Key points:
- Management of type 1 diabetes is hard work in very young children, due to their unpredictable eating and activity patterns.
- We wanted to see if a closed-loop system that automatically adjusts insulin delivery based on real-time glucose levels could improve glucose control in very young children with type 1 diabetes.
- In the KidsAP02 study, children used a standard insulin pump and sensor for 4 months, and a closed-loop system for 4 months.
- With hybrid closed-loop therapy, young children spent an extra 2.1 hours with glucose levels in the recommended target range every day, without having more hypos.
- We recommend that closed-loop therapy should be first line treatment for very young children with type 1 diabetes.
Why was the research needed?
In type 1 diabetes (T1D) the body’s own immune system destroys cells in the pancreas that make insulin, leading to high glucose levels. People with T1D need to inject insulin several times a day and regularly check blood glucose levels. Keeping glucose levels stable and in the healthy range is challenging, especially in very young children, because their eating habits and activity levels are unpredictable. Many children use an insulin pump and glucose sensor to help manage their T1D, but having to check glucose levels and deciding how much insulin to give is stressful and time-consuming for parents and caregivers, and can affect the whole family’s quality of life.
A closed-loop system is a new technology, which tries to mimic what the healthy pancreas does. The closed-loop system is made up of three components:
- A glucose sensor, which is worn on the skin and measures glucose levels automatically every few minutes.
- The glucose levels are sent in real-time to a computer algorithm in a smartphone App, which automatically calculates how much insulin the person needs to keep their glucose levels in the normal range.
- The algorithm then automatically tells the insulin pump how much insulin to deliver.
Currently all closed-loop systems are ‘hybrid’ systems. This means parents need to give insulin every time the child eats. The rest of the time the closed-loop system automatically gives insulin to keep glucose levels in the normal range. Parents are able to see their child’s glucose and insulin information on a mobile app, even when the child is not with them.
What did we do?
In the KidsAP02 study we wanted to see if using a closed-loop system for children aged 1 to 7 years could help improve their glucose levels. 74 children in four countries (Austria,
Germany, Luxembourg and the UK) spent four months having their glucose levels managed using only an insulin pump and glucose sensor, and four months using the CamAPS FX closed-loop system. Observing both methods in all children allowed us to compare to what extent using a closed-loop system could achieve better glucose levels than the ‘usual’ method.
What were the results of our study?
During the 4 months when children used the closed-loop system, their glucose levels were in the target range an extra 2.1 hours per day, compared to when they used only insulin pump and glucose sensor. They spent 72% of their day with glucose levels in the target range (3.9 to 10.0mmol/L) using closed-loop, compared to 63% using pump and sensor. At the end of each 4-month period, all children had their HbA1c measured, which looks at overall blood glucose control over the previous 3 months. After children used the closed-loop system, their HbA1c was 4mmol/mol lower than when they used pump and sensor. We know that a lower HbA1c reduces the risk of long-term diabetes complications like kidney, heart and eye disease.
High glucose levels can affect brain growth and learning in young children with T1D. In the study, children spent 32% of their day with high glucose levels when using pump and sensor, but this was reduced to 23% when using closed-loop. Low glucose levels can be dangerous too, but children spent no extra time with low glucose levels when they used closed-loop.
When children used the closed-loop system, their glucose levels were most stable overnight, with more than 80% of glucose levels in the target range. Parents of children with T1D often sleep poorly because they have to get up to check glucose levels or give insulin. Using closed-loop kept glucose levels more stable at night, which could help to improve parents’ sleep.
How do these results help other young children living with T1D?
Our study shows that the Cambridge closed-loop system significantly improves glucose levels in very young children with T1D, without children having any extra low glucose episodes (‘hypos’). We therefore recommend that all very young children with T1D should be given the opportunity to use a closed-loop system.
What happens next?
Together with Digibete, an NHS-funded video platform, we are creating videos that show the results of the KidsAP02 study. These videos will be shared with families, healthcare professionals and the public to help spread the message about closed-loop and its benefits for very young children.
This year, the National Institute for Clinical Excellence (NICE), is publishing new guidelines on closed-loop and they will make recommendations on whether it should be available on the NHS. We have shared the study results with NICE and hope that the new guidelines will make closed-loop more accessible for children and their families.
Main research article: https://www.nejm.org/doi/full/10.1056/NEJMoa2111673?query=featured_endocrinology
Press release: https://www.cam.ac.uk/stories/KidsArtificialPancreas
This work was funded by the European Commission within the Horizon 2020 Framework Programme under the grant agreement number 731560. Additional support for the artificial pancreas work from National Institute for Health Research Cambridge Biomedical Research Centre, and JDRF. The views expressed are those of the author(s) and not necessarily those of the funders.
