Omega Loop Versus Roux-en-Y Gastric Bypass

Study Overview
=================
Brief Summary
-----------------
Several prospective trials and metaanalysis have demonstrated the superiority of bariatric surgery on the medical treatment of obesity. The Roux-en-Y Gastric ByPass (RYGBP) procedure has been practiced for more than 30 years, and is the procedure of choice for morbidly obese with metabolic disorders in most of the reference centers. Nevertheless, the RYGBP is a technically demanding procedure with a learning curve of more than 75 cases. The complication rate is around 10% in expert centers. More recently another procedure has been described which seems as efficient on weight loss and co-morbidities as the RYGBP, with the advantage of being less technically difficult and less morbid, especially for multi-complicated obese and/or the super obese. It consists of a unique gastro-jejunal anastomosis between a long gastric pouch and a jejunal Omega loop. However, this procedure could be at risk of biliary reflux and anastomotic ulcers with dysplastic changes of the gastric and esophageal mucosa. As a result, the Omega loop bypass (OLB) has only been developed by a few teams and remains a controversial subject, particularly as only one monocentric randomized trial has compared it to the RYGBP, which is remains the gold standard. The first litterature results show similar or even better weight loss efficiency than RYGBP with a better feasibility. The early complication rate seems lower, but there are still insufficient data on long term morbidity and biliary reflux consequences. By performing a randomized and prospective comparison of OLB to RYGBP, the aim of the investigators study is to analyze the weight loss efficiency, the morbidity and mortality, the feasibility, and the quality of life of both techniques, in order to validate the Omega loop bypass as a procedure of choice in bariatric surgery Hypothesis : The OLB, while being as efficient as RYGBP on weight loss and metabolic complications, could be less morbid.

Official Title
-----------------
Prospective Multicentric Randomized Trial of Efficiency and Safety of Laparoscopic Omega Loop Bypass Versus Roux-en-Y Gastric Bypass

Conditions
-----------------
Obesity

Intervention / Treatment
-----------------
* Procedure: Laparoscopic Mini-gastric bypass
* Procedure: Procedure of reference in bariatric surgery


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Aged between 18 and 65 years old Morbid obesity with BMI ≥ 40 kg/m2 or BMI ≥ 35 kg/m2 associated with one or more co-morbidities (type 2 diabetes, arterial hypertension, sleep apnea, dyslipidemia, arthritis) Patient who has benefited from an upper GI endoscopy with biopsies Patient who has benefited from a pluridisciplinary evaluation, with a favorable opinion for a gastric bypass Patient who understands and accepts the need for a long term follow-up Patient who agrees to be included in the study and who signs the informed consent form Patient affiliated to a healthcare insurance plan Exclusion Criteria: History of esophagitis on upper GI endoscopy (Los Angeles classification) Severe gastroesophageal reflux disease (GERD), resistant to medical treatment Presence of dysplastic modifications of the gastric mucosa or a history of gastric cancer, on upper gastrointestinal endoscopy. Presence of Helicobacter Pylori resistant to medical treatment Presence of an unhealed gastro-duodenal ulcer or an ulcer diagnosed less than 2 months previously History of previous bariatric surgery (gastric band, sleeve gastrectomy, vertical banded gastroplasty) Presence of a severe and evolutive life threatening pathology, unrelated to obesity Presence of chronic diarrhea (≥ 3 loose or liquid stools per day, over a period of more than 4 weeks) Pregnancy or desire to be pregnant during the study Binge eating disorders or other eating disorders according to DSM V criteria Mentally unbalanced patients, under supervision or guardianship Patient who does not understand French/is unable to give consent Patient not affiliated to a French or European healthcare insurance Patient who has already been included in a trial which has a conflict of interests with the present study

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

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Laparoscopic Omega Loop Bypass<br>Laparoscopic Mini-gastric bypass | Procedure: Laparoscopic Mini-gastric bypass<br>* The laparoscopic Omega Loop Bypass will consist of: a long gastric tube, stapled approximately 1.5 cm from the left of the lesser curvature of the antrum to the angle of His a narrow gastric tube will be calibrated to be approximately 1.5 cm wide an Omega loop of 200 cm a unique gastro-jejunal anatomosis of 200cm from the ligament of Treitz, using a linear stapler<br>|
| Active Comparator: Laparoscopic Roux-en-Y Gastric ByPass<br>Procedure of reference in bariatric surgery | Procedure: Procedure of reference in bariatric surgery<br>* The laparoscopic Roux-en-Y Gastric Bypass will consist of: a small gastric pouch (about 30cc) an antecolic alimentary limb a gastro-jejunal anastomosis using a linear stapler a 150cm long alimentary limb a 50cm biliary limb a latero-lateral jejuno-jejunal anastomosis closure of the mesenteric defects<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Weight loss assessment according to Excess BMI Loss percentage (EBL%) | Weight loss assessment according to Excess BMI Loss percentage (EBL%), calculated using the following formula: ((BMI 2 years after surgery - initial BMI) / (initial BMI - 22.5)) X 100 | 2 years after surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Weight loss according to absolute weight loss (aWL in kg), Excess Weight Loss percentage (EWL%), EBL% |  | 1, 3, 6, 12, 18 and 24 months after surgery | 
| Waist size reduction according to absolute waist size (in cm) |  | 1, 3, 6, 12, 18 and 24 months after surgery | 
| Medical and surgical complication rates | Medical and surgical complication rates (anastomotic leaks, biliary reflux, bowel obstruction, anastomotic ulcers, anastomotic stenosis, internal hernia, chronic gastritis, esophagitis, iron deficiency anemia …) | 1, 12 and 24 months after surgery | 
| Type and severity of complications | Type and severity of early and late complications for each procedure, according to the Dindo-Clavien classification | During the month following surgery (for early complications) and from one month to 24 months postoperatively (for late complications) | 
| Operative time | Operative time (expressed in minutes) | Recorded on the day of surgery (Day 0) | 
| Mean length of stay | Mean length of stay based on the number of days of hospitalization from surgery (Day of surgery = D0) until the end of hospitalization | Average period of 5 days from surgery (Day of surgery = D0) until the end of hospitalization, recorded on Visit 4 (Month1 +/- 10 days) | 
| Patient's quality of life | Patient's quality of life score according to the IWQOL questionnaire and the BAROS questionnaire adapted to bariatric surgery | The day before surgery (D-1) and 6, 12 and 24 months after surgery | 
| Metabolic and lipid profile | Metabolic profile of glucose homeostasis and the lipid profile according to antidiabetic and anitilipidemic treatments, HbA1c level, fasting glycemia, HDL, LDL and TG. | During the period of inclusion (D-60 to D-2) and at 6, 12 and 24 months after surgery | 
| Dumping syndrome and hypoglycemia symptoms | Dumping syndrome and hypoglycemia symptoms will be assessed using the Sigstad questionnaire | At 1, 3,6,12,18 and 24 months after surgery | 
| Gastroesophageal reflux | Gastroesophageal reflux assessed by items 5 and 27 of the GIQLI questionnaire | The day before surgery (Day-1) and 6, 12, and 24 months after surgery | 
| Modifications of the gastric and esophageal mucosa | Histological modifications of the gastric and esophageal mucosa, based on upper GI endoscopy with biopsies | 2 years after surgery | 
| Frequency of diarrhea | Frequency of diarrhea based on items 7, 30, 31 and 36 of the GIQLI questionnaire | The day before surgery (day-1) and 6, 12, and 24 months after surgery | 
| Nutritional status | Nutritional status, assessed by PTH, vitamin B1, B9, B12, and D levels before and 12 and 24 months after surgery and assessed by hemoglobin, albumin, prealbumin, ferritin, saturation coefficient, before and 6, 12 and 24 months after surgery . | During the period of inclusion (D-60 to D-2) and 6, 12, and 24 months after surgery (The 24-hour steatorrhea will be quantified at 6 months). | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
Obesity -, Bariatric surgery, Gastric bypass