Identification of Biomarkers of Response After Bariatric Surgery in Morbidly Obese Patients

Study Overview
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Brief Summary
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The prevalence of obesity in Spain is about 21.6%. The discouraging results provided by dietary treatment, together with the lack of funding for pharmacological treatment, have led to the progressive use of bariatric surgery (CB). Besides weight loss, CB associates a beneficial effect on metabolic comorbidities. However, 25-30% of operated patients present a weight response considered inappropriate, they do not resolve their comorbidities and/or present a weight-regain shortly after surgery. Therefore, predictive strategies are necessary to allow a correct selection of obese patients who are candidates for CB. The main hypothesis of the study is that various factors such as psychopathological profile, body composition and metabolic alterations related to morbid obesity can influence the response to bariatric surgery.

Detailed Description
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The investigators have designed a prospective study in which 200 consecutive patients from the outpatient clinic of the Morbidly Obesity Unit of the Vall d'Hebron Hospital will be included, meeting criteria for bariatric surgery (with BMI> 40 kg / m2 or BMI> 35 kg /m2 in the presence of comorbidities) and will undergo surgery in the investigator's center between September 2018 and September 2019. All patients will undergo (baseline, month, 6, 12 and 24 month): complete clinical history, analysis complete biochemistry, 2 blood samples will be extracted to study metabolomics, stool sample for microbiota study, bioimpedance for the study of body composition, determination of AGEs in the skin and lens, cognitive function assessment, retinal function assessment by microperimetry and they will be asked to complete several specific questionnaires for the evaluation of the psychopathological profile and the dietetic survey.

Official Title
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Identification of Biomarkers of Response After Bariatric Surgery in Morbidly Obese Patients

Conditions
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Morbid Obesity

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients fulfilling criteria for bariatric surgery (BS). Signed informed consent fir the BS and the study. Previous accomplishment of the preoperative protocol for the BS at our site. undergo BS between September 2018 and December 2019 Able to read and understand the specific questionnaires. Exclusion Criteria: Any contraindication for the bariatric surgery. Impossibility to follow-up at our site (eg: patients from outside out community).

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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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Bariatric surgery<br>200 consecutive patients that will undergo bariatric surgery as a routinary procedure at our site | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Evolution of the body mass index in morbidly obesity patients after bariatric surgery (BS). | For the assessment of the evolution after bariatric surgery the investigators will use the body mass index parameter (BMI), calculated with the following formula: Body mass index (BMI) will be calculated as weight (kg)/height (m2). Changes in BMI, will be evaluated at 1, 6, 12 and 24 month after bariatric surgery. | 24month | 
| Evolution of the excess of weight loss % (EWL%) after bariatric surgery. | - Excess of weight loss % (EWL%) will be calculated using the following formula: pre-bariatric surgery weight (kg)-visit weight (kg)/pre-bariatric surgery weight (kg)- ideal weight (for BMI 25) (kg) x 100%. Changes in EWL% will be evaluated at 1, 6, 12 and 24 month after bariatric surgery. | 24 month | 
| Evolution of the total weight loss after bariatric surgery | -Total weight loss (TWL) will be calculated as: pre-bariatric surgery weight (kg)- visit weight (kg). Changes in TWL will be evaluated at 1, 6, 12 and 24 month after bariatric surgery. | 24 month | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Evaluation of the body composition scores before and after bariatric surgery by means of bioimpedanciometry. | All the patients will undergo before and after bariatric surgery (after 1,6, 12, and 24 month) the bioimpedance Bodystat QuadScan 4000 evaluation. The results are expressed in kg of free fatty mass and fatty mass. The change in Kg of the free fatty mass and fatty mass regarding the baseline will be evaluated. | 24 month | 
| Evaluation of the Advanced Glycation End products (AGEs) before and after bariatric surgery. | All the patients will undergo AGEs evaluation before, at 6, 12, 24 months after bariatric surgery (eye and skin using CLEARPATH DS-120 and microCAYA-AGEreader respectively). The presence of the AGEs is automatically calculated as standard deviation from the normal values for age and gender. The differences between the baseline value, at 6,12 and 24 month will be evaluated. | 24 month | 
| Evaluation of neuropsychological scores before and after bariatric surgery: eating attitudes | Eating Attitudes Test (EAT) evaluates the possible eating disorders of the patients. The test will be used before, at 6, 12, and 24month after bariatric surgery and the scores will be compared. The investigators will search for correlations with the BMI, EWL% and TWL changes. The subjects will have to answer 40 items, each of it measured from 0 to 3, total score may range between 0 and 120. The accepted cut-off for diagnosis eating disorders is more than 20 for spanish population. | 24month | 
| Evaluation of neuropsychological scores before and after bariatric surgery: Attention-Deficit Hyperactivity Disorder (ADHD) | ADHD rating scale will be used before, at 6, 12, and 24month after bariatric surgery and the scores will be compared. The investigators will evaluate the existence of correlations with the BMI, EWL% and TWL changes. The scale ranges between 0-27 points, the highest the value, the higher de attention deficit and hyperactivity. | 24month | 
| Evaluation of neuropsychological scores before and after bariatric surgery: Sheehan Disability Inventory (SDI). | Sheehan Disability Inventory (SDI) scale will be used before, at 6, 12, and 24month after bariatric surgery and the scores will be compared. The investigators will evaluate the existence of correlations with the BMI, EWL% and TWL changes. The Sheehan Disability Inventory evaluates the social fobia and the score ranges between 0-30. A score > 15 is considered pathological. | 24 month | 
| Evaluation of neuropsychological scores before and after bariatric surgery: Zuckerman-Kuhlman Personality Questionnaire (ZKPQ). | ZKPQ personality evaluation will be used before, at 6, 12, and 24month after bariatric surgery and the scores will be compared. The investigators will evaluate the existence of correlations with the BMI, EWL% and TWL changes. ZKPQ is a quantitative scale which evaluates 6 personality dimensions: aggressivity (19 points), anxiety (19 points), impulsivity (17 points), activity (17 points), sociability (17 points). There is no clear cut-off for this test. In consequence, there will be evaluated only the changes after the bariatric surgery, compared with the baseline score. The higher the score the higher the personality disorder. | 24month | 
| Evaluation of neuropsychological scores before and after bariatric surgery: COPE- stress management strategies. | COPE test will be used before, at 6, 12, and 24month after bariatric surgery and the scores will be compared. The investigators will evaluate the existence of correlations with the BMI, EWL% and TWL changes. COPE is a quantitative scale which evaluates 15 strategies of stress coping. The total score ranges between 15-60 points. There is a direct relation between the score and the ability to manage the stress, but no clear cut-off for this test exists. In consequence, we will only evaluate the changes after the bariatric surgery regarding the baseline score. The highest score indicates better strategies to cope the stress. | 24month | 
| Evaluation of neuropsychological scores before and after bariatric surgery: ROTTER´s locus of control scale. | ROTTER´s locus of control scale test will be used before, at 6, 12, and 24month after bariatric surgery and the scores will be compared. The investigators will evaluate the existence of correlations with the BMI, EWL% and TWL changes. COPE is a quantitative scale which a total score ranging between 0-29 points. The cut-off value <15 defines the internal locus of control. | 24month | 
| Evaluation of neuropsychological scores before and after bariatric surgery: YALE food addiction. | YALE food addiction scale test will be used before, at 6, 12, and 24month after bariatric surgery and the scores will be compared. The investigators will evaluate the existence of correlations with the BMI, EWL% and TWL changes. There is a direct relation between the score and the food addiction, is a quantitative scale but there is no clear cut-off. There will be evaluated the changes in the score at 6,12, and 24 month after the bariatric surgery, comparing with baseline. The highest the score, the higher the food addiction. | 24month | 
| Evaluation of neuropsychological scores before and after bariatric surgery:The Bariatric Analysis and Reporting Outcome System (B.A.R.OS). | B.A.R.O.S test will be used before, at 6, 12, and 24month after bariatric surgery and the scores will be compared. The investigators will evaluate the existence of correlations with the BMI, EWL% and TWL changes. B.A.R.O.S. is a quantitative questionnaire evaluating the quality of life after the bariatric surgery. The scale ranges between 0 and 9. The higher the score the highest the quality of life of the patient. | 24month | 
| Evaluation of neuropsychological scores before and after bariatric surgery: The State-Trait Anxiety Inventory (STAI). | STAI anxiety questionnaire evaluates the degree of the anxiety of the patient and will be used before, at 6, 12, and 24month after bariatric surgery and the scores will be compared. The investigators will evaluate the existence of correlations with the BMI, EWL% and TWL changes. The score ranges between 0 and 60. A cut-off value> 19 is considered pathological anxiety. | 24month | 
| Evaluation of neuropsychological scores before and after bariatric surgery: WPAI (working productivity questionnaire). | WPAI questionnaire will be used before, at 6, 12, and 24month after bariatric surgery and the results will be compared. The investigators will evaluate the existence of correlations with the BMI, EWL% and TWL changes. There is a qualitative score, evaluating the working status of the patient: retiree, active, off-work>6month, unemployed, permanent occupational disability. Percentages of each category will be evaluated at each time. Ej: % of unemployed, etc. | 24month | 
| Evaluation of neuropsychological scores before and after bariatric surgery: Beck Depression Inventory (BDI) | BDI evaluates if depression exists and its degree. It will be used before, at 6, 12, and 24month after bariatric surgery and the results will be compared. The investigators will evaluate the existence of correlations with the BMI, EWL% and TWL changes. The score ranges between 0-40. 0-10: normal; 10-16 mild emotional; 17-20: borderline clinical depression; 21-30 moderate depression; 31-40 severe depression. | 24month | 
| Evaluation of the congnitive function before and after bariatric surgery | Minimental State Evaluation Test and Montreal Cognitive Assessment test will be used before and at 12 and 24 month after bariatric surgery | 24 month | 
| Evaluation of the utility of the retinal function evaluation in the detection of cognitive disfunction before and after bariatric surgery | Retinal microperimetry using MAIA 3rd generation microperimeter will be used before and at 12 and 24 month after the bariatric surgery | 24 month | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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morbid obesity, bariatric surgery, psychological profile