Type 1 Diabetes Mellitus
Conditions
Keywords
Type 1 diabetes mellitus, Automated insulin delivery, Continuous glucose monitoring, Carbohydrate counting, Meal announcement
Brief summary
The purpose of this study is to assess the long-term evolution of patient interaction with the CONTROL-IQ (Tandem™) hybrid closed-loop (HCL) system in individuals with type 1 diabetes over 24 months. Specifically, the study examines user-initiated boluses and carbohydrate announcements to determine whether initially low-engagement users increase their involvement over time or, conversely, whether highly engaged users gradually rely more on automation.
Detailed description
Automated insulin delivery (AID) systems have revolutionized type 1 diabetes (T1D) management, offering superior glycemic control and quality of life compared to sensor-augmented insulin pumps or multiple daily injections (MDI). However, current AID systems operate as hybrid closed-loop (HCL) systems, requiring user intervention for meal boluses, including carbohydrate counting and timely insulin administration. Control-IQ (Tandem™) was the second AID system reimbursed by the French National Health Insurance and is now widely used in France. It combines the Tandem™ t:slim insulin pump with Dexcom™ G6 continuous glucose monitoring (CGM), adjusting basal insulin every five minutes based on glucose predictions and delivering automatic correction boluses once per hour. Despite these automation features, users must still manually initiate meal boluses, and additional correction boluses remain optional. While engagement in carbohydrate counting and timely meal announcements improves metabolic outcomes, real-world data suggest that AID benefits individuals across varying engagement levels. Long-term data on patient behavior and engagement, particularly regarding carbohydrate announcements and the ratio of automatic to user-initiated boluses, remain limited. Understanding these patterns could reveal whether initially low-engagement users increase involvement over time or whether highly engaged users eventually rely more on automation. This single-center, 24-month observational study will follow all T1D patients treated with Control-IQ at the Centre Hospitalier Sud-Francilien between October 2021 and October 2024.
Interventions
DEVICECONTROL-IQ (Tandem™)
interaction with the CONTROL-IQ (Tandem™) hybrid closed-loop (HCL) system in individuals with type 1 diabetes
Sponsors
Centre Hospitalier Sud Francilien
Study design
Observational model
COHORT
Time perspective
RETROSPECTIVE
Eligibility
Sex/Gender
ALL
Healthy volunteers
No
Inclusion criteria
* Patients using the CONTROL-IQ hybrid closed-loop system with data uploaded to the myDiabby platform at least once between October 2021 and October 2024, affiliated with the diabetology department of CHSF.
Exclusion criteria
* Patients with a type of diabetes other than type 1 diabetes. * Patients who have objected to the use of their data.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| number of automatic boluses | repeated measurement over 24 months (8 quarters) | To assess the 24-month evolution of the automatic-to-user-initiated bolus ratio |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| insulin dose (UI) | repeated measurement over 24 months (8 quarters) | Measurement of the quarterly evolution, over 24 months, of the average of total daily insulin dose (UI) |
| carbohydrates | repeated measurement over 24 months (8 quarters) | Measurement of the quarterly evolution, over 24 months, of the average amount of carbohydrates reported daily in closed-loop mode (CONTROL-IQ). |
| glucose | Repeated measurement over 24 months (8 quarters) | Measurement of the quarterly evolution, over 24 months, of continuous glucose monitoring parameters, including average glucose in closed-loop mode (CONTROL-IQ). |
| time spent in closed-loop mode | repeated measurement over 24 months (8 quarters) | Measurement of the quarterly evolution, over 24 months, of the percentage of time spent in closed-loop mode (CONTROL-IQ ON) |
| glucose coefficient of variation | Repeated measurement over 24 months (8 quarters) | Measurement of the quarterly evolution, over 24 months, of continuous glucose monitoring parameters, including glucose coefficient of variation in closed-loop mode (CONTROL-IQ). |
| percentage of time in target range (70-180 mg/dL) | Repeated measurement over 24 months (8 quarters) | Measurement of the quarterly evolution, over 24 months, of continuous glucose monitoring parameters, including percentage of time in target range (70-180 mg/dL) in closed-loop mode (CONTROL-IQ). |
| glucose management indicator | Repeated measurement over 24 months (8 quarters) | Measurement of the quarterly evolution, over 24 months, of continuous glucose monitoring parameters, including average glucose management indicator in closed-loop mode (CONTROL-IQ). |
Countries
France
Outcome results
None listed