Bone Health and Microbiome in Persons With Type 1 Diabetes

Study Overview
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Brief Summary
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It is well-established that persons with type 1 diabetes (T1D) are at an increased risk for morbidity and mortality related to bone fracture due to poor bone health, however we do not fully understand the mechanism behind the increased fracture risk. We are examining bone health and the microbiome in adolescents and young adults with type 1 diabetes to better understand the reasons behind this increased risk.

Detailed Description
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This pilot study aims to look at measures of bone health, the gut microbiome and measures of glycemia/glycemic variability in those with preclinical and clinical diabetes. Our primary and secondary outcomes are to characterize these variables, with our long term objectives to better understand the natural history of bone health in T1D, help characterize the etiology of worse bone health in those with T1D, and try to identify potential time periods for intervention.

Official Title
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Bone Health and Gut Microbiome in Persons With Preclinical and Clinical Type 1 Diabetes

Conditions
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Type1diabetes

Intervention / Treatment
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* Other: No intervention


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: - Willing and able to comply with study protocol For participants with type 1 diabetes (T1D): - T1D diagnosed clinically by an endocrinologist as documented in medical records. Exclusion Criteria: use of oral or parenteral antibiotics within 3 months use of probiotics/prebiotics/synbiotics within 3 months of enrollment; persons who eat yogurt will be asked to stop for 30 days prior to stool collection use of medications that will affect bone, including glucocorticoids, bisphosphonates chronic medications (other than insulin for those with T1D or a stable dose of thyroid hormone) uncontrolled chronic gastrointestinal disease including celiac disease (persons with T1D will be screened for celiac disease with a Tissue Transglutaminase Antibody (tTG)/Immunoglobulin A (IgA) if not done in prior 2 years) known genetic syndrome that predisposes the participant to fracture (such as osteogenesis imperfect) or skeletal dysplasia that would affect skeletal assessment (such as hypochondroplasia) pregnancy Any other condition that in the opinion of the investigator would jeopardize the safety or rights of the subject participating in the study or would make it unlikely the subject could complete the study Additional Exclusion Criteria for Healthy Controls: Presence of any diabetes autoantibody Presence of any type of diabetes or hyperglycemia (HbA1c≥5.7%)

Ages Eligible for Study
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Minimum Age: 12 Years
Maximum Age: 20 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Preclinical Type 1 Diabetes<br>Adolescents and young adults with preclinical diabetes (having at least 2 positive diabetes autoantibodies but who do not meet criteria for clinical diagnosis of type 1 diabetes). There is no intervention. Each group will complete a bone health assessment, a microbiome assessment and a glycemic assessment with the goal of better understanding the association between these different variables and bone health. | Other: No intervention<br>* No intervention<br>|
| New Onset Type 1 Diabetes<br>Adolescents and young adults with a diagnosis of clinical type 1 diabetes. There is no intervention. Each group will complete a bone health assessment, a microbiome assessment and a glycemic assessment with the goal of better understanding the association between these different variables and bone health. | Other: No intervention<br>* No intervention<br>|
| Long standing Type 1 Diabetes<br>Adolescents and young adults with type 1 diabetes for at least 2 years. There is no intervention. Each group will complete a bone health assessment, a microbiome assessment and a glycemic assessment with the goal of better understanding the association between these different variables and bone health. | Other: No intervention<br>* No intervention<br>|
| Control<br>Adolescents and young adults without any evidence of diabetes or hyperglycemia. There is no intervention. Each group will complete a bone health assessment, a microbiome assessment and a glycemic assessment with the goal of better understanding the association between these different variables and bone health. | Other: No intervention<br>* No intervention<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| High-resolution peripheral quantitative computed tomography (HRpQCT) strength of cortical and trabecular bone. | Our primary outcome is HRpQCT strength of cortical and trabecular bone. | Through study completion, which is within 12 weeks of visit 1 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Dual-energy x-ray absorptiometry (DXA) | Lumbar spine, hip, and total body less head by DXA | Through study completion, which is within 12 weeks of visit 1 | 
| Microbiome | Gut microbiome profile | Through study completion, which is within 12 weeks of visit 1 | 
| Glycemia | Serum Hemoglobin A1C (HbA1c) and Time in Range using a continuous glucose monitor (CGM) | Through study completion, which is within 12 weeks of visit 1 |