Closed-Loop Insulin Delivery in Children Less Than 7 Years of Age

The investigators are conducting this study to find out whether a new device can control blood sugar levels in children who have Type 1 diabetes. In Type 1 diabetes, children have high blood sugar levels because they do not make enough insulin. The standard treatment is to give insulin either by shots or using an insulin pump. A new device, called closed-loop insulin therapy, uses a continuous glucose monitor (CGMs) linked to an insulin pump by a computer. The CGM will send the sugar levels to a computer which automatically figures out how much insulin to give and then gives that amount of insulin through the insulin pump. It will give the child insulin to bring sugar levels down if they are high, and will give less insulin if the child's blood sugar is getting lower. Earlier research using closed-loop insulin therapy has shown the ability for it to improve diabetes care in adults and older children, but there has been no research of closed-loop insulin therapy in young children. This study will compare children's current insulin therapy with the closed-loop system. The knowledge that the investigators gain from this research will help us to figure out whether closed-loop therapy can work in young children, hopefully leading to better Type 1 diabetes care.

We will perform a randomized cross-over study of semi-closed-loop insulin therapy in children less than 7 years old with type 1 diabetes. Subjects will be admitted to the inpatient clinical research center for 48 hours. They will receive their standard home insulin therapy for one day and semi-closed-loop insulin therapy for the other day.

Subjects insulin doses were adjusted based on a proportional-integral-derivative algorithm using the continuous glucose monitor readings from 10 PM - noon.

Time spent within target glucose range based on the glucose meter measurements between 10 PM and 8 AM. The target range is 110-200 mg/dl as this is the American Diabetes Association defined target overnight range for this age group.

Inclusion Criteria: Age < 7 years old Type 1 Diabetes (as diagnosed by outpatient endocrinologist) with duration greater than 6 months Treated with insulin pump therapy for greater than 6 weeks Exclusion Criteria: Any other chronic medical condition Weight below 10 kg as this is the minimal required weight for the amount of blood being drawn

Dauber A, Corcia L, Safer J, Agus MS, Einis S, Steil GM. Closed-loop insulin therapy improves glycemic control in children aged <7 years: a randomized controlled trial. Diabetes Care. 2013 Feb;36(2):222-7. doi: 10.2337/dc12-1079. Epub 2012 Oct 1.