Medical Devices for Obesity Treatment: Endoscopic Bariatric Therapies

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.

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.

Efficacy and Mechanisms of Gastric Volume-Restriction Bariatric Devices

Obesity is a chronic disease that affects over 795 million people worldwide. Bariatric surgery is an effective therapy to combat the epidemic of clinically severe obesity, but it is only performed in a very small proportion of patients because of the limited surgical indications, the irreversibility of the procedure, and the potential postoperative complications. As an alternative to bariatric surgery, numerous medical devices have been developed for the treatment of morbid obesity and obesity-related disorders. Most devices target restriction of the stomach, but the mechanism of action is likely more than just mechanical restriction. The objective of this review is to integrate the underlying mechanisms of gastric restrictive bariatric devices in obesity and comorbidities. We call attention to the need for future studies on potential mechanisms to shed light on how current gastric volume-restriction bariatric devices function and how future devices and treatments can be further improved to combat the epidemic of obesity.

A Preclinical Animal Study of Combined Intragastric Balloon and Duodenal-Jejunal Bypass Liner for Obesity and Metabolic Disease

INTRODUCTION:

Endoscopic bariatric and metabolic therapies can potentially reproduce similar gastric and small intestinal anatomic and physiologic manipulations as Roux-en-Y gastric bypass. This proof of concept animal study was aimed to assess the feasibility, safety, efficacy, and impact on gastrointestinal physiology of combined intragastric balloons (IGB) and duodenal-jejunal bypass liner (DJBL) for the treatment of obesity.

METHODS:

Five Ossabaw pigs were fed a high-calorie diet to develop obesity and were randomly assigned to receive IGB or DJBL in sequence. The weight gain rate was calculated. Fasting and postprandial blood samples were drawn before any intervention (serving as the baseline group) and 1 month after second device insertion (serving as the combination group) to measure gut neurohormonal changes and metabolic parameters.

RESULTS:

Four pigs successfully received a sequential device insertion. One pig developed duodenal sleeve prolapse that was spontaneously resolved. One pig was early terminated because of developing a central line infection. The rate of weight gain in the combination group (0.63 ± 1.3 kg/wk) was significantly lower than the baseline group (1.96 ± 2.17 kg/wk) and numerically lower than after insertion of the IGB (1.00 ± 1.40 kg/wk) or the DJBL (0.75 ± 2.27 kg/wk) alone. A trend of higher postprandial glucagon-like peptide-1 was observed in the combination group compared with the baseline group.

DISCUSSION:

A combination of IGB and DJBL is feasible and well tolerated. A strategy of sequential use of these devices might offer a synergistic approach that can enhance weight loss and metabolic outcomes.

Personalization of Endoscopic Bariatric and Metabolic Therapies Based on Physiology: a Prospective Feasibility Study with a Single Fluid-Filled Intragastric Balloon

BACKGROUND

The intragastric balloon (IGB) is commonly used for weight loss. Identifying patients who are most likely to tolerate and benefit from IGB therapy will optimize outcomes. Our aims were to prospectively utilize a gastric emptying study to predict intolerance and treatment response with a single fluid-filled IGB and to develop a physiologic prediction model with a treatment algorithm.

MATERIALS AND METHODS

A total of 32 patients had a gastric emptying study before and 2-3 months after placement of an IGB. Multiple logistic regression analyses were performed to calculate likelihood ratios and to develop a physiologic prediction model.

RESULTS

Patients in the higher gastric retention quartile at baseline had a 6.2-time higher likelihood ratio for early balloon removal secondary to intolerance (p = 0.013). Utilizing baseline gastric emptying to predict intolerance to the IGB may have prevented 75% of early removal cases. Decreased gastric emptying at 3 months after balloon placement was significantly correlated with percent total body weight loss (%TWBL) at 6 and 12 months (p = 0.01 and p = 0.014, respectively). At 6 months after IGB, patients with no change in their gastric emptying at 3 months lost significantly less weight compared with those with increased gastric retention (median %TBWL = 9.0% [4.5-14.7] versus 17.3% [12.2-24.4], p = 0.016).

CONCLUSION

Utilizing gastric emptying as a physiologic predictor of intolerance and response to the single fluid-filled IGB can improve outcomes. This pilot feasibility trial ushers in the era of personalized endoscopic bariatric therapies to maximize patients' tolerance, cost-effectiveness, and meaningful weight loss.

Endoscopic devices and techniques for the management of bariatric surgical adverse events (with videos)

BACKGROUND AND AIMS

As the prevalence of obesity continues to rise, increasing numbers of patients undergo bariatric surgery. Management of adverse events of bariatric surgery may be challenging and often requires a multidisciplinary approach. Endoscopic intervention is often the first line of therapy for management of these adverse events. This document reviews technologies and techniques used for endoscopic management of adverse events of bariatric surgery, organized by surgery type.

METHODS

The MEDLINE database was searched through May 2018 for articles related to endoscopic management of adverse events of bariatric interventions by using relevant keywords such as adverse events related to "gastric bypass," "sleeve gastrectomy," "laparoscopic adjustable banding," and "vertical banded sleeve gastroplasty," in addition to "endoscopic treatment" and "endoscopic management," among others. Available data regarding efficacy, safety, and financial considerations are summarized.

RESULTS

Common adverse events of bariatric surgery include anastomotic ulcers, luminal stenoses, fistulae/leaks, and inadequate initial weight loss or weight regain. Devices used for endoscopic management of bariatric surgical adverse events include balloon dilators (hydrostatic, pneumatic), mechanical closure devices (clips, endoscopic suturing system, endoscopic plication platform), luminal stents (covered esophageal stents, lumen-apposing metal stents, plastic stents), and thermal therapy (argon plasma coagulation, needle-knives), among others. Available data, composed mainly of case series and retrospective cohort studies, support the primary role of endoscopic management. Multiple procedures and techniques are often required to achieve clinical success, and existing management algorithms are evolving.

CONCLUSIONS

Endoscopy is a less invasive alternative for management of adverse events of bariatric surgery and for revisional procedures. Endoscopic procedures are frequently performed in the context of multidisciplinary management with bariatric surgeons and interventional radiologists. Treatment algorithms and standards of practice for endoscopic management will continue to be refined as new dedicated technology and data emerge.

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.

Standardization of Bariatric Metabolic Procedures: World Consensus Meeting Statement

BACKGROUND

Standardization of the key measurements of a procedure's finished anatomic configuration strengthens surgical practice, research, and patient outcomes. A consensus meeting was organized to define standard versions of 25 bariatric metabolic procedures.

METHODS

A panel of experts in bariatric metabolic surgery from multiple continents was invited to present technique descriptions and outcomes for 4 classic, or conventional, and 21 variant and emerging procedures. Expert panel and audience discussion was followed by electronic voting on proposed standard dimensions and volumes for each procedure's key anatomic alterations. Consensus was defined as ≥ 70% agreement.

RESULTS

The Bariatric Metabolic Surgery Standardization World Consensus Meeting (BMSS-WOCOM) was convened March 22-24, 2018, in New Delhi, India. Discussion confirmed heterogeneity in procedure measurements in the literature. A set of anatomic measurements to serve as the standard version of each procedure was proposed. After two voting rounds, 22/25 (88.0%) configurations posed for consideration as procedure standards achieved voting consensus by the expert panel, 1 did not attain consensus, and 2 were not voted on. All configurations were voted on by ≥ 50% of 50 expert panelists. The Consensus Statement was developed from scientific evidence collated from presenters' slides and a separate literature review, meeting video, and transcripts. Review and input was provided by consensus panel members.

CONCLUSIONS

Standard versions of the finished anatomic configurations of 22 surgical procedures were established by expert consensus. The BMSS process was undertaken as a first step in developing evidence-based standard bariatric metabolic surgical procedures with the aim of improving consistency in surgery, data collection, comparison of procedures, and outcome reporting.

EUS-Guided Intragastric Injection of Botulinum Toxin A in the Preoperative Treatment of Super-Obese Patients: a Randomized Clinical Trial

BACKGROUND

Obesity is a disease that is highly prevalent in Brazil, and the associated comorbidities represent a major global public health challenge. Botulinum toxin type A (BTX-A) is a potent neurotoxin and inhibitor of gastric smooth muscle activity. In theory, BTX-A administration should promote early satiety and weight loss because it delays gastric emptying by inhibiting acetylcholine-mediated peristalsis, which is primarily responsible for gastric motility. Because results in the literature are discrepant, the efficacy of intragastric injections of BTX-A as a primary treatment for obesity remains unknown. The objective of this prospective, double-blind, single-center randomized study was to evaluate the effects of endoscopic ultrasound-guided intragastric BTX-A injections, as a bridge to bariatric surgery, in super-obese patients.

METHODS

Thirty-two super-obese patients were randomized to one of two groups: BTX-A, in which 200 units of BTX-A were injected into the gastric antrum and body; and control, in which the same injections were performed with 0.9% saline. Weight, body mass index (BMI), and loss of excess weight were measured monthly over a 6-month period. Gastric emptying scintigraphy was performed before and after the procedure.

RESULTS

The patients in both groups showed significant weight loss over the course of the study (p < 0.001). There were no statistically significant differences between the groups regarding weight loss, excess weight, total loss of excess weight, total weight loss, or change in BMI.

CONCLUSIONS

Intragastric injection of BTX-A does not appear to be an effective method of achieving preoperative weight loss in super-obese patients.

Changes in Time of Gastric Emptying After Surgical and Endoscopic Bariatrics and Weight Loss: A Systematic Review and Meta-Analysis

BACKGROUND & AIMS

Gastric emptying (GE) is involved in the regulation of appetite. We compared times of GE after different bariatric endoscopic and surgical interventions and associations with weight loss.

METHODS

We performed a comprehensive search of publication databases, through September 14, 2018, for randomized and nonrandomized studies reporting outcomes of weight-loss surgeries. Two independent reviewers selected and appraised studies. The outcome of interest was GE T1/2 (min), measured before and after the procedure. A random-effects model was used to pool the mean change in T1/2 (min) after the intervention. We performed a meta-regression analysis to find associations between GE and weight loss. Heterogeneity was calculated using the I2 statistic. Methodologic quality was assessed.

RESULTS

From 762 citations, the following studies were included in our analysis: 9 sleeve gastrectomies, 5 intragastric balloons, and 5 antral botulinum toxins. After sleeve gastrectomy, the pooled mean reduction in GE T1/2 at 3 months was 29.2 minutes (95% CI, 40.9-17.5 min; I2 = 91%). Fluid-filled balloons increased GE T1/2 by 116 minutes (95% CI, 29.4-203.4 min; I2 = 58.6%). Air-filled balloons did not produce a statistically significant difference in GE T1/2. Antral botulinum injections increased GE T1/2 by 9.6 minutes (95% CI, 2.8-16.4 min; I2 = 13.3%). Placebo interventions reduced GE T1/2 by 6.3 minutes (95% CI, 10-2.6 min). Changes in GE were associated with weight loss after sleeve gastrectomy and intragastric balloons, but not botulinum toxin injections.

CONCLUSIONS

In a systematic review and meta-analysis, we found that sleeve gastrectomy reduced GE T1/2 whereas fluid-filled balloons significantly increased GE T1/2. Air-filled balloons do not significantly change the time of GE, which could account for their low efficacy. Antral botulinum toxin injections produced small temporary increases in GE time, which were not associated with weight loss. Changes in GE time after surgical and endoscopic bariatric interventions correlated with weight loss and might be used to select interventions, based on patients' physiology.

Biomaterials in Gastroenterology: A Critical Overview

In spite of the large diversity of diagnostic and interventional devices associated with gastrointestinal endoscopic procedures, there is little information on the impact of the biomaterials (metals, polymers) contained in these devices upon body tissues and, indirectly, upon the treatment outcomes. Other biomaterials for gastroenterology, such as adhesives and certain hemostatic agents, have been investigated to a greater extent, but the information is fragmentary. Much of this situation is due to the paucity of details disclosed by the manufacturers of the devices. Moreover, for most of the applications in the gastrointestinal (GI) tract, there are no studies available on the biocompatibility of the device materials when in intimate contact with mucosae and other components of the GI tract. We have summarized the current situation with a focus on aspects of biomaterials and biocompatibility related to the device materials and other agents, with an emphasis on the GI endoscopic procedures. Procedures and devices used for the control of bleeding, for polypectomy, in bariatrics, and for stenting are discussed, particularly dwelling upon the biomaterial-related features of each application. There are indications that research is progressing steadily in this field, and the establishment of the subdiscipline of "gastroenterologic biomaterials" is not merely a remote projection. Upon the completion of this article, the gastroenterologist should be able to understand the nature of biomaterials and to achieve a suitable and beneficial perception of their significance in gastroenterology. Likewise, the biomaterialist should become aware of the specific tasks that the biomaterials must fulfil when placed within the GI tract, and regard such applications as both a challenge and an incentive for progressing the research in this field.

Fluid-Filled Versus Gas-Filled Intragastric Balloons as Obesity Interventions: a Network Meta-analysis of Randomized Trials

BACKGROUND

Four commercially available intragastric balloons have been used for the management of obesity and underwent randomized controlled trials (RCTs), and we aimed to compare them using a network meta-analysis approach.

METHODS

Several databases were queried from inception to May 26, 2017, and we included RCTs enrolling patients treated with Orbera, Heliosphere, ReShape Duo, and Obalon compared with another balloon, sham, or open-label control group. Two investigators independently abstracted data. A random effects frequentist network meta-analysis and relative ranking of agents using surface under the cumulative ranking probabilities were performed.

RESULTS

We included 15 trials at low risk of bias (only two were head-to-head). Compared to control groups, the two fluid-filled devices were associated with significant outcome (% total body weight loss) at 6 months: Orbera, 6.72% (95% CI, 5.55, 7.89) and ReShape Duo 4% (95% CI 2.69, 5.31). Only one of the two gas-filled devices was associated with significant outcome at 6 months: Obalon 3.3% (95% CI 2.30, 4.30), and not the second: Heliosphere 6.71% (95% CI - 0.82, 14.23). Fluid-filled devices had the highest likelihood of superiority in achieving the outcome at 6 months (96.8%) and at 12 months (96.6%). The quality of evidence was high for comparisons against control.

CONCLUSIONS

Fluid-filled balloons are more likely to produce weight loss compared to gas-filled balloons or lifestyle intervention. However, they may be associated with a higher rate of intolerance and early removal. This information will aid clinicians in device selection and engaging patients in shared decision-making.

Malnutrition in obesity before and after bariatric surgery

Bariatric surgeries are considered the only effective way of weight loss therapy in morbidly obese patients, i.e. body mass index ≥ 35. However, micronutrient deficiencies and malnutrition are common after most bariatric procedures and thus, pre- and postoperative nutritional assessment and corrections are advised. The present review is presented in an effort to describe in some detail about prevalence, and mechanisms of macro- and micronutrient deficiencies in obese and post-bariatric surgery individuals. We also aimed to summarize the data on screening and supplementation of macro- and micronutrients before and after bariatric surgeries.

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.

Various Intragastric Balloons Under Clinical Investigation

Obesity is a chronic disease with an exponentially increasing incidence rate, and its negative effects are well documented in numerous studies. As a result, the importance of bariatric therapy cannot be overemphasized, and many bariatric treatment methods with varying mechanisms have been developed. Of the available treatment methods, intragastric balloons, introduced in the 1980s, have been shown to be a safe and effective treatment modality; various intragastric balloon products have been developed and are currently being widely used in clinical settings. However, the disadvantages of intragastric balloons, such as unclear long-term weight loss benefits and complications experienced during insertion and removal, preclude their wider use. In this review, we discuss different intragastric balloon products, focusing on those under clinical investigation, and suggest future research directions.