Prehabilitation in Bariatric Surgery

Study Overview
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Brief Summary
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Obesity is a major public health problem in our region and constitutes a priority of the Canary Islands Health Plan. Bariatric surgery is the most effective intervention in the treatment of obesity and its complications. However, people with obesity have high surgical risk and long-term outcomes are related to pre-surgical weight loss. In patients currently on the bariatric surgery waiting list, a randomized controlled trial will be performed in which two group interventions will be compared. One of the interventions (standard), will consist of educational modules in food and exercise, combined with cognitive-behavioral therapy. In the other, a specific training (prehabilitation) will be added to encourage physical activity and the conditioning of inspiratory muscles. The pre-surgical weight loss (principal outcome) will be compared between groups, as well as the evolution of the complications of obesity, the functional status of the patients, their physical activity, quality of life, immediate complications of surgery and days of admission.

Detailed Description
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Obesity is a major public health problem, responsible for an increased risk of hypertension, obesity, dyslipidemia, type 2 diabetes, cardiovascular disease, some types of cancer, psychiatric diseases and mortality. Bariatric surgery has proven to be the most effective method for reducing weight and related comorbidities in patients with morbid obesity. However, pre-surgical weight loss reduces postsurgical complications. In addition, weight loss before surgery seems to be the only factor positively associated with post-surgical weight loss, and this effect seems to be more pronounced in patients with BMI> 45 kg / m2. Pre-operative physical conditioning (prehabilitation) can improve the patient's functional capacity before major surgery. Most studies showing this have been conducted in orthopedic surgery and abdominal cancer surgery. There are very few studies that evaluate prehabilitation in patients undergoing bariatric surgery. Objective Comparison of a multidisciplinary group intervention with another one to which specific training focused on increasing physical activity is added, in patients on the surgical waiting list for bariatric surgery in a randomized controlled trial. Methods Design Randomized, controlled parallel group, clinical trial. Intervention Duration: 4-month intervention, with biweekly 2,5-hour group sessions, followed by a monthly reinforcement session of 1h until surgery. Intervention A: Educational program and cognitive-behavioral intervention (control group) Intervention B: Educational program and cognitive-behavioral intervention, with specific training aimed at increasing physical activity, functional capacity and conditioning of the respiratory muscles (intervention group). Study population The recruitment of the participants will be made from the waiting list of bariatric surgery (obesity II-IV), selecting patients with estimated waiting time above 4 months. Patients will be excluded if any reason for inadequate follow-up is identified, according to the investigators criteria. Ethical aspects The design and execution of this study will be done in accordance with the Declaration of Helsinki and the homogenized European guidelines of good clinical practice. Before their participation, the patients will sign an informed consent form. The protocol has been approved by the local ethics committee Sample size Based on the size of the waiting list for bariatric surgery, with a mean duration of 17 months, and that the intervention is considered feasible on two groups of 10 people, in parallel, in each branch, (a weekly session of 2h per nutrition nurse, with support from additional professional). Starting with a pilot group of each intervention and taking into account an overlap between them, in 18 months about 60-80 patients could be included in total. With 80 patients included, without losses, and assuming a standard deviation of weight of 11Kg, and for a bilateral p <0.05 a difference between groups of 7 and 8Kg, with a statistical power of 80 and 90%, respectively. If we assume a standard deviation of 6Kg, as shown by other studies, the detectable difference would be reduced to about 4Kg. Statistical analysis A descriptive analysis of the baseline situation will be made. The qualitative variables are expressed as a percentage, quantitative, as mean (SD) or median, according to if its distribution is normal or not, respectively. Comparisons will be made between treatment groups, using chi squared for qualitative variables and Student's t or Mann Whitney's U for quantitative variables. The analysis of results will be done by intention to treat analysis. That is, all patients who have baseline data and have been randomized, will be included, regardless of their subsequent attendance to the Program.

Official Title
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Prehabilitation in Bariatric Surgery: a Randomized Controlled Clinical Trial

Conditions
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Obesity, Bariatric Surgery Candidate

Intervention / Treatment
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* Behavioral: Prehabilitation
* Behavioral: Control


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: People with obesity (type II-IV), on the waiting list for bariatric surgery in the Complejo Hospitalario Universitario Materno-infantil de Las Palmas Exclusion Criteria: any factor that, in the opinion of the researchers, limits the ability to monitor the intervention (language barrier, ...).

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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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Randomized, controlled clinical trial, which will compare two group interventions in patients on the waiting list for bariatric surgery. Duration: 4-month intervention, with biweekly 2-hour group sessions c / un, followed by a monthly reinforcement session of 1h until surgical intervention. Intervention A: Educational program and cognitive-behavioral intervention (group control) Intervention B: Educational program and cognitive-behavioral intervention, with specific training aimed at increasing physical activity, capacity functional and conditioning of the respiratory musculature (group of intervention).
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Intervention<br>Educational program and cognitive-behavioral intervention. The patient receives training in nutrition and cognitive-behavioral therapy, with specific training aimed at increasing physical activity, functional capacity and conditioning of the respiratory musculature (prehabilitation by a physiotherapist) | Behavioral: Prehabilitation<br>* Prehabilitation: The intervention of a physiotherapist will be added to the components of the control group. Patients will receive practical instructions on aerobic and resistance physical activity, as well as training of their inspiratory muscles.<br>* Other names: Inspiratory muscle training, physical activity.;|
| Active Comparator: Control<br>Educational program and cognitive-behavioral intervention. The patient receives training in nutrition and cognitive-behavioral therapy, as well as standard instructions to increase physical activity. | Behavioral: Control<br>* Standard group intervention. Educational program and cognitive-behavioral intervention. The patient receives training in nutrition and cognitive-behavioral therapy, as well as standard instructions to increase physical activity.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Weight change | Increase (or decrease) in weight between the start of the program and the time of surgery (measured on a calibrated scale, with Maximum increments of 0.1Kg, under the same conditions, without footwear and with light clothing) | 4-6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Body mass index | Calculated as weight (in Kg) divided by the squared height (in meters) | 4-6 months | 
| Body composition | Percentage of body fat and lean mass estimated by bioimpedance | 4-6 months | 
| Associated complications-Blood pressure | Systolic and diastolic blood pressure (in sitting position, after 5 minutes of rest, using a manual sphygmomanometer, with a cuff adapted to thebrachial circumference of the patient) | 4-6 months | 
| Associated complications-lipids | total cholesterol, HDL cholesterol, LDL cholesterol, triglycerides (automatic methods) in mg/dl colorimetric tests) | 4-6 months | 
| Associated complications-glucose metabolism | HbA1c (HPLC standardized against DCCT-IFCC) | 4-6 months | 
| Associated complications-treatments | Number of drugs used for associated cardiovascular risk factors | 4-6 months | 
| Associated complications-liver enzymes | AST, ALT, GGT (automatic methods) | 4-6 months | 
| Adherence to the intervention | Attendance at the sessions (number of sessions attended) programmed. | 4-6 months | 
| Physical activity-steps | Registered by pedometers (number of steps/week) | 4-6 months | 
| Physical activity-self reported | International Physical Activity Program (IPAQ) questionnaire | 4-6 months | 
| Eating patterns-Adherence to Mediterranean diet | Validated Food questionnaire (simplified questionnaire of 14 questions of adherence to the diet Mediterranean diet of PREDIMED) . Higher scores indicate higher adherence | 4-6 months | 
| Eating patterns-eating disorders | Standardised questionnaire (bulimia and binge disorders of the EDI -Eating Disorder Inventory) | 4-6 months | 
| General health status | EQ-5D questionnaire (higher scores indicate better self-perceived health status) | 4-6 months | 
| Emotional state | Hospital scale of anxiety and depression (HADS) | 4-6 months | 
| Subjective evaluation of satisfaction, perceived effort and motivation | Development of a specific questionnaire with Likert type scale for the patient to score 1 to 10 each of the 3 items. | 4-6 months | 
| Functional capacity-walk test | 6-minute walk test (TM6): meters completed during the test | 4-6 months | 
| Functional capacity- grip strength | Grip test: hand grip dynamometer and the grip strength in both hands, indicating the dominant one. | 4-6 months | 
| Functional capacity-respiratory muscle strength | Maximum inspiratory pressure (PIM) and expiratory pressure (PEM) | 4-6 months | 
| Functional capacity-plethysmography | Lung volumes, VR (residual volume) and CRF (functional residual capacity) in ml | 4-6 months | 
| Functional capacity-Spirometry | Forced spirometry: Forced expiratory volume in 1 second (FEV1), Functional Vital Capacity (FVC) in ml. Tiffenau index will be calculated. Mesoespiratory flows | 4-6 months | 
| Functional capacity-sleep apnea questionnaire | Stop-bang screening questionnaire for sleep-related breathing disorders. | 4-6 months | 
| Functional capacity-sleep apnea polygraph | Home cardiorespiratory polygraphy for diagnosis of disorder | 4-6 months | 
| Surgical complications | Early post-surgical complications (<30 days) | 5-7 months after start of intervention | 
| Surgery-length of admission | Post-surgical length of stay (stratified by surgical technique). | 5-7 months after start of intervention | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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nutrition, physical activity, prehabilitation