Outpatient Reduction of Nocturnal Hypoglycemia by Using Predictive Algorithms and Pump Suspension in Children

Study Summary

The purpose of this study is to see whether low blood sugar at night can be reduced by using a system that turns off the insulin pump automatically. The study system includes a continuous glucose monitor (CGM) and an insulin pump. The CGM and pump work with a regular laptop computer. A The system works by (1) measuring the glucose levels under the skin with the CGM, (2) using a computer program on the laptop to predict whether a low blood sugar is likely to occur, and (3) turning off the insulin pump when the computer program predicts that a low blood sugar will occur. We have tested the system in the home environment in individuals with type 1 diabetes age 15 years and older. We have found an indication that the system can decrease the frequency of hypoglycemia. We have not had any serious cases of high blood sugars or other problems. We are now ready to further test the system in the home environment in a younger age group to learn more about its ability to reduce overnight low blood sugar risk. This study has several phases and will take about 3 months for a patient to complete. * First, the patient will use the CGM and pump at home for up to 15 days with the help of a parent/guardian. This is done to determine if the patient meets our study criteria to proceed with the next phase of the study. * If the patient is eligible to continue in the study, the patient will need to use the full study system for at least 5 nights at home with the help of a parent/guardian. This is done to make sure the patient and parent/guardian are able to use the system correctly. The patient may participate in starting and stopping the system at home, but the parent/guardian is responsible for making sure it is used as instructed. * After that, the patient will be asked to use the study system each night for an additional 6 to 8 weeks. The parent/guardian will remain responsible for making sure the system is used as instructed. The study will include about 90 individuals with type

Primary Outcome

Each night is categorized as to whether hypoglycemia occurred. Hypoglycemia is defined as the occurrence of one or more CGM glucose values ≤70 mg/dL (3.9 mmol/L). The time period for outcome assessment each night will be from the time the system is activated in the evening until the time it is deactivated in the morning. The percentage of hypoglycemic nights (CGM glucose value ≤70 mg/dL (3.9 mmol/L)) will be tabulated separately with versus without the closed-loop control system in use. We consi

Interventions

• DEVICE Pump suspension algorithm