Recent advances in metabolic and bariatric surgery

Assessing Nutritional Deficiencies in Bariatric Surgery Patients: A Comparative Study of Roux-en-Y Gastric Bypass versus Sleeve Gastrectomy

Obesity is a worldwide epidemic, and bariatric surgery is considered the primary treatment for long-term weight loss and managing obesity-related health issues. Sleeve gastrectomy (SG) and Roux-en-Y gastric bypass (RYGB) are the most performed procedures. Nutritional deficiencies are a significant concern following bariatric surgery and can have serious consequences. This study aims to compare the incidence of nutritional deficiencies in patients undergoing RYGB and SG. A retrospective analysis was conducted on the nutritional status of 505 consecutive patients who underwent either RYGB or SG between January and December 2019. Data were collected regarding vitamin B12, folic acid, vitamin D, calcium, PTH, magnesium, hemoglobin, iron, ferritin, and transferrin at preoperative, 6-month, and 12-month intervals post-surgery. The RYGB group showed significantly higher excess weight loss. Vitamin B12, hemoglobin, and ferritin levels were consistently higher in the SG group throughout the study. Vitamin D deficiency was prevalent, with no significant difference between the groups. Vitamin B12 deficiency was significantly more common in the RYGB group (6 months: 17.46% vs. 4.69%, p < 0.001; 12 months: 16.74% vs. 0.93%, p < 0.001). Despite differences in their mechanisms, bariatric surgeries were associated with nutritional deficiencies. It is crucial to efficiently assess, prevent, and manage these deficiencies tailored to each surgical procedure.

One Anastomosis Gastric Bypass as Revisional Surgery Following Sleeve Gastrectomy: A Systematic Review and Meta-Analysis

BACKGROUND

Although sleeve gastrectomy (SG) is the most performed metabolic and bariatric surgery (MBS) worldwide, some patients require conversional procedures due to weight recurrence or late complications. Recently, one-anastomosis gastric bypass (OAGB) gained popularity as a viable option to address those problems. The aim of this meta-analysis is to assess the safety and efficacy of conversional OAGB after primary SG in the management of patients with obesity.

METHODS

Cochrane, Embase, PubMed, Scopus, and Web of Science were searched for articles from their inception to February 2023 by two independent reviewers using the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) system. The review was registered prospectively with PROSPERO (CRD42023403528).

RESULTS

From 1,117 studies screened, twenty studies met the eligibility criteria, with a total of 1,057 patients with obesity undergoing conversional OAGB after primary SG. The mean age ranged from 28.2 to 49.5 years, and 744 patients (75.2%) were women. At one year after revisional OAGB, the pooled mean percent excess weight loss (%EWL) was 65.2% (95%CI: 56.9, 73.4, I2 = 97%). The pooled mean %EWL after conversional OAGB was 71.1% (95%CI: 62.2, 80.0, I2 = 90%) at two years and 71.6% (95%CI: 61.0, 82.2, I2 = 50%) at five years. Additionally, resolution rates of diabetes and hypertension were 65.4% (95%CI: 0.522, 0.785, I2 = 65%) and 58.9% (95%CI: 0.415, 0.762, I2 = 89%), respectively.

CONCLUSIONS

Our meta-analysis demonstrated OAGB as an effective conversional procedure after primary SG in terms of weight loss and obesity-associated medical problems for selected patients. Despite the promising results, further randomized controlled studies with larger sample sizes and more extended follow-up periods are necessary to determine if the OAGB is the best conversional surgery after SG.

Sleeve Gastrectomy Provides Cardioprotection from Oxidative Stress In Vitro Due to Reduction of Circulating Myeloperoxidase

Bariatric surgery, including sleeve gastrectomy (SG), improves systolic and diastolic function, which is independent of weight loss in rodent models. The cause of weight loss-independent improvements in cardiac function are unknown but may originate from the gastrointestinal tract. In this study, we investigated whether a circulating blood factor is a mechanism for acute cardioprotection after SG by testing the utility of rodent SG plasma to reduce metabolic stress in vitro. For the initial experiment, obese male Zucker rats underwent SG, ad lib sham, or pair-fed sham surgeries (n = six SG, n = eight SH, n = eight PF). For all other studies, a second group of Zucker rats underwent SG or ad lib sham surgeries (n = eight SH, n = six SG). Six weeks following surgery, plasma was collected from each group, both in the fasting and post-prandial (pp) state. This plasma was then pooled per surgical group and nutrient state and tested in multiple in vitro cell culture and extra-cellular assays to determine the effect of SG on myotubular metabolic stress compared to the sham surgeries. Post-prandial SG plasma (ppSG), but not fasting SG, pp, or fasting sham plasma, reduced the metabolic stress of the H9c2 cells as measured by lactate dehydrogenase (LDH) release (p < 0.01). Unlike SG, weight reduction through pair-feeding did not prevent H9c2 metabolic stress. The PpSG plasma had the slowest rate of extracellular hydrogen peroxide consumption and peroxidatic activity compared to the pp sham, fasting SG, and fasting sham groups. Redox testing of plasma with aminiobenzoic acid hydrazide and edaravone suggested a pattern supporting myeloperoxidase (MPO), or other peroxidases, as the primary component responsible for reduced metabolic stress with ppSG plasma. The PpSG plasma contained 35% less circulating MPO protein as compared to the pp sham and fasting SG plasma. The plasma from an MPO global knockout rat also prevented metabolic stress of the H9c2 cells, compared to the significant increase in LDH release from the plasma of the WT controls (p < 0.01). The MPO global knockout plasma also had a rate of extracellular hydrogen peroxide consumption and peroxidatic activity comparable to the ppSG plasma. These studies suggest that one of the weight loss-independent mechanisms by which SG improves myocellular function could be a reduced pro-oxidative environment due to lower circulating levels of MPO. It appears that the gastrointestinal tract is of critical importance to these findings, as the MPO levels were only lowered after enteral, nutrient stimulation in the SG rats. If this surgical effect is confirmed in humans, SG may be a unique surgical treatment for multiple diseases with a pathogenesis of inflammation and oxidative damage, including obesity-associated heart failure with preserved ejection fraction.

Management of non-alcoholic fatty liver disease patients with sleep apnea syndrome

Nonalcoholic fatty liver disease (NAFLD) is strongly associated with sleep apnea syndrome (SAS). Many NAFLD patients have SAS, and obstructive sleep apnea hypopnea syndrome is also considered to be an independent risk factor for NAFLD, as it contributes to the progression of NAFLD via oxidative stress, lipid peroxidation, inflammation, and insulin resistance. This review aims to provide some recommendations for the management of NAFLD patients with SAS, including diet, exercise, weight loss, and continuous positive airway pressure. This review also highlights the importance of effective strategies in NAFLD prevention and treatment.

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.

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.

Genetic polymorphisms are not associated with energy intake one year after Roux-Y gastric bypass (RYGB) in women

BACKGROUND

This study aimed to investigate the influence of food intake on body weight loss and the association of gene polymorphisms, 1 year after Roux-en-Y gastric bypass (RYGB) surgery.

METHODS

In total, ninety-five obese women (age ranged 20-50 years) in a Brazilian cohort underwent RYGB surgery and completed the study. Anthropometric measurements and food intake were assessed before and 1 year after surgery. Twelve gene polymorphisms (GHRL rs26802; GHSR rs572169; LEP rs7799039; LEPR rs1137101; 5-HT2C rs3813929; UCP2 rs659366; UCP2 rs660339; UCP3 rs1800849; SH2B1 rs7498665; TAS1R2 rs35874116; TAS1R2 rs9701796; and FTO rs9939609) were determined using a real-time PCR reaction and a TaqMan assay. The subjects were divided into quartiles regarding to percentage of excess weight loss (%EWL). The effect of genetic variants on energy and macronutrient intake was evaluated by simple logistic regression, followed by multiple logistic regression.

RESULTS

It was found that subjects in the first and second quartile showed a higher initial body mass index (BMI). Energy and macronutrient intake before and 1 year after RYGB surgery did not differ between the %EWL quartiles. None of gene polymorphisms investigated showed an association with the estimated energy intake 1 year after surgery.

CONCLUSION

In conclusion, the estimate energy and food intake did not predict a greater body weight loss 1 year after RYGB surgery. In addition, the 12 gene polymorphism investigated did not affect the energy intake among female patients. This article is protected by copyright. All rights reserved.

Iron Deficiency - Not Only a Premenopausal Topic After Bariatric Surgery?

Purpose

In our centre, specialized high dose multivitamin supplementation designed to meet the needs of patients after gastric bypass surgery is routinely recommended in the early postoperative period. The aim of the present study was to analyse whether iron supplementation prescribed in clinical practice is sufficient in both sexes and whether multivitamin supplementation standardized for women might potentially lead to iron overload in men.

Materials/Methods

This was a retrospective study covering the period up to 36 months after bariatric surgery. Three groups were compared (men, premenopausal and postmenopausal women). The iron status was evaluated employing serum ferritin concentrations.

Results

A total of 283 patients who had at least one follow-up visit between January 2015 and April 2018 at a specialized academic outpatient centre were included (71 men, 130 premenopausal women, 82 postmenopausal women). Thirty-six months after surgery, 33.3%, 68.4% and 54.5% of the men, pre- and postmenopausal women, respectively, were iron deficient. The preoperative prevalence of excess ferritin levels was 13.7% in premenopausal, 3.0% in postmenopausal women, 5.7% in men and declined in the following months.

Conclusion

Iron deficiency is very common after gastric bypass surgery, and even high dosages of multivitamin and mineral supplements might not be sufficient to prevent the development of iron deficiency. Men, pre- and postmenopausal women differ in their prevalence of iron deficiency which demands adapted iron dosage regimens based on the sex and the age. Iron overload is rare in all observed groups and highest in premenopausal women.

Graphical abstract

Cardiovascular Risk Reduction Following Metabolic and Bariatric Surgery

Cardiovascular disease (CVD) remains a leading cause of morbidity and mortality in developed countries, with worsening pandemics of type 2 diabetes mellitus and obesity as major cardiovascular (CV) risk factors. Clinical trials of nonsurgical obesity treatments have not shown benefits in CVD, although recent diabetes trials have demonstrated major CV benefits. In many retrospective and prospective cohort studies, however, metabolic (bariatric) surgery is associated with substantial and reproducible CVD benefits. Despite a lack of prospective, randomized clinical trials, data suggest metabolic surgery may be the most effective modality for CVD risk reduction, likely through weight loss and weight loss-independent mechanisms.

Obesity and Related Type 2 Diabetes: A Failure of the Autonomic Nervous System Controlling Gastrointestinal Function?

The pandemic spread of obesity and type 2 diabetes is a serious health problem that cannot be contained with common therapies. At present, the most effective therapeutic tool is metabolic surgery, which substantially modifies the gastrointestinal anatomical structure. This review reflects the state of the art research in obesity and type 2 diabetes, describing the probable reason for their spread, how the various brain sectors are involved (with particular emphasis on the role of the vagal system controlling different digestive functions), and the possible mechanisms for the effectiveness of bariatric surgery. According to the writer’s interpretation, the identification of drugs that can modulate the activity of some receptor subunits of the vagal neurons and energy-controlling structures of the central nervous system (CNS), and/or specific physical treatment of cortical areas, could reproduce, non-surgically, the positive effects of metabolic surgery.

Recent advances in the mechanisms underlying the beneficial effects of bariatric and metabolic surgery

Bariatric and metabolic surgery (BMS) is the most effective treatment for obesity, type 2 diabetes and co-morbidities, including nonalcoholic fatty liver disease and nonalcoholic steatohepatitis. The beneficial effects of BMS are beyond the primary goal of gastric restriction and nutrients malabsorption. Roux-en-Y gastric bypass and vertical sleeve gastrectomy are the 2 most commonly performed procedures of BMS. Both surgeries lead to physiologic changes in gastrointestinal tract; subsequently alter bile acids pool and composition, gut microbial activities, gut hormones, and circulating exosomes; and ultimately contribute to the improved glycemic control, insulin sensitivity, lipid metabolism, energy expenditure, and weight loss. The mechanisms underlying the benefits of BMS likely involve the bile acid-signaling pathway mediated mainly by nuclear farnesoid X receptor and the membrane Takeda G protein-coupled receptor, bile acids-gut microbiota interaction, and exosomes. In this review, we focus on recent advances in potential mechanisms and aim to learn novel insights into the molecular mechanisms underlying metabolic disorders.

A Case of Wernicke's Encephalopathy in a Pregnant Woman With a History of Sleeve Gastrectomy

Wernicke’s encephalopathy (WE) is a neurological complication of thiamine deficiency characterized by a triad of acute confusion, ataxia, and ophthalmoplegia. Even though it is most common in chronic alcoholism, an increase in prevalence has been reported recently due to the increased popularity of bariatric surgeries. WE is a known neurological complication after gastric bypass surgery but rarely reported after sleeve gastrectomy. We present a unique case of WE in pregnant women four months after sleeve gastrectomy.

Appetite, the enteroendocrine system, gastrointestinal disease and obesity

The enteroendocrine system is located in the gastrointestinal (GI) tract, and makes up the largest endocrine system in the human body. Despite that, its roles and functions remain incompletely understood. Gut regulatory peptides are the main products of enteroendocrine cells, and play an integral role in the digestion and absorption of nutrients through their effect on intestinal secretions and gut motility. Several peptides, such as cholecystokinin, polypeptide YY and glucagon-like peptide-1, have traditionally been reported to suppress appetite following food intake, so-called satiety hormones. In this review, we propose that, in the healthy individual, this system to regulate appetite does not play a dominant role in normal food intake regulation, and that there is insufficient evidence to wholly link postprandial endogenous gut peptides with appetite-related behaviours. Instead, or additionally, top-down, hedonic drive and neurocognitive factors may have more of an impact on food intake. In GI disease however, supraphysiological levels of these hormones may have more of an impact on appetite regulation as well as contributing to other unpleasant abdominal symptoms, potentially as part of an innate response to injury. Further work is required to better understand the mechanisms involved in appetite control and unlock the therapeutic potential offered by the enteroendocrine system in GI disease and obesity.

Gut Microbiota, Obesity and Bariatric Surgery: Current Knowledge and Future Perspectives

BACKGROUND

There is an urgent need for a better understanding and management of obesity and obesity- associated diseases. It is known that obesity is associated with structural and functional changes in the microbiome.

METHODS

The purpose of this review is to present current evidence from animal and human studies, demonstrating the effects and the potential efficacy of microbiota modulation in improving obesity and associated metabolic dysfunctions.

RESULTS

This review discusses possible mechanisms linking gut microbiota dysbiosis and obesity, since there is a dual interaction between the two of them. Furthermore, comments on bariatric surgery, as a favourable model to understand the underlying metabolic and inflammatory effects, as well as its association with changes in the composition of the gut microbiota, are included. Also, a possible impact of anti-obesity drugs and the novel antidiabetic drugs on the gut microbiota has been briefly discussed.

CONCLUSION

More research is needed to better understand here discussed the association between microbiota modulation and obesity. It is expected that research in this field, in the following years, will lead to a personalized therapeutic approach considering the patient's microbiome, and also give rise to the discovery of new drugs and/or the combination therapies for the management of obesity and obesity-related co-morbidities.

Ultra-Early and Early Changes in Bile Acids and Insulin After Sleeve Gastrectomy Among Obese Patients

BACKGROUND AND OBJECTIVE

In obese patients, sleeve gastrectomy (SG) has shown mixed results on bile acid (BA) values. The aim of our study was to examine the potential ultra-early and early changes of the circulating total BA in relation with the changes of insulin resistance (IR) in obese patients submitted to laparoscopic SG. Materials and Methods: Twenty-four obese subjects were investigated for body mass index (BMI), total fasting BA, insulin, homeostasis model assessment of insulin resistance (HOMA-IR), and leptin before and at 7 and 30 d after SG. Results: After surgery, mean BMI decreased at the first (p < 0.001) and at the second time point (p < 0.001) relative to baseline. Total fasting BA values did not change significantly at 7 d (p = 0.938) and at 30 d (p = 0.289) after SG. No significant changes were found at 7 d (p = 0.194, p = 0.34) and 30 d (p = 0.329, p = 0.151) after surgery regarding fasting insulin and HOMA-IR, respectively. However, a trend of increased total fasting BA and decreased fasting insulin and HOMA- after laparoscopic SG has been found. Negative correlations between total fasting BA and insulin (r = -0.807, p = 0.009), HOMA-IR (r = -0.855, p = 0.014), and blood glucose (r = -0.761, p = 0.047), respectively, were observed at one month after SG. Conclusion: In conclusion, here, we found a lack of significant changes in total fasting BA, insulin, and HOMA-IR ultra-early and early after SG, which precluded us to consider a possible relation between the variations of BA and IR. However, the presence of the tendency for total fasting BA to increase and for insulin and HOMA-IR to decrease, as well as of the negative correlations one month after laparoscopic SG, suggest that this surgery brings about some changes that point towards the existence, and possibly towards the restoration, at least to some extent, of the link between BA and glucose metabolism.

Utilizing Untargeted Ion Mobility-Mass Spectrometry To Profile Changes in the Gut Metabolome Following Biliary Diversion Surgery

Obesity and obesity-related disorders are a global epidemic affecting over 10% of the world's population. Treatment of these diseases has become increasingly challenging and expensive. The most effective and durable treatment for Class III obesity (body mass index ≥35 kg/m²) is bariatric surgery, namely, Roux-en-Y gastric bypass (RYGB) and vertical sleeve gastrectomy. These procedures are associated with increased circulating bile acids, molecules that not only facilitate intestinal fat absorption but are also potent hormones regulating numerous metabolic pathways. We recently reported on a novel surgical procedure in mice, termed distal gallbladder bile diversion to the ileum (GB-IL_dist), that emulates the altered bile flow after RYGB without other manipulations of gastrointestinal anatomy. GB-IL_dist improves oral glucose tolerance in mice made obese with high-fat diet. This is accompanied by fat malabsorption and weight loss, which complicates studying the role of elevated circulating bile acids in metabolic control. A less aggressive surgery in which the gallbladder bile is diverted to the proximal ileum, termed GB-IL_prox, also improves glucose control but is not accompanied by fat malabsorption. To better understand the differential effects achieved by these bile diversion procedures, an untargeted ultraperformance liquid chromatography-ion mobility-mass spectrometry (UPLC-IM-MS) method was optimized for fecal samples derived from mice that have undergone bile diversion surgery. Utilizing the UPLC-IM-MS method, we were able to identify dysregulation of bile acids, short-chain fatty acids, and cholesterol derivatives that contribute to the differential metabolism resulting from these surgeries.

FABP2, LEPR223, LEP656, and FTO Polymorphisms: Effect on Weight Loss 2 Years After Bariatric Surgery

PURPOSE

Differences in weight loss outcomes after bariatric surgery may be related to individual preoperative characteristics. The aim of this study was to evaluate the potential effect of fatty acid binding protein-2 (rs1799883), leptin receptor (LEP223, rs1137101 and LEP656, rs1805094), and fat mass and obesity-related (rs9939609) genotypes on weight loss 2 years after bariatric surgery in Brazilian patients.

MATERIALS AND METHODS

Prospective observational study involving 105 patients (lost to follow-up, 25.7%). In the preoperative period, patients were clinically evaluated and a fasting blood sample for genetic analysis (by real-time DNA amplification technique) was collected. From the patient's medical records, follow-up weight loss (3, 6, 12, 24 months) was obtained. Percentage of excess weight loss (%EWL) was examined by pairwise comparison across the polymorphisms.

RESULTS

At baseline, the mean weight was 127.5 (23.3) kg and age 43.1 (10.9) years old. The %EWL was significant over time (p < 0.01). Only the LEP223 genotype showed association (p < 0.01). Up to 6 months after surgery, no differences were observed. At 12 months, a significant difference (p = 0.03) between AA (n = 19) and GG (n = 34) groups was observed, with 76.5% EWL versus 52.0%, respectively. This difference remained at 24 months. Other genotypes did not present any significant association.

CONCLUSIONS

There is a different evolution of weight loss in carriers of the LEP223 after bariatric surgery. The AA genotype seems to be associated with a higher weight loss. However, this pattern was evident only at 12 months after surgery.

The Effects of Laparoscopic Sleeve Gastrectomy on the Parameters of Leptin Resistance in Obesity

Obesity is a growing public health problem worldwide. Bariatric surgical procedures achieve the most sustainable and efficacious outcomes in the treatment of morbid obesity. However, little is known about the underlying molecular pathways modulated by these surgical interventions. Since leptin resistance is implicated in the pathogenesis of obesity, we herein report the effects of laparoscopic sleeve gastrectomy (LSG) on the serum levels of leptin and leptin receptor, in addition to its overall effect on leptin resistance. This was an interventional and follow-up clinical study. In the first part, patients attending the general surgery outpatient clinics at our university hospital were first stratified according to their Body-Mass Index (BMI) into cases (n = 38) with BMI ≥ 35 who were scheduled to undergo LSG, and controls (n = 75) with a normal BMI. Serum leptin and leptin receptor levels were measured by sandwich ELISA technique. A leptin resistance index was estimated by adjusting leptin to BMI ratio to leptin receptor concentration. In the second part of the study, cases who underwent LSG were followed up one year postoperatively to assess their BMI and serum leptin and leptin receptor levels. Leptin to BMI ratio was significantly higher, while serum leptin receptor was significantly lower, in obese patients compared to controls. This translated into a significantly higher leptin resistance index in obese patients. LSG resulted in a significant reduction of BMI, leptin to BMI ratio, and leptin resistance index, as it significantly increased leptin receptor levels. In conclusion, LSG showed significant decrease in leptin resistance in obese patients after one year. Further studies are needed to determine the clinical impact of this finding on LSG outcomes.

Laparoscopic sleeve gastrectomy versus laparoscopic gastric bypass: A retrospective cohort study

BACKGROUND

There are many reports on short-term outcomes following sleeve gastrectomy, which demonstrate that it has comparable efficacy to gastric bypass. However, there are very few long-term comparative reports. This study compared the outcomes from laparoscopic sleeve gastrectomy (LSG) and laparoscopic gastric bypass (LGB) in a cohort of patients who had surgery in 2011 with a six-year follow up.

MATERIALS AND METHODS

Data on patients who had either LSG or LGB at a single centre in Mohak Bariatric and Robotic Surgery Centre, Indore, M.P. India in 2011 were identified from a database of routinely collected data. This retrospective cohort was analysed for weight loss, resolution of comorbidities and nutritional status over six years. Patients who had revision operations or for whom six-year follow-up data were not available were excluded from the analysis.

RESULTS

154 patients had LGB and 152 had LSG. The six-year follow up rate was 61.7% (n = 95) and 64.5% (n = 98) respectively for LGB and LSG. Percentage of excess bodyweight loss (%EWL) peaked at approximately 70% after two years in the LSG group and after three years in the LGB group. However, after six years %EWL was 61% for LGB and 50% for LSG (p = 0.001). Resolution of type-2 diabetes was more common in the LGB group compared to the LSG group (79% vs 62%, p = 0.126). Resolution of hypertension and dyslipidaemia was similar in both groups at approximately half of patients in each group for each condition. Nutrient deficiencies were found in both groups but were generally more pronounced in the LGB group.

CONCLUSION

LGB is a better operation for weight loss, weight loss maintenance, and resolution of type-2 diabetes than LSG. This is at the expense of an increased incidence of nutrient deficiencies. LSG appears to have greater treatment failure by six years follow up and this should be further investigated.

Seasonal variation of body weight loss after bariatric surgery

Seasonal variations have been described in humans in several variables such as sleep, mood, appetite, food preferences, or body weight. We hypothesized that these variations could also influence the decrease in body weight rate in patients submitted to body weight loss interventions. Thus, here we tested the variations of weight loss according to the time of the year the surgery took place in a group patients (n = 1322) submitted to bariatric surgery in the Hospital Universitari de la Vall d'Hebron in Barcelona (geographical coordinates: 41°25'41″N 2°8'32″E). For the analysis, the percentage of total body weight loss (%TWL), excess body weight loss (%EWL) and percentage of body mass index loss (%BMIL) were calculated at 3 (n = 1255), 6 (n = 1172), 9 (n = 1002), and 12 months (n = 1076) after surgery. For %EWL and %BMIL a statistically significant seasonal variation was detected when the variables were calculated at 3 months, but not at the other times, with more weight loss in summer-fall. However, seasonal variations were not detected for %TWL (p = 0.09). The mean amplitude of the seasonal rhythm for %EWL was of 1.8%, while for the rhythm of %BMIL was 0.7%. Moreover, a second peak was detected in January-February modulating the seasonal rhythm of the two variables. Results confirm seasonal variations in humans and indicate that short term responses to weight loss can be modulated by the time of year.

Fibroblast Growth Factor 15/19: From Basic Functions to Therapeutic Perspectives

Discovered 20 years ago, fibroblast growth factor (FGF)19, and its mouse ortholog FGF15, were the first members of a new subfamily of FGFs able to act as hormones. During fetal life, FGF15/19 is involved in organogenesis, affecting the development of the ear, eye, heart, and brain. At adulthood, FGF15/19 is mainly produced by the ileum, acting on the liver to repress hepatic bile acid synthesis and promote postprandial nutrient partitioning. In rodents, pharmacologic doses of FGF19 induce the same antiobesity and antidiabetic actions as FGF21, with these metabolic effects being partly mediated by the brain. However, activation of hepatocyte proliferation by FGF19 has long been a challenge to its therapeutic use. Recently, genetic reengineering of the molecule has resolved this issue. Despite a global overlap in expression pattern and function, murine FGF15 and human FGF19 exhibit several differences in terms of regulation, molecular structure, signaling, and biological properties. As most of the knowledge originates from the use of FGF19 in murine models, differences between mice and humans in the biology of FGF15/19 have to be considered for a successful translation from bench to bedside. This review summarizes the basic knowledge concerning FGF15/19 in mice and humans, with a special focus on regulation of production, morphogenic properties, hepatocyte growth, bile acid homeostasis, as well as actions on glucose, lipid, and energy homeostasis. Moreover, implications and therapeutic perspectives concerning FGF19 in human diseases (including obesity, type 2 diabetes, hepatic steatosis, biliary disorders, and cancer) are also discussed.

Attenuation of diet-induced hypothalamic inflammation following bariatric surgery in female mice

Background

Exposure of rodents to chronic high-fat diet (HFD) results in upregulation of inflammatory markers and proliferation of microglia within the mediobasal hypothalamus. Such hypothalamic inflammation is associated with metabolic dysfunction, central leptin resistance, and maintenance of obesity. Bariatric surgeries result in long-term stable weight loss and improved metabolic function. However, the effects of such surgical procedures on HFD-induced hypothalamic inflammation are unknown. We sought to characterize the effects of two bariatric surgical procedures, Roux-en-Y gastric bypass (RYGB) and biliary diversion (BD-IL), in female mice with particular emphasis on HFD-induced hypothalamic inflammation and microgliosis.

Methods

RYGB and BD-IL were performed on diet-induced obese (DIO) mice. Quantitative RT-PCR and fluorescent microscopy were used to evaluate hypothalamic inflammatory gene expression and microgliosis. Results were compared to lean (CD), DIO sham-surgerized mice (DIO-SHAM), and dietary weight loss (DIO-Rev) controls.

Results

In female mice, RYGB and BD-IL result in normalization of hypothalamic inflammatory gene expression and microgliosis within 8 weeks of surgery, despite ongoing exposure to HFD. Paralleling these results, the hypothalamic expression levels of the orexigenic neuropeptide Agrp and the anorexic response of surgical mice to exogenous leptin were comparable to lean controls (CD). In contrast, results from DIO-Rev mice were comparable to DIO-SHAM mice, despite transition back to standard rodent show and normalization of weight.

Conclusion

Bariatric surgery attenuates HFD-induced hypothalamic inflammation and microgliosis and restores leptin sensitivity, despite ongoing exposure to HFD.

Evaluation of quality of life, weight loss and comorbidities of patients undergoing bariatric surgery

OBJECTIVE

to assess the efficacy of weight loss, the evolution of comorbidities, the quality of life and the BAROS protocol (Bariatric Analysis and Reporting Outcome System) in the postoperative period of patients undergoing bariatric surgery.

METHODS

we conducted a cross-sectional, quantitative study with 95% true strength (P=0.05), with 103 patients submitted to SLEEVE Vertical Gastrectomy (40) and Roux-en-Y Gastric Bypass (63), from four months after surgery. We carried out the research at the Ambulatory of General Surgery of the Clinics Hospital of the Federal University of Pernambuco, using the BAROS protocol.

RESULTS

the majority of the patients were female (89.3%). The mean age was 44.23 years. The mean percentage loss of excess weight was 69.35%. The mean postoperative follow-up time was 41.87 months (±37.35). The comorbidities with the highest percentage of resolution were sleep apnea (90.2%), diabetes (80.7%) and hypertension (70.8%). The most frequent complications were hair loss (79.6%), nutritional deficiency (37.9%) and anemia (35%). The BAROS protocol demonstrated that patients positively evaluated quality of life in 93.2% of the cases. The Moorehead-Ardelt questionnaire showed that quality of life "improved" or "improved greatly" for 94.1% of patients.

CONCLUSION

bariatric surgery has been shown to be an effective procedure in the treatment of morbid obesity and in the control of comorbidities. Quality of life analysis was evaluated positively through the BAROS protocol.

Metabolic and Bariatric Surgery: An Effective Treatment Option for Obesity and Cardiovascular Disease

Obesity is a chronic and debilitating disease that has become a global epidemic. Especially severe in the Unites States, obesity currently affects almost 40% of the population. Obesity has a strong causal relationship with numerous serious comorbidities that impair quality of life, shorten life expectancy, and carry a major economic burden. Obesity has particular relevance to cardiologists because it contributes directly to several major cardiovascular diseases and, consequently, increases overall cardiovascular mortality. Multiple treatment options are available, but metabolic and bariatric surgery offers the most effective and durable treatment for obesity. Moreover, metabolic and bariatric operations alleviate and often completely eliminate numerous comorbidities, particularly type 2 diabetes and other cardiovascular risk factors, such as hypertension and dyslipidemia. With their low risk of complications and morbidity, metabolic and bariatric operations significantly improve quality of life and overall survival, particularly reducing death due to cardiovascular disease.

Surgical treatment of obesity

Obesity prevalence continues to increase worldwide, as do the numerous chronic diseases associated with obesity, including diabetes, non-alcoholic fatty liver disease, dyslipidemia, and hypertension. The prevalence of bariatric surgery also continues to increase and remains the most effective and sustainable treatment for obesity. Over the last several years, numerous prospective and longitudinal studies have demonstrated the benefits of bariatric surgery on weight loss, mortality, and other chronic diseases. Even though the mechanisms underlying many of these beneficial effects remain poorly understood, surgical management of obesity continues to increase given its unmatched efficacy. In this commentary, we discuss recent clinical advancements as well as several areas needed for future research, including indications for bariatric and metabolic surgery, determination of responders and non-responders, metabolic surgery in non-obese individuals, and the evolving role of bariatric surgery in adolescents.

Metabolic Changes Up to 10 years After Gastric Bypass

OBJECTIVE

The aim of this study was to investigate the lipid and glycemic profiles of patients up to 10 years after Roux-en-Y gastric bypass.

METHOD

A retrospective, longitudinal study was conducted at a multidisciplinary center for the treatment of obesity in the state of São Paulo, Brazil. The study included 150 patients submitted to unbanded laparoscopic Roux-en-Y gastric bypass. The metabolic profile included total cholesterol and fractions, triglycerides, and fasting glucose. The patients were examined before and 3, 6, 12, 24, 48, 72, 96, and 120 months after surgery. Statistical analyses included the generalized estimating equations (GEE) and the Wilcoxon test at a significance level of 5%.

RESULTS

All postoperative fasting glucose, total cholesterol, and triglyceride (p < 0.0001) test results were significantly lower than the preoperative test results. Low-density lipoprotein cholesterol (LDL-c) differed significantly in all but the 120-month follow-up (p = 0.0129). High-density lipoprotein cholesterol (HDL-c) was significantly higher 12, 24, 48, and 72 months after surgery (p < 0.001) and also 120 months after surgery (p = 0.0002).

CONCLUSION

Gastric bypass promoted the control of metabolic diseases inherent to obesity as long as 10 years after surgery.

Novel developments in vagal afferent nutrient sensing and its role in energy homeostasis

Vagal afferent neurons (VANs) play an important role in the control of food intake by signaling nutrient type and quantity to the brain. Recent findings are broadening our view of how VANs impact not only food intake but also energy homeostasis. This review focuses exclusively on studies of the vagus nerve from the past 2 years that highlight major new advancements in the field. We firstly discuss evidence that VANs can directly sense nutrients, and we consider new insights into mechanisms affecting sensing of gastric distension and signaling by gastrointestinal hormones ghrelin and GLP1. We discuss evidence that disrupting vagal afferent signaling increases long-term control of food intake and body weight management, and the importance of this gut-brain pathway in mediating beneficial effects of bariatric surgery. We conclude by highlighting novel roles for vagal afferent neurons in circadian rhythm, thermogenesis, and reward that may provide insight into mechanisms by which VAN nutrient sensing controls long-term control of energy homeostasis.