Effects of Bariatric Surgery on Different Compositions of Trunk Fat and Mechanisms

Study Overview
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Brief Summary
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This is a prospective, single-center, observational study to explore effects of bariatric surgery on different compositions of trunk fat and mechanisms.

Detailed Description
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This is a prospective, single-center, observational study to explore effects of bariatric surgery on different compositions of trunk fat and mechanisms. The primary outcome is effects of bariatric surgery on different compositions of trunk fat evaluated with MRI for patients pending bariatric surgery before and 3 months after surgery. The secondary outcome is the associations of trunk fat reduction with improvement in metabolism indicators. Before patients are enrolled in this observational study, the researchers will do a detailed screening of the subjects based on the inclusion criteria and the exclusion criteria to determine if the patients are appropriate for the study. Patients who meet the conditions of the study will be required to sign an informed consent form.

Official Title
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Effects of Bariatric Surgery on Different Compositions of Trunk Fat and Mechanisms

Conditions
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Bariatric Surgery Candidate, Adiposity, Fat Redistribution

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: BMI of >27.5 kg/m2 with T2DM; BMI of >32.5 kg/m2 with or without metabolic syndrome; Age 18-65 years old; T2DM duration < 15 years. Exclusion Criteria: Previous history of pancreatitis or pancreatic surgery; Serious T2DM complications or organic diseases; Alcohol addiction; Uncontrolled mental illness.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 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 |
| --- | --- |
| Patients pending bariatric surgery<br>A continuous cohort of patients pending bariatric surgery | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change from Baseline Subcutaneous Fat Area at 3 months after bariatric surgery | Change from baseline subcutaneous fat area (unite in cm3) evaluated with MRI at 3 months after bariatric surgery. | Baseline and 3 months after sugery | 
| Change from Baseline Visceral Fat Area at 3 months after bariatric surgery | Change from baseline visceral fat area (unite in cm3) evaluated with MRI at 3 months after bariatric surgery. | Baseline and 3 months after sugery | 
| Change from Baseline Liver Fat Percentage at 3 months after bariatric surgery | Change from baseline liver fat percentage (unite in %) evaluated with MRI at 3 months after bariatric surgery. | Baseline and 3 months after sugery | 
| Change from Baseline Pancreatic Fat Percentage at 3 months after bariatric surgery | Change from baseline pancreatic fat percentage (unite in %) evaluated with MRI at 3 months after bariatric surgery. | Baseline and 3 months after sugery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Correlation coefficient of trunk fat change with change in metabolism indicators | Correlation coefficient of trunk fat changes with changes in metabolism indicators. Trunk fat changes included changes from baseline subcutaneous fat area (unite in cm3), visceral fat area (unite in cm3), liver fat percentage (unite in %), pancreatic fat percentage (unite in %) evaluated with MRI at 3 months after bariatric surgery. Changes in metabolism indicators included changes from baseline Fasting plasma glucose (unite in mmol/L), Glycated hemoglobin (unite in %), Fasting insulin (unite in uU/mL), Fasting C-peptide (unite in ng/mL), Homeostatic Model Assessment of Insulin Resistance, Low-Density Lipoprotein Cholesterol (unite in mmol/L), High-Density Lipoprotein Cholesterol (unite in mmol/L), Cholesterol (unite in mmol/L), Triglyceride (unite in mmol/L). We used Pearson Correlation Analysis to calculate the correlation coefficient of trunk fat changes with changes in metabolism indicators. | Baseline and 3 months after sugery |