Impact of Bariatric Surgery on Nonalcoholic Fatty Liver Disease

Study Overview
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Brief Summary
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The purpose of this study is to investigate the effect of weight loss rate on liver steatosis, steatohepatitis, fibrosis and cardiovascular risk at different stages before and after bariatric surgery. The investigators also aim to study the short-term effect of bariatric surgery on gastric cholecystokinin levels before and 10 days after the bariatric surgery.

Official Title
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The Impact of Bariatric Surgery on Nonalcoholic Fatty Liver Disease and Cardiovascular Risk Utilizing Non-invasive Measures

Conditions
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Nonalcoholic Fatty Liver Disease, Nonalcoholic Steatohepatitis

Intervention / Treatment
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* Procedure: Sleeve gastrectomy


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 20≤ age ≤80 BMI>35kg/m2 Men and women Fatty infiltration in liver ultrasonography Exclusion Criteria: Alcohol drinking > 140g/week Presence of hepatitis B or C or HIV Known liver disease such as: Wilson's disease hemochromatosis α1-antitrypsin deficiency autoimmune liver disease primary biliary cirrhosis primary sclerosing cholangitis)

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 80 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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| NAFLD after SG<br>26 patients with NAFLD undergoing sleeve gastrectomy (SG). | Procedure: Sleeve gastrectomy<br>* An intra-operative liver biopsy was performed in 20 patients<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change from baseline liver steatosis, steatohepatitis and fibrosis at different stages after bariatric surgery, measured by non-invasive measurements as described below. | Measurements to be performed to assess liver disease stage at baseline and at 8-12 days and 12, 24 and 48 weeks after surgery: Blood tests of liver functions (Alanine transaminase, Aspartate transaminase, Alkaline Phosphatase, gamma-glutamyl transpeptidase, ferritin, prothrombin-time (PT), international normalized ratio (INR), Total/Direct Bilirubin, Albumin, uric acid), lipids profile (total cholesterol, triglycerides, HDL, LDL) and diabetes biomarkers (insulin, glucose, HbA1c). Blood tests of adiponectin (only at baseline and 48 weeks after surgery). Fibroscan test for quantifying liver fibrosis by means of elastography (only at baseline and 48 weeks after surgery). A blood test (FibroMax) for determining the stage and grade of liver damage (only at baseline and at 24 and 48 weeks after surgery). OWLiver® test (a serum based test that can discriminate NAFLD from steatohepatitis using metabolomics) at baseline and 48 weeks after surgery. | Baseline is defined as three weeks to one month before surgery. Different stages to compare to baseline are as following: 8-12 days and 12, 24 and 48 weeks after surgery. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change of postoperative cardiovascular risk compared to baseline. | Patients will undergo brachial artery flow-mediated dilation (FMD) test (surrogate marker for endothelial function and cardiovascular risk). | Baseline is defined as three weeks to one month before surgery. Change will be assessed 6-12 months after surgery. | 
| Change in cholecystokinin levels before and after the surgery. | In addition, gastric cholecystokinin levels will be measured from the removed stomach tissue. | Baseline levels of cholecystokinin at 1-2 days before surgery compared to 8-12 days after surgery. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Nonalcoholic fatty liver disease, Nonalcoholic steatohepatitis, Obesity, Bariatric surgery, Weight loss