How Altered Gut-Brain-Axis Influences Food Choices: Part 2 (BrainFood)

Study Overview
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Brief Summary
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Obesity is currently one of the most substantial health burdens. Due to the production of marked and sustained weight loss, bariatric surgery is an increasingly used therapeutic modality to combat obesity and its comorbidities. Surgical rearrangement of the gastrointestinal tract remarkably alters metabolism and hormones acting on neurological and hypothalamic signalling, involved in food decision-making and eating behaviour. In this context, many patients who underwent bariatric surgery self-report changes in appetite, satiety and food preferences. Furthermore, new gut hormone-based (e.g. GLP-1 receptor agonist or GLP-1-RA) pharmacotherapies which mimic the effect of bariatric surgery show impressive efficacy on weight reduction by modulation of food behaviour. However, the mechanisms of such functional changes, and how they relate to food decision-making and food purchase behaviour remain unknown. In Part 2 of the BrainFood-project, the investigators propose a novel approach using digital receipts from loyalty card to unravel the effect of obesity treatments (surgical and non-surgical) on eating and food purchase behaviour in daily life.

Detailed Description
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The overall aim of this project is to elucidate the changes in food behaviour among obese adults undergoing obesity treatments. The main objective is to observe the effect of obesity treatments on food purchase behaviour using digital receipts from grocery shopping. The investigators hypothesize that bariatric surgery leads to changes in food purchase behaviour in obese adults. The further objective is to compare food purchase behaviour between obese adults against values of an existing reference population, and to assess whether these differences tend to be reduced after the start of the treatment among obese participants.

Official Title
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How Altered Gut-Brain-Axis Influences Food Choices. (BrainFood) Part 2: Digital Receipts

Conditions
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Food Preferences, Obesity

Intervention / Treatment
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* Other: Questionnaire (Survey and Food Frequency Questionnaire (FFQ))
* Other: Collection of digital receipts from grocery shopping


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Female and male subjects aged 18 years or older Proficient in German (including written) BMI≥30kg/m2 or BMI≥28kg/m2 with adiposity-related comorbidities (prediabetes, type 2 diabetes mellitus, hypertension, dyslipidemia) Referred for obesity treatment or who started obesity treatment within 6 months (surgical or non-surgical) Primary grocery shopping at the Swiss biggest grocery retailers (Coop, Migros), and regularly using a loyalty card (Cumulus and/or Supercard) Exclusion Criteria: Incapacity to give informed consent Primary shopping in other food retailers (e.g. Aldi, Lidl, outside of Switzerland, etc.)

Ages Eligible for Study
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Minimum Age: 18 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 |
| --- | --- |
| Obesity treatment Group<br>60 (minimum) to 150 (maximum) overweight/obese adults referred for or who started obesity (surgical or non-surgical) treatment within 6 months | Other: Questionnaire (Survey and Food Frequency Questionnaire (FFQ))<br>* Each participant will be asked to fill a web-based questionnaire that captures sociodemographic, lifestyle, physical and mental health information (Survey) and dietary intake patterns (FFQ). This will be done pre-treatment (only for those included pre-treatment), 6 months after the start of obesity treatment, 1 year after the start of the treatment and then yearly until 5 year after the start of the treatment.<br>Other: Collection of digital receipts from grocery shopping<br>* Participants will create their BitsaboutMe-account (GDPR-compliant data sharing platform from Bern, Switzerland) with the help of study team members. Data from digital receipts will be obtained from Migros Cumulus and Coop Supercard via their BitsaboutMe-account. The data collection allow retrospective digital receipts collection for up to 2 years and automatically continuous collection during study duration. GDPR: General Data Protection Regulation<br>|
| Control Group<br>Comparison of food purchase behaviour with control subjects will be performed using an already existing cohort from a previous study. This does not required recruiting control subjects. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in food purchase behaviour on the basis of the Healthy Trolley Index (HETI) | Changes in food purchase behaviour pre-treatment will be compared to post-treatment on the basis of the HETI, an objective and validated, nutrient-based, healthy shopping scoring system. | Pre-treatment until 5 years after start of obesity treatment | 
| Changes in food purchase behaviour on the basis of the Grocery Purchase Quality Index (GPQI) | Changes in food purchase behaviour pre-treatment will be compared to post-treatment on the basis of the GPQI, an objective and validated, nutrient-based, healthy shopping scoring system. | Pre-treatment until 5 years after start of obesity treatment | 
| Changes in food purchase behaviour on the basis of food groups | Changes in food purchase behaviour pre-treatment will be compared to post-treatment on the basis of food groups like vegetables, wholegrain, fruits, sweets and meats. | Pre-treatment until 5 years after start of obesity treatment | 
| Changes in food purchase behaviour on the basis of nutrition facts | Changes in food purchase behaviour pre-treatment will be compared to post-treatment on the basis of nutrition facts like energy (kcal), carbohydrates, sugars, added sugars, protein, fat, saturated fat, dietary fibre and salt. | Pre-treatment until 5 years after start of obesity treatment | 
| Changes in food purchase behaviour on the basis of the Nutri-Score | Changes in food purchase behaviour pre-treatment will be compared to post-treatment on the basis of the Nutri-Score, representing the nutritional quality of products. The Nutri-Score is based on a discrete continuous scale from -15 (most healthy) to 40 (least healthy). The score is then transcribed into five colour categories (A-E, ranging from bright green (most healthy) to red (least healthy)). | Pre-treatment until 5 years after start of obesity treatment | 
| Food purchase behaviour on the basis of the Healthy Trolley Index (HETI) | HETI will be compared between obesity treatment group and control group | Pre-treatment until 5 years after start of obesity treatment | 
| Food purchase behaviour on the basis of the Grocery Purchase Quality Index (GPQI) | GPQI will be compared between obesity treatment group and control group | Pre-treatment until 5 years after start of obesity treatment | 
| Food purchase behaviour on the basis of food groups | Food groups will be compared between obesity treatment group and control group | Pre-treatment until 5 years after start of obesity treatment | 
| Food purchase behaviour on the basis of nutrition facts | Nutrition facts will be compared between obesity treatment group and control group | Pre-treatment until 5 years after start of obesity treatment | 
| Food purchase behaviour on the basis of the Nutri-Score | Nutri-Score will be compared between obesity treatment group and control group | Pre-treatment until 5 years after start of obesity treatment | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Bariatric surgery, Food preferences, Food behaviour, Digital receipts, Grocery Shopping, Obesity treatment, GLP-1 receptor agonist