Closed-loop insulin delivery: update on the state of the field and emerging technologies

Abstract

Introduction:Over the last five years, closed-loop insulin delivery systems have transitioned from research-only to real-life use. A number of systems have been commercialized and are increasingly used in clinical practice. Given the rapidity of new developments in the field, understanding the capabilities and key similarities and differences of current systems can be challenging. This review aims to provide an update on the state of the field of closed-loop insulin delivery systems, including emerging technologies. Areas covered: We summarize key clinical safety and efficacy evidence of commercial and emerging insulin-only hybrid closed-loop systems for type 1 diabetes. A literature search was conducted and clinical trials using closed-loop systems during free-living conditions were identified to report on safety and efficacy data. We comment on emerging technologies and adjuncts for closed-loop systems, as well as non-technological priorities in closed-loop insulin delivery. Expert opinion: Commercial hybrid closed-loop insulin delivery systems are efficacious, consistently improving glycemic control when compared to standard therapy. Challenges remain in widespread adoption due to clinical inertia and the lack of resources to embrace technological developments by health care professionals.

Glucose control and psychosocial outcomes with use of automated insulin delivery for 12 to 96 weeks in type 1 diabetes: a meta-analysis of randomised controlled trials

“…The risk of bias assessment of each RCT is provided in the Additional file 1 : Appendix A for clinical (Additional file 1 : Figure S3) and functional (Additional file 1 : Figure S4) outcomes. For clinical outcomes, three were rated as “some concerns'' due to missing outcome data [ 7 ] and deviations from the protocol (machine errors) [ 35 , 40 ], and seven were rated as “high risk” due to lack of laboratory-measured HbA1c assessment [ 44 , 46 ] or due to insufficient washout time [ 36 , 38 , 43 , 47 ] in crossover studies. All trials were open-label but used adequate methods for allocating participants and objective measurements of clinical outcomes.…”

“…The goal of such devices is to achieve better glycaemic control, reduce glucose variability, and decrease the risk of micro and macrovascular complications as well as treatment distress [ 6 ]. An AID system consists of three components: a continuous glucose monitor (CGM), a pump able to continuously deliver insulin, and a computer algorithm controlling insulin delivery through glucose-responsive feedback [ 7 ]. In the last 15 years, multiple closed-loop (CL) systems were developed, such as predictive low-glucose suspend (PLGS) systems, hybrid closed-loop (HCL) systems, and fully closed-loop (FCL) systems, however, their long-term impact on clinical and functional outcomes is still unclear.…”

The changing landscape of automated insulin delivery in the management of type 1 diabetes

“…PID controllers modify insulin rates by evaluating glucose excursions from three perspectives: deviation from target glucose (proportional component), area under the curve between measured and target glucose level (integral component), and rate of change of measured glucose levels (derivative component) ( 21 ). MPC algorithms predict future glycaemic excursions and adjust insulin delivery based on inputs including sensor glucose levels and insulin boluses given, simultaneously considering insulin absorption delays, active insulin, and diurnal and post-prandial variability in glucose levels ( 22 ). The fuzzy logic approach is less commonly used and involves modulating insulin delivery based on rules which reflect the reasoning of experienced diabetes practitioners.…”

Automated Insulin Delivery (AID) Systems: Use and Efficacy in Children and Adults with Type 1 Diabetes and Other Forms of Diabetes in Europe in Early 2023

“…The management of Type 1 Diabetes (T1D) has changed substantially over the past years. Since the introduction of the first insulin pump into clinical practice which allowed continuous subcutaneous insulin infusion (CSII) in the 1970s, the scientific community and T1D patients’ goal for years has been the creation of an artificial pancreatic system (APS) [ 1 , 2 , 3 ]. APS is a closed-loop system capable of automatically administering an appropriate dose of insulin based on the level of blood glucose.…”