Clinical Research Directory

Determinants of the Long-Term Success of Bariatric Surgery

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 .

Metabolic Responses to Bariatric Surgery

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.

Stool Analysis After Sleeve Gastrectomy vs Gastric Bypass

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

Activity Level Monitoring Study

The purpose of this study is to 1) evaluate the relationship of physical activity to quality of life and psychological functioning among adults with severe obesity (BMI\>40) and 2) evaluate the effects of activity monitoring on changes in physical activity during a 6-week intervention interval.

Bedside Lung Ultrasound to Monitor Lung Recruitment in Obese Patients

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.

Embolization of Arterial Gastric Supply in Obesity

This study aims to assess safety and efficacy of bariatric embolization of the gastro-epiploic arcade using 300-500 micrometres calibrated polyvinyl-alcohol microparticles, for patients with morbid obesity.

Ketodex Versus Opioid Based Anesthesia in Obese Patients Undergoing Laparoscopic Sleeve Gastrectomy.

comparing Opioid sparing anesthesia using ketodex versus opioid based anesthesia in obese patients undergoing laparoscopic sleeve gastrectomy.

Effect of Limb Length Ratio on Roux-en-Y Gastric Bypass Outcomes (CLIMB II Study)

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.

Impact of Bariatric Surgery on Female Sexual Function and Sex Hormones

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.

Comorbidities Resolution After MGB Surgery and Change in Body Composition

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.

Early Feasibility for Safety & Device Functionality of SFM Anastomosis Device Used in 3 Procedures (SNAP-S) or (SNAP-PS) or (J-J)

The objectives of this study are to assess the initial safety and device functionality of the SFM Anastomosis System including delivery systems when used to create a duodenal-ileal (D-I) anastomosis either during sleeve gastrectomy (i.e., SNAP-S procedure) or patients with prior sleeve gastrectomy who experience inadequate weight loss (i.e., SNAP-PS procedure) or a Roux-en-Y gastric bypass jejuno-jejunostomy. Additionally, the study is designed to evaluate the potential of these procedures to induce weight loss and to improve metabolic comorbidities in obese subjects.

Impact GLP-1 Agonists Following Bariatric

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.

Two Different Regimens of Bemiparin as a Thromboprophylaxis in Morbidly Obese Surgical Patients

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.

Chrono-ALIGN: A Chronotype-Based Chrono-Nutrition Intervention in Post-Bariatric Patients

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.

Tailored Stapled SADI-S: Initial Report and Preliminary Results

Obesity is a serious health problem worldwide and can lead to many diseases such as diabetes, high blood pressure, heart disease, and sleep apnea. When lifestyle changes and medications are not enough, metabolic and bariatric surgery (MBS) is currently the most effective and long-lasting treatment option. This study focuses on one of the newer types of bariatric surgery called Single Anastomosis Duodeno-Ileal Bypass with Sleeve Gastrectomy (SADI-S). This procedure combines two parts: Sleeve gastrectomy, which reduces the size of the stomach so the patient feels full after eating a small amount. Duodeno-ileal bypass, which shortens the path food takes through the small intestine to reduce calorie absorption. Our hospital's surgical team is studying a tailored version of this operation, where the length of the bypassed intestine is adjusted to each patient's anatomy. We believe this personalized approach may improve weight loss results while lowering the risk of vitamin and nutrient deficiencies. The study will include 40 adult patients with obesity who are undergoing SADI-S surgery, either as their first weight loss operation or as a revision surgery after an earlier sleeve gastrectomy. During the operation, surgeons will measure the total length of each patient's small intestine and use a formula to decide how much of it should be bypassed. The duodeno-ileal connection will be made using a stapled technique, which is expected to be safe and efficient. After surgery, patients will be followed regularly at 1, 3, 6, 9, and 12 months, and then once per year. At each visit, the study team will monitor weight loss, body mass index (BMI), resolution of diabetes and other obesity-related conditions, nutritional status (including vitamins and minerals), and any side effects such as diarrhea, reflux, or nutritional problems. The goal of this study is to learn whether this tailored SADI-S technique can provide strong, sustained weight loss and health improvement with fewer long-term complications. The results will help improve surgical planning for future patients by showing whether measuring and customizing the bypass length is safer and more effective than using a fixed length. All data collected will be kept confidential. Patients' participation in the study will not change their regular care or follow-up, and they can withdraw at any time without affecting their treatment.

Comparing Dumping Symptoms and Quality of Life 6 Months After Sleeve Gastrectomy With or Without Transit Bipartition in Adults With Obesity

This clinical study aims to compare two types of bariatric (weight loss) surgery used to treat obesity: sleeve gastrectomy alone and sleeve gastrectomy with transit bipartition. Both procedures help patients lose excess weight and improve obesity-related conditions such as diabetes and high blood pressure. However, they may differ in how they affect digestion and patients' quality of life after surgery. One possible complication after bariatric surgery is dumping syndrome. This occurs when food passes too quickly from the stomach into the small intestine, causing symptoms such as nausea, bloating, abdominal pain, diarrhea, dizziness, or fatigue after eating. These symptoms can be uncomfortable and may interfere with daily activities, eating habits, and overall well-being. The main goal of this study is to evaluate and compare both the occurrence of dumping syndrome and the overall quality of life six months after surgery in two groups of patients: Those who undergo sleeve gastrectomy alone. Those who undergo sleeve gastrectomy combined with transit bipartition. Participants will be adults with obesity who are scheduled to undergo bariatric surgery. Each participant will be evaluated before and after surgery using medical assessments and validated questionnaires that measure symptoms, eating patterns, and different aspects of quality of life-including physical health, emotional well-being, and social functioning. Follow-up visits and questionnaires will be conducted six months after surgery to determine how each surgical technique affects patients' digestion, comfort after meals, and overall satisfaction with their health and lifestyle. The study's hypothesis is that adding transit bipartition to sleeve gastrectomy may decrease the frequency or severity of dumping syndrome and lead to better quality of life outcomes compared to sleeve gastrectomy alone. By comparing these two surgical approaches, this study hopes to help surgeons and patients make better-informed decisions about bariatric surgery, aiming for the best combination of effective weight loss, minimal side effects, and improved long-term quality of life.

Gut Microbiota in Metabolic Surgery

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.

Whole Transcriptome Profiling and Metabolic Phenotyping in Children With ROHHAD Syndrome

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.

Long Term Effect of Very-low-calories Ketogenic Diet on Weight Control and Cardiovascular Brisk Factors (KETOHEART)

The growing obesity pandemic has a major impact on global cardiovascular (CVD)-related morbidity and premature mortality, severely compromising the quality of life of those affected and significantly increasing costs for the healthcare system. Numerous scientific evidences have demonstrated that a moderate weight loss (5-10% of the initial body weight) is already sufficient to determine the improvement of the cardiometabolic risk factors associated with overweight and obesity. With a view to obtaining a more significant weight loss in the initial stages of dietary treatment, in the last 10 years, the very low-calorie ketogenic diet (VLCKD) has become a strategy for the treatment of obesity and its comorbidities, also allowing to limit therapeutic failure and the high drop-out typical of traditional low-calorie diets. The present study aims to study the long-term efficacy (36 months) of VLCKD in patients with severe obesity and metabolic syndrome, on weight loss, on single factors of the metabolic syndrome compared to a restrictive Mediterranean diet. One hundred subjects with severe obesity and metabolic syndrome will be recruited and randomly assigned to VLCKD or to restrictive Mediterranean diet. Anthropometric parameters, metabolic status blood pressure, degree of arterial stiffness, prevalence and severity of snoring and OSA, cardiac systolic and diastolic function, the autonomic nervous control mode of the circulation will be evaluated at baseline, after one month and at the end of the study.

Effect of Laparoscopic Sleeve Gastrectomy Versus Roux-en-Y Gastric Bypass on Gastroesophageal Reflux Disease: An 8-Year Prospective Cohort Study

This study represents a long-term observational follow-up of patients who had previously undergone bariatric surgery (laparoscopic sleeve gastrectomy or Roux-en-Y gastric bypass) in the context of an earlier interventional trial (NCT03692455). No new interventions are assigned in the follow-up phase. Participants are evaluated clinically and functionally at predefined intervals using standardized multimodal assessments (symptom questionnaires, endoscopy, manometry, radiology, and pH monitoring).

Cost-Effectiveness and Outcome of Robot-assisted Vs Laparoscopic Roux-en-Y Gastric Bypass

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

Pilot Study on the Effectiveness and Safety of OPTILENE® SILVER MESH ELASTIC in Prevention of Surgical Site Infection (SSI) and Incisional Hernia (IH)

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.

Dual-chamber Patient-controlled Analgesia for Postoperative Recovery

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.

Induction of Labor in Morbidly Obese Patients

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.