One-year human experience with a novel endoluminal, endoscopic gastric bypass sleeve for morbid obesity

Bariatric and endo-bariatric interventions for diabetes: What is the current evidence?

Bariatric interventions have shown the best therapeutic benefits in individuals with obesity. They can be classified into surgical procedures (bariatric/metabolic surgery) and endoscopic procedures. Common surgical procedures include sleeve gastrectomy, Roux-en-Y gastric bypass, bilio-pancreatic diversion with or without duodenal switch and Stomach Intestinal Pylorus Sparing Surgery. Endoscopic procedures include intragastric balloons, transpyloric shuttle, endoscopic gastroplasties, aspiration therapy, duodenal mucosal resurfacing, duodeno-jejunal bypass liner, gastro-duodeno-jejunal bypass and incisionless magnetic anastomosis system among others. However, these procedures are limited by lack of wide availability, high costs, immediate and long-term complications and poor acceptability in some regions. Weight re-gain is a common concern and revisional metabolic surgery is often required. Appropriate pre-operative evaluation and correction of nutritional deficiencies post-surgery are very important. The most appropriate procedure for a person would depend on multiple factors like the intended magnitude of weight-loss, comorbidities and surgical fitness, as well as choice of the patient. Recently, glucagon-like insulinotropic peptide-1 receptor agonists (GLP) and the GLP-1/gastric inhibitory polypeptide co-agonist-Tirzepatide have shown remarkable weight loss potential, which is at par with bariatric interventions in some patients. How far these can help in avoiding invasive bariatric procedures in near future remains to be explored. An updated and comprehensive clinical review by He et al in the recent issue of World Journal of Diabetes address has addressed the avenues and challenges of currently available bariatric surgeries which will enable clinicians to make better decisions in their practice, including their applicability in special populations like the elderly and pediatric age groups, type 1 diabetes mellitus, and non-diabetics.

Endobariatric systems: Strategic integration of endoscopic therapies in the management of obesity

The escalating obesity pandemic and its comorbidities necessitate adaptable and versatile treatment strategies. Endobariatric and metabolic therapies (EBMTs) can be strategically employed in a multipronged approach to obesity management, analogous to the way chess systems are employed to seize opportunities and thwart threats. In this review, we explore the spectrum of established and developing EBMTs, examining their efficacy in weight loss and metabolic improvement and their importance for a tailored, patient-centric approach. The complexity of obesity management mirrors the intricate nature of a chess game, with an array of tactics and strategies available to address the opponent's moves. Similarly, the bariatric endoscopist employs a range of EBMTs to alter the gastrointestinal tract landscape, targeting critical anatomical regions to modify physiological reactions to food consumption and nutrient assimilation. Gastric-focused EBMTs aim to reduce stomach capacity and induce satiety. Intestinal-focused EBMTs target hormonal regulation and nutrient absorption to improve metabolic profiles. EBMTs offer unique advantages of reversibility, adjustability and minimal invasiveness, allowing them to be used as primary treatments, adjuncts to pharmacotherapy or tools to address post-bariatric surgery weight recidivism. However, sub-optimal adoption of EBMTs due to lack of awareness, perceived costs and limited training opportunities hinders their integration into standard obesity management practices. By strategically integrating EBMTs into the broader landscape of obesity care, leveraging their unique advantages to enhance outcomes, clinicians can offer a more dynamic and personalized treatment paradigm. This approach, akin to employing chess systems to adapt to evolving challenges, allows for a comprehensive, patient-centric management of obesity as a chronic, complex and relapsing disease.

Small Bowel Therapies for Metabolic Disease and Obesity

The small bowel has a crucial role in metabolic homeostasis. Small bowel endoscopic bariatric metabolic treatments (EBMTs) include several devices aimed at providing minimally invasive approaches for the management of metabolic disorders. The aim of this review is to provide an updated and exhaustive overview of the EBMTs targeting the small bowel developed to date, including the duodenal mucosa resurfacing, the duodenal-jejunal bypass liners, gastro-jejunal bypass sleeve, and the incisioneless magnetic anastomosis system, as well as to mention the future perspectives in the field.

Update on Endoscopic Treatments for Obesity

PURPOSE OF REVIEW

Increased morbidity seen with rising obesity rates continues to place an unheralded burden on our health system. Lack of higher bariatric surgery utilization and limitations with lifestyle modification and pharmacotherapy highlights the need for additional therapies for obesity. Endoscopic bariatric and metabolic therapies (EBMT) are effective, safe treatments for obesity. Current FDA-approved EBMT are confined to gastric modalities while small bowel directed therapies are still considered investigational. This review highlights current modalities of EBMT.

RECENT FINDINGS

Many randomized controlled trials have been performed, including both open label and sham-controlled, which have demonstrated safety and efficacy of EBMT over lifestyle therapy alone. In addition, emerging evidence from clinical experience further supports EBMT for treatment of obesity. Current evidence supports the safety and efficacy of EBMT for obesity treatment in conjunction with lifestyle therapy. They can also be used concurrently with weight loss medications to increase total weight loss.

Updates in metabolic bariatric endoscopy

Obesity and its associated comorbid conditions have been increasing globally. Endoscopic bariatric and metabolic therapies (EBMTs) were initially designed to replicate bariatric surgery physiology for those who are not or choose not to be surgical candidates. Now, newer procedures target the complicated pathophysiology underlying obesity and its comorbidities. EBMT has been categorized based on its therapeutic target (stomach or small intestine), but innovations have expanded to include extraintestinal organs including the pancreas. Gastric EBMTs, namely space-occupying balloons, gastroplasty with suturing or plication, and aspiration therapy, are primarily used for weight loss. Small bowel EBMTs are designed to cause malabsorption, epithelial endocrine remodeling, and other changes to intestinal physiology to ultimately improve the metabolic comorbidities of obesity rather than induce weight loss alone. These include duodenal mucosal resurfacing, endoluminal bypass sleeves, and incisionless anastomosis systems. Extraluminal or pancreatic EBMT is aimed to restore the production of normal pancreatic proteins that are involved in the progression of type 2 diabetes. This review discusses the current and new technologies of metabolic bariatric endoscopy, their pros and cons, and areas for future research.

Emerging Endoscopic Interventions in Bariatric Surgery

Various endoscopic tools and techniques have been developed to treat obesity and its associated weight-related medical conditions. However, many of these endoscopic treatments may be little known or utilized. This article examines the many endoscopic options that have been developed to treat obesity including gastric aspiration devices, incisionless magnetic anastomotic systems, endoluminal bypass barrier sleeves, primary obesity surgery endoluminal, endoscopic sleeve gastroplasty, and duodenal mucosal resurfacing. We review their development, application, efficacy, and the reported literature on their use and results.

Overview on the endoscopic treatment for obesity: A review

Obesity rates have increased, and so has the need for more specific treatments. This trend has raised interest in non-surgical weight loss techniques that are novel, safe, and straightforward. Thus, the present review describes the endoscopic bariatric treatment for obesity, its most recent supporting data, the questions it raises, and its future directions. Various endoscopic bariatric therapies for weight reduction, such as intragastric balloons (IGBs), aspiration therapy (AT), small bowel endoscopy, endoscopic sleeve gastroplasty, endoluminal procedures, malabsorption endoscopic procedures, and methods of regulating gastric emptying, were explored through literature sourced from different databases. IGBs, AT, and small bowel endoscopy have short-term effects with a possibility of weight regain. Minor adverse events have occurred; however, all procedures reduce weight. Vomiting and nausea are common side effects, although serious complications have also been observed.

Small intestine-targeted endoscopic bariatrics: Current status and future perspectives

The global obesity epidemic shows no signs of slowing down. Endoscopic bariatric and metabolic therapies (EBMTs) are being increasingly adopted as treatment options for obesity and obesity-related comorbidities, due to their minimally invasive nature and ease of delivery. According to the site of action along the gastrointestinal tract, EBMTs can be divided into two categories: gastric EBMTs, and small intestine-targeted EBMTs. Unlike gastric EBMTs, which work through a volume-restricting mechanism leading to early satiety and reduced caloric intake, small intestine-targeted EBMTs can be metabolically beneficial through foregut and/or hindgut pathways independent of weight loss, and therefore have great potential for the treatment of obesity-related metabolic comorbidities such as type 2 diabetes. Although none of the small intestine-targeted EBMTs have been approved by the US Food and Drug Administration to date, their clinical efficacy and safety have been extensively explored in investigational trials. This review aims to summarize and provide a comprehensive understanding of small intestine-targeted EBMTs in clinical and preclinical settings, and to further discuss their potential mechanisms of action.

Advances in endobariatrics: past, present, and future

The obesity epidemic in the USA and worldwide is well documented and continues to grow. Endoscopic metabolic and bariatric therapies may offer a less invasive approach than surgical intervention. This article will review advances in endobariatrics over the last several decades, addressing the past and current state of bariatric and metabolic endoscopy. Food and Drug Administration-cleared devices and interventions currently under investigation are described including gastric devices, gastric remodeling procedures, small-bowel devices, duodenal ablation, as well as procedures to address weight regain after bariatric surgery. Future studies evaluating gastric and duodenal combination therapy, adjunctive pharmacotherapy, as well as individualized precision-health algorithms are underway.

A Comprehensive Review on Bariatric Endoscopy: Where We Are Now and Where We Are Going

Background: Obesity is a chronic disease that impairs quality of life and leads to several comorbidities. When conservative therapies fail, bariatric surgical options such as Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG) are the most effective therapies to induce persistent weight loss. Over the last two decades, bariatric endoscopy has become a valid alternative to surgery in specific settings. Primary bariatric endoscopic therapies: Restrictive gastric procedures, such as intragastric balloons (IGBs) and endoscopic gastroplasty, have been shown to be effective in inducing weight loss compared to diet modifications alone. Endoscopic gastroplasty is usually superior to IGBs in maintaining weight loss in the long-term period, whereas IGBs have an established role as a bridge-to-surgery approach in severely obese patients. IGBs in a minority of patients could be poorly tolerated and require early removal. More recently, novel endoscopic systems have been developed with the combined purpose of inducing weight loss and improving metabolic conditions. Duodenal mucosal resurfacing demonstrated efficacy in this field in its early trials: significant reduction from baseline of HbA1c values and a modest reduction of body weight were observed. Other endoscopic malabsorptive have been developed but need more evidence. For example, a pivotal trial on duodenojejunal bypasses was stopped due to the high rate of severe adverse events (hepatic abscesses). Optimization of these more recent malabsorptive endoscopic procedures could expand the plethora of bariatric patients that could be treated with the intention of improving their metabolic conditions. Revisional bariatric therapies: Weight regain may occur in up to one third of patients after bariatric surgery. Different endoscopic procedures are currently performed after both RYGB and SG in order to modulate post-surgical anatomy. The application of argon plasma coagulation associated with endoscopic full-thickness suturing systems (APC-TORe) and Re-EndoSleeve have shown to be the most effective endoscopic treatments after RYGB and SG, respectively. Both procedures are usually well tolerated and have a very low risk of stricture. However, APC-TORe may sometimes require more than one session to obtain adequate final results. The aim of this review is to explore all the currently available primary and revisional endoscopic bariatric therapies focusing on their efficacy and safety and their potential application in clinical practice.

Physiology Reconfigured: How Does Bariatric Surgery Lead to Diabetes Remission?

Bariatric surgery improves glucose homeostasis and glycemic control in patients with type 2 diabetes. Over the past 20 years, a breadth of studies has been conducted in humans and rodents aimed to identify the regulatory nodes responsible for surgical remission of type 2 diabetes. The review herein discusses central mechanisms of type 2 diabetes remission associated with weight loss and surgical modification of the gastrointestinal tract.

Endoscopic bariatrics: current therapies and future directions

Endoscopic bariatric therapies (EBTs) are endoscopic procedures indicated for weight loss in the obese population. They are shown to be safe and effective for patients who do not quality for bariatric surgery. There are currently no randomized controlled studies comparing bariatric surgery with EBTs. However, EBTs are more cost effective and have fewer complications. This review will examine currently available EBTs with published data.

Endoscopic Treatment of Obesity and Nutritional Aspects of Bariatric Endoscopy

Obesity is a significant problem worldwide. Several serious diseases that decrease patient quality of life and increase mortality (high blood pressure, dyslipidaemia, type 2 diabetes etc.) are associated with obesity. Obesity treatment is a multidisciplinary and complex process that requires maximum patient compliance. Change of lifestyle is fundamental in the treatment of obesity. While pharmacotherapeutic options are available, their efficacy is limited. Surgical treatment though highly effective, carries the risk of complications and is thus indicated mostly in advanced stages of obesity. Endoscopic treatments of obesity are less invasive than surgical options, and are associated with fewer complications and nutritional deficits. Currently, there is a large spectrum of endoscopic methods based on the principles of gastric volume reduction, size restriction and gastric or small bowel bypass being explored with only few available in routine practice. The aim of this publication is to present an up-to-date summary of available endoscopic methods for the treatment of obesity focusing on their efficacy, safety and nutritional aspects.

Endoscopic Approaches to Obesity Management

The field of endoscopic bariatric and metabolic therapy has rapidly evolved from offering endoscopic treatment of weight regain following bariatric surgery to providing primary weight loss options as alternatives to pharmacologic and surgical interventions. Gastric devices and remodeling procedures were initially designed to work through a mechanism of volume restriction, leading to earlier satiety and reduced caloric intake. As the field continues to grow, small bowel interventions are evolving that may have some effect on weight loss but focus on the treatment of obesity-related comorbidities. Future implementation of combination therapy that utilizes both gastric and small bowel interventions offers an exciting option to further augment weight loss and alleviate metabolic disease. This review considers gastric devices and techniques including space-occupying intragastric balloons, aspiration therapy, endoscopic tissue suturing, and plication interventions, followed by a review of small bowel interventions including endoluminal bypass liners, duodenal mucosal resurfacing, and endoscopically delivered devices to create incisionless anastomoses. Expected final online publication date for the Annual Review of Medicine, Volume 73 is January 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Bariatric and Metabolic Endoscopy: A New Paradigm

The prevalence of obesity, type 2 diabetes mellitus, and metabolic syndromes is increasing globally. Minimally invasive metabobariatric (MB) endoscopic therapies are adjunct treatments that can potentially bridge the gap between surgical interventions and medical therapy. A growing number of MB techniques are becoming available, allowing for more personalized and patient-targeted treatment options for specific disease states. MB techniques are less invasive than surgery and can precisely target different parts of the gastrointestinal tract that may be responsible for the pathophysiology of obesity and metabolic syndromes such as type 2 diabetes mellitus. These alternatives should be selected on an individualized patient basis to balance the expected clinical outcomes and desired anatomical targets with the level of invasiveness and degree of acceptable risk. Each MB intervention presents great flexibility allowing for a tailored intervention and different levels of patient engagement. Patient awareness and motivation are essential to avoid therapy withdrawal and failure. Differences between MB procedures in terms of weight loss and metabolic benefit will be discussed in this review, along with the insights on clinical decision-making processes to evaluate the potential of further evolution and growth of bariatric and metabolic endoscopy.

Emerging Endoscopic Interventions in Bariatric Surgery

Although obesity rates are growing across the world, endoscopic modalities to treat obesity and its metabolic consequences are advancing rapidly. Multiple devices and techniques dedicated to weight management are being developed and have either been approved for use or are undergoing clinical trial. This article reviews many of these endoscopic interventions in bariatric surgery, including gastric aspiration devices, incisionless magnetic anastomotic systems, endoluminal bypass barrier sleeves, primary surgery obesity endoluminal, endoscopic sleeve gastroplasty, and duodenal mucosal resurfacing. These effective techniques may serve either as a primary therapy or as a bridge to bariatric surgery.

The current state of bariatric endoscopy

A variety of endoscopic bariatric and metabolic treatments (EBMTs) have been developed in recent years to combat the growing prevalence of obesity in the United States (US) and worldwide. This manuscript reviews the current state of bariatric endoscopy, detailing all US Food and Drug Administration (FDA) approved EBMTs including space-occupying intragastric balloons (IGBs), aspiration therapy, and endoscopic tissue apposition devices. Additionally, this review describes non-FDA approved treatments including additional IGBs, endoluminal bypass liners, duodenal mucosal resurfacing, and endoscopically placed anastomosis devices.

Various Novel and Emerging Technologies in Endoscopic Bariatric and Metabolic Treatments

Obesity, along with its comorbidities, has become a significant public health concern worldwide. Bariatric surgery is considered the most effective treatment modality; however, only 2% of patients with obesity undergo bariatric surgery. Endoscopic bariatric and metabolic therapies (EBMTs) are emerging alternatives to traditional bariatric surgery for patients who are not eligible for or do not prefer surgical treatment. EBMTs are generally categorized as space-occupying, gastric restrictive, aspiration, and small bowel therapies. We aimed to review various non-balloon and non-gastroplasty devices with available clinical data and discuss the possible mechanisms of action, efficacy, and safety profile of these EMBTs.

Endobariatric procedures for obesity: clinical indications and available options

Obesity remains a growing public health epidemic that has increased healthcare costs and related comorbidities. Current treatment guidelines encourage a multidisciplinary approach starting from patient selection, interventions, and long-term follow-up to maintain weight loss. However, these conservative interventions are largely ineffective at reducing body weight due to low adherence to the treatment regimen. Recently, endoscopic bariatric therapies have become an attractive alternative to traditional invasive bariatric surgeries due to their improved efficacy, safety, and cost-effectiveness. Endoscopic bariatric therapies include intragastric balloon placement, endoscopic sleeve gastroplasty, gastric bypass revision, and aspiration therapy. These procedures fall into two separate categories depending on the primary mechanism involved: restrictive or malabsorptive. Restrictive methods, such as the Orbera® and ReShape™ intragastric balloons, increase satiation and delay gastric emptying while decreasing the amount of food that can be ingested. In contrast, malabsorptive devices, such as the EndoBarrier®, interfere with the small intestine's ability to absorb food while restoring normal gastrointestinal hormone levels regulating satiation. Together, these techniques provide useful alternatives for patients in whom pharmacological or lifestyle modifications have proven ineffective. Despite these advantages, the long-term effects of these procedures on metabolic changes remain to be studied. Furthermore, the management of complications from these procedures continues to evolve. In this review, we aim to elaborate on the clinical indications and efficacy of the endobariatric procedures, together with various types of available endoscopic bariatric therapy procedures.

Endobariatrics and Metabolic Endoscopy: Can We Solve the Obesity Epidemic with Our Scope?

PURPOSE OF REVIEW

Obesity is a chronic relapsing disease that results in cardiovascular disease, diabetes mellitus, and non-alcoholic fatty liver disease. Currently, surgery represents the most effective treatment. However, the advent of minimally invasive endoscopic bariatric therapy (EBT) has shifted the treatment paradigm to less invasive, cost-effective procedures with minimal complications and recovery time that are preferred by patients. In this review, we will describe current and future EBTs, focusing on outcomes and safety.

RECENT FINDINGS

The endoscope has provided an incisionless portal into the gastrointestinal tract for placement of space-occupying devices and intraluminal procedures. EBTs are no longer solely manipulating anatomic alterations; instead, they aim to improve metabolic parameters such as glycated hemoglobin, low-density lipoprotein, cholesterol, and hepatic indices by targeting the mucosal layer of the gastrointestinal tract. The endoscope has succeeded in facilitating clinically meaningful weight loss and improvement of metabolic parameters. Future, solutions to the obesity epidemic will likely entail genetic testing, evaluation of the microbiome, and delivery of personalized therapy, utilizing combination endoscopic modalities that change the anatomy and physiology of individual patients, with new targets such as the abnormal metabolic signal.

Bariatric endoscopy: current primary therapies and endoscopic management of complications and other related conditions

The steady increase in bariatric surgery has led to room for innovation. Endoscopy has become an important tool for evaluation, diagnosis, management of complications, and even for primary bariatric interventions. Leaks are the most feared complication and new endoscopic therapies have been developed such as septotomy, double-pigtail stents, and endoscopic vacuum therapy. Additionally, primary bariatric endoscopic procedures are gaining popularity and the new procedures include intragastric balloons, stoma reduction, aspiration therapy, among others. The altered anatomy and reoperation increase the risk of complications after bariatric surgery, especially when managing conditions like achalasia, gastroparesis, and cholelithiasis. Per-oral endoscopic myotomy, per-oral pyloromyotomy, and endoscopic ultrasound-guided transgastric endoscopic retrograde cholangiopancreatography provide a less invasive approach to address these conditions. This narrative review article intends to expose current endoscopic therapies for the management of primary bariatric procedures, complications and related conditions.

Metabolic endoscopy: Today's science-tomorrow's treatment

Obesity, type 2 diabetes mellitus (T2DM) and nonalcoholic steatohepatitis are increasing pandemic metabolic disorders. Lifestyle intervention (LSI) is the cornerstone treatment for these but is successful as standard care alone in only a few patients, given the modest weight loss at mid and long term. Conversely, bariatric surgery is the only proven effective treatment for these metabolic disorders, albeit offered only in a small percentage of cases because of its invasiveness and cost. The so-called endoscopic bariatric and metabolic therapies (EBMTs) include new, less-invasive technologies such as intragastric balloons, aspiration therapy, endoscopic sleeve gastroplasty, diversion devices, and duodenal mucosal resurfacing, currently at various stages of development. EBMTs, as an add-on to LSI, might represent an effective treatment filling the gap between medical and surgical management, taking into account, however, that obesity and its associated comorbidities constitute a chronic disease that needs lifelong therapy. In this review we describe the current scientific evidence surrounding EBMTs as well as future opportunities for such treatments in managing obesity and metabolic disorders.

Bariatric and Metabolic Therapies Targeting the Small Intestine

The global prevalence of obesity and type 2 diabetes (T2DM) necessitates an increased reliance on effective and safe endoscopic therapies. While surgery is highly effective, endoscopic therapies may be able to reach a greater number of affected individuals and help to reduce the burden of disease worldwide. Although current endoscopic treatments entail space occupying gastric devices as well as suturing or plication, innovative, non-Food and Drug Administration (FDA) approved small bowel specific endoscopic bariatric and metabolic therapies have been developed within the last several years. Small intestine therapies include endoluminal bypass liners, duodenal mucosal resurfacing, endoscopic anastomosis systems, and restricted duodenal flow treatments. These endoscopic bariatric and metabolic therapies rely upon foregut and hindgut mechanisms to achieve weight loss and improve glucose homeostasis. This review will detail these important small bowel mechanisms and evaluates current small bowel endoscopic treatments.

Procedures and devices for bariatric and metabolic endoscopy

Obesity is a leading cause of preventable death in developed countries, with a rising incidence over time. Lifestyle modification, pharmacotherapy, and bariatric surgery are the mainstays of bariatric therapy, even though burdened by several limitations in terms of efficacy or safety. Bariatric endoscopy has been developed in the last decades as a minimally invasive alternative, aimed to bridge the gap between conservative and interventional conventional therapies. This review aims to provide an updated overview of the bariatric and metabolic available endoscopic procedures and to drive the choice of the right procedure for the right patient.

Endoscopic Treatments for Obesity: The Good, the Bad, and the Ugly

In the current setting of an obesity pandemic, there is an urgent need for minimally invasive, safe, and effective interventions for weight loss. Endoscopic bariatric procedures have been developed as an alternative to more traditional medical and surgical therapies. Multiple options are undergoing evaluation or are already available for clinical use. This review aims to describe these treatments, including their mechanisms of action, efficacy, safety and the knowledge gaps regarding their use.

Metabolic endoscopy by duodenal mucosal resurfacing: expert review with critical appraisal of the current technique and results

INTRODUCTION

Duodenal mucosal resurfacing (DMR) is an endoscopic procedure for type 2 diabetes (T2D) consisting of circumferential hydrothermal ablation of the duodenal mucosa.

AREAS COVERED

A review was conducted on the reports available up to March-2020. On a total of 79 patients, DMR induced a significant mean HbA1c, FPG and HOMA-IR reduction at 6 months (0.9 ± 0.2%, 1.7 ± 0.5 mmol/L and 2.9 ± 1.1 mUI/L respectively - P < 0.001). DMR metabolic efficacy directly correlates with the length of the ablated mucosa (mean 3 months HbA1c reduction 1.2% vs 2.5% after short and long ablation respectively - P < 0.05), while it is independent of weight-loss. Severe AEs were registered in 3.7% of the cases.

EXPERT OPINION

DMR plays a promising role in metabolic impairment improvement inducing a morpho-functional duodenal alteration not necessarily depending on weight-loss. Technical-functional improvements of the device and appropriate training aimed at its correct use are needed to lower the rate of severe AEs and technical failure. The current role of DMR needs to be clarified, but it might be proposed for poorly controlled T2D in accurately selected patients. Evidence on DMR is still scanty and further research is mandatory to standardize the endoscopic technique and its indications.

Current and Future Endoscopic Weight Loss Solutions

Obesity poses a significant health care concern in the United States, with 39.8% of adults being classified as obese. Several different methods have been introduced to combat obesity, from medical therapy to surgical options. Bariatric surgery has been demonstrated to be superior to medical therapy alone for weight loss in obese patients. Despite this information, only about 1% of eligible patients undergo bariatric surgery per year. The reason for this treatment gap is multifactorial, but patient apprehension to undergo surgery is a major driving force. Many patients perceive bariatric surgery as dangerous, and believe that living with their current weight is safer than undergoing surgery. To combat this treatment gap, endoscopic therapies have been developed to reach more patients in a less invasive way. This article will review endoscopic treatment options currently available and approved by the Food and Drug Administration, as well as other treatment modalities that are currently in development.

Novel and emerging devices and operations in the treatment of obesity in children and adolescents

Obesity is among the most common and costly chronic disorders worldwide. Estimates suggest that in the United States obesity affects one-third of adults, accounts for up to one-third of total mortality, is concentrated among lower income groups, and increasingly affects children as well as adults. A lack of effective options for long-term weight reduction magnifies the enormity of this problem; individuals who successfully complete behavioral and dietary weight-loss programs eventually regain most of the lost weight. We included evidence from basic science, clinical, and epidemiological literature to assess current knowledge regarding mechanisms underlying excess body-fat accumulation, the biological defense of excess fat mass, and the tendency for lost weight to be regained. A major area of emphasis is the science of energy homeostasis, the biological process that maintains weight stability by actively matching energy intake to energy expenditure over time. Growing evidence suggests that obesity is a disorder of the energy homeostasis system, rather than simply arising from the passive accumulation of excess weight. We need to elucidate the mechanisms underlying this "upward setting" or "resetting" of the defended level of body-fat mass, whether inherited or acquired. The ongoing study of how genetic, developmental, and environmental forces affect the energy homeostasis system will help us better understand these mechanisms and are therefore a major focus of this statement. The scientific goal is to elucidate obesity pathogenesis so as to better inform treatment, public policy, advocacy, and awareness of obesity in ways that ultimately diminish its public health and economic consequences.

Endoscopic bariatric and metabolic therapies: Another tool for the management of diabetes and obesity

Endoscopic bariatric and metabolic therapies (EBMTs) have sparked significant interest as minimally invasive therapeutic options for weight loss. Although bariatric surgery remains an effective option for sustained weight loss and improvement in the metabolic syndrome, access and utilization are limited. Various EBMTs have been designed to emulate the physiologic effects of established surgical interventions, including space-occupying and non-space-occupying gastric therapies, gastric remodeling procedures, and small bowel therapies. This review discusses the safety and efficacy of available US Food and Drug Administration-approved minimally invasive endoscopic bariatric interventions, as well as those currently under investigation. In addition, the role of endoscopic revision after failed surgical intervention is discussed.

Development of Bariatric and Metabolic Endoscopy

Objective:

With the evolution of society and changes in human lifestyle, obesity is becoming increasingly prevalent worldwide, and obesity-related comorbidities such as diabetes, hyperlipidemia, hypertension, and coronary heart disease are more common. As a result, new devices and methods for bariatric and metabolic endoscopy are being developed for clinical use, offering new options for patients. This review discussed the progress in bariatric and metabolic endoscopy.

Data Sources:

This review was based on data in articles published in the PubMed database up to September 2017, with the following keywords: “obesity”, “endoscopy”, “weight loss”, and “metabolism”.

Study Selection:

Original articles about various endoscopic methods of weight loss and other reviews of bariatric and metabolic endoscopy were included and analyzed.

Results:

The technology of bariatric and metabolic endoscopy has advanced rapidly in recent years. The intragastric balloon (IGB), with its comparatively long period of development, is the most mature and widely used instrument. Multiple new endoscopic devices have been created in recent years, with different targets to achieve weight loss. Despite the proliferation of new devices, the lack of clinical data results in a shortage of clinical experience and instruction in the use of this new equipment.

Conclusions:

Bariatric and metabolic endoscopy would help obese people lose weight or prepare for bariatric surgery and hopefully alleviate some of the complications of bariatric procedures. Adequate studies and data are still needed for the new endoscopic devices.

Role of Bile Acids and GLP-1 in Mediating the Metabolic Improvements of Bariatric Surgery

BACKGROUND & AIMS

Bile diversion to the ileum (GB-IL) has strikingly similar metabolic and satiating effects to Roux-en-Y gastric bypass (RYGB) in rodent obesity models. The metabolic benefits of these procedures are thought to be mediated by increased bile acids, although parallel changes in body weight and other confounding variables limit this interpretation.

METHODS

Global G protein-coupled bile acid receptor-1 null (Tgr5^-/-) and intestinal-specific farnesoid X receptor null (Fxr^Δ/E) mice on high-fat diet as well as wild-type C57BL/6 and glucagon-like polypeptide 1 receptor deficient (Glp-1r^-/-) mice on chow diet were characterized following GB-IL.

RESULTS

GB-IL induced weight loss and improved oral glucose tolerance in Tgr5^-/-, but not Fxr^Δ/E mice fed a high-fat diet, suggesting a role for intestinal Fxr. GB-IL in wild-type, chow-fed mice prompted weight-independent improvements in glycemia and glucose tolerance secondary to augmented insulin responsiveness. Improvements were concomitant with increased levels of lymphatic GLP-1 in the fasted state and increased levels of intestinal Akkermansia muciniphila. Improvements in fasting glycemia after GB-IL were mitigated with exendin-9, a GLP-1 receptor antagonist, or cholestyramine, a bile acid sequestrant. The glucoregulatory effects of GB-IL were lost in whole-body Glp-1r^-/- mice.

CONCLUSIONS

Bile diversion to the ileum improves glucose homeostasis via an intestinal Fxr-Glp-1 axis. Altered intestinal bile acid availability, independent of weight loss, and intestinal Akkermansia muciniphila appear to mediate the metabolic changes observed after bariatric surgery and might be manipulated for treatment of obesity and diabetes.

Spanish consensus document on bariatric endoscopy. Part 2: specific endoscopic treatments

During the last years we have been witnessing a significant increase in the number and type of bariatric endoscopic techniques: we have different types of balloons, suture systems, injection of substances and malabsorptive prosthesis, etc. Also, some endoscopic revisional procedures for patients with weight regain after bariatric surgery have been incorporated. This makes it necessary to protocolize, position and regularize all these techniques, through a consensus that allows their clinical application with the maximum medical rigor and scientific evidence available.

Small Bowel Endoscopic Bariatric Therapies

Endoscopic bariatric therapies that emulate some of the principles of bariatric surgery have been developed as a less invasive option for the treatment of obesity and related comorbidities. Small bowel endoscopic bariatric therapies include bypass sleeves, incisionless anastomosis systems, and duodenal mucosal resurfacing. Clinical experience with small bowel devices suggests that endoscopic bariatric procedures can be safely implemented and that these devices are effective for both weight loss and metabolic improvement. Although the mechanisms behind these effects should be further elucidated, endoscopic bariatric therapies may be more effective and safer adjunctive interventions than lifestyle modifications and pharmacological regimens for patients with obesity or obesity-related comorbidities.

Endoscopic Interventions in the Treatment of Obesity and Diabetes

Obesity is a global health problem which is on the rise and is strongly associated with the development of type 2 diabetes and other comorbidities. Bariatric surgery is now an established treatment for both these conditions, leading to impressive results in weight loss and glycemic control. More recently, we have seen the development of various endoscopic devices as potential alternatives or adjuncts to bariatric surgery. In this state-of-the-art review, we outline the current landscape of endoscopic treatments available for the management of both obesity and diabetes, including the clinical evidence supporting their use, efficacy, safety, and potential mechanisms of action.

Devices and Endoscopic Bariatric Therapies for Obesity

PURPOSE OF REVIEW

In this review, we describe the FDA-approved and investigational devices and endoscopic bariatric therapies for the treatment of obesity. We focus on literature published in the past few years and present mechanisms of action as well as efficacy and safety data.

RECENT FINDINGS

Devices and endoscopic procedures are emerging options to fill the significant treatment gap in the management of obesity. Not only are these devices and procedures minimally invasive and reversible, but they are potentially more effective than antiobesity medications, often safer for poor surgical candidates and possibly less expensive than bariatric surgery. As many patients require a variety of management strategies (medications, devices, procedures, and/or surgery) in addition to lifestyle modifications to achieve clinically significant weight loss, the future of obesity treatment involves a multidisciplinary approach. Combinations of advanced treatment strategies can lead to additive or synergistic weight loss. This is an area that requires further investigation.

SAGES review of endoscopic and minimally invasive bariatric interventions: a review of endoscopic and non-surgical bariatric interventions

BACKGROUND

With obesity continuing as a global epidemic and therapeutic technologies advancing, several novel endoscopic and minimally invasive interventions will likely become available as treatment options. With improved technologies and different treatment strategies, as well as different patient populations being targeted, there will be greater application in the treatment armamentarium of specialists dedicated to treating obesity. We sought to review the existing technology and provide a review.

METHODS

Literature review was carried out for endoscopic and minimally invasive devices. Some of these products are not FDA approved, so limited data are available in their review.

RESULTS

A summary of the device and data currently available on weight loss and safety profile is provided. Several products are in clinical trials or will be soon. Some of the technology has limited data and companies will be submitting their results for FDA evaluation.

CONCLUSIONS

The obesity epidemic and associated weight-related diseases represent a tremendous burden to health care practitioners. As such, a multi-modal and progressive approach, with data and outcomes examined, is likely the best and most comprehensive method to care for these patients. SAGES endorses the benefits of minimally invasive and endoscopic approaches in the treatment of obesity and its related co-morbidities.

Totally endoscopic implant to effect a gastric bypass: 12-month safety and efficacy outcomes

BACKGROUND

Only a small percentage of candidates for bariatric surgery ever undergo a procedure for weight loss. Devices duplicating key effects of bariatric surgeries with removable, fully trans-oral implants could extend their benefits to patients unwilling to undergo anatomy-altering abdominal surgeries.

METHODS

Thirty-two obese subjects (mean BMI: 42.3) were enrolled in a prospective, multicenter, single-arm, feasibility trial of the first fully trans-oral endoscopic gastrointestinal bypass device. The device is a cuff attached to the distal esophagus by transmural anchors and connected to a 120-cm sleeve diverting undigested nutrients to the jejunum. Bodyweight, vital signs, adverse events, medications, HbA1c, fasting glucose, and lipids were collected at baseline and follow-up visits. Device status was endoscopically assessed every 6 months.

RESULTS

The fully trans-oral procedure was successful in all subjects without intraoperative adverse events or postoperative infections. Twenty-eight of 32 subjects (88%) remained implanted with continuing follow-up beyond their 12-month visit. At 12 months, the 32 subjects had lost an average of 44.8% of excess body weight, 17.6% of total body weight, 20.8 kg, and 7.5 BMI points. Weight loss depended on capture of ingesta by the esophageal cuff, with 18 of 32 subjects without visible gaps around their cuffs at the 6 month endoscopy having significantly greater EWL (53.6 vs. 33.4% in the remaining subjects, p < 0.002). Mean HbA1c and fasting glucose declined by 1.1% points and 29 mg/dL in type 2 diabetic subjects, 80% of whom had remission of their diabetes at 12 months.

CONCLUSION

This study demonstrates the feasibility, safety, and efficacy of a fully trans-oral gastrointestinal bypass implant. This purely endoscopic device may provide a valuable addition to the armamentarium of treatment available for the management of morbid obesity.

Medical Devices for Obesity Treatment: Endoscopic Bariatric Therapies

Endoscopic bariatric therapies (EBTs) are effective tools for the management of obesity. By mimicking restrictive and bypass surgery physiology, they provide a safe and effective treatment option with the added capabilities of reaching a broader population. Multiple efficacious medical devices, such as intragastric balloons, endoscopic suturing/plication devices, and bypass liners, at various stages of development are available in the United States. EBTs represent the newest addition to a multidisciplinary approach in obesity management. This article reviews several devices' safety and efficacy for primary care providers in the era of evolving obesity treatment.

Endoscopic Medical Devices for Primary Obesity Treatment in Patients With Diabetes

IN BRIEF Several new endoscopic bariatric therapies have been approved by the U.S. Food and Drug Administration for the treatment of obesity, with many more devices and procedures undergoing investigational studies. This article describes these devices and procedures and special considerations for their use in patients with diabetes.

Endoscopic Treatments for Obesity

Purpose of review Endoscopic bariatric therapy (EBT) is a rapidly developing area that has now seen FDA approval of six endoscopic bariatric devices and procedures and there are a number of other novel EBTs progressing through various stages of development with newly published findings. This paper aims to assist readers in either selecting an appropriate therapy for their patient or deciding to incorporate these therapies into their practice. This paper provides an updated review of the available data on EBTs, both FDA approved and not, with a particular focus on effectiveness and safety, as well as guidance for discussing with your patient the decision to use endoscopic therapies. Findings The authors of a large meta-analysis of Orbera concluded its ideal balloon volume to be 600-650 mL. AspireAssist has had favorable effectiveness and safety data published in a large RCT. A large study of endoscopic sleeve gastroplasty has published findings at up to 24 months showing promising durability. Elipse, a swallowed intragastric balloon not requiring endoscopy for either insertion or removal, has had early favorable results published. A magnet-based system for creation of a gastrojejunostomy has published favorable findings from its pilot study. Summary EBTs are safe and effective therapies for weight loss when used in conjunction with lifestyle changes and fill an important gap in the management of obesity. There are now six FDA-approved EBTs available and several more in ongoing trials with favorable early findings. More study is needed to understand the role of EBTs used in combination or in sequence with medications and bariatric surgery.

Endoluminal weight loss and metabolic therapies: current and future techniques

Obesity is a public health epidemic associated with a number of comorbidities, most notably type 2 diabetes and hypertension, as well as elevated all-cause mortality. The treatment for obesity and its associated comorbidities has most recently expanded into the field of bariatric endoscopy. This field bridges a gap between lifestyle counseling with or without pharmaceutical treatment and the most effective treatment of obesity, bariatric surgery. Because of its minimally invasive nature, bariatric endoscopic therapy has the potential to appeal to the large sector of the obese population that resists surgery, as well as those early in the onset of obesity. To date, five endoscopic devices have been approved by the U.S. Food and Drug Administration for the treatment of obesity, and many more are in development, undergoing clinical trials, or being used around the world. Here, we present the current state of the field, highlight recent developments, and describe the clinical outcomes of these minimally invasive procedures in terms of weight loss, improvement in metabolic profile, and reduction in comorbidities.

Medical devices for the treatment of obesity

Obesity is a major public health concern that leads to numerous metabolic, mechanical and psychological complications. Although lifestyle interventions are the cornerstone of obesity management, subsequent physiological neurohormonal adaptations limit weight loss, strongly favour weight regain and counteract sustained weight loss. A range of effective therapies are therefore needed to manage this chronic relapsing disease. Bariatric surgery delivers substantial, durable weight loss but limited access to care, perceived high risks and costs restrict uptake. Medical devices are uniquely positioned to bridge the gap between more conservative lifestyle intervention and weight-loss pharmacotherapy and more disruptive bariatric surgery. In this Review, we examine the range of gastrointestinal medical devices that are available in clinical practice to treat obesity, as well as those that are in advanced stages of development. We focus on the mechanisms of action as well as the efficacy and safety profiles of these devices. Many of these devices are placed endoscopically, which provides gastroenterologists with exciting opportunities for treatment.

A new proposed mechanism of action for gastric bypass surgery: Air hypothesis

Roux-en-Y gastric bypass (RYGB) surgery is one of the most effective treatments for obesity and type II diabetes. RYGB was originally believed to work by mechanically restricting caloric intake or causing macronutrient malabsorption. However, such mechanical effects play no role in the remarkable efficacy of gastric bypass. Instead, mounting evidence shows that altered neuroendocrine signaling is responsible for the weight reducing effects of RYGB. The exact mechanism of this surgical response is still a mystery. Here, we propose that RYGB leads to weight loss primarily by inducing a functional shift in the gut microbiome, manifested by a relative expansion of aerobic bacteria numbers in the colon. We point to compelling evidence that gastric bypass changes the function of the microbiome by disrupting intestinal gas homeostasis, causing excessive transit of swallowed air (oxygen) into the colon.

Endoscopic Bariatric and Metabolic Therapies: New and Emerging Technologies

Endoscopic bariatric and metabolic therapies (EBMT) are a new addition to the treatment arsenal for obesity. These include devices that are placed or removed via flexible endoscopy, and procedures that utilize instruments that require flexible endoscopy for the indications of weight loss or treatment of glucose intolerance (from pre-diabetes to diabetes). The EBMTs are generally divided into gastric and small bowel categories, and although individual EBMTs may have unique mechanisms of action, similar themes in proposed mechanism of action are seen in the gastric and small bowel EBMTs, respectively. In this review we will describe the therapies approved for use in the United States or currently in the process of obtaining approval for use in the United States. We will discuss potential mechanisms of action and examine safety and efficacy data.

Endoscopic Bariatric and Metabolic Therapies: Surgical Analogues and Mechanisms of Action

Obesity is a worsening pandemic with numerous related comorbid illnesses. Conservative management including lifestyle modification and medications have limited efficacy. In contradistinction, bariatric surgery is effective, however, with substantial cost and non-negligible morbidity and mortality. As such, a small percentage of eligible patients undergo surgery. Over the past decade, endoscopic bariatric and metabolic therapies have been introduced as a less invasive option for the treatment of obesity and its related comorbid illnesses. This article reviews major endoscopic bariatric and metabolic therapies, their surgical analogues, and proposed mechanisms of action. Clinical trial data for each device also are discussed.

Small Bowel Target Devices and Techniques

The small bowel is a prime target for bariatric and metabolic endoscopic therapies. New insights into the mechanisms of action of surgical therapies have led to new endoscopic therapies for obesity, type 2 diabetes mellitus, and the metabolic syndrome. The development of endoluminal sleeves that bypass the proximal duodenum have replicated some of the effects of surgical bypass procedures. The endoscopic dual-path enteral bypass has created new and treatment options for these conditions. Duodenal mucosal resurfacing offers significant promise for diabetes management. It is hoped that a durable endoscopic therapy for these conditions will be defined and optimized.

The Regulatory Perspectives on Endoscopic Devices for Obesity

The recent increase in US Food and Drug Administration-approved weight-loss devices has diversified obesity treatment options. The regulatory pathways for endoscopically placed weight-loss devices and considerations for clinical trials are discussed, including the benefit-risk paradigm intended to aid in weight-loss-device trial development. Also discussed is the benefit-risk analysis of recently approved endoscopic devices. A strategic priority of the FDA Center for Devices and Radiological Health is to increase the use of patient input in decision making. Thus, we consider how endoscopic weight-loss devices with profiles similar to those that have been approved may be viewed in a patient preference study.

Bariatric endoscopy: current state of the art, emerging technologies, and challenges

Over the last few decades obesity has become a major health issue worldwide. Although dietary and lifestyle changes are the cornerstone of obesity management, it still poses a huge challenge for the majority of patients to permanently change their eating habits. Bariatric endoscopy represents an evolving filed of minimally invasive techniques and procedures for weight loss trying to respond to these challenges by developing new methods with the increasing role of endoscopists in the management of obesity. Areas covered: The aim of this article is to review the role and the advantages of bariatric endoscopy in the management of obesity by providing a comprehensive reference source and evaluating the currently available and emerging endoscopic devices and techniques for weight loss. Expert commentary: Endoscopic methods for weight loss represent a useful armamentarium in the management of obesity by providing improved effectiveness compared with medications, with a lower risk profile than traditional bariatric surgery. Although preliminary results of recently introduced methods are encouraging, many questions remain regarding the safety and efficacy of such interventions. Combining scientific background with advancements in technology is the key strategy for the further development of bariatric endoscopy.