Morbid Obesity

Metabolic and bariatric surgery (MBS) is the most effective durable treatment for severe obesity, yet a clinically meaningful proportion of patients experience recurrent weight gain after an initially successful operation. Until recently, research and care in this area were limited by the absence of standardized definitions: reported prevalence of weight recurrence ranged from under 10% to over 90% depending on the metric and threshold applied, and treatment decisions varied by provider. In 2026, an international two-round modified Delphi study of 66 experts across surgery, obesity medicine, gastroenterology, endocrinology, dietetics, and psychology (Wills et al.) established consensus definitions. The consensus specifies: (i) percentage total weight loss (%TWL) as the preferred measurement approach (94.6% agreement); (ii) surgical non-response as \<10% TWL at 12 months (73.0%); (iii) recurrent weight gain as regain of more than 25% of lost weight from nadir (70.3%); and (iv) a change of up to 10% in percentage excess weight loss from nadir as a normal physiologic fluctuation not requiring intervention (83.8%). The consensus also endorsed 'suboptimal' as the preferred terminology for poor surgical response and reached unanimous agreement that anti-obesity medications may appropriately be prescribed by specialists in this population. These definitions supersede the heterogeneous thresholds used previously, including the \>30% regain threshold of the 2024 IFSO Delphi, and are adopted throughout this protocol. Both IFSO and ASMBS now formally support pharmacotherapy as a therapeutic option for weight recurrence after MBS. The 2024 IFSO international consensus on obesity management medications in the context of MBS reinforces this pathway: at 92% agreement, medications should generally be considered before revisional surgery for recurrent weight gain; at 100%, medication efficacy appears broadly preserved after MBS; and at 97%, no clear increase in adverse effects after MBS has been demonstrated. RESURGE supplies the randomized evidence behind the first of these statements.

Recurrent weight gain affects 15% to 40% of patients after metabolic and bariatric surgery (MBS). SG is the most performed operation worldwide, and long-term regain after SG is well documented. A 2026 international Delphi consensus has now standardized the definition. This trial uses that definition. So does our companion trial, RESURGE. We have two real treatments. Both work. Neither is enough. Conversion of SG to RYGB gives around 20% additional total weight loss at 12 months across all indications, and less when the indication is poor weight response rather than reflux. Drug therapy also works after MBS. Liraglutide beat placebo by about 8 percentage points in the BARI-OPTIMISE randomized trial. Semaglutide gives around 11% total weight loss and tirzepatide around 14% in pooled retrospective data, including specifically after SG. Most patients do not return to their nadir weight with either option alone. The field is already comparing the two strategies, but only retrospectively. Two 2025 multicenter cohorts compared conversion against GLP-1 therapy after SG. These studies cannot control diet, exercise, supplementation, co-medication, or adherence. They cannot settle the question. The societies agree on the pathway but admit the evidence is weak. The 2024 IFSO position statement and the 2026 ASMBS statement say the same thing: work up the anatomy first; operate when there is a structural problem; consider medical therapy when there is not; and consider combining drug therapy with revision. The 2024 IFSO international consensus goes further: with 92% agreement, it states that medications should generally be considered before revisional surgery for recurrent weight gain. Every one of those recommendations rests on consensus and retrospective data. None rests on a randomized trial. This protocol is that trial.

Patients with BMI 60 kg/m² or higher are the hardest operations in bariatric surgery. Thick abdominal wall, massive hepatomegaly, reduced working space, fragile fatty tissue, higher conversion and complication rates. Every bariatric surgeon knows this group. Almost no trial recruits it. The standard answer is a short liver-reduction diet before surgery. It helps, but the effect is modest, hard to tolerate, and short-lived. GLP-1-based drugs now produce far larger and better-tolerated weight loss and are already being given before surgery in routine practice, without trial evidence. Retrospective series show more preoperative weight loss and no obvious harm, and no more than that (Obesity Research \& Clinical Practice 2026). A 2023 review of drugs on the surgical waiting list found that GLP-1 receptor agonists had never been evaluated for the preoperative indication at all. Two registered trials are now adjacent to this question, and we cite both. The PreMO pilot randomizes 50 patients to open-label preoperative tirzepatide versus standard care, with tissue inflammation as the scientific focus (PMID 41643256; NCT06721507). A three-arm trial before one-anastomosis gastric bypass compares tirzepatide, ketogenic diet, and standard care, with weight loss at one year as primary (NCT07622992). Neither is blinded. Neither recruits BMI 60 and above. Neither measures whether the drug actually makes the operation easier and safer. The 2024 IFSO international consensus reached 100% agreement that evidence is insufficient to recommend routine preoperative medication, that use must be individualized, and that more research on benefits, risks, and outcomes is required; it also agreed, at 97%, that adequate protein and resistance exercise must accompany any preoperative drug treatment (PMID 39612579). This trial is the research that consensus calls for, and its preoperative program is built to the 97% requirement.

Every course of obesity pharmacotherapy ends. Cost, supply, pregnancy plans, side effects, or the patient's own wish. In Egypt, cost alone makes discontinuation the rule, not the exception. Yet the entire evidence base describes what happens when the drug stops, and none of it tests how to stop. Abrupt withdrawal fails predictably. One year after stopping semaglutide, STEP 1 extension participants had regained two thirds of their lost weight. SURMOUNT-4 showed the same pattern after tirzepatide withdrawal, and meta-analysis confirms it across agents. After MBS specifically, stopping GLP-1 therapy is likewise followed by regain. The guidelines say: do not stop at all. The 2026 ADA and Obesity Association Standards strongly recommend continuing medication through maintenance, and the 2024 IFSO consensus agrees that when medication is needed to hold the benefit after MBS, ongoing treatment is probably necessary, while stating, at 94% agreement, that intermittent therapy and dose-reduction strategies require research. Our patients cannot follow the first recommendation. Cost decides for them. This trial is the research the second sentence asks for: the evidence for the moment when continuing is not an option. Clinicians already taper, on no evidence. A 2025 expert commentary describes 8-to-12-week dose reductions in routine practice and states plainly that the approach is anecdotal and untested (Obesity and Endocrinology 2025). Practice has run ahead of the trial. The general-population trial now exists, and we cite it rather than duplicate it. The REST trial has registered exactly this comparison, gradual 16-week dose reduction versus abrupt cessation, in non-surgical patients with obesity. No such trial exists after MBS.

Roughly one patient in five never reaches the expected weight loss after MBS, and long-term regain after SG is well documented. These patients are identifiable at the 12-month visit. Today they are watched, coached, and treated only when failure is established. Whether the drug works in this group is no longer the question. BARI-STEP, published this year, randomized 70 patients with less than 20% weight loss after gastric bypass (including one-anastomosis) or sleeve gastrectomy, a mean of seven years after surgery, to semaglutide 2.4 mg or placebo: 18.0% loss versus 0.4% gain at 68 weeks, an adjusted difference of 19.1 percentage points. Its population was mixed, 55.7% with recurrent weight gain and 44.3% with suboptimal initial response, and its exploratory comparison found no difference in drug response between the two presentations. BARI-OPTIMISE showed the same direction with liraglutide, as did a randomized trial after gastric banding. Efficacy is settled. Timing is not. BARI-STEP recruited patients a mean of seven years past surgery, after failure had hardened. No trial has tested treating at first recognition, the 12-month visit, against the current standard of structured waiting. The field's own reviews name timing and duration as the open questions. The 2024 IFSO international consensus reached 100% agreement that medication after MBS should generally be withheld until the weight plateau, and 100% agreement that adding it for a suboptimal response can then improve outcomes. That is exactly our immediate arm: treat at the plateau, at first recognition. The triggered arm is what clinics actually do: wait for established failure. Both positions rest on expert agreement, not on a trial. This is the randomized test of the consensus pathway. A registered open-label pilot starts tirzepatide at 12 or 18 months but is small, unblinded, and not a strategy comparison. The 2026 consensus draws the line for us, and this protocol respects it. The Delphi panel defined surgical nonresponse as less than 10% TWL at 12 months, defined recurrent weight gain as regain of more than 25% of lost weight from nadir, and treated a 10% swing in %EWL from nadir as normal physiologic fluctuation. It gave no 12-month label at all to the patient with 10 to 19.9% TWL, and the IFSO Delphi consensus expects the weight nadir up to 2 years after surgery (Obes Surg 2023). So a patient at 14% TWL at one year may still be on the way down, and calling that failure would be wrong. The protocol therefore splits eligibility into two tiers. Below 10% TWL at 12 months: consensus-defined nonresponse, randomized at once, waiting adds nothing. 10 to below 20% TWL: randomized only after a documented plateau, defined in Section 4, with a hard cap at month 18 so waiting cannot drift into neglect. Randomization is stratified by tier, and results are reported by tier.

Morbid obesity, is known to be associated with a high risk of VTE and, unfortunately, fixed doses of anticoagulant regimens may not provide optimal VTE prophylaxis in these patients especially after surgery.

Glucagon-like peptide 1 (GLP-1) is a hormone that helps regulate blood glucose levels through improved insulin sensitivity and release of insulin from the pancreas, control hunger, induce satiety and plays a role in the metabolic health of a person. GLP-1 receptor agonists (GLP1-RAs) have been shown to be effective in achieving weight loss in patients with type 2 diabetes while improving blood glucose control. Bariatric surgical procedures have been shown to be effective in treating obesity as well as superior to best medical therapy for treatment of diabetes not just through restriction of calories but also through a positive impact in modifications of gut hormones, changes in circulating bile acids, modifications in the gut microflora as well as other undefined mechanisms. The combined benefits of GLP1-RAs with bariatric surgery have only been studied to a limited effect. In this randomized trial, the effects of continuation or discontinuation of GLP1-RA therapy in patients undergoing bariatric surgery will be determined. We will compare changes in weight, metabolic determinants including circulating bile acids and gut microbiome, psychological determinants of eating behavior, and adverse side effects in patients who continue vs discontinue therapy. Given differences in metabolic and clinical outcomes in patients undergoing vertical sleeve gastrectomy (VSG) and Roux-en-Y gastric bypass (RYGB), both surgical groups will be examined. The study will be conducted at a high volume bariatric surgical program where patients will undergo randomization at the time of final clinic visit prior to surgery to continue or discontinue GLP1-RA. It is hypothesized that participants who continue GLP1-RA therapy after bariatric surgery will lose more weight with improved blood glucose control than those who discontinue therapy. Furthermore, changes in gut microbiome and circulating bile acids, known determinants of metabolic health, will be modified to a differential extent in those who are on GLP1-RAs vs those where GLP1-RAs are discontinued. Understanding the role these medications play in not only clinical outcomes after metabolic surgery but potential metabolic mechanisms by which surgery improves patient's metabolic health could help people with obesity and type 2 diabetes make informed decisions about their treatment options as well as advise providers on the continuation of these medications in the perioperative and postoperative period.

This study compares two surgical techniques used during one-anastomosis gastric bypass (OAGB) surgery for patients with severe obesity. During this operation, surgeons create a bypass of part of the small intestine, and the length of this bypassed segment (called the biliopancreatic limb) affects both weight loss and the risk of nutritional side effects. In this trial, one group of patients has the limb length calculated individually based on the measured total length of their small intestine (TSBL-based method), while the other group receives a limb length based on standard body mass index (BMI) categories (BMI-based method). The study compares weight loss outcomes, improvement of obesity-related health problems, and complication rates between the two approaches over 12 months after surgery. The trial is being conducted at a single center in Almaty, Kazakhstan, and plans to enroll 100 patients total; this record reflects an interim analysis based on the first 75 patients enrolled.

The goal of this randomized control trial is to compare different doses of Misoprostol (25 mcg vs 50 mcg) in induction of labor (IOL) in morbidly obese patients with BMI \>40. It is known that morbid obesity is a risk factor for failed IOL and ultimately cesarean delivery (CD.) If the rates of vaginal delivery in this population can improve, then surgical morbidity can be reduced in these patients.

Prospective observational cohort study evaluating the early proctologic effects of GLP-1 receptor agonist therapy in morbidly obese patients. Participants will undergo baseline and 3-month anorectal symptom assessment and proctologic examination to evaluate newly developed proctologic diseases and changes in pre-existing symptoms.

The goal of this observational study is to learn about how weight loss surgery (also called bariatric surgery) affects sexual function and sex hormone levels in women with severe obesity. It will also look at how the surgery affects mood, quality of life, body image, and the partner's sexual health. The main questions it aims to answer are: * Does sexual function improve after weight loss surgery? * Do sex hormone levels change after weight loss surgery? * Are these changes linked to improvements in mood and quality of life? * Does the partner also experience changes in sexual function? Researchers will compare each participant's results before surgery to their results 6 months after surgery. This helps show how things change over time. This study will include about 40 women who: * Are between 18 and 45 years old * Have severe obesity and are scheduled for weight loss surgery at Cairo University Hospital * Have a stable, sexually active partner relationship What participants will do: * Complete questionnaires about sexual function, mood, quality of life, and body image (twice: before surgery and 6 months after) * Provide a blood sample to measure sex hormone levels (before surgery and 6 months after) * Their partners will complete a short questionnaire about their own sexual function This research is important because sexual health is a key part of quality of life that is often overlooked in obesity care. Understanding how weight loss surgery affects sexual function, hormones, and mood can help doctors better counsel patients about what to expect after surgery. This is one of the first studies in Egypt to examine these questions and the first to include partner assessment. The study will start in January 2026. Results will be available by late 2026.

The aim of the study is to describe the effectiveness of Optilene® Silver Mesh Elastic on prevention of surgical site infection (SSI) at 6 months follow-up in patients undergoing urgent laparotomy by collecting clinical data on the SSI rates, IH rates and overall clinical performance of Optilene® Silver Mesh Elastic used for the prevention of incisional hernia as prophylactic mesh in patients that require urgent median laparotomy in clinical routine.

The management of obesity is based on a multidisciplinary approach and justifies the use of surgery in patients with the most severe forms. Surgery for obesity or bariatric surgery generally allows rapid and significant weight loss however it is associated with significant risks, and its long-term results remain heterogeneous and unpredictable. Long-term data will clarify the role of different types of bariatric surgery in surgical strategy, improve patient information and identify predictors of failure in order to provide personalised and tailored surgery for each candidate .

The aim of this study was to investigate the effects of whole body vibration on muscle functional level, physical fitness and respiratory parameters after bariatric surgery. Hypotheses of the study: H1: TVV after bariatric surgery has an effect on the functional level of the muscle. H2: TVV after bariatric surgery has an effect on physical fitness. H3: TVV after bariatric surgery has an effect on respiratory parameters. H4: TVV after bariatric surgery has an effect on quality of life. H5: TVV after bariatric surgery has an effect on body composition. H6: TVV after bariatric surgery has an effect on biochemical parameters. Patients will be divided into 3 randomized controlled groups. Whole body vibration application group, resistance exercise group and control group. The whole body vibration group will exercise on the device 3 days a week. Resistance exercise group will exercise with resistance band 3 days a week. All exercises will last 6 weeks. The whole body vibration, resistance exercise and control groups will be recommended to walk 7 days a week.

The goal of this observational study is to learn whether routine stool tests can detect changes in gut function 6 months after two common types of weight loss surgery: sleeve gastrectomy and gastric bypass (including mini gastric bypass and Roux-en-Y gastric bypass). The main questions it aims to answer are: Do stool tests show more signs of undigested food or carbohydrate malabsorption after gastric bypass compared to sleeve gastrectomy? Do signs of gut inflammation in stool (like fecal calprotectin) decrease after surgery, and does this relate to improvements in blood sugar and weight loss? Can simple stool test results at 6 months predict how much weight a person loses or how well their diabetes improves? Researchers will compare stool test results between the two surgery groups (sleeve gastrectomy vs. gastric bypass) to see if the type of surgery leads to different changes in gut health. Participants will: Provide a stool sample before surgery and again 6 months after surgery Provide a blood sample at the same time points to measure weight, blood sugar, and cholesterol Undergo their planned weight loss surgery as part of their regular medical care

Research the genetic and biomechanical markers of human adipose tissue on patients with morbid obesity. Additional tissue/fluid collection is also gathered during the time of surgery.

Patients with morbid obesity who require a breathing machine (mechanical ventilator) in the Intensive Care Unit (ICU) frequently experience partial lung collapse. This happens because the extra weight of the chest and abdomen presses on the lungs, reducing their capacity and making it difficult to maintain adequate oxygen levels. To address this, doctors often perform a standard lung recruitment maneuver, which involves temporarily increasing the air pressure from the ventilator to gently pop open the collapsed lung areas. However, standard bedside monitoring tools make it difficult to see exactly how well the different regions of the lungs are reopening. This prospective observational study aims to evaluate the use of Bedside Lung Ultrasound (LUS), which is a safe, radiation-free imaging tool, to monitor how well the lungs respond to these maneuvers in real-time. During the study, researchers will use a standardized 12-zone ultrasound scan to examine the lungs of mechanically ventilated adult patients (BMI ≥ 33 kg/m²) before, during, and after a step-by-step lung recruitment maneuver. By calculating a "Total Lung Ultrasound Score," the medical team can directly visualize and measure the transition from collapsed tissue to normal, aerated lung tissue. Furthermore, the ultrasound will be used during a step-down pressure phase to help identify the patient's "optimal PEEP" (Positive End-Expiratory Pressure), which is the exact customized pressure needed to keep the lungs open after the maneuver is complete, thereby improving oxygenation and minimizing the risk of lung injury.

The investigators propose a randomized controlled trial comparing BP and roux limb lengths measuring 30 and 15% respectively of patient's total small bowel length versus current standard practice using fixed lengths. The findings would provide further insight into feasibility of standardizing RYGB limb lengths and optimizing resultant weight loss and metabolic effects. The investigators hypothesize RYGB with ratio-adjusted limb lengths (aRYGB) will result in higher total weight loss and resolution of metabolic syndrome comorbidities, including diabetes, hyperlipidemia, and hypertension compared to standard fixed-length RYGB (sRYGB). The study will also utilize the Short Form Rand 36-Item Health Survey (SF36) to determine differences in postoperative quality of life metrics.

This observational study aims to learn about the correlation between the improving comorbidities associated with obesity after MGB (Mini-Gastric Bypass) surgery and changes in body composition in morbidly obese patients. The main questions it aims to answer are: To study the correlation between the improving comorbidities associated with obesity after MGB(Mini-Gastric Bypass) surgery and changes in body composition. Other objectives are: * Changes in the parameters of the metabolic syndrome after surgery * Changes in the cardiovascular risk biomarkers after metabolic surgery * Emergence in complications arising out of surgery requiring any intervention or causing a prolonged hospital stay, or requiring additional outpatient visits. Type of Study: An observational study in which participants with morbid obesity will undergo mini-gastric bypass surgery as per routine protocol. No separate experimental interventions will be done in the study for the participants.

This randomized controlled trial will evaluate the impact of chrono-nutrition, a dietary approach that aligns meal timing with the body's circadian rhythms, on weight change, metabolic outcomes, appetite, and gut microbiota in post-bariatric surgery patients. A total of 246 adults who underwent sleeve gastrectomy at least six months earlier will be enrolled at King Saud Medical City. Participants will be randomized to receive either standard post-bariatric nutritional care or personalized chrono-nutrition based on individual chronotype. Outcomes include weight change, metabolic biomarkers, dietary behaviors, sleep patterns, and gut microbiota composition. The study aims to determine whether integrating chrono-nutrition into post-bariatric follow-up can enhance metabolic health and improve long-term health.

Metabolic surgery is an emerging option to treat obesity-related metabolic diseases (e.g., type 2 diabetes) and prevent cardiovascular disease (CVD). Metabolic surgery can profoundly alter the gut microbiota; meanwhile, gut microbiota may affect surgical outcomes. Longitudinal studies that examined pre- to post-surgery changes in gut microbiota and its relation to cardiometabolic health after surgery are limited. Furthermore, few studies have included African Americans, a population with high rates of cardiometabolic diseases. The investigators aim to fill these research gaps by establishing a longitudinal, observational study of metabolic surgery patients and applying multi-omics to identify stool, blood, and/or tissue microbial features related to post-surgery cardiometabolic outcomes. In the current study, the investigators plan to enroll up to 300 patients who undergo metabolic surgery at Vanderbilt University Medical Center and follow them for up to 10 years after surgery. Fasting blood and stool samples will be collected at pre-surgery and 3-month, 1-year, 2-year, and 3-year post-surgery clinical visits. Tissue samples (e.g., biopsies of the liver and adipose and remnants of the stomach) will be collected during operation. Meanwhile, participants will complete a REDCap survey at baseline and 1-year, 2-year, and 3-year post-surgery. Participants' electronic medical records will be used to obtain additional information and facilitate long-term follow-up. The investigators will evaluate pre- to post-surgery changes in the fecal microbiome and fecal and blood levels of metabolites and proteins and the associations of microbiome, metabolites, and proteins with cardiometabolic improvements after surgery. This study will advance our understanding of the role of gut microbiota in metabolic surgery, which may translate into novel approaches to identify and treat obese patients for better cardiometabolic health.

Rapid onset Obesity, Hypoventilation, Hypothalamic dysfunction and Autonomic Dysregulation (ROHHAD) is a syndrome named in 2007. The hallmark of the syndrome is the rapid onset obesity and dysregulation of central ventilation. There is little information about the metabolic changes that lead to the rapid onset obesity in these children. The investigators would like to study the metabolic phenotype of these children to understand the disturbances in energy balance that lead to the rapid onset obesity.

The objective of this randomized controlled trial is to compare perioperative outcomes between laparoscopic and robotic approaches in patients with severe obesity who are candidates for RYGB. The trial aims to address the following key questions: To evaluate the difference between the two procedures in terms of postoperative complications. To assess intraoperative complications, conversion rate, mortality, operative times, postoperative hospital stay, and cost analysis for both approaches. In summary, the researchers will compare the laparoscopic and robotic approaches to determine which one leads to better perioperative outcomes

Postoperative nausea and vomiting (PONV) are the most common complications that can occur after general anesthesia. Postoperative use of opioids and morbid obesity have been reported as risk factors of PONV. In this study, the investigators aimed to compare the degree of postoperative side effects and pain control when an intravenous patient-controlled analgesia combining fentanyl and ketorolac via a dual-chamber device was provided to participants undergoing laparoscopic sleeve gastrectomy.

Obesity is a disease caused by many factors, such as lifestyle, eating habits, lack of physical activity, hormonal and genetic influences. These different factors make treatment planning difficult. Common treatments include changes in diet and lifestyle, medications, endoscopic methods (like balloon or botox), and surgery. No matter which method is used, the main goal is to help patients lose weight by creating a negative energy balance. To keep the weight off, patients need to maintain a balanced lifestyle in the long term. However, many treatments are not successful over time. One important part of long-term success is helping patients change their lifestyle and eating habits. A person's cognitive function may affect how they understand and follow these changes. Some studies show that a high body mass index (BMI) is linked to problems with thinking and memory. While weight loss may help improve brain function, the investigators don't yet know how early cognitive differences affect treatment results. At the obesity center in our hospital, morbidly obese patients receive support from a team of doctors, dietitians, psychologists, and physiotherapists. For at least three months, they attend individual and group sessions to help change their lifestyle and eating habits. This study aims to see how patients' cognitive function affects how much weight they lose by the end of the program.