Preoperative Micronutrient Repletion Strategies in Metabolic and Bariatric Surgery: A Systematic Review

BACKGROUND

Evidence is lacking to inform how micronutrient deficiencies should be prevented and treated before metabolic-bariatric surgery to optimize patient outcomes.

OBJECTIVE

This systematic review aimed to examine the effect of preoperative repletion strategies for micronutrient deficiencies on micronutrient biochemistry, quality of life, and complication rates among candidates for metabolic and bariatric surgery compared with usual care, alternate strategies, or no treatment.

METHODS

PubMed, Embase, CINAHL, and CENTRAL was searched in April 2024. A grey literature search was updated in April 2024 via Google search. Eligible observational and interventional studies were those that provided micronutrient repletion before the surgery and measured micronutrient status pre- and/or postsurgery. Studies with participants who were pregnant, lactating, or elected jejunocolic bypass, jejunoileal bypass, vertical banded gastroplasty, and biliopancreatic diversion were excluded. Risk of bias was assessed using the Academy of Nutrition and Dietetics Quality Criteria Checklist. Findings were narratively synthesized and the Grading of Recommendation, Assessment, Development and Evaluations was adopted when applicable. Twenty studies (n = 27 groups) were included (n = 15 observational; n = 5 interventional).

RESULTS

Strategies targeted vitamins A, D, E, B6, B12, C, thiamin, folate, calcium, iron, selenium, and zinc, including chronic dosing of oral supplements and multivitamins (n = 21), megadoses of oral supplements (n = 1), intramuscular injection (n = 1), intravenous infusion (n = 1), and a mix of injection and oral supplements (n = 3). Preoperative repletion strategies varied in efficacy. Chronic dosing of oral supplements increased vitamin D levels (n = 4 interventional studies; Grading of Recommendation, Assessment, Development and Evaluations rating: moderate). Multivitamins did not improve vitamin B12 status but improved status of vitamin B6, vitamin C, and folate. Iron infusion (n = 1) increased ferritin levels, despite small sample size and low adherence rate, whereas oral iron supplementation resulted in unchanged (n = 4) or decreased (n = 1) ferritin levels.

CONCLUSIONS

Proactive and personalized micronutrient repletion schedules may decrease the risk of preoperative and early postoperative deficiency.

A Comparison of the Health Benefits of Customized Multivitamins and Standard Supplementation Post-bariatric Surgery: A Systematic Review

Rates of obesity increase worldwide year after year. This review explored if customized multivitamins (CMV) resulted in less micronutrient deficiency and higher serum levels of vitamins and minerals when compared to standard multivitamins (SMV) post-bariatric surgery in adults. Vitamins investigated were vitamins B1, B6, B12, D, parathyroid hormone (PTH), calcium, iron, hemoglobin, ferritin, folic acid, zinc, and magnesium. In Roux-en-Y gastric bypass (RYGB) patients weight loss surgeries (WLS) Forte or chewable CMV were studied, while in sleeve gastrectomy (SG) patients, WLS Optimum 1.0 (Opt. 1.0) or WLS Optimum 2.0 (Opt. 2.0) multivitamins were studied. An electronic search was performed on three databases (PubMed (n=28), Embase (n=120), and Cochrane (n=106)) to identify clinical trials and cohort studies. The inclusion criteria focused on studies since 2011 for adults ≥18 years old post-GB and SG. The keywords included bypass, sleeve, WLS, and multivitamins. Four clinical trials and three cohort studies were included. Jadad Scale was used to assess the quality and the bias risk in the clinical trials and the Newcastle-Ottawa scale (NOS) was used for the cohort studies. The PICO model and PRISMA rules were followed, where the outcomes targeted certain vitamin serum levels and the levels of deficiencies. The results of WLS Forte were better than SMV. The chewable CMV and Opt. 1.0 results were comparable to SMV. Opt. 2.0 was slightly better than Opt. 1.0. Further modifications would enhance the CMV presented in this systemic review. SMV would still be recommended until CMV are modified and tested. Multi-center trials that monitor the effect of the modified CMV on the serum levels of vitamins and minerals in the longer term in different wider populations are needed.

Difference in 30-Day Readmission Rates After Laparoscopic Sleeve Gastrectomy Versus Laparoscopic Roux-En-Y Gastric Bypass: a Propensity Score Matched Study Using ACS NSQIP Data (2015-2019)

PURPOSE

There are very few studies that have compared the short-term outcomes of laparoscopic Roux-en-Y gastric bypass (LRYGB) and laparoscopic sleeve gastrectomy (LSG). Among short-term outcomes, hospital readmission after these procedures is an area for quality enhancement and cost reduction. In this study, we compared 30-day readmission rates after LSG and LRYGB through analyzing a nationalized dataset. In addition, we identified the reasons of readmission.

MATERIALS AND METHODS

The current study was a retrospective analysis of data from National Surgical Quality Improvement Program (NSQIP) All adult patients, ≥ 18 years of age and who had LSG or LRYGB during 2014 to 2019 were included. Current Procedural Terminology (CPT) codes were used to identify the procedures. Multivariate logistic regressions were used to calculate propensity score adjusted odds ratios (ORs) for all cause 30-day re-admissions.

RESULTS

There were 109,900 patients who underwent laparoscopic bariatric surgeries (67.5% LSG and 32.5% LRYGB). Readmissions were reported in 4168 (3.8%) of the patients and were more common among RYGB recipients compared to LSG (5.6% versus 2.9%, P < 0.001). The odds of 30-day readmissions were significantly higher among LRYGB group compared to LSG group (AOR, 2.20; 95% CI; 1.83, 2.64). In addition, variables such as age, chronic obstructive pulmonary disease, hypertension, bleeding disorders, blood urea nitrogen, SGOT, alkaline phosphatase, hematocrit, and operation time were significantly predicting readmission rates.

CONCLUSIONS

Readmission rates were significantly higher among those receiving LRYGB, compared to LSG. Readmission was also affected by many patient factors. The factors could help patients and providers to make informed decisions for selecting appropriate procedures.

Exploring microRNAs as predictive biomarkers for type 2 diabetes mellitus remission after sleeve gastrectomy: A pilot study

OBJECTIVE

This study aimed to evaluate microRNAs (miRNAs) as predictive biomarkers for type 2 diabetes (T2D) remission 12 months after sleeve gastrectomy (SG).

METHODS

A total of 179 serum miRNAs were profiled, and 26 clinical variables were collected from 46 patients. Two patients were later excluded because of hemolysis, and six patients with unclear remission status were set aside to evaluate the prediction models. The remaining 38 patients were included for model building. Variable selection was done using different approaches, including Least Absolute Shrinkage and Selection Operator (LASSO). Prediction models were then developed using LASSO and assessed in the validation set.

RESULTS

A total of 26 out of 38 patients achieved T2D remission 12 months after SG. The prediction model with only clinical variables misclassified two patients, which were correctly classified using miRNAs. Two miRNA-only models achieved an accuracy of one but performed poorly for the validation set. The best miRNA model was a mixed model (accuracy: 0.974) containing four miRNAs (hsa-miR-32-5p, hsa-miR-382-5p, hsa-miR-1-3p, and hsa-miR-21-5p) and four clinical variables (T2D medication, sex, age, and fasting blood glucose). These miRNAs are involved in pathways related to obesity and insulin resistance.

CONCLUSIONS

This study suggests that four serum miRNAs might be predictive biomarkers for T2D remission 12 months after SG, but further validation studies are needed.

The hamster wheel: a case study on embodied narrative identity and overcoming severe obesity

Based in narrative phenomenology, this article describes an example of how lived time, self and bodily engagement with the social world intertwine, and how our sense of self develops. We explore this through the life story of a woman who lost weight through surgery in the 1970 s and has fought against her own body, food and eating ever since. Our narrative analysis of interviews, reflective notes and email correspondence disentangled two storylines illuminating paradoxes within this long-term weight loss process. Thea's Medical Weight Narrative: From Severely Obese Child to Healthy Adult is her story in context of medicine and obesity treatment and expresses success and control. Thea's Story: The Narrative of Fighting Weight is the experiential story, including concrete examples and quotes, highlighting bodily struggles and the inescapable ambiguity of being and having one's body. The two storylines coexist and illuminate paradoxes within the weight loss surgery narrative, connected to meaningful life events and experiences, eating practices and relationships with important others. Surgery was experienced as lifesaving, yet the surgical transformation did not suffice, because it did not influence appetite or, desire for food in the long run. In the medical narrative of transforming the body by repair, a problematic relationship with food did not fit into the plot.

Improving Outcomes of Bariatric Surgery in Patients With Cirrhosis in the United States: A Nationwide Assessment

INTRODUCTION

With increasing burden of obesity and liver disease in the United States, a better understanding of bariatric surgery in context of cirrhosis is needed. We described trends of hospital-based outcomes of bariatric surgery among cirrhotics and determined effect of volume status and type of surgery on these outcomes.

METHODS

In this population-based study, admissions for bariatric surgery were extracted from the National Inpatient Sample using International Classification of Diseases, 9th and 10th Revision, Clinical Modification codes from 2004 to 2016 and grouped by cirrhosis status, type of bariatric surgery, and center volume. In-hospital mortality, complications, and their trends were compared between these groups using weighted counts, odds ratios [ORs], and logistic regression.

RESULTS

Among 1,679,828 admissions for bariatric surgery, 9,802 (0.58%) had cirrhosis. Cirrhosis admissions were more likely to be in white men, had higher Elixhauser Index, and higher in-hospital complications rates including death (1.81% vs 0.17%), acute kidney injury (4.5% vs 1.2%), bleeding (2.9% vs 1.1%), and operative complications (2% vs 0.6%) (P < 0.001 for all) compared to those without cirrhosis. Overtime, restrictive surgeries have grown in number (12%-71%) and complications rates have trended down in both groups. Cirrhotics undergoing bariatric surgery at low-volume centers (<50 procedures per year) and nonrestrictive surgery had a higher inpatient mortality rate (adjusted OR 4.50, 95% confidence interval 3.14-6.45, adjusted OR 4.00, 95% confidence interval 2.68-5.97, respectively).

DISCUSSION

Contemporary data indicate that among admissions for bariatric surgery, there is a shift to restrictive-type surgeries with an improvement in-hospital complications and mortality. However, patients with cirrhosis especially those at low-volume centers have significantly higher risk of worse outcomes (see Visual abstract, Supplementary Digital Content, http://links.lww.com/AJG/B648).

From the Knife to the Endoscope-a History of Bariatric Surgery

PURPOSE OF REVIEW

Current bariatric surgical practice has developed from early procedures, some of which are no longer routinely performed. This review highlights how surgical practice in this area has developed over time.

RECENT FINDINGS

This review outlines early procedures including jejuno-colic and jejuno-ileal bypass, initial experience with gastric bypass, vertical banded gastroplasty and biliopancreatic diversion with or without duodenal switch. The role laparoscopy has played in the widespread utilization of surgery for treatment of obesity will be described, as will the development of procedures which form the mainstay of current bariatric surgical practice including gastric bypass, sleeve gastrectomy and adjustable gastric banding. Endoscopic therapies for the treatment of obesity will be described. By outlining how bariatric surgical practice has developed over time, this review will help practicing surgeons understand how individual procedures have evolved and also provide insight into potential future developments in this field.

Laparoscopic Sleeve Gastrectomy Is Associated with Lower 30-Day Morbidity Versus Laparoscopic Gastric Bypass: an Analysis of the American College of Surgeons NSQIP

PURPOSE

Laparoscopic sleeve gastrectomy (LSG) has rapidly gained popularity as a single-stage operation for the treatment of morbid obesity, as patients undergoing LSG have been shown to achieve similar weight loss and resolution of obesity-related comorbidities in comparison to those undergoing Roux-en-Y gastric bypass (RYGB), the "gold standard" bariatric operation. Although LSG poses fewer technical challenges than RYGB, little is known about differences in short-term outcomes among patients undergoing LSG and RYGB. We hypothesized that LSG is associated with lower 30-day risk-adjusted serious morbidity.

METHODS

Preoperative characteristics and 30-day outcomes from the American College of Surgeons National Surgical Quality Improvement Program (ACSNSQIP) Participant Use Files (PUF) 2010-2014 were selected for all patients who underwent LSG or RYGB. Descriptive comparisons were performed using chi-square and Wilcoxon's rank-sum tests as appropriate. The primary outcome was a risk-adjusted composite measure of 30-day serious morbidity and mortality.

RESULTS

We analyzed records for 47,982 (42.0%) and 66,380 (58.0%) patients undergoing LSG and RYGB, respectively. On univariate analysis, LSG patients had a lower rate of organ space infection (0.45% vs. 0.68%, p < 0.001), lower rate of bleeding requiring transfusions (1.00% vs. 1.60%, p < 0.001), lower rate of sepsis (0.34% vs. 0.49%, p < 0.001), and septic shock (0.12% vs. 0.22%, p < 0.001) and required fewer unplanned reoperations (1.34% vs. 2.56%, p < 0.001) than RYGB patients. Both groups had similar rates of deep venous thrombosis (0.33% vs. 0.28%, p = 0.15) and pulmonary embolism (0.17% vs. 0.21%, p = 0.15). Mortality was lower among LSG patients (0.09% vs. 0.14%, p = 0.01). On multivariate analysis, RYGB was associated with higher risk-adjusted 30-day serious morbidity than LSG (odds ratio 1.61; 95% CI 1.52-1.71, p < 0.001). Older age, female gender, higher BMI, and insulin-dependent diabetes were also associated with risk of serious morbidity (C-statistic = 0.60).

CONCLUSION

Serious morbidity following bariatric surgery is uncommon; however, LSG may be associated with modest protection from adverse 30-day outcomes in comparison to RYGB. Our conclusion is limited by the difference in baseline risk factors of the populations studied.

The Effects of Bariatric Surgery on Islet Function, Insulin Secretion, and Glucose Control

Although bariatric surgery was developed primarily to treat morbid obesity, evidence from the earliest clinical observations to the most recent clinical trials consistently demonstrates that these procedures have substantial effects on glucose metabolism. A large base of research indicates that bariatric surgeries such as Roux-en-Y gastric bypass (RYGB), vertical sleeve gastrectomy (VSG), and biliopancreatic diversion (BPD) improve diabetes in most patients, with effects frequently evident prior to substantial weight reduction. There is now unequivocal evidence from randomized controlled trials that the efficacy of surgery is superior to intensive life-style/medical management. Despite advances in the clinical understanding and application of bariatric surgery, there remains only limited knowledge of the mechanisms by which these procedures confer such large changes to metabolic physiology. The improvement of insulin sensitivity that occurs with weight loss (e.g., the result of diet, illness, physical training) also accompanies bariatric surgery. However, there is evidence to support specific effects of surgery on insulin clearance, hepatic glucose production, and islet function. Understanding the mechanisms by which surgery affects these parameters of glucose regulation has the potential to identify new targets for therapeutic discovery. Studies to distinguish among bariatric surgeries on key parameters of glucose metabolism are limited but would be of considerable value to assist clinicians in selecting specific procedures and investigators in delineating the resulting physiology. This review is based on literature related to factors governing glucose metabolism and insulin secretion after the commonly used RYGB and VSG, and the less frequently used BPD and adjustable gastric banding.

Remission of Type 2 Diabetes Mellitus after Bariatric Surgery: Fact or Fiction?

Although type 2 diabetes mellitus (T2DM) has been traditionally viewed as an intractable chronic medical condition, accumulating evidence points towards the notion that a complete remission of T2DM is feasible following a choice of medical and/or surgical interventions. This has been paralleled by increasing interest in the establishment of a universal definition for T2DM remission which, under given circumstances, could be considered equivalent to a “cure”. The efficacy of bariatric surgery in particular for achieving glycemic control has highlighted surgery as a candidate curative intervention for T2DM. Herein, available evidence regarding available surgical modalities and the mechanisms that drive metabolic amelioration after bariatric surgery are reviewed. Furthermore, reports from observational and randomized studies with regard to T2DM remission are reviewed, along with concepts relevant to the variety of definitions used for T2DM remission and other potential sources of discrepancy in success rates among different studies.

Meta-Analysis of Differential miRNA Expression after Bariatric Surgery

Bariatric surgery is an efficient treatment for weight loss in obese patients and for resolving obesity comorbidities. However, the mechanisms behind these outcomes are unclear. Recent studies have indicated significant alterations in the transcriptome after surgery, specifically in the differential expression of microRNAs. In order to summarize the recent findings, we conducted a systematic summary of studies comparing microRNA expression levels before and after surgery. We identified 17 animal model and human studies from four databases (Ovid, Scopus, Web of Science, and PubMed) to be enrolled in this meta-analysis. From these studies, we identified 14 miRNAs which had the same direction of modulation of their expression after surgery in at least two studies (downregulated: hsa-miR-93-5p, hsa-miR-106b-5p, hsa-let-7b-5p, hsa-let-7i-5p, hsa-miR-16-5p, hsa-miR-19b-3p, hsa-miR-92a-3p, hsa-miR-222-3p, hsa-miR-142-3p, hsa-miR-140-5p, hsa-miR-155-5p, rno-miR-320-3p; upregulated: hsa-miR-7-5p, hsa-miR-320c). Pathway analysis for these miRNAs was done using database resources (DIANA-TarBase and KEGG pathway database) and their predicted target genes were discussed in relation with obesity and its comorbidities. Discrepancies in study design, such as miRNA source, bariatric surgery type, time of observation after surgery, and miRNA profiling methods, were also discussed.

Laparoscopic Gastric Plication versus Laparoscopic Sleeve Gastrectomy: An Up-to-Date Systematic Review and Meta-Analysis

Introduction

A meta-analysis was conducted in order to provide an up-to-date comparison of laparoscopic sleeve gastrectomy (LSG) and laparoscopic gastric plication (LGP) for morbid obesity.

Materials and Methods

The PRISMA guidelines and the Cochrane Handbook for Systematic Reviews of Interventions were used for the conduction of this study. A systematic literature search was performed in the electronic databases (MEDLINE, CENTRAL, and Web of Science and Scopus). The fixed effects or random effects model was used according to the Cochran Q test.

Results

Totally, 12 eligible studies were extracted. LSG displayed a statistically significant lower rate of overall complications (OR: 0.35; 95% CI: 0.17, 0.68; p=0.002) and a sustainable higher %EWL through all time endpoints (OR: 4.86, p=0.04; OR: 7.57, p < 0.00001; and OR: 13.74; p < 0.00001). There was no difference between the two techniques in terms of length of hospital stay (p=0.16), operative duration (p=0.81), reoperation rate (p=0.51), and cost (p=0.06).

Conclusions

LSG was demonstrated to have a lower overall complications and a higher weight loss rate, when compared to LGP. Further RCTs of a higher methodological quality level, with a larger sample size, are required in order to validate these findings.

The history of metabolic and bariatric surgery: Development of standards for patient safety and efficacy

Weight loss surgery, also referred to as bariatric surgery, has been in existence since the 1950's. Over the decades, it has been demonstrated to successfully achieve meaningful and sustainable weight loss in a large number of patients who undergo these procedures. Additionally, the benefits observed across a number of metabolic disorders such as type 2 diabetes mellitus and hyperlipidemia, are often to a degree, independent of the weight loss, thus the term "metabolic bariatric surgery (MBS)" has become a better descriptor. Throughout its long history, MBS has evolved from an era of high morbidity and mortality to one of laudable safety despite the high-risk nature of the patients undergoing these major gastrointestinal procedures. This article will describe the historic evolution of MBS and concentrate on those events that were instrumental in reducing the morbidity of these operations.

Liver Transplantation and Bariatric Surgery: Best Approach

Obesity has become increasingly prevalent, and the number of obese patients in need of liver transplant is expected to continue to increase. In addition, liver disease due to nonalcoholic fatty liver disease is expected to become the leading cause of liver transplantation in the near future. However, obesity remains a relative contraindication in liver transplant. New strategies in managing this patient population are clearly needed. To this end, the authors review the current literature on the efficacy of bariatric surgery in the setting of liver transplantation in obese patients.

Changing tastes: learning hunger and fullness after gastric bypass surgery

Gastric bypass surgery is a specific medical technology that alters the body in ways that force patients to fundamentally change their eating habits. When patients enrol for surgery, they enter a learning process, encountering new and at times contested ways of sensing their bodies, tasting, and experiencing hunger and fullness. In this paper, we explore how patients begin to eat again after gastric bypass surgery. The empirical data used here are drawn from a Danish fieldwork study of individuals undergoing obesity surgery. The material presented shows how the patients used instructions on how to eat. We explore the ways in which diverse new experiences and practices of hunger and fullness are part of the process of undergoing surgery for severe obesity. New sensory experiences lead to uncertainty; as a result, patients practice what we term mimetic eating, which reflects a 'sensory displacement' and hence a rupture in the person's sense of self and social relations. We suggest that eating should be conceptualised as a practice that extends beyond the boundaries of our bodies and into diverse realms of relations and practices, and that changing the way we eat also changes the fundamentally embodied experience of who we are.

The experience of regaining weight following weight loss surgery: A narrative-phenomenological exploration

Weight loss surgery (WLS) is gaining ground as the most effective treatment against obesity. In the literature, however, we see a divide among individuals who have undergone WLS based on the amount of weight lost and maintained: successful and unsuccessful patients. In this article, we focus on the notion of unsuccessful patients-exploring the accounts of three women who have regained weight following WLS. In doing so, we endeavor to better understand how weight regain has meaning, and its impact and implications for the lives of individuals who undergo WLS. The findings reveal how weight-regain stories are easily silenced, buried beneath social, cultural, and institutional/medical narratives of successful weight loss and transformation. People who have such experiences may feel reticent to reveal them and in doing so increase their own suffering, therefore leaving the popular narratives unchallenged.

A review of the role of robotics in bariatric surgery

The epidemic of obesity continues to be a major health issue. It is now almost uniform that surgical procedures for weight loss are performed with minimally invasive techniques. This article reviews the literature regarding obesity-related health issues, in particular risk of malignancy, and the application of robotic technology in weight loss surgical procedures. With increasing literature and technology in surgical robotics, its application in the field of bariatric surgery continues to evolve.

Mechanisms underlying weight loss and metabolic improvements in rodent models of bariatric surgery

Obesity is a growing health risk with few successful treatment options and fewer still that target both obesity and obesity-associated comorbidities. Despite ongoing scientific efforts, the most effective treatment option to date was not developed from basic research but by surgeons observing outcomes in the clinic. Bariatric surgery is the most successful treatment for significant weight loss, resolution of type 2 diabetes and the prevention of future weight gain. Recent work with animal models has shed considerable light on the molecular underpinnings of the potent effects of these 'metabolic' surgical procedures. Here we review data from animal models and how these studies have evolved our understanding of the critical signalling systems that mediate the effects of bariatric surgery. These insights could lead to alternative therapies able to accomplish effects similar to bariatric surgery in a less invasive manner.

Re-embodying eating: patients' experiences 5 years after bariatric surgery

Health experts advise and expect patients to eat healthily after bariatric surgery. For patients, difficulties with eating might have been a long-standing, problematic part of life-a part that is not necessarily healed by surgery. Empirical research on patients' experiences of eating practices after bariatric surgery is lacking. Aiming to contribute to the development of clinical practice, we explored meanings attached to eating in the long term and sought descriptions of change and bodily sensations. We interviewed 14 patients at least 5 years after bariatric surgery. The surgical restriction forced changes in the way patients sensed their own body in eating, but the uncertainty related to maintaining weight loss in the long term remained. Meanings attached to eating transcended food as choices situated in a nourishment and health perspective, and were not necessarily changed. Eating was an existential and embodied practice, which remained an ambiguous and sensitive matter after surgery.

Lifestyle management for enhancing outcomes after bariatric surgery

Bariatric surgery has been safe and effective for treatment of severe obesity and comorbidities like type 2 diabetes mellitus (T2D). Nonetheless, weight loss and health outcomes vary considerably across individuals. Although the factors associated with outcomes are not fully understood, postoperative weight loss following any type of bariatric surgery is largely dependent on the extent to which patients can make and sustain changes in eating and activity. Therefore, lifestyle management including diet, exercise, and behavior modification is critical to helping patients achieve long-term weight loss. Pharmacotherapy and reoperation may also play a role after bariatric surgery. In this article, we highlight recent research findings in all of these areas to provide suggestions for how to enhance outcomes following bariatric surgery. Research on the mechanisms for weight loss and improvements in T2D following the different surgical procedures is needed to support the development of more personalized approaches to the multidisciplinary management of severe obesity.

Surgery for weight loss in adults

BACKGROUND

Bariatric (weight loss) surgery for obesity is considered when other treatments have failed. The effects of the available bariatric procedures compared with medical management and with each other are uncertain. This is an update of a Cochrane review first published in 2003 and most recently updated in 2009.

OBJECTIVES

To assess the effects of bariatric surgery for overweight and obesity, including the control of comorbidities.

SEARCH METHODS

Studies were obtained from searches of numerous databases, supplemented with searches of reference lists and consultation with experts in obesity research. Date of last search was November 2013.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing surgical interventions with non-surgical management of obesity or overweight or comparing different surgical procedures.

DATA COLLECTION AND ANALYSIS

Data were extracted by one review author and checked by a second review author. Two review authors independently assessed risk of bias and evaluated overall study quality utilising the GRADE instrument.

MAIN RESULTS

Twenty-two trials with 1798 participants were included; sample sizes ranged from 15 to 250. Most studies followed participants for 12, 24 or 36 months; the longest follow-up was 10 years. The risk of bias across all domains of most trials was uncertain; just one was judged to have adequate allocation concealment.All seven RCTs comparing surgery with non-surgical interventions found benefits of surgery on measures of weight change at one to two years follow-up. Improvements for some aspects of health-related quality of life (QoL) (two RCTs) and diabetes (five RCTs) were also found. The overall quality of the evidence was moderate. Five studies reported data on mortality, no deaths occurred. Serious adverse events (SAEs) were reported in four studies and ranged from 0% to 37% in the surgery groups and 0% to 25% in the no surgery groups. Between 2% and 13% of participants required reoperations in the five studies that reported these data.Three RCTs found that laparoscopic Roux-en-Y gastric bypass (L)(RYGB) achieved significantly greater weight loss and body mass index (BMI) reduction up to five years after surgery compared with laparoscopic adjustable gastric banding (LAGB). Mean end-of-study BMI was lower following LRYGB compared with LAGB: mean difference (MD) -5.2 kg/m² (95% confidence interval (CI) -6.4 to -4.0; P < 0.00001; 265 participants; 3 trials; moderate quality evidence). Evidence for QoL and comorbidities was very low quality. The LRGYB procedure resulted in greater duration of hospitalisation in two RCTs (4/3.1 versus 2/1.5 days) and a greater number of late major complications (26.1% versus 11.6%) in one RCT. In one RCT the LAGB required high rates of reoperation for band removal (9 patients, 40.9%).Open RYGB, LRYGB and laparoscopic sleeve gastrectomy (LSG) led to losses of weight and/or BMI but there was no consistent picture as to which procedure was better or worse in the seven included trials. MD was -0.2 kg/m² (95% CI -1.8 to 1.3); 353 participants; 6 trials; low quality evidence) in favour of LRYGB.  No statistically significant differences in QoL were found (one RCT). Six RCTs reported mortality; one death occurred following LRYGB. SAEs were reported by one RCT and were higher in the LRYGB group (4.5%) than the LSG group (0.9%). Reoperations ranged from 6.7% to 24% in the LRYGB group and 3.3% to 34% in the LSG group. Effects on comorbidities, complications and additional surgical procedures were neutral, except gastro-oesophageal reflux disease improved following LRYGB (one RCT). One RCT of people with a BMI 25 to 35 and type 2 diabetes found laparoscopic mini-gastric bypass resulted in greater weight loss and improvement of diabetes compared with LSG, and had similar levels of complications.Two RCTs found that biliopancreatic diversion with duodenal switch (BDDS) resulted in greater weight loss than RYGB in morbidly obese patients. End-of-study mean BMI loss was greater following BDDS: MD -7.3 kg/m² (95% CI -9.3 to -5.4); P < 0.00001; 107 participants; 2 trials; moderate quality evidence). QoL was similar on most domains. In one study between 82% to 100% of participants with diabetes had a HbA1c of less than 5% three years after surgery. Reoperations were higher in the BDDS group (16.1% to 27.6%) than the LRYGB group (4.3% to 8.3%). One death occurred in the BDDS group.One RCT comparing laparoscopic duodenojejunal bypass with sleeve gastrectomy versus LRYGB found BMI, excess weight loss, and rates of remission of diabetes and hypertension were similar at 12 months follow-up (very low quality evidence). QoL, SAEs and reoperation rates were not reported. No deaths occurred in either group.One RCT comparing laparoscopic isolated sleeve gastrectomy (LISG) versus LAGB found greater improvement in weight-loss outcomes following LISG at three years follow-up (very low quality evidence). QoL, mortality and SAEs were not reported. Reoperations occurred in 20% of the LAGB group and in 10% of the LISG group.One RCT (unpublished) comparing laparoscopic gastric imbrication with LSG found no statistically significant difference in weight loss between groups (very low quality evidence).  QoL and comorbidities were not reported. No deaths occurred. Two participants in the gastric imbrication group required reoperation.

AUTHORS' CONCLUSIONS

Surgery results in greater improvement in weight loss outcomes and weight associated comorbidities compared with non-surgical interventions, regardless of the type of procedures used. When compared with each other, certain procedures resulted in greater weight loss and improvements in comorbidities than others. Outcomes were similar between RYGB and sleeve gastrectomy, and both of these procedures had better outcomes than adjustable gastric banding. For people with very high BMI, biliopancreatic diversion with duodenal switch resulted in greater weight loss than RYGB. Duodenojejunal bypass with sleeve gastrectomy and laparoscopic RYGB had similar outcomes, however this is based on one small trial. Isolated sleeve gastrectomy led to better weight-loss outcomes than adjustable gastric banding after three years follow-up. This was based on one trial only.  Weight-related outcomes were similar between laparoscopic gastric imbrication and laparoscopic sleeve gastrectomy in one trial. Across all studies adverse event rates and reoperation rates were generally poorly reported. Most trials followed participants for only one or two years, therefore the long-term effects of surgery remain unclear.

Laparoscopic sleeve gastrectomy for morbid obesity: 5-year results

BACKGROUND

Data concerning the long-term efficacy of laparoscopic sleeve gastrectomy in the treatment of morbid obesity remain scarce. In this retrospective, the authors present 5-year follow-up of 30 patients having undergone laparoscopic sleeve gastrectomy.

METHODS

Since 2004, 30 patients underwent laparoscopic sleeve gastrectomy and completed 5 years of follow-up. Five patients were subsequently subjected to laparoscopic Roux-en-Y gastric bypass and were excluded from further analysis. The remaining 25 patients comprised the study population.

RESULTS

Mean excess weight loss was 65.2 ± 6.1%, 64.7 ± 5.6%, 62 ± 4.9%, 58.2 ± 5.5%, and 56.4 ± 5.8% for the first 5 years, respectively. There were no deaths, nor any major morbidity. Remission of comorbidities was observed in 40% to 80.9% of cases.

CONCLUSIONS

Laparoscopic sleeve gastrectomy is a safe and effective means of treatment of morbid obesity both in the short and in the long term. More research is needed to better predict which patient will benefit most from this operation.

Enteroendocrine secretion of gut hormones in diabetes, obesity and after bariatric surgery

Gastric bypass surgery is associated with a major weight loss and often causes remission in patients with type 2 diabetes. Surgery is also associated with dramatic increases in the secretion of the gut hormones, glucagon-like peptide-1 (GLP-1) and peptide YY (PYY), both of which regulate appetite and food intake, while GLP-1 in addition functions as an incretin hormone, stimulating insulin secretion. It has been possible to probe the role of GLP-1 for the diabetes resolution after gastric bypass using a GLP-1 receptor antagonist, and it is clear that the enhanced beta cell sensitivity to glucose which underlies the enhanced insulin secretion in the patients after the operation depends critically on the increased GLP-1 secretion. Both hormones seem to contribute importantly to the reduction in food intake after bypass and, therefore, to the weight loss. Currently, there are no data to indicate that decreased secretion of the hormones is involved in the pathogenesis of obesity and/or diabetes, but impaired secretion generally observed in obesity (and hence also in diabetes) may contribute to the development. Because of these effects receptor agonists for both hormones are currently being developed for the treatment of obesity and diabetes.