Treatment of morbid obesity by intraparietogastric administration of botulinum toxin: a randomized, double-blind, controlled study

Intragastric botulinum toxin injection for weight loss: current trends, shortcomings and future perspective

The administration of botulinum toxin A (BTA) into the gastric wall has emerged as a novel endoscopic bariatric procedure. Although over 20 years have elapsed since the initial human trial of intragastric BTA injection, considerable debate remains surrounding the safety, efficacy, and procedural instructions of this approach. The current literature exhibits discrepancies in the methodologies employed across studies, including differences in the dosage of BTA administered, injection site, number and depth of injections, post-procedural dietary modifications, and follow-up duration. This study reviewed the state-of-the-art use of BTA for weight loss and focused on the clinical evidence of the therapeutic applications of BTA for obesity. Studies with consistent outcome measures and methodologies are necessary to thoroughly assess the potential effects of BTA on weight management.

Intragastric injection of botulinum toxin in the treatment of obesity: a single-center study

Background

In recent years, various novel surgical and non-surgical therapeutic options have been developed for treating obesity. Due to its disputed success, intragastric botulinum toxin A (BTX-A) injection is still being debated.

Objectives

We aim to contribute to this controversial issue in the literature by sharing our center's findings regarding intragastric BTX-A injections in the treatment of obesity.

Design

Patients with a body mass index (BMI) of greater than 25 kg/m2 and at least one obesity-related complication, or a BMI of greater than 30 kg/m2 without complications, were eligible for the study if they were between the ages of 18 and 65.

Methods

Following the same procedure, two endoscopists administered BTX-A to all patients. All patients were evaluated for obesity by measuring their lipid profile, hormone profile, and insulin resistance level before treatment.

Results

In our study on 82 patients, we saw a significant mean weight loss (-9.2 kg, p < 0.001) in the second month, and there was no additional mean weight loss in the sixth month of follow-up. In addition, this result seems to be independent of the patient's insulin resistance. We did not see any serious side effects in any of the patients.

Conclusion

Although the use of intragastric injection of BTX-A in the treatment of obesity is a controversial issue, we showed in our study that it causes significant weight loss. Further studies are needed on this subject, as it can be a safe method when the ideal dose and application site are combined with appropriate patient selection.

Treatment of obesity with intragastric injection of botulinum toxin. Is it worth the pinch? An overview of systematic reviews and meta-analysis

BACKGROUND AND AIMS

Αvaialble evidence regarding the effectiveness of intragastric injection of botulinum toxin in reducing anthropometric indices of subjects with obesity is conflicting. We evaluated the existing evidence and perform a meta-analysis to assess the efficacy of intragastric botulinum toxin in treating obesity.

METHODS

We identified published systematic reviews evaluating the efficacy of intragastric injection of botulinum toxin in patients with overweight or obesity and additionally performed a systematic literature search to retrieve randomized controlled trials on this topic. A random-effects meta-analysis was performed to synthesize the existing studies.

RESULTS

A total of four systematic reviews were included in our overview of systematic reviews and six randomized controlled trials were included in our meta-analysis. Compared to placebo, intragastric injection of botulinum toxin was ineffective in reducing body weight and body mass index after the application of the Knapp-Hartung adjustment (MD = -2.41 kg, 95%CI = -5.21 to 0.38, I² =59% and MD = -1.43 kg/m², 95%CI = -3.04 to 0.18, I² =62%, respectively). Moreover, treatment with intragastric injection with botulinum toxin was not superior to placebo in decreasing waist and hip circumference.

CONCLUSIONS

Based on the available evidence, intragastric injection with botulinum toxin is an ineffective procedure in reducing body weight and body mass index when the Knapp-Hartung method was applied.

[Endoscopic intragastric injection of botulinum toxin in the treatment of patients with morbid obesity: opportunities and prospects]

The authors consider modern epidemiological and demographic data on morbid obesity. Literature review is devoted to non-surgical treatment of patients with morbid obesity. The authors analyze the results of experimental and clinical studies on endoscopic intragastric injection of botulinum toxin and bariatric efficacy of this approach. The indications for endoscopic intragastric injection of botulinum toxin and advantages of this technique are clearly formulated. The authors identified the most significant criteria for objective assessment of clinical effectiveness of endoscopic intragastral injection of botulinum toxin, as well as scientific and methodological principles necessary for this technique. Clinical efficacy of intragastric injection of botulinum toxin including overweight loss, anorexigenic and gastroparetic effects indicates inconsistent results and certain unresolved problems. Thus, large-scale multiple-center randomized controlled trials and multivariate analysis are required to determine the role of endoscopic intragastric injection of botulinum toxin in complex treatment of patients with morbid obesity.

Comparison of The Short-Term Effects of Intragastric Balloon and Botulinum Toxin Injection On Weight Loss

Aim: To compare the effects of endoscopic intragastric balloon (IGB) placement and intragastric botulinum toxin-A (BTX-A) injection in terms of weight loss among patients with non-morbid obesity. Methods: This retrospective single center study was conducted between 01.08.2020 and 01.01.2022. A total of 39 patients with a body mass index (BMI) of &lt;40 without comorbidities were included in the study. Nineteen underwent intragastric BTX-A injection and 20 underwent IGB placement. Patients were evaluated 1 month and 6 months after the procedures. Results: Mean age was 39.4 ± 8.6 in the BTX-A group and 37.3 ± 10.4 in the IGB group (p = 0.496). 78.9% of the BTX-A group and 75.0% of the IGB group were female (p = 1.000). In both groups, the median weight 1 month after the procedure was significantly lower than before the procedure, and the median weight 6 months after the procedure was significantly lower than 1 month after the procedure (p&lt;0.001 for both groups). The median weight loss in the IGB group at both the 1st and 6th months was significantly greater than the corresponding values of the BTX-A group (p &lt; 0.001 for both). Conclusion: IGB insertion appears to be a more successful endoscopic bariatric procedure than intragastric BTX-A injection, as measured by weight loss at post-intervention 1 month and 6 months. IGB may be preferred in patients with a BMI below 40 without obesity-related comorbidity.

Effect of Intragastric Botulinum Type A Injection Combined with a Low-Calorie High-Protein Diet in Adults with Overweight or Obesity

(1) Background/aims: Intragastric botulinum toxin A injection (IGBI) combined with diet control is a new and effective weight loss method for grade 2 obese patients. However, the application of IGIB on overweight or obese adults still needs further research to confirm its efficacy. (2) Methods: We retrospectively collected medical data from 1 July 2021 to 1 January 2022 from a total of 71 patients without diabetes who participated in the bariatric clinic with a body mass index (BMI) > 25 kg/m2. Forty-nine participants opted for intragastric botulinum injection (IGBI) using 300 units of botulinum injected into the antrum, body, and fundus, followed with a low-calorie high-protein diet course. Another 22 people participated only in the low-calorie high-protein diet course as a placebo group. This study analyzes the weight loss percentage of the two groups. Adverse events after IGBI are also reported in a safety assessment. (3) Results: In terms of the characteristics of the two groups, the mean BMI was 29.3 kg/m2 in the IGBI group and 28.0 kg/m in the placebo group (p = 0.63 without significant difference). Comparing the percent weight loss from baseline in the two groups after 12 weeks, the IGBI group lost 11.5% of their body weight and the placebo group lost 1.8%. In terms of group analysis, the percentages of participants with a weight reduction of at least 5% for the IGBI and placebo groups were 95% and 4%, respectively. For weight reduction of at least 10%, these values for the IGBI and placebo groups were 63% and 4%, respectively. In terms of adverse events after IGBI for 12 weeks, 12 participants (24.4%) had constipation, which was the main side effect. No serious adverse events were observed during the study period. (4) Conclusion: The combination of a low-calorie high-protein diet and IGBI is an effective and safe procedure in overweight or obese adults for weight reduction, but further larger studies are needed.

Intragastric injection of botulinum toxin A for weight loss: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND AND AIM

Intragastric botulinum toxin A (BTA) injection is a potential treatment for weight reduction in obese patients. Current studies yielded conflicting results. We performed a systematic review and meta-analysis of randomized controlled trials (RCTs) to assess the efficacy of intragastric BTA injection for weight management.

METHODS

We searched several databases to identify RCTs evaluating intragastric BTA injections for obesity. We applied random-effects models for all meta-analyses due to heterogeneity in the included studies. The mean difference (MD) and 95% confidence interval (CI) were calculated for continuous outcomes.

RESULTS

A total of 6 RCTs including 192 subjects met the inclusion criteria and were included for the meta-analysis. Although the pooled data from six studies showed no difference in the absolute weight loss between intragastric BTA injection and control, subgroup analysis showed a significantly decreased absolute weight after a BTA injection dose ≥ 200 U (MD, -2.04 kg; 95% CI, -3.96 to -0.12) and after multiple injection regions in the stomach combined with diet control (MD, -4.44 kg; 95% CI, -6.54 to -2.33 kg) compared with the control. Regarding absolute weight loss, the impact of endoscopic ultrasound-guided injection and follow-up duration showed no difference. Intragastric BTA injection had a significant change in body mass index (MD, -1.25 kg/m2 ; 95% CI, -2.18 to -0.32 kg/m2 ) and prolonged gastric half-emptying time (MD, 11.37 min; 95% CI, -3.69 to 19.06 min).

CONCLUSION

Intragastric BTA injection is effective for obesity treatment, and adequate doses (≥ 200 U), multiple gastric injection regions, and combined diet control are crucial. However, given the small sample size and limited power, caution should be exercised.

Impact of Vagotomy on Postoperative Weight Loss, Alimentary Intake, and Enterohormone Secretion After Bariatric Surgery in Experimental Translational Models

Obesity may be treated by bariatric procedures and is related to enterohormone release modulation. Nevertheless, a majority of commonly used surgical procedures have a significant impact on vagus nerve function by breaking the connections with its gastric branches. In the case of an intragastric balloon (BAL), this interaction is unclear. However, BAL-induced weight reduction is not long-lasting. Interestingly, this method has not been used in combination with vagotomy (VAG). Thus, we evaluated, for the first time, the short- and long-term effects of combined BAL and VAG using the animal-based translational model and compared these effects with sleeve gastrectomy (SG) and Roux-en-Y gastric bypass (RYGB). Wistar rats were fed a high-calorie diet for 8 weeks to induce obesity before SG, RYGB, BAL + / - VAG. Animals' weight and eating behaviors were monitored weekly. After 90 days, serum samples were collected to evaluate postprandial and fasting GLP-1, GIP, PYY, ghrelin, glucagon, insulin, leptin, and pancreatic polypeptide concentrations by fluorescent assay. VAG, SG, RYGB, and BAL + VAG significantly reduced body weight 30 and 90 days after surgery. BAL alone induced temporal weight reduction observed after 30 days, reversed after 90 days. Calories intake was reduced at the first half of the observation period in all groups. Fluid intake was reduced in all groups except SG and BAL. Enterohormone profile for BAL + VAG was comparable to SG and RYGB but not BAL. VAG and BAL + VAG but not BAL alone maintain weight reduction, alimentary intake changes, and enterohormone release after long-term observation. VAG may improve the effectiveness of bariatric procedures for obesity treatment in clinical practice.

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.

The Multispecialty Toxin: A Literature Review of Botulinum Toxin

Botulinum toxin (BoNT) is a potent biological exotoxin produced from Clostridium botulinum. Although it was first used therapeutically to treat strabismus, its clinical role has since expanded rapidly over the years to include treatment of a variety of head and neck, gastrointestinal, urogenital, musculoskeletal, neurological, dermatological, and cosmetic disorders. The main purpose of this review is to provide a brief updated overview of the history, mechanism of action, and clinical applications of BoNT therapy across multiple medical specialties, including the most common adverse effects and recommended Botox dosages.

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.

The GAMMA concept (gastrointestinal activity manipulation to modulate appetite) preliminary proofs of the concept of local vibrational gastric mechanical stimulation

BACKGROUND

Mechanical stimulation of the stretch receptors of the gastric wall can simulate the presence of indigested food leading to reduced food intake. We report the preliminary experimental results of an innovative concept of localized mechanical gastric stimulation.

METHODS

In a first survival study, a biocompatible bulking agent was injected either in the greater curvature (n = 8) or in the cardia wall (n = 8) of Wistar rats. Six animals served as sham. Changes of bulking volume, leptin levels and weight gain were monitored for 3 months. In a second acute study, a micro-motor (n = 10; MM) or a size-paired inactive device (n = 10; ID) where applied on the cardia, while 10 additional rats served as sham. Serum ghrelin and leptin were measured at baseline and every hour (T0-T1-T2-T3), during 3 h. In a third study, 24 implants of various shapes and sizes were introduced into the gastric subserosa of 6 Yucatan pigs. Monthly CT scans and gastroscopies were done for 6 months.

RESULTS

Weight gain in the CW group was significant lower after 2 weeks and 3 months when compared to the shame and GC (p = 0.01/p = 0.01 and p = 0.048/p = 0.038 respectively). Significant lower increase of leptin production occurred at 2 weeks (p = 0.01) and 3 months (p = 0.008) in CW vs. SG. In the MM group significant reduction of the serum ghrelin was seen after 3 h. Leptin was significantly increased in both MM and ID groups after 3 h, while it was significantly reduced in sham rats. The global device retention was 43.5%. Devices with lower profile and with a biocompatible coating remained more likely in place without complications.

CONCLUSIONS

Gastric mechanical stimulation induced a reduced weight gain and hormonal changes. Low profile and coated devices inserted within the gastric wall are more likely to be integrated.

Evaluation of endoscopic ultrasound-guided gastric botulinum toxin injections in the treatment of obesity

Background

Obesity is rapidly emerging as one of the greatest challenges of human health. Many randomized trials and open-label human studies described conflicting results of gastric intra-muscular injections of botulinum toxin type A (BTA). Endoscopic ultrasound (EUS) guidance can assure BTA injection into the subserosal layer and muscularis propria of the gastric wall which may optimize the efficacy of injection. The aim of the study is to assess the efficacy and safety of EUS-guided gastric BTA injections in weight reduction for obese subjects.

Results

The present study included 25 patients (2 males and 23 females with mean age 35.84 ± 7.776). For nutrient drink tests, median maximum tolerated volumes (MTVs) decreased from 720 cc (range 480–1680) as a baseline value 2 weeks before BTA injection to 360 cc (range 140–820) at 16 weeks after injection. Mean body weight reduction was 11.92 kg (10.8%) after 16 weeks of BTA injection. Mean body weight continued to decrease during the study period from a baseline value of 110 to 98 kg with significant reduction of mean BMI from baseline value of 41.2 to 36.7 at 16 weeks after BTA injection (p < 0.001). The study was completed without major adverse events.

Conclusion

EUS-guided BTA injection into the antral subserosa and muscularis propria could be an effective technique for weight reduction, or as a bridge for surgery, which can be done safely with minimal complications.

Trial registration

NCT03901040

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.

Intragastric Botulinum Toxin A Injection Is an Effective Obesity Therapy for Patients with BMI > 40 kg/m2: a Systematic Review and Meta-analysis

We conducted a systematic review and meta-analysis to assess the efficacy of intragastric BTA injection in patients with obesity and morbid obesity. Five RCTs were identified. Intragastric BTA injection was no superior to saline in absolute weight loss or BMI change, but significantly lengthened the gastric emptying time (MD, 15.57; 95% CI, 8.75 to 22.38). In meta-regression analysis, the absolute weight loss was lower in the patients with high baseline BMI. In subgroup analysis, the use of BTA in absolute weight loss was significantly lower among the patients with baseline BMI more than 40 kg/m2 (MD, - 5.31; 95% CI, - 6.17 to - 4.45). The benefit of intragastric BTA injection in reduction of absolute weight was observed in patients with baseline BMI more than 40 kg/m2.

How Taking into Account the Pyloric Tonus Contributes to Treatment Success While Administering Gastric "Botulinum Toxin A" for Weight Loss

PURPOSE

To analyze how considering the structure of normotonic pylorus (NP) or hypotonic pylorus (HP) contributes to treatment success in patients administered gastric botulinum toxin A for weight loss.

MATERIALS AND METHODS

We measured body mass indexes (BMIs) of the patients who applied for gastric botulinum toxin A (BTA) for weight loss, before and 6 months after the procedure. The patients' pylori were classified as normotonic pylorus (NP) if, during endoscopy, they had a normal peristaltic motion and was closing completely, and as hypotonic pylorus if they were not closing properly or were aperistaltic. We compared the patients' mean pre-operative and 6-month post-operative BMIs. The groups were compared using the chi-square test where a p ˂ 0.05 was considered significant.

RESULTS

The study included 178 patients administered gastric BTA. In the assessment made without considering the pyloric structure, the mean BMI decreased from 34.76 ± 7.65 to 33.09 ± 7.80 kg/m², while the difference was not statistically significant (p ˂ 0.06). Conversely, in the analysis performed considering the structure of pylorus, the mean pre-operative BMI of the 45 patients with HP structure was 35.16 ± 7.07 kg/m² which decreased to 35.11 ± 7.03 kg/m² 6 months after the procedure; hence, the difference was not statistically significant (p ˂ 0.7). The mean pre-operative BMI of the 133 patients with NP structure, 34.63 ± 7.84 kg/m², decreased to 32.40 ± 8.05 kg/m² 6 months after the procedure and the difference was statistically significant (p ˂ 0.05)*.

CONCLUSION

We advise to be selective in BTA administration and to administer BTA to the patients who, endoscopically, have a NP structure.

The Positive Effects of a Calorie-Restricting High-Protein Diet Combined with Intragastric Botulinum Toxin Type A Application Among Morbidly Obese Patients: A Prospective, Observational Analysis of Eighty-Seven Grade 2 Obese Patients

PURPOSE

Many studies evaluating the effect of intragastric botulinum toxin type A injection (IG-BTxA) for the treatment of obesity have been published. However, none of these studies combined this procedure with a calorie-restricting high-protein diet. Herein, we aimed to evaluate the effects of IG-BTxA application combined with a calorie-restricting high-protein diet.

MATERIALS AND METHODS

This prospective cohort study is conducted with eighty-seven grade 2 obese patients treated between January 2019 and August 2019. Group 1: IG-BTxA + refused to consult the dietitian; group 2: IG-BTxA + get calorie-restricting high-protein diet; group 3: only get a calorie-restricting high-protein diet. Loss of weight, treatment adaptation (visual analog scale score), the status and changes of comorbid conditions, and changes in eating behaviors (Self-Regulation of Eating Behaviour Questionnaire score) were assessed.

RESULTS

Loss of weight, treatment adaptation, and positive behavioral change in eating preferences were significantly higher in group 2 (p = 0.01; p = 0.001; p < 0.01, respectively). Additionally, the decrease in medication requirement for diabetes and hypertension was higher in group 2 (p < 0.05).

CONCLUSION

IG-BTxA application before calorie-restricting high-protein diet facilitates adaptation to the new diet style and helps to lose weight faster in grade 2 obese patients. Also, more positive results were achieved in terms of controlling comorbid diseases.

Gastrointestinal Uses of Botulinum Toxin

Botulinum toxin (BT), one of the most powerful inhibitors that prevents the release of acetylcholine from nerve endings, represents an alternative therapeutic approach for "spastic" disorders of the gastrointestinal tract such as achalasia, gastroparesis, sphincter of Oddi dysfunction, chronic anal fissures, and pelvic floor dyssynergia.BT has proven to be safe and this allows it to be a valid alternative in patients at high risk of invasive procedures but long-term efficacy in many disorders has not been observed, primarily due to its relatively short duration of action. Administration of BT has a low rate of adverse reactions and complications. However, not all patients respond to BT therapy, and large randomized controlled trials are lacking for many conditions commonly treated with BT.The local injection of BT in some conditions becomes a useful tool to decide to switch to more invasive therapies. Since 1980, the toxin has rapidly transformed from lethal poison to a safe therapeutic agent, with a significant impact on the quality of life.

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.

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.

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.

The Role of Endoscopic Intra-Gastric Botulinum Toxin-A for Obesity Treatment

Obesity prevalence has been increasing with devastating health and economic consequences. Botulinum toxin type A (BTX-A), a neurotoxin, is used clinically for conditions characterized by prolonged muscular contraction. Its inhibitory effects on gastric smooth muscles, in theory, make it a potential agent for obesity treatment through delayed gastric emptying and increased satiety. This review aims to examine the evidence for the use of endoscopic BTX-A injection for treating obesity. The literature search identified 60 articles with 11 primary studies as relevant for the scope of the review. Several studies have been conducted to examine the effect of BTX-A injections on obesity, including both animal and human studies. Current evidence from identified studies does not demonstrate sustained weight loss through the use of endoscopic BTX-A injection.

Obesity Treatment with Botulinum Toxin-A Is Not Effective: a Systematic Review and Meta-Analysis

The effectiveness of gastric injections of botulinum toxin-A (BTA) as primary treatment for obesity is not well known since results in literature are discrepant. Hence, we aimed to systematically review and meta-analyze the available data to assess the real effect of BTA therapy. We searched MEDLINE, Embase, Cochrane, SCOPUS, EBSCO, LILACS, and BVS. We considered eligible only randomized controlled trials enrolling obese patients comparing BTA versus saline injections. Our initial search identified 8811 records. Six studies fulfilled eligibility criteria. After critical appraisal, two articles were excluded and we meta-analyzed the remainder. The mean difference for absolute weight loss and BMI reduction were 0.12 [CI 95%, - 1.14, 1.38] and - 0.06 [95% CI, - 0.92, 0.81], respectively. Therefore, we concluded that treatment of obesity with BTA is not effective.

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.

Selected Endoscopic Gastric Devices for Obesity

This article focuses on the stomach target devices that are currently in various stages of development. Approved intragastric balloons, devices targeting small bowel and aspiration techniques, are described in other contributions to this issue. Bariatric endoscopic devices targeting the stomach directly alter gastric physiology and promote weight loss by potentially changing functional gastric volume, gastric emptying, gastric wall compliance, neurohormonal signaling, and, thereby, satiety. Many stomach-targeting devices are on the horizon for clinical use, and further study will determine the safety and efficacy for clinical use.

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.

Recent Trends in Endoscopic Management of Obesity

Obesity remains a tremendous public health, clinical, and scientific challenge globally. Conventional approaches in the management of obesity offer limited potential for sustained weight loss. Bariatric surgery, although it represents the most effective weight loss treatment, has its own risks and is associated with substantial costs and limited patient applicability. Endoscopic weight loss procedures are considered as the major breakthrough in the management of obesity. Endoluminal interventions performed entirely through the gastrointestinal tract have evolved as a result of an attempt to replicate some of the anatomical features and the physiological effects of the traditional weight loss surgery while being reversible, less invasive, and more cost-effective. Restrictive procedures act to decrease gastric volume by space-occupying devices and/or by suturing or stapling techniques that alter gastric anatomy, whereas malabsorptive procedures tend to create malabsorption by preventing food contact with the duodenum and proximal jejunum. Other procedures act by influencing gastric function (gastric botulinum injections, gastric pacing, and vagal nerve blocking) or by gastric aspiration. It is important to underline that the majority of endoscopic weight loss procedures are still being evaluated and are not yet available routinely. Even though some of the techniques and devices that have recently emerged have demonstrated promising short-term results, evidence on their safety and long-term efficacy from well-designed and well-conducted research should be given before they can become an inherent part of everyday clinical practice. Given the rapid development of endoscopic weight loss procedures, this review considers the current state and recent trends in endoscopic management of obesity.

Botulinum Toxin A for Controlling Obesity

Rapid growth of the overweight population and the number of obese individuals in recent decades suggests that current strategies based on diet, exercise, and pharmacological knowledge are not sufficient to address this epidemic. Obesity is the result of a high caloric intake and energy storage, not counterbalanced by an equally important energy expense. Botulinum toxin type A (BoNT-A) use is rapidly expanding to include treatment of a variety of ophthalmological, gastrointestinal, urological, orthopedic, dermatological, secretory, painful, and cosmetic disorders. Many studies evaluating the effect of BoNT-A in gastric antrum e/o fundus for the treatment of obesity have been published. This treatment modality was based on the observation that gastric injection of BoNT-A in laparatomized rats induced a significant reduction of food intake and body weight. These studies have been published yielding debated results. Differences in the selection of patients, the doses of BoNT-A, the method of administration of the toxin, and the instruments of evaluation of some parameters among these studies may be the cause. In this review, it will study the state-of-the-art use of BoNT-A in obesity basic science models and review the clinical evidence on the therapeutic applications of BoNT-A for obesity.

Treating morbid obesity in cirrhosis: A quest of holy grail

The problem of obesity is increasing worldwide in epidemic proportions; the situation is similarly becoming more common in patients with cirrhosis which negatively affect the prognosis of disease and also makes liver transplantation difficult especially in the living donor liver transplantation setting where low graft to recipient weight ratio negatively affects survival. Treatment of obesity is difficult in cirrhosis due to difficulty in implementation of lifestyle measures, limited data on safety of anti-obesity drugs and high risk of surgery. Currently approved anti-obesity drugs have limited data in patients with cirrhosis. Bariatric surgery remains an option in selected compensated cirrhotic patients. Endoscopic interventions for obesity are emerging and are quite promising in patients with cirrhosis as these are minimally invasive. In present review, we briefly discuss various modalities of weight reduction in obese patients and their applicability in patients with cirrhosis.

Treatment of gastrointestinal sphincters spasms with botulinum toxin A

Botulinum toxin A inhibits neuromuscular transmission. It has become a drug with many indications. The range of clinical applications has grown to encompass several neurological and non-neurological conditions. One of the most recent achievements in the field is the observation that botulinum toxin A provides benefit in diseases of the gastrointestinal tract. Although toxin blocks cholinergic nerve endings in the autonomic nervous system, it has also been shown that it does not block non-adrenergic non-cholinergic responses mediated by nitric oxide. This has promoted further interest in using botulinum toxin A as a treatment for overactive smooth muscles and sphincters. The introduction of this therapy has made the treatment of several clinical conditions easier, in the outpatient setting, at a lower cost and without permanent complications. This review presents current data on the use of botulinum toxin A in the treatment of pathological conditions of the gastrointestinal tract.

Advances in the Endoscopic Management of Obesity

Obesity has become a worldwide epidemic with significant impact on quality of life, morbidity, and mortality rates. Over the past two decades, bariatric surgery has established itself as the most effective and durable treatment for patients with obesity and its associated comorbidities. However, despite the use of minimally invasive techniques, bariatric surgery is associated with complications in approximately 15% of patients, has a substantial cost, and is used by only 1% of patients who are eligible. Therefore, there is a need for effective minimally invasive therapies, which will be utilized by the large proportion of obese patients who are in desperate need of treatment but are not receiving any. Endoscopic approaches to the management of obesity have been developed, with the aim of delivering more effective, durable, and safer methods of weight reduction. In this paper, we review currently available and future endoscopic therapies that will likely join the armamentarium used in the management of obesity.

The role of endoscopy in bariatrics: past, present, and future

The exponential increase in the rate of obesity and its associated co-morbidities has increased the demand for bariatric surgery. Over the past few decades, surgical weight reduction by gastric restriction, malabsorption, or a combination of both has been the preferred approach to achieve sustained weight loss in the morbidly obese. Although extremely effective, surgical procedures carry significant complications and risk with mortality rates of 1%. Because of the cost, surgical risk, and complications, there is a demand for less invasive procedures. Endoscopic approaches include placement of endoluminal space-occupying devices, stapling devices to reduce gastric volume, barrier devices to reduce small bowel absorptive area, and methods to regulate gastric emptying. Current and ongoing studies have delivered promising results across many aspects of endoscopic approaches. However, many technical obstacles still exist that have to be resolved with further research before endoscopic bariatrics can be widely deployed. At present the role of endoscopy is well established in preoperative evaluation as well as in recognition and management of many postoperative complications in bariatrics. In this article, we review the current and future endoscopic methods for weight reduction that are either in practice or in testing.

Gastric antral injections of botulinum toxin delay gastric emptying but do not reduce body weight

BACKGROUND & AIMS

Gastric injections of botulinum toxin A (BTA) have been reported to delay gastric emptying, increase satiation, and reduce body weight, but there are few data from randomized, placebo-controlled studies.

METHODS

We enrolled 60 obese participants in a 24-week, double-blind, randomized, placebo-controlled, concealed allocation trial to compare the effects of gastric antral injections of BTA (100, 300, or 500 U) and saline placebo. The study was conducted at an outpatient clinical research unit. Participants were given one set of injections of BTA or placebo into the gastric antral muscularis propria by using endoscopic ultrasound guidance. Gastric emptying of solids was measured by scintigraphy; we also measured body weight, satiation (maximum tolerated volume in a caloric liquid drink test), calorie intake (by food frequency questionnaire), gastrointestinal symptoms, and psychological aspects of eating behavior (by rating scale).

RESULTS

Compared with baseline values, 2 weeks after injections, the mean half-time for gastric emptying of solids increased by 0.8, 14, 24, and 14 minutes among subjects given placebo, 100, 300, or 500 U BTA, respectively (P = .24 overall, P = .04 for the group given 300 U vs placebo); 16 weeks after the injections, mean body weights were reduced by 2.2, 0.2, 2.3, and 3.0 kg in these groups, respectively. There were no statistically significant differences in mean body weight change, satiation volume, caloric intake, gastrointestinal symptoms, or psychological aspects of eating behavior among groups.

CONCLUSIONS

Gastric antral injections of BTA may delay gastric emptying at a dose of 300 U but do not cause early satiety, altered eating behaviors, or loss of body weight. Clinicaltrials.gov identifier: NCT00976443.

Obesity and the elderly

The prevalence of obesity is rising progressively, even among older age groups. By the year 2030 to 2035 over 20% of the adult US population and over 25% of the Europeans will be aged 65 years or older. The predicted prevalence of obesity in Americans, 60 years and older was 37% in 2010. The predicted prevalence of obesity in Europe in 2015 varies between 20% and 30% dependent on the model used. This means 20.9 million obese 60 years or older people in the United States in 2010 and 32 million obese elders in 2015 in EU. Although cutoff values of body mass index, waist circumference, and percentages of fat mass have not been defined for the elderly, it is clear from several meta-analyses that mortality and morbidity associated with overweight and obesity only increases at a body mass index >30 kg/m(2). Thus, treatment should only be offered to patients who are obese rather than overweight and who have functional impairments, metabolic complications, or obesity-related diseases, that can benefit from weight loss. The weight loss therapy should minimize muscle and bone loss and vigilance as regards the development of sarcopenic obesity--a combination of an unhealthy excess of body fat with a detrimental loss of muscle and fat-free mass including bone--is important. Lifestyle intervention should be the first step and consists of a diet with a 500 kcal energy deficit and an adequate intake of protein of high biological quality, together with calcium and vitamin D, behavioral therapy, and multicomponent exercise. Multicomponent exercise includes flexibility training, balance training, aerobic exercise, and resistance training. The adherence rate in most studies is around 75%. Knowledge of constraints and modulators of physical inactivity should be of help to engage the elderly in physical activity. The role of pharmacotherapy and bariatric surgery in the elderly is largely unknown as in most studies people aged 65 years and older were excluded.

Endoscopic approaches to obesity

Given the emerging role of endoscopic procedures in the treatment of obesity and rapid changes in endoscopic technologies and techniques, this review considers the current state of endoscopic management of obesity. Endoluminal interventions performed entirely through the GI tract by using flexible endoscopy offer the potential for an ambulatory weight loss procedure that may be safer and more cost- effective compared with current surgical approaches. Endoscopic techniques attempt to mimic the anatomic features of bariatric surgery. Accordingly, there are two main endoscopic weight loss modalities - restrictive and malabsorptive. Restrictive procedures act to decrease gastric volume by space-occupying prosthesis and/or by suturing or stapling devices, while malabsorptive procedures tend to create malabsorption by preventing food contact with the duodenum and proximal jejunum. The former include intragastric balloon treatment, endoluminal vertical gastroplasty, transoral gastroplasty and transoral endoscopic restrictive implant system, while the latter include duodenojejunal bypass sleeve. Gastroduodenojejunal bypass sleeve is a combination of both procedures. Except for intragastric balloon, all mentioned procedures are rather new, tested on a small number of human subjects, with a high rate of success, but with limited knowledge on safety and long-term efficacy. The role of gastric electrical stimulation and intragastric injections of botulinum toxin in obesity treatment is also considered as is the role of minimally invasive bariatric endoscopic interventions.

Endoscopic treatment of obesity

BACKGROUND

The increasing incidence of obesity and overweight among children and adolescents will be reflected by the imminent increase in the number of obese patients who require more definitive methods of treatment. There is great interest in new, safe, simple, nonsurgical procedures for weight loss.

OBJECTIVE

To provide an overview of new endoscopic methods for the treatment of obesity.

METHODS

An English-language literature search on endoscopic interventions, endoscopically placed devices and patient safety was performed in the MEDLINE and Cochrane Library databases.

RESULTS

The literature search yielded the following weight loss methods: space-occupying devices (widely used), gastric capacity reduction, modifying gastric motor function and malabsorptive procedures. A commercially available intragastric balloon was the most commonly used device for weight loss. In specific subgroups of patients, it improved quality of life, decreased comorbidities and served as a bridge to surgery. More evidence regarding the potential benefits and safety of other commercially available intragastric balloons is needed to clarify whether they are superior to the most commonly used one. Moreover, early experiences with transoral gastroplasty, the duodenal-jejunal bypass sleeve and an adjustable, totally implantable intragastric prosthesis, indicate that they may be viable options for obesity treatment. Other agents, such as botulinum toxin and a device known as the 'butterfly', are currently at the experimental stage.

CONCLUSION

New endoscopic methods for weight loss may be valuable in the treatment of obesity; however, more clinical experience and technical improvements are necessary before implementing their widespread use.

An update on less invasive and endoscopic techniques mimicking the effect of bariatric surgery

Obesity (BMI 30-35 kg/m(2)) and its associated disorders such as type 2 diabetes, nonalcoholic fatty liver disease, and cardiovascular disease have reached pandemic proportions worldwide. For the morbidly obese population (BMI 35-50 kg/m(2)), bariatric surgery has proven to be the most effective treatment to achieve significant and sustained weight loss, with concomitant positive effects on the metabolic syndrome. However, only a minor percentage of eligible candidates are treated by means of bariatric surgery. In addition, the expanding obesity epidemic consists mostly of relatively less obese patients who are not (yet) eligible for bariatric surgery. Hence, less invasive techniques and devices are rapidly being developed. These novel entities mimic several aspects of bariatric surgery either by gastric restriction (gastric balloons, gastric plication), by influencing gastric function (gastric botulinum injections, gastric pacing, and vagal nerve stimulation), or by partial exclusion of the small intestine (duodenal-jejunal sleeve). In the last decade, several novel less invasive techniques have been introduced and some have been abandoned again. The aim of this paper is to discuss the safety, efficacy, complications, reversibility, and long-term results of these latest developments in the treatment of obesity.

Natural orifice transluminal endoscopic surgery: New minimally invasive surgery come of age

Although in the past two decades, laparoscopic surgery, considered as a great revolution in the minimally invasive surgery field, has undergone major development worldwide, another dramatic surgical revolution has quietly appeared in recent years. Ever since Kalloo’s first report on transgastric peritoneoscopy in a porcine model in 2004, interest in a new surgical procedure named natural orifice transluminal endoscopic surgery (NOTES) has blossomed worldwide. Considering that a NOTES procedure could theoretically avoid any abdominal incision, operation-related pain and scarring, many surgeons and endoscopists have been enthusiastic in their study of this new technique. In recent years, several NOTES studies have been carried out on porcine models and even on humans, including transvaginal cholecystectomy, transgastric appendectomy, transvaginal appendectomy, and transvesical peritoneoscopy. So what is the current situation of NOTES and how many challenges do we still face? This review discusses the current research progress in NOTES.

Botulinum neurotoxin-A does not spread to distant muscles after intragastric injection: A double-blind single-fiber electromyography study

The purpose of this study was to perform a careful neurophysiological examination to identify subclinical signs of botulinum toxin spread distant to the injection site following intragastric injection for obesity treatment. Single-fiber electromyography of extensor digitorum communis and repetitive stimulation of abductor digiti minimi were performed before and 8 days after multiple intragastric injections of botulinum toxin A (Botox, 200 U per patient) or placebo. The study was performed in a randomized double-blind fashion. No patient in either group displayed results indicative of neuromuscular dysfunction either before or after the treatment. No significant change in muscle jitter was observed when comparing baseline with the after-treatment evaluation in either group, and no significant differences between groups were observed. After intragastric botulinum toxin injection no subclinical sign of distant spread was observed.

A multicenter, randomized efficacy study of the EndoBarrier Gastrointestinal Liner for presurgical weight loss prior to bariatric surgery

BACKGROUND

The endoscopically placed duodenal-jejunal bypass sleeve or EndoBarrier Gastrointestinal Liner has been designed to achieve weight loss in morbidly obese patients. We report on the first European experience with this device.

METHODS

A multicenter, randomized clinical trial was performed. Forty-one patients were included and 30 underwent sleeve implantation. Eleven patients served as a diet control group. All patients followed the same low-calorie diet during the study period. The purpose of the study was to determine the safety and efficacy of the device.

RESULTS

Twenty-six devices were successfully implanted. In 4 patients, implantation could not be achieved. Four devices were explanted prior to the initial protocol end point because of migration (1), dislocation of the anchor (1), sleeve obstruction (1), and continuous epigastric pain (1). The remaining patients all completed the study. Mean procedure time was 35 minutes (range: 12-102 minutes) for a successful implantation and 17 minutes (range: 5-99 minutes) for explantation. There were no procedure related adverse events. During the study period the 26 duodenal-jejunal bypass sleeve patients (100%) had at least one adverse event, mainly abdominal pain and nausea during the first week after implantation. Initial mean body mass index (BMI, kg/m2) was 48.9 and 47.4 kg/m2 for the device and control patients, respectively. Mean excess weight loss after 3 months was 19.0% for device patients versus 6.9% for control patients (P < 0.002). Absolute change in BMI at 3 months was 5.5 and 1.9 kg/m2, respectively. Type 2 diabetes mellitus was present at baseline in 8 patients of the device group and improved in 7 patients during the study period (lower glucose levels, HbA1c, and medication requirements).

CONCLUSION

The EndoBarrier Gastrointestinal Liner is a feasible and safe noninvasive device with excellent short-term weight loss results. The device also has a significant positive effect on type 2 diabetes mellitus. Long-term randomized and sham studies for weight loss and treatment of diabetes are necessary to determine the role of the device in the treatment of morbid obesity.This study was registered at www.clinicaltrials.gov (registration number: NCT00830440).

Endoscopic interventions for weight loss surgery

In this paper we review the state-of-the-art in endoscopic interventions for obesity treatment and make best practice recommendations for weight loss surgery (WLS). We performed a systematic search of English-language literature published between April 2004 and June 2008 in MEDLINE and the Cochrane Library on WLS and endoscopic interventions, endoscopically placed devices, minimally invasive surgery, image-guided surgery, endoluminal surgery, endoscopic instrumentation, interventional gastroenterology, transluminal surgery, and natural orifice transluminal surgery. We also searched the literature on endoscopic interventions and WLS and patient safety. We identified 36 pertinent articles, all of which were reviewed in detail; assessed the current science in endoscopic interventions for WLS; and made best practice recommendations based on the latest available evidence. Our findings indicate that endoscopic interventions and endoscopically placed devices may provide valuable approaches to the management of WLS complications and the primary management of obesity. Given the rapid changes in endoscopic technologies and techniques, systematic literature review is required to address issues related to the emerging role of endoluminal surgery in the treatment of obesity. These interventions should be a high priority for development and investigation.

Effects of intramural administration of Botulinum Toxin A on gastric emptying and eating capacity in obese patients

BACKGROUND

Intraparietal gastric administration of Botulinum Toxin A has been studied in open trials to induce satiety and increase weight loss of obese patients with contradictory results. In previous studies only the antrum was the target for Botulinum Toxin A, whereas the fundus, which exerts important activity on gastric accommodation, was excluded. In this study we report the effects of injection into both gastric regions on solid gastric capacity and emptying of the stomach.

MATERIALS AND METHODS

In this study we extended our previous investigations to include 30 obese patients who received Botulinum Toxin A (120 U into the antrum and 80 U into the fundus) or saline by intraparietal endoscopic injection. The two groups were homogeneous for age, gender, body weight and body mass index. Body weight and body mass index, solid gastric emptying (T(1/2) and T(lag) at the octanoic acid breath test) and maximal gastric capacity for solids (kcal) were determined before injection and 2 months later. The results were expressed as mean values (S.E.M.). t-Test or Wilcoxon test was used for statistical analysis, p<0.05 being considered significant.

RESULTS

Both treatments induced a significant reduction of body weight and body mass index but Botulinum Toxin A exerted a significantly greater effect (body weight -11.8+/-0.9 kg vs. -5.5+/-1.1 kg, p<0.0002; body mass index -4.1+/-0.2 vs. -2.2+/-0.4, p<0.001). The maximal gastric capacity for solids was also reduced by both Botulinum Toxin A and placebo, the former being significantly more effective (679+/-114 kcal vs. 237+/-94 kcal, p<0.008). Botulinum Toxin A also significantly increased T(1/2) from 83.4+/-3.9 to 101.6+/-9.9 min, p<0.03) but T(lag) was unchanged. Placebo had no effect on either of these parameters.

CONCLUSIONS

Our results demonstrated that Botulinum Toxin A makes weight loss easier in obese patients. It acts by increasing the solid gastric emptying time and reducing the solid eating capacity of the stomach.