Kids ages 2 to 5 saw significant benefits with hybrid closed-loop system

Very young children with type 1 diabetes saw glycemic benefits when using a hybrid closed-loop system, the randomized PEDAP trial showed.

Among 102 children ages 2 to 5 years, the mean percentage of time that the glucose level was within the target range increased by 12.4 percentage points with the closed-loop system — also known as an artificial pancreas — versus standard of care by week 13 of follow-up (95% CI 9.5-15.3, P<0.001), reported Marc D. Breton, PhD, of the University of Virginia Center for Diabetes Technology in Charlottesville, and colleagues.

This was equivalent to about 3 hours more per day spent in the target range of 70 to 180 mg/dL, the group noted in the New England Journal of Medicineopens in a new tab or window.

In the closed-loop group, the mean percentage of time that the glucose level was within the target range increased from 56.7±18.0% at baseline to 69.3±11.1% during follow-up, while those receiving standard-of-care — consisting of either an insulin pump or multiple daily injections of insulin plus a continuous glucose monitor — went from spending 54.9±14.7% of time in range at baseline to 55.9±12.6% at week 13.

The benefits of the closed-loop system were evident within the first day of use and were maintained consistently throughout the trial, Breton’s group pointed out.

During the daytime (6 a.m. to 9:59 p.m.), the closed-loop group spent 67% of time in target range versus 56% in the standard-care group. At night (10 p.m. to 5:59 a.m.), time spent in range was 74% and 56%, respectively. The biggest between-group difference was at 5 a.m.

Compared with standard care, closed-loop users also spent significantly less time in hyperglycemia, with a mean difference of -5.4 percentage points (95% CI -7.3 to -3.6, P<0.001), and had significantly lower mean glucose levels (mean difference -17.7 mg/dL, 95% CI -23.2 to -12.2) and HbA1c levels (-0.42%, 95% CI -0.62 to -0.22).

There were no between-group differences when it came to time spent in hypoglycemia. Two cases of severe hypoglycemia occurred in the closed-loop group and one occurred in the standard-care group. There was also one case of diabetic ketoacidosis that occurred in the closed-loop group.

Overall, 48% of the closed-loop group achieved an HbA1c under 7%, as recommended by the American Diabetes Association, compared with only 30% of the standard-care group.

In an accompanying editorialopens in a new tab or window, Daniela Bruttomesso, MD, PhD, of the University of Padua in Italy, called it “remarkable” that 81% of all training for the closed-loop system was done virtually, as were 91% of all follow-up visits.

The researchers explained that the trial took place in the U.S. during the COVID-19 pandemic, which forced the research group to pivot away from face-to-face visits.

“Successful use of the closed-loop system under these conditions is an important finding that could affect the approach to initiating and monitoring the use of the closed-loop system and expand the use of such systems, particularly in patients living in areas without an endocrinologist but with reliable internet access,” Breton and team wrote.

Bruttomesso noted that a “virtual approach has several advantages over in-person visits, including a more relaxed environment, lower travel costs, and greater ease of contact with clinicians,” but “patient preferences, possible legal issues, and accessibility to technology (the families of the patients in this trial had above-average incomes) are all important considerations in choosing the most appropriate way to communicate with patients at the initiation of a closed-loop system or during routine follow-up.”

Bruttomesso instead recommended a mix of in-person and virtual clinic meetings with these very young patients to establish this diabetes management.

The 68 kids randomly assigned to the closed-loop group were fitted with Tandem Diabetes Care’s t:slim X2 insulin pump with Control-IQ Technology system. This system enables automated basal adjustments every 5 minutes and bolus corrections delivered from an insulin pump. The insulin pump was paired with a Dexcom G6 continuous glucose monitoropens in a new tab or window that sent glucose values to the pump.

The average age of PEDAP trial participants was 4 years, and baseline HbA1c was 7.6%. About 75% of patients were white, and the majority had an annual household income of $100,000 or more. At baseline, most were using an insulin pump but nearly none were using a continuous glucose monitoring system.

Currently, the insulin pump is FDA clearedopens in a new tab or window for adults and children ages 6 and up.

This isn’t the first hybrid closed-loop system to demonstrate success in this very young age group. Medtronic’s MiniMed 770G systemopens in a new tab or window was the first to be approved by the FDA for kids ages 2 to 6 years with type 1 diabetes, back in September 2020.

And in another similar trial, the KidsAP studyopens in a new tab or window published in the New England Journal of Medicine in early 2022, kids ages 1 to 7 spent a significantly longer time in target range with a closed-loop system. Here, kids were fitted with the Dana Diabecare RS insulin pump, the Dexcom G6 transmitter, and the CamAPS FX novel phone application, which ran an algorithm to predict glycemic control.