Clinical and Metabolic Characterization of Long-term Courses of Obesity Patients

Study Overview
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Brief Summary
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The long-term courses after bariatric surgery are not sufficiently known. Furthermore there is a heterogeneity in postoperative responses. The aim of this study is to investigate the glycemic course (prediabetes, development of diabetes) of patients with obesity (BMI>=35 kg/m2) who had undergone bariatric surgery compared to patients with obesity who have not. A further aim is to investigate predictors of weight development, development of body composition and insulin sensitivity of patients who had undergone bariatric surgery compared to obesity patients who have not undergone bariatric surgery. The long-term courses after different surgical procedures (Roux-Y vs Sleeve) will be compared. In this study 300 patients with obesity who had been metabolically characterized in a previous study will be recruited. These patients are examined (medical history, physical examination including ECG, BIA, weight, height) and metabolically characterized. Participants without diabetes undergo a glucose tolerance test and fasting blood sampling will be performed in participants with diabetes. All patients complete questionnaires to activity, nutrition, life quality, impulsiveness, depression and eating behavior. Randomly selected participants will be offered an abdominal fat tissue biopsy. When consent is given, this will be performed at least two days after the glucose tolerance test.

Official Title
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Klinische Und Metabolische Charakterisierung Der Langzeitverläufe Von Adipositas-Patienten Mit Vergleich Von Bariatrisch Operierten zu Nicht Operierten Patienten

Conditions
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Obesity

Intervention / Treatment
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* Procedure: Bariatric surgery


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Participation in the study  Das ADIP-Programm: Charakterisierung adipöser Probanden mittels genauer phänotypischer und genotypischer Klassifizierung Exclusion Criteria: BMI < 35 kg/m2 at start of the previous study Women during pregnancy and lactation Patients who are unable to give their consent Patients who have undergone surgery within the last 3 months acute disease or infection within the last 4 months HIV- or hepatitis B/C-positive for biopsy of fat tissue: known coagulation disorder or PTT or INR out of reference range

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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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Obese patients who have received a bariatric surgery<br>Obese patients who have undergone a bariaric surgery as part of routine clinical management within the indication of this intervention. | Procedure: Bariatric surgery<br>* Obese patients who haveundergone bariatric surgery as part of routine clinical management within the indication of this intervention.<br>|
| No Intervention: Obese patients without a bariatric surgery<br>Obese patients who have not undergone bariaric surgery. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of diabetes | Diabetes mellitus as determined by HbA1c, fasting glucose and/or post-challenge glucose (120 min after an 75g oral glucose tolerance test). | On average 11 years after baseline assessment (previous study). | 
| Incidence of prediabetes | Prediabetes as determined by fasting glucose and/or post-challenge glucose (120 min after an 75g oral glucose tolerance test). | On average 11 years after baseline assessment (previous study). | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in body weight | Effect of bariatric surgery versus no surgery on body weight assessed by calculating BMI. | Baseline (previous study) and after an average of 11 year (follow-up visit) | 
| Change in body fat mass | Effect of bariatric surgery versus no surgery on body fat mass assessed by bioelectric impedance analysis. | Baseline (previous study) and after an average of 11 year (follow-up visit) | 
| Change in fat free mass | Effect of bariatric surgery versus no surgery on fat free (kg) mass assessed by bioelectric impedance analysis. | Baseline (previous study) and after an average of 11 year (follow-up visit) | 
| Change in insulin sensitivity | Effect of bariatric surgery versus no surgery on insulin sensitivity assessed by 75g oral glucose tolerance test. | Baseline (previous study) and after an average of 11 year (follow-up visit) | 
| Occurence of diabetic complications - nephropathy | Occurence of diabetes complications: nephropathy measured as urine microalbuminuria. | On average 11 years after baseline assessment (previous study). | 
| Occurence of diabetic complications - retinopathy | Occurence of diabetes complications: retinopathy assessed by retinal examination | On average 11 years after baseline assessment (previous study). | 
| Occurence of diabetic complications - neuropathy | Occurence of diabetes complications: neuropathy assessed by Michigan-neuropathy screening tool | On average 11 years after baseline assessment (previous study). | 
| Occurence of macrovascular complications | Occurence of manifestations of coronary artery disease (myocardial infarction, angina pectoris) or stroke or peripheral artery disease. | On average 11 years after baseline assessment (previous study). |