Long-term Adverse Effects After Bariatric Surgery on Bone Density

Study Overview
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Brief Summary
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The goal of this trial is to examine long-term effects of laparoscopic gastric bypass (LRYGB) and sleeve gastrectomy (LSG) on bone mineral density, fracture risk, and body composition ≥ 5 years post-surgery.

Detailed Description
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Bariatric surgery shows impressive results in terms of weight loss and resolution of comorbidities. Still, there are questions as to the frequency of long-term adverse effects: data on alterations in bone health are missing, The goal of this trial is to examine long-term effects of laparoscopic gastric bypass (LRYGB) and sleeve gastrectomy (LSG) on bone mineral density, fracture risk, and body composition ≥ 5 years post-surgery.

Official Title
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Long-term Adverse Effects After Laparoscopic Sleeve Gastrectomy and Roux en Y Gastric Bypass (Part A)

Conditions
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Morbid Obesity

Intervention / Treatment
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* Diagnostic Test: DEXA (= Dual-energy x-ray absorptiometry)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients who received laparoscopic sleeve gastrectomy (LSG) or laparoscopic gastric bypass (LRYGB) ≥ 5 years ago as a primary bariatric procedure will be eligible for this study. Exclusion Criteria: LSG or LRYGB as a secondary bariatric procedure (e.g. after gastric banding), patients receiving secondary bariatric operation after LSG resp LRYGB (e.g. biliopancreatic diversion), pregnancy (due to radiation exposition)
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: Diagnostic
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Gastric Bypass<br>Patients ≥ 5 years after laparoscopic gastric bypass receive DEXA (= Dual-energy x-ray absorptiometry) in order to measure bone mass density | Diagnostic Test: DEXA (= Dual-energy x-ray absorptiometry)<br>* measurement of vertebral bone and hip bone mineral density<br>|
| Active Comparator: Sleeve gastrectomy<br>Patients ≥ 5 years after laparoscopic sleeve gastrectomy receive DEXA (= Dual-energy x-ray absorptiometry) in order to measure bone mass density | Diagnostic Test: DEXA (= Dual-energy x-ray absorptiometry)<br>* measurement of vertebral bone and hip bone mineral density<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Total hip T-Score measured with dual-energy x-ray absorptiometry | measured score will be compared to reference score for this age | 5-7 years after bariatric surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Total vertebral T-Score measured with dual-energy x-ray absorptiometry | measured score will be compared to reference score for this age | 5-7 years after bariatric surgery | 
| fracture risk assessed by FRAX score | measured score will be compared to reference score for this age | 5-7 years after bariatric surgery | 
| plasma concentration of C-terminal telopeptide (CTX) | measured plasma concentration will be compared to reference for this age | 5-7 years after bariatric surgery | 
| plasma concentration of vitamin D3 | measured plasma concentration will be compared to reference for this age | 5-7 years after bariatric surgery |