Potential Hormone Mechanisms of Bariatric Surgery

Effects of bariatric surgeries on Binge eating disorders, Food addiction, and eating behaviors: A comprehensive systematic review of RCTs

Different types of bariatric surgery have emerged as a major and most effective treatment for obesity. With the rapid growth of bariatric surgery in this decade, it is crucial to understand the postoperative outcomes, especially eating-related outcomes, such as non-preexisting eating disorders, food addiction, emotional eating, and eating behaviors. This systematic review of RCTs seeks to evaluate the impact of various bariatric surgery procedures on eating behaviors, eating disorders, and food addiction to better understand their post-operative effects and guide future clinical practice. Following the 2015 PRISMA guidelines, a systematic review was conducted using PubMed/Medline, Scopus, and WOS databases through May 2024. After assessing 1158 full-text articles, 14 studies were selected based on the established criteria. Based on the obtained results, bariatric surgery significantly improved eating behaviors and weight concerns among patients. Eating behavior was assessed by various questionnaires, such as TFEQ and PFS, across different types of bariatric surgeries, including RYGB, SG, LSG, DJBL, and LAGB. While some studies found varying degrees of improvements across different surgical procedures, the general trend suggests that bariatric surgery can lead to significant improvements in eating behaviors. In conclusion, bariatric surgery appears to influence eating behaviors, food addiction, and binge eating disorders by altering the gut microbiota, gut hormones, and brain regions associated with appetite. However, there is no significant difference in these outcomes among different types of surgery.

Medication Use Before and After Different Bariatric Surgery Procedures: Results from a Population-Based Cohort Study

BACKGROUND

Metabolic and bariatric surgery improves most obesity-related comorbidities. Here, we evaluate the effect of different metabolic and bariatric surgery interventions on the use of medications to treat chronic conditions.

MATERIALS AND METHODS

This was an observational population-based cohort study performed in Lombardy, Italy. Healthcare utilization databases were used to identify all residents who underwent a metabolic and bariatric surgery procedure between 2010 and 2020 with available follow-up data for at least three years after surgery. We included patients undergoing laparoscopic sleeve gastrectomy (LSG), gastric bypass (GB), laparoscopic adjustable gastric banding (LAGB), and biliopancreatic diversion (BPD).

RESULTS

During the period 2010 to 2020, 19,450 patients (22.5% males, 13.5% with diabetes) underwent a metabolic and bariatric surgery procedure. LSG was the most commonly performed procedure (65%), followed by LAGB (19%), GB (15%), and BPD (1%). There was a significant reduction in the use of glucose-lowering and antihypertensive drugs after the procedure in all groups. Compared to LSG, the reduction in the use of glucose-lowering drugs was greater following GB (reduction at 3 years: 59 vs 65%, p-interaction < 0.001) and lower following LAGB (59 vs 25%, p-interaction < 0.001). There was a significant reduction in lipid-lowering drug use following LSG and GB (3-year reduction: 21 and 50%, p-interaction < 0.001), and in psychiatric drug use following LSG, GB, and LAGB (with no difference between groups). In all groups, proton pump inhibitor use increased during the first 6 months, followed by a decrease from 1 year afterward.

CONCLUSION

The present study including a large number of patients undergoing metabolic and bariatric surgery procedures shows robust reductions in the use of glucose, blood pressure and lipid-lowering drugs at 3 years follow-up, suggesting benefits of surgery on both quality of life and healthcare costs.

The Effects of Metabolic Bariatric Surgery on Intra-pancreatic Fat Deposition and Total Pancreas Volume: a Systematic Review and Meta-analysis

Bariatric procedures are common interventions for weight loss and metabolic improvements; yet, their effects on the pancreas-a key metabolic organ-are largely unknown. This systematic review aimed to summarise data on changes in intra-pancreatic fat deposition (IPFD) and total pancreas volume (TPV) following metabolic bariatric surgery and endoscopic bariatric therapy. The literature search was conducted in MEDLINE and Embase databases. Studies in humans were included if they reported on changes in IPFD and/or TPV from before to after bariatric procedure. Random effects meta-analysis was conducted. Fourteen studies (all involving metabolic bariatric surgery) met the eligibility criteria. Metabolic bariatric surgery resulted in a mean absolute IPFD reduction of 3.9% (p = 0.003) and a mean TPV decrease of 10.7 cm3 (p < 0.001). The mean relative IPFD reduction after metabolic bariatric surgery was 35.9%. Sleeve gastrectomy led to a higher mean relative IPFD reduction than Roux-en-Y gastric bypass (39.9% vs. 20.6%), though this difference was not statistically significant. Analysis of follow-up duration showed a mean relative IPFD reduction of 8.8% in patients with follow-ups of less than 3 months. Metabolic bariatric surgery leads to significant reductions in IPFD and TPV. Follow-up should take place no earlier than 3 months for the full benefits of bariatric procedures on the pancreas to manifest.

Gallstones after bariatric surgery: mechanisms and prophylaxis

Gallstones represent a common yet often underappreciated complication following bariatric surgery, with reported incidence rates ranging widely from 10.4% to 52.8% within the first postoperative year. Multiple factors contribute to gallstone formation in this setting, including intraoperative injury to the hepatic branch of the vagus nerve, alterations in bile composition, reduced food intake, shifts in gastrointestinal hormone levels, and dysbiosis of the gut microbiota. Notably, the risk of cholelithiasis varies by surgical procedure, with sleeve gastrectomy (SG) generally associated with a lower incidence compared to Roux-en-Y gastric bypass (RYGB). Prophylactic cholecystectomy during bariatric surgery may benefit patients with preexisting gallstones, whereas preserving the hepatic branch of the vagus is an important technical consideration, particularly in RYGB, to mitigate postoperative gallstone risk. Pharmacological interventions, such as ursodeoxycholic acid (UDCA), have demonstrated efficacy in preventing gallstones and reducing subsequent cholecystectomy rates. However, consensus is lacking on the optimal dosing, duration, and administration frequency of UDCA across different bariatric procedures. Additionally, dietary measures, such as moderate fat intake or fish oil supplementation, have shown promise in alleviating lithogenic processes. Emerging evidence supports the use of probiotics as a safe and patient-friendly adjunct or alternative to UDCA, given their ability to improve gut dysbiosis and reduce gallstone formation. Further high-quality studies are needed to define standardized prophylactic strategies that balance efficacy with patient adherence, offering personalized gallstone prevention protocols in the era of widespread bariatric surgery.

Advances in Metabolic Bariatric Surgeries and Endoscopic Therapies: A Comprehensive Narrative Review of Diabetes Remission Outcomes

Background and Objectives: Type 2 diabetes (T2D), closely associated with obesity, contributes to increased morbidity and mortality due to complications such as cardiometabolic disease. This review aims to evaluate the effectiveness of metabolic and bariatric surgeries (MBS) and endoscopic bariatric therapies (EBTs) in achieving diabetes remission and to examine key predictors influencing remission outcomes. Materials and Methods: This review synthesizes data from studies on MBS and EBT outcomes, focusing on predictors for diabetes remission such as preoperative insulin use, diabetes duration, HbA1c, and C-peptide levels. Additionally, predictive scoring systems, including the Individualized Metabolic Surgery (IMS), DiaRem, Advanced-DiaRem, ABCD, and Robert et al. scores, were analyzed for their utility in forecasting remission likelihood. Results: Key predictors of T2D remission include shorter diabetes duration, lower HbA1c, and higher C-peptide levels, while prolonged insulin use, and higher insulin doses are associated with lower remission rates. Scoring models like IMS and DiaRem demonstrate that lower scores correlate with a higher likelihood of remission, especially for procedures such as Roux-En-Y gastric bypass (RYGB). RYGB generally shows higher remission rates compared to sleeve gastrectomy (SG), particularly among patients with mild disease severity, while EBTs like ESG and IGBs contribute 5-20% total weight loss (TWL) and moderate glycemic control improvements. Conclusions: Both MBS and EBTs are effective for T2D management, with predictive scoring models aiding in individualized patient selection to optimize remission outcomes. Further research to validate these predictive tools across diverse populations could enhance treatment planning for both surgical and endoscopic interventions.

The approach to a pregnancy after bariatric surgery

With a rising worldwide incidence of obesity, particularly in the young, bariatric surgery offers an effective method of meaningful and sustained weight loss. At present, most bariatric procedures are carried out in women and increasingly in younger age groups. In line with the fertility benefits associated with weight loss, pregnancy after bariatric surgery is now a very common scenario. Although there is limited evidence to support optimal care in this group, most women appear to have good pregnancy outcomes, with reduced rates of pre-eclampsia and gestational diabetes (GDM). However, rates of stillbirth and small-for-gestational-age (SGA) babies are increased, suggesting that screening and supplementation of micronutrients is likely to be very important in this cohort. The risks and benefits that bariatric surgery may pose to pregnancy outcomes, both maternal and fetal, are largely dependent upon the degree of weight loss, weight stability upon entering pregnancy, surgical complications and the time interval between bariatric surgery and pregnancy. Ideally, preconception care would be more widely available, helping to assess and address micronutrient deficiencies and support preparation for pregnancy.

[Sleeve gastrectomy for the surgical management of obesity at the Essos Hospital Center (Yaoundé, Cameroon): a retrospective case series study evaluating medium-term weight loss]

While the prevalence of overweight and obesity is rising in Africa, the practice of bariatric surgery remains limited in our country, Cameroon. Weight loss outcomes following sleeve gastrectomy (SG), the most widely used bariatric surgery technique worldwide, have not yet been studied in our context. The medical records of all patients who underwent SG in our surgery department between January 1, 2016, and September 30, 2020, were reviewed retrospectively. The primary outcome studied was medium-term weight loss, one year after surgery. Weight loss was calculated using the postoperative body mass index (BMI) and the percentage of excess weight loss (%EWL). Reinhold criteria were used to assess the %EWL. We collected data from the medical records of 21 patients, of whom 19 (90.5%) were female. The average age of patients was 40.3±10.8 years, with a mean BMI of 44.9±7.4 kg/m2. All patients had at least one obesity-related comorbidity. All procedures were performed laparoscopically, without conversion, with a mean duration of 192.2±52.8 min. One year after surgery, the mean BMI was 32.51±3.7 kg/m2 and the mean %EWL was 63.35±6.5%. According to Reinhold's criteria, the %EWL was considered satisfactory. In our context, SG provides satisfactory results for medium-term weight loss.

Stronger control of eating 3 months after sleeve gastrectomy predicts successful weight loss outcomes at one year

Background

Weight loss response to sleeve gastrectomy (SG) is variable and predicting the effectiveness of surgery is challenging and elusive. The aim of our study was to assess and quantify the association between eating control and weight loss outcomes and identify the control of eating (CoE) attributes during the early postoperative period that might predict good vs. poor response to SG at one year.

Methods

A prospective longitudinal cohort study using the Control of Eating Questionnaire (CoEQ) was designed as a series before and at 3-, 6-, and 12-months post-SG. Primary outcomes were changes in CoE attributes and percent of total weight loss (%TWL) 12-months post-surgery. Subjects were categorized based on %TWL as good (GR, ≥25 %) or poor responders (PR, <25 %). A receiver operating characteristic and logistic regression analyses were performed.

Results

We included 41 participants (80.5% females, 51.2% Hispanic, mean age 41.7±10.6, median baseline body mass index (BMI) 43.6 kg/m2 [range 35.2-66.3]) who completed the CoEQ at all four timepoints. The "Difficulty to control eating" score at 3 months revealed the highest area under the curve (AUC) (AUC 0.711; 95%CI 0.524-0.898; p=0.032). In a trade-off between a high Youden index and high sensitivity, the "Difficulty to control eating" score of 7 at 3 months was identified as the optimal cut-off for distinguishing between GRs and PRs. Score ≤7 at 3 months was strongly independently associated with a successful weight loss target of 25%TWL at one-year post-SG (Relative Risk 4.43; 95%CI 1.06-18.54; p=0.042).

Conclusion

"Difficulty to control eating" score at 3 months post-SG is an independent early predictor of optimal response (achieving a successful TWL target of ≥25 % at one-year post-SG). Our results support the utility of this easy-to-administer validated tool for predicting the effectiveness of SG and may assist in identifying individuals with suboptimal response early and helping them with interventions to attain optimal weight loss targets.

Metabolic bariatric surgery, alcohol misuse and liver cirrhosis: a narrative review

Bariatric surgery and liver cirrhosis have considerable overlap. Bariatric procedures intend to reduce metabolic dysfunction-associated steatotic liver disease (MASLD); however, these procedures are thought to increase the propensity for alcohol misuse. This may predispose the bariatric surgical patient to a new form of liver insult in the postoperative period. This review explores the complex relationship between obesity and alcohol misuse in the context of the bariatric surgical patient. There is evidence to support the safety of bariatric procedures in compensated cirrhotic patients, with an improvement of liver function and architecture. However, data suggest that after a two-year period, these patients exhibit an increased propensity for alcohol misuse postoperatively, particularly after sleeve gastrectomy (SG) and Roux-en-Y gastric bypass (RYGB) procedures. A paucity of evidence exists with respect to alcohol-induced liver dysfunction, or MASLD and increased alcohol intake (MetALD) in the post-bariatric surgery patient. This review aims to provide an overview of the current evidence and offer recommendations for further robust studies.

Evaluating Fibroblast Growth Factor 21 (FGF21) Levels Post-Gastric Sleeve Surgery in Obese Patients

Background and objectives Obesity is a major global health concern linked with increased risk of chronic diseases. This study aimed to assess the levels of fibroblast growth factor 21 (FGF21) in subjects with obesity after gastric sleeve surgery and explore its correlation with lipid and glycemic parameters. Methods This retrospective cohort study included 28 obese male subjects aged 25 to 50 years, undergoing gastric sleeve surgery. Plasma levels of FGF21 were measured by enzyme-linked immunosorbent assay (ELISA) before and six to 12 months after surgery. Other parameters including body mass index (BMI), fasting glucose, lipid profile, and insulin were also assessed and homeostatic model assessment (HOMA) was used to estimate insulin resistance. Results There was a significant increase in systemic FGF21 levels after surgery (45.12 vs. 126.16 pg/mL, p = 0.007). There was also a notable reduction in BMI (51.55 vs. 39.14, p < 0.001), insulin levels (20.06 vs. 8.85 mIU/L, p < 0.001), HOMA scores (6.94 to 2.49, p < 0.001), and glucose levels (7.33 vs. 6.08, p = 0.039). Lipid profile analysis post-surgery showed an increase in total cholesterol (4.38 vs. 5.09 mmol/L, p < 0.001) and high-density lipoprotein (HDL) (0.88 vs. 1.52 mmol/L, p < 0.001), with a decrease in triglycerides (1.75 vs. 1.01 mmol/L, p = 0.007). FGF21 positively correlated with growth hormone (GH), p = 0.0015, r = 0.59, and with insulin like growth factor 1 (IGF-1), p = 0.03, r = 0.431. Conclusion FGF21 levels were increased following gastric sleeve surgery in obese male patients and were positively correlated with growth hormone and insulin IGF-1. These findings provide insights into the metabolic alterations following bariatric surgery and highlight the potential role of FGF21 as an important molecule in obesity management and treatment.

Marginal Ulcer Incidence and the Population of Gastrin Producing G cells Retained in the Gastric Pouch after Roux-en-Y Gastric Bypass: Is There a Relationship?

INTRODUCTION

Marginal ulcers are the most prevalent endoscopic abnormality after RYGB. The etiology is still poorly understood; however, an increase in acid secretion has been strongly implicated as a causal agent. Although gastrin is the greatest stimulant of acid secretion, to date, the presence of gastrin producing G cells retained in the gastric pouch, related to the occurrence of marginal ulcers, has not been evaluated.

OBJECTIVE

Evaluate the density of G cells and parietal cells in the gastric pouch of RYGB patients with a diagnosis of marginal ulcer on the post-op EGD.

METHOD

We retrospectively evaluated 1104 gastric bypasses performed between 2010 and 2020. Patients with marginal ulcer who met the inclusion criteria and controls were selected from this same population. Endoscopic gastric pouch biopsies were evaluated using immunohistochemical study and HE staining to assess G cell and parietal cell density.

RESULTS

In total, 572 (51.8%) of the patients performed endoscopic follow-up after RYGB. The incidence of marginal ulcer was 23/572 (4%), and 3 patients required revision surgery due to a recalcitrant ulcer. The mean time for ulcer identification was 24.3 months (2-62). G cell count per high-power field (× 400) was statistically higher in the ulcer group (p < 0.05). There was no statistical difference in parietal cell density between groups (p 0.251).

CONCLUSION

Patients with a marginal ulcer after gastric bypass present a higher density of gastrin-producing G cells retained in the gastric pouch.

Duodenal enteroendocrine cells and GIP as treatment targets for obesity and type 2 diabetes

The duodenum is an important source of endocrine and paracrine signals controlling digestion and nutrient disposition, notably including the main incretin hormone glucose-dependent insulinotropic polypeptide (GIP). Bariatric procedures that prevent nutrients from contact with the duodenal mucosa are particularly effective interventions to reduce body weight and improve glycaemic control in obesity and type 2 diabetes. These procedures take advantage of increased nutrient delivery to more distal regions of the intestine which enhances secretion of the other incretin hormone glucagon-like peptide-1 (GLP-1). Preclinical experiments have shown that either an increase or a decrease in the secretion or action of GIP can decrease body weight and blood glucose in obesity and non-insulin dependent hyperglycaemia, but clinical studies involving administration of GIP have been inconclusive. However, a synthetic dual agonist peptide (tirzepatide) that exerts agonism at receptors for GIP and GLP-1 has produced marked weight-lowering and glucose-lowering effects in people with obesity and type 2 diabetes. This appears to result from chronic biased agonism in which the novel conformation of the peptide triggers enhanced signalling by the GLP-1 receptor through reduced internalisation while reducing signalling by the GIP receptor directly or via functional antagonism through increased internalisation and degradation.

Nonclassic Congenital Adrenal Hyperplasia Metabolic Resolution Post Roux-en-Y Gastric Bypass and Associated Weight Loss

Nonclassic congenital adrenal hyperplasia (NCCAH) is characterized by mild cortisol deficiency, excess androgens and adrenocorticotropin (ACTH) production, and often with various features of dysmetabolic syndrome. Elective bariatric surgery is one of the most effective long-term management strategies for severe obesity. Our case presents a 34-year-old woman with symptomatic NCCAH and class III obesity who status post Roux-en-Y gastric bypass (RYGB) had significant weight loss with metabolic resolution of NCCAH, and no longer required glucocorticoid (GC) therapy. At 11 months post operation and off GC therapy, she had a weight deficit of approximately 160 pounds (72.57 kg) with continued metabolic resolution of NCCAH markers including ACTH, 17-hydroxyprogesterone, and androstenedione. Presently, GC therapy remains one of the few available treatments for symptomatic NCCAH; however, long-term GC therapy has the potential for various complications and side effects. Our case presents elective bariatric surgery as a potential and unique treatment option for patients with NCCAH with associated class III obesity. The exact pathophysiologic basis for this effect and its potential role in long-term management of appropriate NCCAH patients requires further study.

The effects of bariatric surgery on cardiac function: a systematic review and meta-analysis

INTRODUCTION

Obesity is associated with alterations in cardiac structure and haemodynamics leading to cardiovascular mortality and morbidity. Culminating evidence suggests improvement of cardiac structure and function following bariatric surgery.

OBJECTIVE

To evaluate the effect of bariatric surgery on cardiac structure and function in patients before and after bariatric surgery.

METHODS

Systematic review and meta-analysis of studies reporting pre- and postoperative cardiac structure and function parameters on cardiac imaging in patients undergoing bariatric surgery.

RESULTS

Eighty studies of 3332 patients were included. Bariatric surgery is associated with a statistically significant improvement in cardiac geometry and function including a decrease of 12.2% (95% CI 0.096-0.149; p < 0.001) in left ventricular (LV) mass index, an increase of 0.155 (95% CI 0.106-0.205; p < 0.001) in E/A ratio, a decrease of 2.012 mm (95% CI 1.356-2.699; p < 0.001) in left atrial diameter, a decrease of 1.16 mm (95% CI 0.62-1.69; p < 0.001) in LV diastolic dimension, and an increase of 1.636% (95% CI 0.706-2.566; p < 0.001) in LV ejection fraction after surgery.

CONCLUSION

Bariatric surgery led to reverse remodelling and improvement in cardiac geometry and function driven by metabolic and haemodynamic factors.

Suboptimal Weight Loss 13 Years After Roux-en-Y Gastric Bypass Is Associated with Blunted Appetite Response

PURPOSE

Bariatric surgery remains the most efficient treatment to achieve a sustained weight loss. However, a large proportion of patients experience suboptimal weight loss (SWL). The exact mechanisms involved remain to be fully elucidated, but the homeostatic appetite control system seems to be involved. The aim of this study was, therefore, to compare the plasma concentration of gastrointestinal hormones, and appetite ratings, between those experiencing SWL and optimal weight loss (OWL) after Roux-en-Y gastric bypass (RYGB).

MATERIALS AND METHODS

Fifty participants from the Bariatric Surgery Observation Study (BAROBS) experiencing either SWL or OWL (< or ≥ 50% of excess weight loss (EWL), respectively) > 13 years post-RYGB were compared to 25 non-surgical controls. Plasma concentrations of acylated ghrelin (AG), total glucagon-like peptide-1 (GLP-1), total peptide YY (PYY), cholecystokinin (CCK), and subjective ratings of hunger, fullness, desire to eat (DTE), and prospective food consumption (PFC) were assessed in the fasting and postprandial (area under the curve (AUC)) states.

RESULTS

Those experiencing OWL presented with higher basal AG and GLP-1 iAUC, and lower AG iAUC compared with SWL and controls. Additionally, both bariatric groups presented with higher PYY and CCK iAUC compared to controls. PFC tAUC was also lower in OWL compared to the SWL group. Total weight loss was positively correlated with GLP-1 tAUC and negatively correlated with fasting and tAUC DTE and PFC tAUC.

CONCLUSIONS

SWL > 13 years post-RYGB is associated with lower basal ghrelin, as well as a weaker satiety response to a meal. Future studies should investigate the causality of these associations.

Reduced risk of de novo Barrett esophagus after bariatric surgery: a national database study

BACKGROUND

Bariatric surgery is an effective treatment for obesity and may decrease the morbidity and mortality of obesity-associated cancers.

OBJECTIVE

We investigated the risk of a new diagnosis of Barrett esophagus (BE) following bariatric surgery compared to screening colonoscopy controls.

SETTING

Large national database including patients who received care in inpatient, outpatient, and specialty care services.

METHODS

A national healthcare database (TriNetX, LLC) was used for this analysis. Cases included adults (aged ≥18 yr) who had undergone either sleeve gastrectomy (SG) or Roux-en-Y gastric bypass (RYGB). Controls included adults undergoing screening colonoscopy and an esophagoduodenoscopy on the same day and had never undergone bariatric surgery. Cases and controls were propensity-matched for confounders. The risk of de novo diagnosis of BE at least 1 year after bariatric surgery was compared between cases and controls. Secondary analyses examined the effect of bariatric surgery on metabolic outcomes such as weight loss and body mass index (BMI). The risk of de novo diagnosis of BE in SG was compared with RYGB. Odds ratios (OR) and 95% CI were used to report on these associations.

RESULTS

In the propensity-matched analysis, patients who had undergone a bariatric surgical procedure showed a significantly reduced risk of de novo BE when compared with screening colonoscopy controls (.67 [.48, .94]). There was substantial reduction in weight and BMI in the bariatric surgery group when compared with baseline. There was no significant difference in de novo BE diagnosis between the propensity-matched SG and RYGB groups (.77 [.5, 1.2]).

CONCLUSION

Patients who underwent bariatric surgery (RYGB or SG) had a lower risk of being diagnosed with BE compared with screening colonoscopy controls who did not receive bariatric surgery. This effect appears to be largely mediated by reduction in weight and BMI.

A data-driven computational model for obesity-driven diabetes onset and remission through weight loss

Obesity is a major risk factor for the development of type 2 diabetes (T2D), where a sustained weight loss may result in T2D remission in individuals with obesity. To design effective and feasible intervention strategies to prevent or reverse T2D, it is imperative to study the progression of T2D and remission together. Unfortunately, this is not possible through experimental and observational studies. To address this issue, we introduce a data-driven computational model and use human data to investigate the progression of T2D with obesity and remission through weight loss on the same timeline. We identify thresholds for the emergence of T2D and necessary conditions for remission. We explain why remission is only possible within a window of opportunity and the way that window depends on the progression history of T2D, individual's metabolic state, and calorie restrictions. These findings can help to optimize therapeutic intervention strategies for T2D prevention or treatment.

Evolution of peptide YY analogs for the management of type 2 diabetes and obesity

Peptide YY (PYY) is a gastrointestinal hormone consisting of 36 amino acids, that is predominantly secreted by intestinal l-cells. Originally extracted from pig intestines, it belongs to the pancreatic polypeptide (PP) family, but has functions distinct from those of PP and neuropeptide Y (NPY). PYY is a potential treatment for type 2 diabetes mellitus (T2DM) because of its ability to delay gastric emptying, reduce appetite, decrease weight, and lower blood glucose. However, the clinical use of PYY is limited because it is rapidly cleared by the kidneys and degraded by enzymes. In recent years, researchers have conducted various structural modifications, including amino acid substitution, PEGylation, lipidation, and fusion of PYY with other proteins to prolong its half-life and enhance its biological activity. This study presents an overview of the recent progress on PYY, including its physiological functions, metabolites and structure-activity relationships.

Metabolic remission precedes possible weight regain after gastric bypass surgery

OBJECTIVE

Some patients regain weight to a variable extent from 1 year after Roux-en-Y gastric bypass surgery (RYGB), though rarely reaching preoperative values. The aim of the present study was to investigate whether, when, and to what extent metabolic remission occurs.

METHODS

Fasting metabolite and lipid profiles were determined in blood plasma collected from a nonrandomized intervention study involving 148 patients before RYGB and at 2, 12, and 60 months post RYGB. Both short-term and long-term alterations in metabolism were assessed. Anthropometric and clinical variables were assessed at all study visits.

RESULTS

This study found that the vast majority of changes in metabolite levels occurred during the first 2 months post RYGB. Notably, thereafter the metabolome started to return toward the presurgical state. Consequently, a close-to-presurgical metabolome was observed at the time when patients reached their lowest weight and glucose level. Lipids with longer acyl chains and a higher degree of unsaturation were altered more dramatically compared with shorter and more saturated lipids, suggesting a systematic and reversible lipid remodeling.

CONCLUSIONS

Remission of the metabolic state was observed prior to notable weight regain. Further and more long-term studies are required to assess whether the extent of metabolic remission predicts future weight regain and glycemic deterioration.

Weight Regain after Bariatric Surgery

Bariatric surgery (BS) is currently the most effective treatment for obesity, with long-lasting weight loss and improvement of related co-morbidities [...].

Psychological Profiles and 12-Month Weight Outcomes of Women Evaluated for Reoperative Bariatric Surgery

BACKGROUND

The use of psychological screening instruments prior to bariatric surgery has been well established. However, there is currently no specific literature on psychological screening of candidates for reoperative bariatric surgery.

METHODS

This study evaluated archival data for 40 women who were candidates for reoperative bariatric surgery and completed the Minnesota Multiphasic Personality Inventory-2 Restructured Form (MMPI-2-RF). Profile analysis examined differences between patient groups who did and did not undergo reoperative surgery. MMPI-2-RF profiles for reoperative patients then were compared to previous samples of preoperative and postoperative patients. Hierarchical linear modeling was used to predict BMI following reoperative surgery over a 12-month period based on MMPI-2-RF scales while controlling for age and initial BMI.

RESULTS

Profile analysis results showed no significant differences on MMPI-2-RF scale scores between reoperative candidates who did and did not undergo a second surgery. With some minor differences attributed to minimization of symptoms, there were no systematic differences in MMPI-2-RF scale scores for reoperative surgery patients compared to preoperative and postoperative patient groups. BMI outcomes over a 12-month period showed that age and initial BMI were significantly better predictors than MMPI-2-RF scores.

CONCLUSIONS

Administration of MMPI-2-RF for reoperative bariatric surgery patients likely is equivalent to its typical use in preoperative screening. Only the MMPI-2-RF Disconstraint scale showed any relationship to BMI outcomes over time following reoperative surgery.

Effect of post-gastric sleeve pyloric length on control of type II diabetes mellitus

Background

Although the effectiveness and safety of laparoscopic sleeve gastrectomy (LSG) have been demonstrated, there is still debate about the best surgical method, with the resection distance from pylorus (DP) being among the most contentious topics. In patients who had LSG for morbid obesity, the effect of the resection distance from the pylorus on the management of type II diabetes mellitus during the postoperative phase was examined.

Patients and methods

After receiving each patient’s agreement, a total of 46 obese individuals were enrolled. Patients were prospectively randomized into two groups, group A (‘AP group’) and group B (‘AR group’), based on the distance between the initial reload firing and the pylorus (4 cm for group A and 2 cm for group B, respectively). Blood sugar levels were measured three, six months, and one year following LSG. After a year of follow-up, the percentage of excess weight loss (%EWL) was calculated.

Results

Postoperative weight was statistically significant lower and EWL% was statistically significant higher in group B: LSG ‘2 cm’ compared to group A: LSG ‘4 cm’. As regard outcomes of type 2 diabetes mellitus after LSG, in spite of nonsignificant statistical value, we reported that there was higher frequency of complete remission after 3, 6 and 12 months in group B: LSG ‘2 cm’ compared to group A: LSG ‘4 cm’ and cases with complete remission were associated with significant higher EWL%.

Conclusion

Patients undergoing laparoscopic sleeve gastrectomy are recommended to have shorter resection distance from pylorus (DP) done. It has been linked to superior surgical results, weight reduction, and diabetes mellitus management with no problems recorded.

Famsin, a novel gut-secreted hormone, contributes to metabolic adaptations to fasting via binding to its receptor OLFR796

The intestine is responsible for nutrient absorption and orchestrates metabolism in different organs during feeding, a process which is partly controlled by intestine-derived hormones. However, it is unclear whether the intestine plays an important role in metabolism during fasting. Here we have identified a novel hormone, famsin, which is secreted from the intestine and promotes metabolic adaptations to fasting. Mechanistically, famsin is shed from a single-pass transmembrane protein, Gm11437, during fasting and then binds OLFR796, an olfactory receptor, to activate intracellular calcium mobilization. This famsin-OLFR796 signaling axis promotes gluconeogenesis and ketogenesis for energy mobilization, and torpor for energy conservation during fasting. In addition, neutralization of famsin by an antibody improves blood glucose profiles in diabetic models, which identifies famsin as a potential therapeutic target for treating diabetes. Therefore, our results demonstrate that communication between the intestine and other organs by a famsin-OLFR796 signaling axis is critical for metabolic adaptations to fasting.

Downregulation of hepatic lncRNA Gm19619 improves gluconeogenesis and lipogenesis following vertical sleeve gastrectomy in mice

Long non-coding RNAs (lncRNAs) are emerging important epigenetic regulators in metabolic processes. Whether they contribute to the metabolic effects of vertical sleeve gastrectomy (VSG), one of the most effective treatments for sustainable weight loss and metabolic improvement, is unknown. Herein, we identify a hepatic lncRNA Gm19619, which is strongly repressed by VSG but highly up-regulated by diet-induced obesity and overnight-fasting in mice. Forced transcription of Gm19619 in the mouse liver significantly promotes hepatic gluconeogenesis with the elevated expression of G6pc and Pck1. In contrast, AAV-CasRx mediated knockdown of Gm19619 in high-fat diet-fed mice significantly improves hepatic glucose and lipid metabolism. Mechanistically, Gm19619 is enriched along genomic regions encoding leptin receptor (Lepr) and transcription factor Foxo1, as revealed in chromatin isolation by RNA purification (ChIRP) assay and is confirmed to modulate their transcription in the mouse liver. In conclusion, Gm19619 may enhance gluconeogenesis and lipid accumulation in the liver.

The Effect of Bariatric Surgery upon Diabetes Mellitus: A Proof of Concept by Using the Case of the Mid-Term Effect of Lap Adjustable Gastric Banding (LAGB) on Patients with Diabetes

Obesity is a worldwide epidemic, with numbers on the rise in the world. Obesity is strongly correlated with increased morbidity and mortality. One of the major factors affecting this increase is comorbid diseases such as diabetes mellitus (DM), which is strongly associated with and dependent on the degree of obesity. Thus, it is not surprising that when efficient surgical treatments were found to battle obesity, researchers soon found them to be relevant and effective for battling DM as well. Laparoscopic Adjustable Gastric Banding (LAGB) is a common surgical treatment for morbid obesity. LAGB has the potential to improve control of the comorbidities of morbid obesity, primarily diabetes mellitus (DM). Our hypothesis was that patients treated with LAGB would have a long-term improvement in the control of DM and that due to its unique mechanism of action, this can lend us a better understanding of how to battle diabetes in an efficient and effective way. This was a cohort study based on patients who underwent LAGB surgery in our institution 4 to 7 years previously and had DM type 2 at the time of surgery. Data were collected from patient’s charts and a telephone interview-based questionnaire including demographics, health status, and quality-of-life assessment (Bariatric Analysis and Reporting Outcome System [BAROS]). Seventy patients participated in the current study. The average follow-up time was 5.1 ± 0.9 years post-surgery. The average weight prior to surgery was 122.0 ± 20.2 kg, and on the day of the interview it was 87.0 ± 17.6 kg (p < 0.001). The average body mass index before surgery was 43.8 ± 5.1, and on the day of the interview it was 31.2 ± 4.8 (p < 0.001). On the day of the interview, 47.1% of the participants were cured of DM (not receiving treatment, whether dietary or pharmacologic). The sum of ranks for diabetes was lower after the surgery (p < 0.001), as was HTN and its treatment (p < 0.001). We have shown in this study that LAGB is an effective treatment for morbid obesity, as well as two comorbidities that come with it—DM type 2 and Hypertension (HTN)—in a longer period than previously shown, and with a unique look at the underlying mechanism of action of this procedure. There is a need for further studies to consolidate our findings and characterize which patients are more prone to enjoy these remarkable surgical benefits.

Changes in interstitial cells and gastric excitability in a mouse model of sleeve gastrectomy

Obesity is a critical risk factor of several life-threatening diseases and the prevalence in adults has dramatically increased over the past ten years. In the USA the age-adjusted prevalence of obesity in adults was 42.4%, i.e., with a body mass index (BMI, weight (kg)/height (m)2) that exceeds 30 kg/m2. Obese individuals are at the higher risk of obesity-related diseases, co-morbid conditions, lower quality of life, and increased mortality more than those in the normal BMI range i.e., 18.5-24.9 kg/m2. Surgical treatment continues to be the most efficient and scientifically successful treatment for obese patients. Sleeve gastrectomy or vertical sleeve gastrectomy (VSG) is a relatively new gastric procedure to reduce body weight but is now the most popular bariatric operation. To date there have been few studies examining the changes in the cellular components and pacemaker activity that occur in the gastric wall following VSG and whether normal gastric activity recovers following VSG. In the present study we used a murine model to investigate the chronological changes of gastric excitability including electrophysiological, molecular and morphological changes in the gastric musculature following VSG. There is a significant disruption in specialized interstitial cells of Cajal in the gastric antrum following sleeve gastrectomy. This is associated with a loss of gastric pacemaker activity and post-junctional neuroeffector responses. Over a 4-month recovery period there was a gradual return in interstitial cells of Cajal networks, pacemaker activity and neural responses. These data describe for the first time the changes in gastric interstitial cells of Cajal networks, pacemaker activity and neuroeffector responses and the time-dependent recovery of ICC networks and normalization of motor activity and neural responses following VSG.

Changes in appetite, taste, smell, and food aversion in post-bariatric patients and their relations with surgery time, weight loss and regain

PURPOSE

We aimed to study the occurrence of long-term changes in appetite, taste, smell perceptions, and food aversion in patients following bariatric surgery. Additionally, we compared two surgery types, excess weight loss, rate of weight regain, and time since surgery.

METHODS

This cross-sectional study included 146 post-bariatric patients who were without regular medical follow-up (126 post-Roux-en-Y gastric bypass [RYGB] and 20 post-sleeve gastrectomy [SG]), aged 42 ± 8 years, BMI of 32.6 ± 6.3 kg/m², with excess weight loss of 87.5 ± 20.2%, rate of weight regain (RWR) of 15.4 [3.9-30.9]% and time since surgery of 5.0 ± 4.0 years. They answered a questionnaire about sensory and food perceptions at their first medical appointment at our unit.

RESULTS

Changes in appetite (76%), taste (48.6%), and an increased sensation for sweet taste (60.2%) frequently occurred in our sample. Sensory and food aversion perceptions, taste changes to specific foods, and loss level of taste and smell were similar between RYGB and SG. No differences between patients with or without changes in appetite, taste, smell, and food aversion perceptions concerning excess weight loss were observed. The RWR in post-RYGB was lower in those with changes in taste and smell (P = 0.05). Sensory changes were noted in those with shorter time since surgery for both surgeries (P ≤ 0.05).

CONCLUSION

Changes in appetite and taste occurred frequently in our patients even in the long term. Post-RYGB patients with lower RWR had more changes in taste and smell while a shorter time since surgery showed more frequent changes in appetite, taste, and smell.

LEVEL OF EVIDENCE

Level V, cross-sectional study.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov (NCT04193384).

Bariatric surgery, gastrointestinal hormones, and the microbiome: An Obesity Medicine Association (OMA) Clinical Practice Statement (CPS) 2022

Background

This Obesity Medicine Association (OMA) Clinical Practice Statement (CPS) is intended to provide clinicians an overview of bariatric surgery (i.e., bariatric procedures that improve metabolic disease are often termed "metabolic and bariatric surgery"), gastrointestinal hormones, and the microbiome as they relate to patients with obesity.

Methods

The scientific information for this CPS is based upon published scientific citations, clinical perspectives of OMA authors, and peer review by the Obesity Medicine Association leadership.

Results

This CPS includes the pros and cons of the most common types of bariatric procedures; the roles of gastrointestinal (GI) hormones in regulating hunger, digestion, and postabsorptive nutrient metabolism; and the microbiome's function and relationship with body weight. This CPS also describes patient screening for bariatric surgery, patient care after bariatric surgery, and treatment of potential nutrient deficiencies before and after bariatric surgery. Finally, this CPS explores the interactions between bariatric surgery, GI hormones, and the microbiome.

Conclusions

This Obesity Medicine Association (OMA) Clinical Practice Statement (CPS) regarding bariatric surgery, gastrointestinal hormones, and the microbiome is one of a series of OMA CPSs designed to assist clinicians in the care of patients with the disease of obesity. Implementation of appropriate care before and after bariatric surgery, as well as an awareness of GI hormones and the microbiome, may improve the health of patients with obesity, especially patients with adverse fat mass and adiposopathic metabolic consequences.

Anti-Obesity Medications and Investigational Agents: An Obesity Medicine Association (OMA) Clinical Practice Statement (CPS) 2022

Background

This "Anti-Obesity Medications and Investigational Agents: An Obesity Medicine Association Clinical Practice Statement 2022" is intended to provide clinicians an overview of Food and Drug Administration (FDA) approved anti-obesity medications and investigational anti-obesity agents in development.

Methods

The scientific information for this Clinical Practice Statement (CPS) is based upon published scientific citations, clinical perspectives of OMA authors, and peer review by the Obesity Medicine Association leadership.

Results

This CPS describes pharmacokinetic principles applicable to those with obesity, and discusses the efficacy and safety of anti-obesity medications [e.g., phentermine, semaglutide, liraglutide, phentermine/topiramate, naltrexone/bupropion, and orlistat, as well as non-systemic superabsorbent oral hydrogel particles (which is technically classified as a medical device)]. Other medications discussed include setmelanotide, metreleptin, and lisdexamfetamine dimesylate. Data regarding the use of combination anti-obesity pharmacotherapy, as well as use of anti-obesity pharmacotherapy after bariatric surgery are limited; however, published data support such approaches. Finally, this CPS discusses investigational anti-obesity medications, with an emphasis on the mechanisms of action and summary of available clinical trial data regarding tirzepatide.

Conclusion

This "Anti-Obesity Medications and Investigational Agents: An Obesity Medicine Association Clinical Practice Statement 2022" is one of a series of OMA CPSs designed to assist clinicians in the care of patients with pre-obesity/obesity.

Changes in Gastric Inhibitory Polypeptide (GIP) After Roux-en-Y Gastric Bypass in Obese Patients: a Meta-analysis

This meta-analysis aimed to evaluate changes in GIP after RYGB in obese patients. We searched PubMed, EMBASE, and CENTRAL for relevant studies from database inception through July 2021. Articles were eligible for inclusion if they reported pre-operative and post-operative fasting GIP levels. We found fasting GIP levels had a decreasing tendency. The decrease in fasting glucose and postprandial GIP levels was also observed. Subgroup analysis indicated diabetic subjects tended to have a more obvious fasting GIP reduction compared to non-diabetic individuals. Meta-regression showed that the amount of weight loss (% total body weight), gastric pouch volume, alimentary limb length, and biliopancreatic limb length were not related to fasting GIP decrease. Fasting GIP levels decreased significantly after RYGB in obese people, especially in diabetic patients.

Neurohormonal Changes in the Gut-Brain Axis and Underlying Neuroendocrine Mechanisms following Bariatric Surgery

Obesity is a complex, multifactorial disease that is a major public health issue worldwide. Currently approved anti-obesity medications and lifestyle interventions lack the efficacy and durability needed to combat obesity, especially in individuals with more severe forms or coexisting metabolic disorders, such as poorly controlled type 2 diabetes. Bariatric surgery is considered an effective therapeutic modality with sustained weight loss and metabolic benefits. Numerous genetic and environmental factors have been associated with the pathogenesis of obesity, while cumulative evidence has highlighted the gut-brain axis as a complex bidirectional communication axis that plays a crucial role in energy homeostasis. This has led to increased research on the roles of neuroendocrine signaling pathways and various gastrointestinal peptides as key mediators of the beneficial effects following weight-loss surgery. The accumulate evidence suggests that the development of gut-peptide-based agents can mimic the effects of bariatric surgery and thus is a highly promising treatment strategy that could be explored in future research. This article aims to elucidate the potential underlying neuroendocrine mechanisms of the gut-brain axis and comprehensively review the observed changes of gut hormones associated with bariatric surgery. Moreover, the emerging role of post-bariatric gut microbiota modulation is briefly discussed.

Trends in insulin-like growth factor-1 levels after bariatric surgery: a systematic review and meta-analysis

According to studies, there are many inconsistencies in how IGF-1 levels change after bariatric surgery compared to before surgery, as well as its effects. These discrepancies can be attributed to various factors such as age, body mass index (BMI), and duration of intervention. Therefore, the aim of this study was to evaluate the level of insulin-like growth factor-1 (IGF-1) after bariatric surgery. A systematic review and meta-analysis based on the PRISMA guidelines was conducted from inception until 2021. From 1871 articles initially selected, 24 studies with 28 treatment arms met the eligible criteria and were included. Pooled findings from the random-effects model indicated that IGF-1 levels increased significantly [weighted mean difference (WMD) = 8.84 ng/ml; 95% confidence interval (CI) 0.30-17.39; p = 0.043] after bariatric surgery compared to before surgery. No significant heterogeneity was noted among the studies (Cochran Q test, p = 0.90, I² = 0.0%). In subgroup analysis, bariatric surgery significantly increased IGF-1 levels at age <40 years but not at age ≤40 years. Bariatric surgery is capable of increasing the IGF-1 levels compared to the period prior to surgery but with a modest clinical magnitude.

Mechanisms of Weight Loss After Obesity Surgery

Obesity surgery remains the most effective treatment for obesity and its complications. Weight loss was initially attributed to decreased energy absorption from the gut but has since been linked to reduced appetitive behavior and potentially increased energy expenditure. Implicated mechanisms associating rearrangement of the gastrointestinal tract with these metabolic outcomes include central appetite control, release of gut peptides, change in microbiota, and bile acids. However, the exact combination and timing of signals remain largely unknown. In this review, we survey recent research investigating these mechanisms, and seek to provide insights on unanswered questions over how weight loss is achieved following bariatric surgery which may eventually lead to safer, nonsurgical weight-loss interventions or combinations of medications with surgery.

A multi-center study on glucometabolic response to bariatric surgery for different subtypes of obesity

OBJECTIVES

To assess the benefit of a bariatric surgery in four artificial intelligence-identified metabolic (AIM) subtypes of obesity with respect to the improvement of glucometabolism and the remission of diabetes and hyperinsulinemia.

METHODS

This multicenter retrospective study prospectively collected data from five hospitals in China from 2010 to 2021. At baseline 1008 patients who underwent a bariatric surgery were enrolled (median age 31 years; median BMI 38.1kg/m²; 57.40% women) and grouped into the four AIM subtypes. Baseline and follow-up data (506 and 359 patients at 3- and 12-month post-surgery) were collected for longitudinal effect analysis.

RESULTS

Out of the four AIM subgroups, hypometabolic obesity (LMO) group was characterized by decompensated insulin secretion and high incidence of diabetes (99.2%) pre-surgery. After surgery, 62.1% of LMO patients with diabetes achieved remission, lower than the other three subgroups. Still, the bariatric surgery significantly reduced their blood glucose (median HbA1c decreased by 27.2%). The hypermetabolic obesity-hyperinsulinemia (HMO-I) group was characterized by severe insulin resistance and high incidence of hyperinsulinemia (87.8%) pre-surgery, which had been greatly alleviated post-surgery. For both metabolic healthy obesity (MHO) and hypermetabolic obesity-hyperuricemia (HMO-U) groups who showed a relatively healthy glucometabolism pre-surgery, rate of glucometabolic comorbidities improved moderately post-surgery.

CONCLUSION

In terms of glucometabolism, the four AIM subtypes of patients benefited differently from a bariatric surgery, which significantly relieved hyperglycemia and hyperinsulinemia for the LMO and HMO-I patients, respectively. The AIM-based subtypes may help better inform clinical decisions on bariatric surgery and patient counseling pertaining to post-surgery outcomes.

GASTROESOPHAGEAL SYMPTOMS AFTER LAPAROSCOPIC GASTRIC BYPASS: MISTAKES IN PERFORMING THE PROCEDURE?

Laparoscopic Roux-en-Y gastric bypass (LGB) is the recommended procedure for morbidly obese patients with gastroesophageal reflux disease (GERD). However, there have been reported gastroesophageal reflux symptoms or esophagitis after LGB. Few functional esophageal studies have been reported to date.

A nonhuman primate model of vertical sleeve gastrectomy facilitates mechanistic and translational research in human obesity

The obesity epidemic significantly contributes to overall morbidity and mortality. Bariatric surgery is the gold standard treatment for obesity and metabolic dysfunction, yet the mechanisms by which it exerts metabolic benefit remain unclear. Here, we demonstrate a model of vertical sleeve gastrectomy (VSG) in nonhuman primates (NHP) that mimics the complexity and outcomes in humans. We also show that VSG confers weight loss and durable metabolic benefit, where equivalent caloric intake in shams resulted in significant weight gain following surgery. Furthermore, we show that VSG is associated with early, weight-independent increases in bile acids, short-chain fatty acids, and reduced visceral adipose tissue (VAT) inflammation with a polarization of VAT-resident immunocytes toward highly regulatory myeloid cells and Tregs. These data demonstrate that this strongly translational NHP model can be used to interrogate factors driving successful intervention to unravel the interplay between physiologic systems and improve therapies for obesity and metabolic syndrome.

The Effect of Bariatric Surgery on Circulating Levels of Oxidized Low-Density Lipoproteins Is Apparently Independent of Changes in Body Mass Index: A Systematic Review and Meta-Analysis

BACKGROUND

Obesity is related to dyslipidemia and increased circulating oxidated LDL (ox-LDL) concentrations that may predispose to atherosclerosis. Bariatric surgery may lower the risk of cardiovascular mortality. Elevated plasma ox-LDL has been associated with atherogenesis and atherosclerotic cardiovascular disease (ASCVD) events. The aim of this meta-analysis was to investigate the impact of bariatric surgery on proatherogenic circulating ox-LDL levels in patients with severe obesity.

METHODS

Four databases were systematically searched from inception to May 1, 2021. Also, to clarify the heterogeneity of studies with regard to treatment duration, research design, and the demographic features, a random-effects model and the generic inverse variance weighting approach were utilized. To determine the association with the estimated effect size, a random-effect meta-regression approach was performed. Finally, a meta-regression analysis was conducted to explore the influence of, respectively, baseline and changes in body mass index (BMI), baseline ox-LDL, and postsurgery follow-up period with the estimated effect size of surgery on ox-LDL levels.

RESULTS

Meta-analysis of 11 studies including 470 subjects showed a significant decline in circulating ox-LDL following bariatric surgery (SMD: -0.971, 95% CI: -1.317, -0.626, p < 0.001, I 2: 89.43%). The results of meta-regression did not show any significant association between the changes in ox-LDL after bariatric surgery and baseline BMI, duration of follow-up or baseline ox-LDL values. However, there was a significant association between ox-LDL alteration and percentage of BMI change.

CONCLUSION

Bariatric surgery in patients who had severe obesity causes a decrease of circulating ox-LDL that was apparently dependent in BMI changes.

Improvement in mood symptoms ​after post-bariatric surgery among people with obesity: A systematic review and meta-analysis

AIMS

We aimed to examine if bariatric surgery was associated with a reduction in the prevalence of depressive and anxiety symptoms among people with obesity.

MATERIALS AND METHODS

We pooled data from 49 studies involving 11,255 people with obesity who underwent bariatric surgery. The study outcomes were the prevalence of depressive and anxiety symptoms among these patients pre- and post-surgery.

RESULTS

There was a significant reduction in body mass index (BMI) post-operatively (pooled d+: -13.3 kg/m² [95% confidence interval [CI] 15.19, -11.47], p < 0.001). The pooled proportion of patients with anxiety symptoms reduced from 24.5% pre-operatively to 16.9% post-operatively, with an odds ratio (OR) of 0.58 (95% CI 0.51, 0.67, p < 0.001). The reduction remained significant in women aged ≥40 years and irrespective of post-operative BMI. There were significant reductions in Hospital Anxiety and Depression Score (HADS) (anxiety component) by 0.64 (pooled d+: -0.64 [95% CI -1.06, -0.22], p = 0.003) and Generalized Anxiety Disorder Assessment-7 score by 0.54 (pooled d+: -0.54 [95% CI -0.64, -0.44], p < 0.001). The pooled proportion of depressive symptoms reduced from 34.7% pre-operatively to 20.4% post-operatively, with an OR of 0.49 (95% CI 0.37, 0.65, p < 0.001). The reduction remained significant irrespective of patient's age and post-operative BMI. There were also significant reductions in HADS score (depressive component) (pooled d+: -1.34 [95% CI -1.93, -0.76], p < 0.001), Beck's Depression Inventory score (pooled d+: -1.04 [95% CI -1.46, -0.63], p < 0.001) and Patient Health Questionnaire-9 score (pooled d+: -1.11 [95% CI -1.21, -1.01], p < 0.001).

CONCLUSION

Bariatric surgery was associated with significant reduction in the prevalence and severity of depressive and anxiety symptoms among people with obesity.

Change of plasma amylin after bariatric surgery challenged by oral glucose is associated with remission of type 2 diabetes mellitus

BACKGROUND

Gastric bypass (GB) and sleeve gastrectomy (SG) were found to achieve different remission rates in the treatment of type 2 diabetes (T2DM). The alteration in several gut hormones after bariatric surgery has been demonstrated to play a key role for T2DM remission. Nevertheless, amylin, one of the diabetes-associated peptides, so far has an undetermined position on T2DM remission after bariatric surgery.

METHODS

Sixty eligible patients with T2DM (GB, 30; SG, 30) were initially enrolled in the hospital-based randomized trial. Twenty patients (GB, 10; SG, 10) who met the inclusion criteria and agreed to undergo 75-g oral glucose tolerance test (OGTT) were recruited. The recruited subjects underwent anthropometric measurements, routine laboratory tests, and 75-g OGTT before and 1 year after bariatric surgery. Enzyme immunoassays for plasma amylin were analyzed.

RESULTS

All subjects that underwent GB and half of those who underwent SG achieved T2DM remission. Plasma amylin levels significantly decreased 60-90 min after OGTT in the GB group (p < 0.05) and 30-60 minutes after OGTT in the SG group (p < 0.05). Significantly decreased plasma amylin levels were observed at 30-90 minutes after OGTT in the noncomplete remitters of the GB group (p < 0.05). Plasma amylin levels initially increased (p < 0.05) within 30 minutes after OGTT and then decreased (p < 0.05) in the next 30-minute interval in the nonremitters of the SG group.

CONCLUSION

Postoral glucose challenge amylin levels could be as one of the parameters to evaluate T2DM remission after bariatric surgery, especially in those after SG.

Review of Changes in the Reinforcing Effects of Alcohol in Weight Loss Surgery Patients

PURPOSE OF REVIEW

The reinforcing effects of alcohol are well documented, and they have been shown to play a role in the development of alcohol use disorders (AUDs). Also well established is the fact that post-weight loss surgery (WLS) patients are at an increased risk for AUDs. In the current manuscript, we review the notion that the reinforcing effects of alcohol may change from before to after WLS and discuss a number of determinants of alcohol reinforcement change in WLS patients.

RECENT FINDINGS

It has been increasingly well understood that WLS patients are at an increased risk for AUD, but empirical support for the mechanisms that may cause this phenomenon have been lacking. Recently, a model was proposed that offered a number of different potentially causal variables as mechanisms that result in increased risk for AUD in these surgical patients. Change in the extent to which alcohol is reinforcing to WLS patients may be key in determining the likelihood of AUDs in this group. We review a host of biological, psychological, and social variables that ultimately impact how reinforcing alcohol is to WLS patients.

Laparoscopic Sleeve Gastrectomy has A Positive Impact on Subclinical Hypothyroidism Among Obese Patients: A Prospective Study

BACKGROUND

The effect of bariatric surgery on postoperative thyroid function remains incompletely understood. In this study, we aimed to evaluate the changes in thyroid functions after gastric sleeve operation for morbidly obese Egyptian patients.

METHODS

This was a prospective study that recruited 128 patients who underwent sleeve gastrectomy through the period from December 2016 to April 2020. We measured thyroid-stimulating hormone (TSH), free thyroxin (FT4), and free triiodothyronine. Subclinical hypothyroidism was defined by a TSH level > 4.5 mIU/L but a normal FT4 level. All patients were followed for 12 months after the procedure.

RESULTS

Preoperatively, 30 (23.4%) patients had subclinical hypothyroidism. The prevalence of subclinical hypothyroidism decreased significantly to reach 7.8% at the end of follow-up (p < 0.001). None of the patients developed de novo hypothyroidism at the end of follow-up. Patients with subclinical hypothyroidism were more likely to be females (p = 0.037) and had significantly higher waist circumference (p < 0.001), DBP (p = 0.02), serum cholesterol (p < 0.001), and serum triglyceride (p < 0.001). However, patients with subclinical hypothyroidism at the end of follow-up had significantly higher BMI at the end of the sixth month (p = 0.048). Similarly, patients with subclinical hypothyroidism at the end of follow-up had significantly higher serum cholesterol (p = 0.002), LDL, (p = 0.038), and serum triglyceride (p < 0.001) at the end of the sixth months of follow-up. A similar trend was noted at the end of the 12th month. The preoperative value of serum TSH correlated significantly with serum cholesterol and triglyceride levels.

CONCLUSION

The positive effect of the LSG procedure on the hypothyroid bariatric population, including enhanced thyroid function, was demonstrated.

Are the Changes in Gastrointestinal Hormone Secretion Necessary for the Success of Bariatric Surgery? A Critical Review of the Literature

Ghrelin, glucagon-like peptide-1 (GLP-1), and peptide YY (PYY) are involved in energy balance regulation and glucose homeostasis. Obesity is characterized by lower fasting levels and blunted postprandial responses of ghrelin, GLP-1, and possibly PYY. Both Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG) have been shown to increase postprandial GLP-1 and PYY levels. Human studies have shown that enhanced postprandial GLP-1 and PYY release are associated with favorable weight loss outcomes after RYGB. However, studies in knockout mice have shown that GI hormones are not required for the primary metabolic effects of bariatric surgery. Here, we summarize the complex interaction between obesity, bariatric surgery, and GI hormones in order to determine the exact role of GI hormones in the success of bariatric surgery.

Sleeve Gastrectomy and Roux-En-Y Gastric Bypass. Two Sculptors of the Pancreatic Islet

Several surgical procedures are performed for the treatment of obesity. A main outcome of these procedures is the improvement of type 2 diabetes mellitus. Trying to explain this, gastrointestinal hormone levels and their effect on organs involved in carbohydrate metabolism, such as liver, gut, muscle or fat, have been studied intensively after bariatric surgery. These effects on endocrine-cell populations in the pancreas have been less well studied. We gathered the existing data on these pancreatic-cell populations after the two most common types of bariatric surgery, the sleeve gastrectomy (SG) and the roux-en-Y gastric bypass (RYGB), with the aim to explain the pathophysiological mechanisms underlying these surgeries and to improve their outcome.

Effect of Medical and Surgical Interventions on α-Cell Function in Dysglycemic Youth and Adults in the RISE Study

OBJECTIVE

To compare effects of medications and laparoscopic gastric band surgery (LB) on α-cell function in dysglycemic youth and adults in the Restoring Insulin Secretion (RISE) Study protocols.

RESEARCH DESIGN AND METHODS

Glucagon was measured in three randomized, parallel, clinical studies: 1) 91 youth studied at baseline, after 12 months on metformin alone (MET) or glargine followed by metformin (G/M), and 3 months after treatment withdrawal; 2) 267 adults studied at the same time points and treated with MET, G/M, or liraglutide plus metformin (L+M) or given placebo (PLAC); and 3) 88 adults studied at baseline and after 12 and 24 months of LB or MET. Fasting glucagon, glucagon suppression by glucose, and acute glucagon response (AGR) to arginine were assessed during hyperglycemic clamps. Glucagon suppression was also measured during oral glucose tolerance tests (OGTTs).

RESULTS

No change in fasting glucagon, steady-state glucagon, or AGR was seen at 12 months following treatment with MET or G/M (in youth and adults) or PLAC (in adults). In contrast, L+M reduced these measures at 12 months (all P ≤ 0.005), which was maintained 3 months after treatment withdrawal (all P < 0.01). LB in adults also reduced fasting glucagon, steady-state glucagon, and AGR at 12 and 24 months (P < 0.05 for all, except AGR at 12 months [P = 0.098]). Similarly, glucagon suppression during OGTTs was greater with L+M and LB. Linear models demonstrated that treatment effects on glucagon with L+M and LB were largely associated with weight loss.

CONCLUSIONS

Glucagon concentrations were reduced by L+M and LB in adults with dysglycemia, an effect principally attributable to weight loss in both interventions.

Secretin as a Satiation Whisperer With the Potential to Turn into an Obesity-curbing Knight

The obesity pandemic requires effective preventative and therapeutic intervention strategies. Successful and sustained obesity treatment is currently limited to bariatric surgery. Modulating the release of gut hormones is considered promising to mimic bariatric surgery with its beneficial effects on food intake, body weight, and blood glucose levels. The gut peptide secretin was the first molecule to be termed a hormone; nevertheless, only recently has it been established as a legitimate anorexigenic peptide. In contrast to gut hormones that crosstalk with the brain either directly or by afferent neuronal projections, secretin mediates meal-associated brown fat thermogenesis to induce meal termination, thereby qualifying this physiological mechanism as an attractive, peripheral target for the treatment of obesity. In this perspective, it is of pivotal interest to deepen our as yet superficial knowledge on the physiological roles of secretin as well as meal-associated thermogenesis in energy balance and body weight regulation. Of note, the emerging differences between meal-associated thermogenesis and cold-induced thermogenesis must be taken into account. In fact, there is no correlation between these 2 entities. In addition, the investigation of potential effects of secretin in hedonic-driven food intake, bariatric surgery and chronic treatment using suitable application strategies to overcome pharmacokinetic limitations will provide further insight into its potential to influence energy balance. The aim of this article is to review the facts on secretin's metabolic effects, address prevailing gaps in our knowledge, and provide an overview on the opportunities and challenges of the therapeutic potential of secretin in body weight control.

DYNAMICS OF GLUCAGON-LIKE PEPTIDE-1 AFTER LAPAROSCOPIC SLEEVE GASTRECTOMY IN PATIENTS WITH TYPE 2 DIABETES MELLITUS ASSOCIATIONS WITH OBESITY

Laparoscopic sleeve gastrectomy (LSG) proved to be a valuable procedure for treating obesity complicated by type 2 diabetes mellitus (T2DM). The mechanism of T2DM resolution after LSG is not yet clearly defined. The objective of the study was to investigate the effect of LSG on the secretion of GLP-1 in patients with T2DM associated with obesity. Plasma GLP-1 levels were evaluated by starvation and 15, 30, 60 and 90 min after the standard carbohydrate preload for breakfast, which included 125 ml of balanced high energy Nutricia Nutridrink Protein. Evaluations were made on the eve of the procedure, for 4 days and 3 months after the operation. In 7 patients with T2DM were diagnosed for the first time, in 3 patients with diabetic history 2 years, in 1 patient – 3.5 years and in 1 patient – 10 years. Mean glycated hemoglobin before surgery was 7.7 ± 1.6%, 3 months after LSG – 5.9 ± 0.4%. The concentration of GLP-1 in 30 minutes before surgery was 6.7 ± 0.9 ng/ml. On the 4th day after LSG, the mean level of GLP-1 was 9.6 ± 0.2 ng/ml, which statistically differed from its level in the pre-operative period, and after 3 months the mean level of GLP-1 statistically increased to 13.7 ± 0.3 ng/ml. Thus LSG leads to an early and significant increase in post-prandial secretion GLP-1 in T2DM patients associated with obesity. The rapid postoperative improvement in signs of carbohydrate metabolism indicates the importance of the incretin effect LSG in the implementation of early compensation mechanisms for T2DM and explains the metabolic activity of this operation.

Experiences of the Bariatric Pre-Surgery Evaluation Process in a National Health Service—An Interpretative Phenomenological Analysis

There is currently little understanding of bariatric patients’ experiences and expectations of the bariatric pre-surgery evaluation (PSE) process. This is especially true for patients within the National Health Service (NHS) in the UK. Consequently, this study undertakes a qualitative study to explore the experiences and expectations of the bariatric PSE amongst patients who had undergone bariatric surgery within the NHS in the UK, using the Interpretative Phenomenological Analysis. Three inter-related superordinate themes were presented: (i) ‘PSE was challenging but essential’, (ii) ‘Coping processes to deal with the PSE’, and (iii) ‘Staff and service evaluation’. Most participants had conflicting feelings about the PSE process as it had both positive and negative impacts on their wellbeing. The process was considered essential for preparation and successful post-surgery adjustment, though the uncertainty of approval was experienced as very distressing. Consequently, participants utilised both external and internal coping strategies, such as social support, researching, or ‘toeing the line’. Participants’ experiences encouraged them to provide feedback about the staff and service, which revealed a preference for a tailored evaluation process. The emerged themes represent an initial framework for helping healthcare providers and researchers to involve patients in service delivery thereby facilitating a patient-centred approach. A starting point is to audit patients’ perspectives routinely. Further investigations are needed to better define, validate, and understand constructs and processes identified in this study.

How Does Fat Mass Change in the First Year After Bariatric Surgery? A Systemic Review and Meta-Analysis

This systematic review and meta-analysis investigated the time-course effect of different type of bariatric surgeries (BS) up to 1 year post-surgery on fat mass (FM) and body fat percentage (BFP) in patients with morbid obesity. We searched PubMed, Scopus, EMBASE, ISI web of science, and Cochrane databases from October 2002 until May 2020 with no restriction in the English language, to find studies examining the effect of BS on FM (kg) and BFP (%) in morbid obese patients. Meta-analysis of 103 studies carried out on data of 18,166 and 14,575 morbid obese patients following BS, showed that BS was associated with a substantial decrease in FM and BFP, respectively, in 1 month (- 8.17 kg [95% CI - 9.07, - 7.27] and - 1.51% [95% CI - 2.56, - 0.46]), 3 months (- 15.75 [95% CI - 17.49, - 14.0] and - 4.90 [95% CI - 5.97, - 3.83]), 6 months (- 22.51 [95% CI - 23.93, - 21.09] and - 8.56% [95% CI - 9.63, - 7.49]), and 12 months (- 29.69 [95% CI - 31.3, - 28.09] and - 13.49% [95% CI - 14.52, - 12.40]) after the surgery. In conclusion, BS was associated with sustained declines in FM and BFP, from 1 to 12 months, with no indication of plateau phase post-surgery post-operatively. The present study emphasizes that post-bariatric care should have more focus on FM loss during 1-year post-surgery to identify the patients at risk for fat loss plateau.