Use of Very Low Calorie Diet Preoperatively to Bariatric Surgery

Study Overview
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Brief Summary
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To investigate use of Very Low Calorie Diet preoperatively to bariatric surgery can optimize weight loss prior to surgery and increase the patients' satisfaction.

Detailed Description
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In this project the investigators want to develop an effective Very Low Calorie Diet (VLCD) treatment prior to bariatric surgery, which is optimized in relation to the size and speed of the weight loss as well as in terms of satisfaction both for the patients as for the health care professionals. Thus the investigators will randomize 500 patients to either VLCD or standard care prior to bariatric surgery. The investigators aim to optimize preoperative and the operative course for patients, who are offered bariatric surgery.

Official Title
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Use of Very Low Calorie Diet Preoperatively to Bariatric Surgery

Conditions
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Bariatric Surgery Candidate, Very Low Calorie Diet, Weight Loss

Intervention / Treatment
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* Dietary Supplement: VLCD
* Dietary Supplement: Standard care


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Eligible for bariatric surgery Exclusion Criteria: -

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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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Very Low Calorie Diet (VLCD)<br>VLCD | Dietary Supplement: VLCD<br>* Advice regarding VLCD<br>|
| Placebo Comparator: Standard care<br>Standard care | Dietary Supplement: Standard care<br>* Standard dietary advice for weight loss before bariatric surgery<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Weight loss |  | 8 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Patient quality of life measured using the Short Form-12 (SF-12) questionnaire | Scores range from 0 to 100, with higher scores indicating better physical and mental health functioning | 8 weeks and 1 year | 
| Positive and negative consequences of the two weight loss treatments identified by the surgeon, using a questionnaire developed for the purpose | In the questionnaire, the surgeon will be asked questions on details on the surgery, including duration of surgery and complicating factors. | 30 days after surgery | 
| Use of health care services assessed by a medical chart review | We will assess the number of health care contacts for each patient. | 30 days after surgery | 
| Severity of complications assessed by a medical chart review. | We will define the severity of the contacts based on whether they are outpatient or inpatient contacts. | 30 days after surgery | 
| Presence of eating disorders | The patients will be asked to complete the Eating Disorder Examination Questionnaire (EDE-Q) to assess whether diorderes eating is present. Scores range from 0 to 6 and a score of 4 and above indicate disordered eating. | At baseline |