GLP1R-imaging in Post-RYGB Hypoglycemia

Study Overview
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Brief Summary
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In order to evaluate the difference in beta cell mass in patients with and without hyperinsulinemic hypoglycemia after Roux en Y gastric bypass (RYGB) investigators aim to compare quantitative PET imaging of the pancreas between these patient groups. These highly relevant data will provide investigators with more information on the possible role of beta cell mass in the mechanisms of hyperinsulinemic hypoglycemia bariatric surgery.

Official Title
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Visualizing Beta Cells in Patients With Hyperinsulinemic Hypoglycemia After Bariatric Surgery

Conditions
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Obesity, Hypoglycemia Post Gastric Bypass Surgery, Hyperinsulinemic Hypoglycemia

Intervention / Treatment
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* Diagnostic Test: GLP-1R PET


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Signed informed consent Patients: - Persisting hyperinsulinemic hypoglycemia after a low-carbohydrate diet and/or insulin suppressive medication for one year. Controls: RYGB at least 2 years ago Normal glucose levels before and after RYGB (fasting glucose between 4 and 6 mmol/l or HbA1c between 20 and 42 mmol/mol) Score ≤ 7 on Sigstad's scoring system (Table 1) Hypoglycemia excluded by 14-day continuous glucose monitoring Individual matched to HH group on age (± 5 years), sex and BMI at time of inclusion (± 2 kg/m2) Exclusion Criteria: Anti-diabetic medication in the past 6 months Treatment with synthetic Exendin (Exenatide, Byetta®) or Dipeptidyl-Peptidase IV inhibitors in the past six months. Known liver failure or serum liver values over 2 times normal value at the time of standard laboratory assessment. Normal values of total bilirubin, γ-GT, ASAT and albumin are <21 μmol, <40 U/l, <30 U/l and 35-50 g/l respectively Pregnancy or the wish to become pregnant within 6 months Breast feeding Kidney failure, i.e. calculated creatinine clearance below 40 ml/min Age < 18 years No signed informed consent

Ages Eligible for Study
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Minimum Age: 18 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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Design Details

Primary Purpose: Basic Science
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Patients<br>Patients with hypoglycemia | Diagnostic Test: GLP-1R PET<br>* Beta cell function (tests) and measure for beta cell mass (PET)<br>* Other names: Arginine stimulation test;|
| Other: Controls<br>Patients without post-bariatric hypoglycemia | Diagnostic Test: GLP-1R PET<br>* Beta cell function (tests) and measure for beta cell mass (PET)<br>* Other names: Arginine stimulation test;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Pancreatic uptake of 68Ga-NODAGA-exendin-4 |  | baseline | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Beta cell function | Measured as total insulin during MTT and insulin peak during arginine test | baseline |