller includes a mitigation module, triggering feed-forward actions for hypoglycaemia prevention. Primary endpoint was the number of hypoglycaemic episodes during and after exercise. Secondary outcomes included Time-in-Range(TIR), CH ingestion and insulin infusion.
Results
Ten patients with T1D were included: 7 men; 40.4±7.0 years-old; 23.8±13.2 years of disease duration and HbA1c 7.3±0.8%. Announced and unannounced CL were associated with half of hypoglycaemic episodes compared to OL, with less time hypoglycaemia and lower CH consumption. Outcome details are shown in Table 1.
Conclusions
CL controller outperforms OL therapy for both, announced and unannounced exercise, in terms of number of hypoglycaemic episodes and TIR. CL is able to perform better glucose control with less supplemental CH compared to OL.