Dr Mary Abraham

A world-first clinical trial has shown young people with type 1 diabetes have better glycaemic control and quality of life while on hybrid closed loop (HCL) systems versus conventional treatments, Australian endocrinologists say.

The randomised trial compared HCL’s six-month glycaemic and psychosocial efficacy with continuous subcutaneous insulin infusion and multiple daily insulin injections with or without continuous glucose monitoring in 135 T1D patients aged 12–25.

It showed those on HCL had less glycaemic variability (coefficient in variation difference: -5.7%), more time in the target glucose range of 3.9-10 mmol/L (difference: 6.7%) and less time in the hypoglycaemic range (<3.9 mmol/L, difference: -1.9%), the authors wrote in JAMA Pediatrics.

They also had better quality of life (difference: 4.4 points), with no change in diabetes distress and no serious adverse events. Neither group had severe hypoglycaemia or diabetic ketoacidosis.

While previous studies have shown six-month glycaemic benefits in adults on HCL versus standard therapy, this was the first randomised clinical trial (RCT) to explore the device’s impact in children and adolescents, said the study investigators from the Australian Juvenile Diabetes Research Fund Closed-Loop Research group.

HCL users’ time in range (TIR) improved across night and day, as did their hypoglycaemia and glycaemic variability, though there was no reduction in hyperglycaemia.

Clinical continuous glucose monitoring targets (TIR > 70%), as recommended by international consensus statement, were not uniformly reached in this trial, but most improved on HCL, the authors noted.

The device further improved quality-of-life and treatment satisfaction scores, likely due to “the reduced worry, increased confidence and trust in the system with improved glycaemic control, and increased ownership of diabetes management that were experienced by [these] users”.

“This is a vital observation, as although there may be difficulties encountered in engaging with the system, users found it beneficial in their day-to-day management,” wrote the authors led by Dr Mary Abraham, a paediatric endocrinologist at the Telethon Kids Institute and the Perth Children’s Hospital.

Such difficulties included sensor-related skin reactions and frustrations associated with the workload needed to maintain closed-loop mode, operate the machine and deal with alerts.

“Most youth in the trial continued to wear the sensor despite these [skin] issues for the perceived benefits of the sensor and system, but the ability to wear and tolerate a sensor can be seen as a critical step in a wider adoption of closed-loop systems,” they noted.

“Sensor-wear issues highlight the need for strategies in preserving skin integrity with long-term use of technological devices.”

Improving trust in automation and user experience could also help increase HCL uptake, the authors suggested.

“To our knowledge, this is the first RCT in youth with T1D to provide conclusive evidence that HCL improves glycemic outcomes and quality of life in youth with T1D.”

“The HCL system represents an important step in the pursuit of technological advancements toward a fully automated closed-loop system,” they concluded.