Australian clinical trial reports a range of benefits of Hybrid Closed Loop system

The ACBRD co-authored a Diabetes Care publication on the outcomes of a randomised controlled trial with Hybrid Closed Loop systems

By Dr Christel Hendrieckx

Findings of a six-month clinical trial have shown that adults with type 1 diabetes randomised to the Hybrid Closed Loop (HCL) insulin delivery system had increased time spent in the recommended glucose range – so-called time-in-range (TIR) – from 55% at baseline to 70%. Participants in the control group, i.e. those who continued with their usual diabetes management, experienced no improvement in TIR. In addition, HCL users reported greater sense of satisfaction in managing their diabetes.

HCL insulin delivery systems are an advanced form of diabetes management. An insulin pump and a continuous glucose monitor are connected and regulate the glucose levels based on insulin needs. This means that there is less interaction required from the person with diabetes, which can potentially reduce ‘human errors’ and the daily burden of diabetes management (Hendrieckx et al). HCL technology is also referred to as ‘artificial pancreas’, but that is not really an accurate name. The process is not yet fully automated and therefore it is called a ‘hybrid’ system. The person with diabetes still needs to enter mealtime carbohydrates, confirm the recommended bolus, and calibrate the sensor that monitors the glucose levels.

The trial was led by Prof David O’Neal (University of Melbourne) and was a collaboration with seven Australian diabetes specialist clinics and the ACBRD. Half of the 120 participants were randomised to the intervention (HCL) and used the Medtronic 670G system over a period of 6 months. The other half continued with their usual routine (either multiple daily insulin injections or an insulin pump).

The ACBRD has collaborated with the trial team in assessing participants’ experiences in using this advanced technology and how it may impact on their psychological functioning. All 120 participants completed online surveys. In this first analysis, we found, that compared to those in the control group, the HCL users reported better diabetes-specific positive well-being (ie the sense of satisfaction from managing diabetes) and diabetes-specific quality of life. There were no differences between the groups in terms of diabetes distress or satisfaction with diabetes treatment, sleep quality or cognitive functioning.

Taking part in such a large clinical trial, involves a lot of extra examinations, clinic visits and contacts with the trial team, carrying around several monitoring devices. So, the experiences of participants in such a trial could be very different from those using the HCL in real life. The Medtronic 670G is now available in Australia. The users’ perspectives can now be studied in real life.

McAuley SA, Lee MH, Paldus B, Vogrin S, I de Bock M, Abraham MB, Bach LA, Burt MG, Cohen ND, Colman PG, Davis EA, Hendrieckx C, Holmes-Walker DJ, Kaye J, Keech AC, Kumareswaran K, MacIsaac RJ, McCallum RW, Sims CM, Speight J, Stranks SN, Sundararajan V, Trawley S, Ward GM, Jenkins AJ, Jones TW, O’Neal DN for the Australian JDRF Closed-Loop Research Group. Six Months of Hybrid Closed-Loop Versus Manual Insulin Delivery With Fingerprick Blood Glucose Monitoring in Adults With Type 1 Diabetes: A Randomized, Controlled Trial. Diabetes Care, 2020; 43(12):3024-3033.

Photo by Amanda Griswold via Medtronic Diabetes.