Effect of Gastric Bypass Surgery on Brain Responses

Study Overview
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Brief Summary
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After obesity surgery gastric bypass (GBP) patients usually lose more than 50% of its former preponderance in relative short time (  2 years). But knowledge of the underlying biological mechanisms of decline in body weight is still inadequate. This project intends to examine patients' background activity in the brain (i.e. the resting state activity) and brain volume using MRI both before and one year after surgery.

Detailed Description
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We will also investigate whether hormonal changes in response to food intake after obesity surgery is associated with patients' impulsive control when exposed to pictures of food in the MRI.

Official Title
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The Effects of Bariatric Surgery on Impulsivity and Attentional Bias to Food Cues

Conditions
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Obesity, Hormone Responses, Cognitive Health

Intervention / Treatment
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* Procedure: Bariatric surgery
* Behavioral: Brain activity in resting state
* Behavioral: Memory performance


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: female right-handed scheduled for bariatric surgery in the Academic Hospital of Uppsala, Sweden Exclusion Criteria: undergone more than one bariatric surgery suffer from mental disorders (depression, phobias, etc.) that can not be controlled with treatment.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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Female

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: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Bariatric surgery<br>patients participating in the intervention group , i.e. assessing effects of bariatric surgery on: Brain activity in resting state Memory performance | Procedure: Bariatric surgery<br>* Gastric bypass surgery<br>Behavioral: Brain activity in resting state<br>* Measure of activity in brain networks during resting state<br>Behavioral: Memory performance<br>* Assess concentration in 2D-location task (i.e. memory game)<br>|
| Active Comparator: Control<br>Patients in the control group will not undergo surgery during study. These patients will be examined twice: 9 weeks before the operation (i.e. clinical intervention to reduce body weight has not started). after 4 weeks of low-calorie diet (which will be a week before their surgery, when patients are in a catabolic metabolism because they eat much less energy than is needed) to assess effect of acute weight loss on: Brain activity in resting state Memory performance | Behavioral: Brain activity in resting state<br>* Measure of activity in brain networks during resting state<br>Behavioral: Memory performance<br>* Assess concentration in 2D-location task (i.e. memory game)<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in background activity in the brain (resting state activity) after bariatric surgery | Brain's basic activity and structure will be measured on 3 occasions: 4 weeks before bariatric surgery, 4 weeks after surgery and 1 year after surgery, using fMRI. | 1 year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in response inhibition after bariatric surgery | Inhibitory control to food cues will be measured on 3 occasions: 4 weeks before bariatric surgery, 4 weeks after surgery and 1 year after surgery, using a NoGo-Go task. | 1 year | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Bariatric surgery, Cognition, Satiety hormones, Brain networks, Inhibitory control, Food intake