Caloric intake capacity as measured by a standard nutrient drink test helps to predict weight loss after bariatric surgery

Preoperative Prediction of Body Mass Index of Patients with Type 2 Diabetes at 1 Year After Laparoscopic Sleeve Gastrectomy: Cross-Sectional Study

Background: Very few models predict weight loss among type 2 diabetes mellitus (T2D) patients after laparoscopic sleeve gastrectomy (LSG). This retrospective study undertook such a task. Materials and Methods: We identified all patients >18 years old with T2D who underwent primary LSG at our institution and had complete data. The training set comprised 107 patients operated upon during the period April 2011 to June 2014; the validation set comprised 134 patients operated upon during the successive chronological period, July 2014 to December 2015. Sex, age, presurgery BMI, T2D duration, number of T2D medications, insulin use, hypertension, and dyslipidemia were utilized as independent predictors of 1-year BMI. We employed regression analysis, and assessed the goodness of fit and "Residuals versus Fits" plot. Paired sample t-tests compared the observed and predicted BMI at 1 year. Results: The model comprised preoperative BMI (β = 0.757, P = 0.026) + age (β = 0.142, P < 0.0001) with adjusted R² of 0.581 (P < 0.0001), and goodness of fit showed an unbiased model with accurate prediction. The equation was: BMI value 1 year after LSG = 1.777 + 0.614 × presurgery BMI (kg/m²) +0.106 × age (years). For validation, the equation exhibited an adjusted R² 0.550 (P < 0.0001), and the goodness of fit indicated an unbiased model. The BMI predicted by the model fell within -3.78 BMI points to +2.42 points of the observed 1-year BMI. Pairwise difference between the mean 1-year observed and predicted BMI was not significant (-0.41 kg/m², P = 0.225). Conclusions: This predictive model estimates the BMI 1 year after LSG. The model comprises preoperative BMI and age. It allows the forecast of patients' BMI after surgery, hence setting realistic expectations which are critical for patient satisfaction after bariatric surgery. An attainable target motivates the patient to achieve it.

EAES rapid guideline: systematic review, network meta-analysis, CINeMA and GRADE assessment, and European consensus on bariatric surgery-extension 2022

BACKGROUND

The European Association for Endoscopic Surgery Bariatric Guidelines Group identified a gap in bariatric surgery recommendations with a structured, contextualized consideration of multiple bariatric interventions.

OBJECTIVE

To provide evidence-informed, transparent and trustworthy recommendations on the use of sleeve gastrectomy, Roux-en-Y gastric bypass, adjustable gastric banding, gastric plication, biliopancreatic diversion with duodenal switch, one anastomosis gastric bypass, and single anastomosis duodeno-ileal bypass with sleeve gastrectomy in patients with severe obesity and metabolic diseases. Only laparoscopic procedures in adults were considered.

METHODS

A European interdisciplinary panel including general surgeons, obesity physicians, anesthetists, a psychologist and a patient representative informed outcome importance and minimal important differences. We conducted a systematic review and frequentist fixed and random-effects network meta-analysis of randomized-controlled trials (RCTs) using the graph theory approach for each outcome. We calculated the odds ratio or the (standardized) mean differences with 95% confidence intervals for binary and continuous outcomes, respectively. We assessed the certainty of evidence using the CINeMA and GRADE methodologies. We considered the risk/benefit outcomes within a GRADE evidence to decision framework to arrive at recommendations, which were validated through an anonymous Delphi process of the panel.

RESULTS

We identified 43 records reporting on 24 RCTs. Most network information surrounded sleeve gastrectomy and Roux-en-Y gastric bypass. Under consideration of the certainty of the evidence and evidence to decision parameters, we suggest sleeve gastrectomy or laparoscopic Roux-en-Y gastric bypass over adjustable gastric banding, biliopancreatic diversion with duodenal switch and gastric plication for the management of severe obesity and associated metabolic diseases. One anastomosis gastric bypass and single anastomosis duodeno-ileal bypass with sleeve gastrectomy are suggested as alternatives, although evidence on benefits and harms, and specific selection criteria is limited compared to sleeve gastrectomy and Roux-en-Y gastric bypass. The guideline, with recommendations, evidence summaries and decision aids in user friendly formats can also be accessed in MAGICapp:  https://app.magicapp.org/#/guideline/Lpv2kE CONCLUSIONS: This rapid guideline provides evidence-informed, pertinent recommendations on the use of bariatric and metabolic surgery for the management of severe obesity and metabolic diseases. The guideline replaces relevant recommendations published in the EAES Bariatric Guidelines 2020.

The Universal Eating Monitor (UEM): objective assessment of food intake behavior in the laboratory setting

The Universal Eating Monitor was a term used to describe a device used in a laboratory setting that enabled investigators to measure, with the same instrument, the rate of eating either solids or liquids, hence the term “universal”. It consisted of an electronic balance placed in a false panel under a table cloth on which could be placed a food reservoir that contained either solid or liquefied food. The device was created in order to determine whether rates of eating differed in pattern between solid and liquid foods. An acceptable mixture of foods of identical composition that could be served as either solid or blended as a liquid was used to test the hypothesis that eating rate and intake were affected by physical composition. A best-fitting mathematical function (intake was quadratic function of time, with coefficients varying among foods used and experimental conditions), quantified intake rates. The device was used to test a variety of mechanisms underlying food intake control. Eating rates were linear when solid foods were used, but negatively accelerated with liquids. Overall, intake did not differ between solid and liquefied food of identical composition. Satiation on a calorie for calorie basis was different among foods, but physical composition interacted with energy density. Hormones and gastric distension were strong influences on food intake and rate of eating. Individuals with bulimia nervosa and binge eating disorder ate more than individuals without these disturbances. Intake in social and individual contexts was identical, but the rate of eating was slower when two individuals dined together. The eating monitor has been a useful instrument for elucidating controls of food intake and describing eating pathology.

Network Meta-Analysis of Metabolic Surgery Procedures for the Treatment of Obesity and Diabetes

BACKGROUND

Metabolic surgery is part of a well-established treatment intensification strategy for obesity and its related comorbidities including type 2 diabetes (T2DM). Roux-en-Y gastric bypass (RYGB), sleeve gastrectomy (SG) and one-anastomosis gastric bypass (OAGB) are the most commonly performed metabolic surgeries worldwide, but comparative efficacy is uncertain. This study employed network meta-analysis to compare weight loss, T2DM remission and perioperative complications in adults between RYGB, SG and OAGB.

METHODS

MEDLINE, EMBASE, trial registries were searched for randomised trials comparing RYGB, SG and OAGB. Study outcomes were excess weight loss (at 1, 2 and 3-5 years), trial-defined T2DM remission at any time point and perioperative complications.

RESULTS

Twenty randomised controlled trials were included involving 1803 patients investigating the three metabolic surgical interventions. RYGB was the index for comparison. The excess weight loss (EWL) demonstrated minor differences at 1 and 2 years, but no differences between interventions at 3-5 years. T2DM remission was more likely to occur with either RYGB or OAGB when compared to SG. Perioperative complications were higher with RYGB when compared to either SG or OAGB. Two-way analysis of EWL and T2DM remission against the risk of perioperative complications demonstrated OAGB was the most positive on this assessment at all time points.

CONCLUSION

OAGB offers comparable metabolic control through weight loss and T2DM remission to RYGB and SG whilst minimising perioperative complications. Registration number: CRD42020199779 (https:// www.crd.york.ac.uk/PROSPERO ).

Baseline Presence of NAFLD Predicts Weight Loss after Gastric Bypass Surgery for Morbid Obesity

Background. Bariatric surgery is a widely used treatment for morbid obesity. Prediction of postoperative weight loss currently relies on prediction models, which mostly overestimate patients’ weight loss. Data about the influence of Non-alcoholic fatty liver disease (NAFLD) on early postoperative weight loss are scarce. Methods. This prospective, single-center cohort study included 143 patients receiving laparoscopic gastric bypass surgery (One Anastomosis-Mini Gastric Bypass (OAGB-MGB) or Roux-en-Y Gastric Bypass (RYGB)). Liver biopsies were acquired at surgery. NAFLD activity score (NAS) assigned patients to “No NAFLD”, “NAFL” or “NASH”. Follow up data were collected at 3, 6 and 12 months. Results. In total, 49.7% of patients had NASH, while 41.3% had NAFL. Compared with the No NAFLD group, NAFL and NASH showed higher body-mass-index (BMI) at follow-up (6 months: 31.0 kg/m² vs. 36.8 kg/m² and 36.1 kg/m², 12 months: 27.0 kg/m² vs. 34.4 and 32.8 kg/m²) and lower percentage of total body weight loss (%TBWL): (6 months: 27.1% vs. 23.3% and 24.4%; 12 months: 38.5% vs. 30.1 and 32.6%). Linear regression of NAS points significantly predicts percentage of excessive weight loss (%EWL) after 6 months (Cologne-weight-loss-prediction-score). Conclusions. Histopathological presence of NAFLD might lead to inferior postoperative weight reduction after gastric bypass surgery. The mechanisms underlying this observation should be further studied.

Reliability and responsiveness of virtual portion size creation tasks: Influences of context, foods, and a bariatric surgical procedure

Food portion size influences energy intake and sustained high-energy intake often leads to obesity. Virtual portion creation tasks (VPCTs), in which a participant creates portions of food on a computer screen, predict intake in healthy individuals. The objective of this study was to determine whether portions created in VPCTs are stable over time (test-retest reliability) and responsive to factors known to influence food intake, such as eating contexts and food types, and to determine if virtual portions can predict weight loss. Patients with obesity scheduled for bariatric surgery (n = 29), and individuals with a normal BMI (18.5-24.9 kg/m2, controls, n = 29), were instructed to create virtual portions of eight snack foods, which varied in energy density (low and high) and taste (sweet and salty). Portions were created in response to the following eating situations, or "contexts": What they would a) eat to stay healthy (healthy), b) typically eat (typical), c) eat to feel comfortably satisfied (satisfied), d) consider the most that they could tolerate eating (maximum), and e) eat if nothing was limiting them (desired). Tasks were completed before, and 3 months after, surgery in patients, and at two visits, 3 months apart, in controls. Body weight (kg) was recorded at both visits. Virtual portions differed significantly across groups, visits, eating contexts, energy densities (low vs. high), and tastes (sweet vs. salty). Portions created by controls did not change over time, while portions created by patients decreased significantly after surgery, for all contexts except healthy. For patients, desired and healthy portions predicted 3-month weight loss. VPCTs are replicable, responsive to foods and eating contexts, and predict surgical weight loss. These tasks could be useful for individual assessment of expectations of amounts that are eaten in health and disease and for prediction of weight loss.

Ongoing Inconsistencies in Weight Loss Reporting Following Bariatric Surgery: a Systematic Review

Weight loss is the primary outcome following bariatric surgery; however, its documentation within current literature is heterogeneous and poorly defined, limiting meaningful comparison between studies. Randomized controlled trials from 2012 to 2016 were identified using the Medline database through "Gastric bypass OR sleeve gastrectomy AND weight" search terms. A total of 73 studies with 5948 patients were included. Reporting of preoperative weight was done primarily using mean body mass index (BMI) (87.7%) and mean weight (65.8%). Postoperative weight reporting was more variable, with the most frequently reported measure being mean postoperative BMI (71.2%). Overall, nearly one third of all bariatric literature contained discrepancies that precluded meaningful meta-analysis. Reporting of weight loss following bariatric surgery is becoming increasingly diverse for both pre- and post-operative outcomes. Ongoing heterogeneity will continue to act as a barrier to meaningful comparison of bariatric outcomes until standardized reporting practices become adopted.

Dilatation of Sleeve Gastrectomy: Myth or Reality?

OBJECTIVES

The success of longitudinal sleeve gastrectomy (LSG) is perceived as being potentially limited by dilatation of the remaining gastric tube during the follow-up. The aim of this prospective study was to determine the incidence and the characteristics of sleeve dilatation during the first post-operative year.

MATERIALS AND METHODS

Gastric volumetry using 3D gastric computed tomography with gas expansion was performed in 54 successive subjects who underwent an LSG for morbid obesity at 3 and 12 months following surgery. Total gastric volume, volume of the gastric tube and the antrum, and diameter of the gastric tube were assessed after multiplanar reconstructions. An increase of at least 25 % of the total gastric volume was considered as sleeve dilatation. Percentage of excess BMI loss (%EBMIL) and daily caloric intakes were recorded during the first 18 months.

RESULTS

Sixty-one percent of the subjects experienced sleeve dilatation 1 year after surgery. The gastric tube was mainly involved in the sleeve dilatation process (+91 %). Sleeve dilatation occurred especially in subjects with smaller total gastric volume at baseline (189 vs 236 ml, p = 0.02). Daily caloric intake was similar between the groups at each point of the follow-up. No difference concerning %EBMIL was observed between the groups during the 18 months of follow-up.

CONCLUSIONS

Sleeve dilatation occurred in more than 50 % of the patients. Dilatation was not necessarily linked to an increase of daily caloric intake and insufficient weight loss during the first 18 months following surgery. Small LSG at baseline is at higher risk of dilatation.

Long-term success and failure with SG is predictable by 3 months: a multivariate model using simple office markers

INTRODUCTION

Despite being the most common surgery in the United States, little is known about predicting weight loss success and failure with sleeve gastrectomy (SG). Papers that have been published are inconclusive. We decided to use multivariate analysis from 2 practices to design a model to predict weight loss outcomes using data widely available to any surgical practice at 3 months to determine weight loss outcomes at 1 year.

SETTING

Two private practices in the United States.

METHODS

A retrospective review of 613 patients from 2 bariatric institutions were included in this study. Co-morbidities and other preoperative characteristics were gathered, and %EWL was calculated for 1, 3, and 12 months. Excess weight loss (%EWL)<55% at 1 year was defined as weight loss failure. Multiple variate analysis was used to find factors that affect %EWL at 12 months.

RESULTS

Preoperative sleep apnea, preoperative diabetes, %EWL at 1 month, and %EWL at 3 months all affect %EWL at 1 year. The positive predictive value and negative predictive value of our model was 72% and 91%, respectively. Sensitivity and specificity were 71% and 91%, respectively.

CONCLUSION

One-year results of the SG can be predicted by diabetes, sleep apnea, and weight loss velocity at 3 months postoperatively. This can help surgeons direct surgical or medical interventions for patients at 3 months rather than at 1 year or beyond.

Sleeve gastrectomy effects on hunger, satiation, and gastrointestinal hormone and motility responses after a liquid meal test

BACKGROUND

The relation between hunger, satiation, and integrated gastrointestinal motility and hormonal responses in morbidly obese patients after sleeve gastrectomy has not been determined.

OBJECTIVE

The objective was to assess the effects of sleeve gastrectomy on hunger, satiation, gastric and gallbladder motility, and gastrointestinal hormone response after a liquid meal test.

DESIGN

Three groups were studied: morbidly obese patients (n = 16), morbidly obese patients who had had sleeve gastrectomy (n = 8), and nonobese patients (n = 16). The participants fasted for 10 h and then consumed a 200-mL liquid meal (400 kcal + 1.5 g paracetamol). Fasting and postprandial hunger, satiation, hormone concentrations, and gastric and gallbladder emptying were measured several times over 4 h.

RESULTS

No differences were observed in hunger and satiation curves between morbidly obese and nonobese groups; however, sleeve gastrectomy patients were less hungry and more satiated than the other groups. Antrum area during fasting in morbidly obese patients was statistically significant larger than in the nonobese and sleeve gastrectomy groups. Gastric emptying was accelerated in the sleeve gastrectomy group compared with the other 2 groups (which had very similar results). Gallbladder emptying was similar in the 3 groups. Sleeve gastrectomy patients showed the lowest ghrelin concentrations and higher early postprandial cholecystokinin and glucagon-like peptide 1 peaks than did the other participants. This group also showed an improved insulin resistance pattern compared with morbidly obese patients.

CONCLUSIONS

Sleeve gastrectomy seems to be associated with profound changes in gastrointestinal physiology that contribute to reducing hunger and increasing sensations of satiation. These changes include accelerated gastric emptying, enhanced postprandial cholecystokinin and glucagon-like peptide 1 concentrations, and reduced ghrelin release, which together may help patients lose weight and improve their glucose metabolism after surgery. This trial was registered at clinicaltrials.gov as NCT02414893.