Body Mass Index and Growth Parameters Evolution in Children Treated With Hybrid Closed Loop System for Type 1 Diabetes

Study Overview
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Brief Summary
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Overweigth and obesity are commonly diagnosed in children with type 1 diabetes, and frequently an increase of wiegth and BMI is observed after diagnoses. Hybrid cloosed loop system are new system where insulin is continually adapted to glycemia (using an algorythme). The weight and growth trajectory of children treated with this system is poorly described.

Detailed Description
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Unlike type 2 diabetes, which is a frequent metabolic complication of obesity, type 1 diabetes is not a consequence of overweight or obesity, or of an excessively sweet or unbalanced diet. However, more and more studies are linking type 1 diabetes to obesity. An international study with 23 026 children suffering from type 1 diabtes has shown that 22.3% of boys and 27.2% of children have overweight, and 6.8% and 6.3% respectively obesity . Several hypothesis are made to explain this trend : a consequence of intensive insulinotherapy, the fear of hypoglycemia with unnecessary glucose intake, the increase of caloric intake and the decrease of physcial activity. Moreover, subcutaneous insulinotherapy leads to modification in body composition with a increase in fat mass . Nevertheless, some studies highlights a possible role of obesity in the type 1 diabetes development( familial history of type 2 diabetes more common in children with type 1 diabetes , inverse relation with age at diagnosis and BMI suggesting that children with higher BMI will be diagnosed early in age . Hybrid closed-loop systems, in which the insulin flow rate is adjusted almost instantaneously to the blood glucose level by using an algorithm with a CSII and a CGM, are new systems that have gradually been used in current practice . These systems are significantly associated with an improvement in glycemic control (HbA1C and TIR)[17], a reduction in the time spent in hypoglycemic states , and with an improvement in quality of life. Nevertheless, the impact of this new treatment on weight evolution has been poorly described. A previous study with 50 children included did not show a BMI modification after 1 year of treatment. Individually, some patients following in our center have shown a reduction of BMI after treatment of type 1 diabetes with with hybrid closed loop system. This leads us to perform an observational study in order to describe the trajectory of BMI and growth parameters of children suffering from type 1 diabetes (expressed in standard deviations (SDS) after 6 months, 1 year and 2 years of treatment with hybrid closed loop system in the university hospital of Nancy. The second objective is to identify potential factors associated with the positive evolution of BMI at 6 months, 1 year and 2 years.

Official Title
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Body Mass Index and Growth Parameters Evolution in Children Treated With Hybrid Closed Loop System for Type 1 Diabetes

Conditions
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Diabetes Mellitus, Type 1, Obesity, Overweight, Child Obesity

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: children between 6 and 18 years at the beginning of treatment with HCL type 1 diabetes follow up in University Hospital of Nancy between 01/01/2021 - 31/12/2023 treatement with HCL since 6 months Exclusion Criteria: parental opposition for the study pregnancy

Ages Eligible for Study
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Minimum Age: 6 Years
Maximum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Body mass index (BMI) variation after 6 months of treatment with hybrid closed loop (HCL) | variation of BMI expressed in standard deviations after 6 months with HCL | 6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Body mass index (BMI) variation after 12 months of treatment with hybrid closed loop (HCL) | variation of BMI expressed in standard deviations after 12 months with HCL | 12 months | 
| Body mass index (BMI) variation after 24 months of treatment with hybrid closed loop (HCL) | variation of BMI expressed in standard deviations after 24 months with HCL | 24 months | 
| Growth velocity variation after 6 months of treatment with hybrid closed loop (HCL) | variation of Growth velocity expressed in standard deviations after 6 months with HCL | 6 months | 
| Growth velocity variation after 12 months of treatment with hybrid closed loop (HCL) | variation of Growth velocity expressed in standard deviations after 12 months with HCL | 12 months | 
| Growth velocity variation after 24 months of treatment with hybrid closed loop (HCL) | variation of Growth velocity expressed in standard deviations after 24 months with HCL | 24 months | 
| description of metabolic parameters at 6 months | HbA1C at 6 months | 6 months | 
| description of metabolic parameters at 12 months | HbA1C at 12 months | 12 months | 
| description of metabolic parameters at 24 months | HbA1C at 24months | 24 months |