Bariatric-Metabolic Surgery Utilisation in Patients With and Without Diabetes: Data from the IFSO Global Registry 2015-2018

Comparing Safety and Efficacy Outcomes of Gastric Bypass and Sleeve Gastrectomy in Patients With Type 2 Diabetes Mellitus: A Systematic Review and Meta-Analysis

Sleeve Gastrectomy (SG) could be done by the removal of a big portion of the stomach, leading to reduced amounts of food taken as a result of the smaller stomach size. In contrast, Roux-en-Y Gastric Bypass (RYGB) can be done by creating a small stomach pouch and rerouting a part of the small intestine, employing combined mechanisms of restriction and malabsorption to limit food intake and modify nutrient absorption. Our aim is to identify the most effective and safest surgical intervention for individuals with both Type 2 Diabetes Mellitus (T2DM) and obesity, considering both short and long-term outcomes. We will assess participants undergoing either SG or RYGB to determine the optimal surgical approach. We made a thorough search of PubMed, Cochrane Library, Scopus, and Web of Science databases up to November 2023. Our focus was on randomized controlled trials (RCTs) comparing the safety and efficacy of RYGB and SG in T2DM regarding any extractable data. We excluded studies of other designs, such as cohorts, case reports, case series, reviews, in vitro studies, postmortem analyses, and conference abstracts. Utilizing Review Manager 5.4, we performed a meta-analysis, combining risk ratios (RR) with a 95% confidence interval (CI) conducted for binary outcomes, while mean with SD and 95% CI are pooled for the continuous ones. The total number of participants in our study is 4,148 patients. Our analysis indicates superior outcomes in the group undergoing RYGB surgery compared to the SG group (RR = 0.76, 95% (CI) (0.66 to 0.88), P = 0.0002). The pooled data exhibited homogeneity (P = 0.51, I2 = 0%) after employing the leave-one-out method. For the 1-3 year period, six studies involving 332 patients with T2DM yielded non-significant results (RR = 0.83, 95% CI (0.66 to 1.06), P = 0.14) with homogeneity (P = 0.24, I2 = 28%). Conversely, the 5-10 year period, with six studies comprising 728 DM patients, demonstrated significant results (RR = 0.69, 95% CI (0.56 to 0.85), P = 0.14) and homogeneity (P = 0.84, I2 = 0%). In terms of total body weight loss, our findings indicate significantly higher weight loss with RYGB (mean difference (MD) = -6.13, 95% CI (-8.65 to -3.6), P > 0.00001). However, pooled data exhibited considerable heterogeneity (P > 0.00001, I2 = 93%). Subgroup analyses for the 1-3 year period (five studies, 364 DM patients) and 5-10 year period (six studies, 985 DM patients) also revealed significant differences favoring RYGB, with heterogeneity observed in both periods (1-3 years: P > 0.00001, I2 = 95%; 5-10 years: P = 0.001, I2 = 75%). RYGB demonstrated significant long-term improvement in diabetes remission and superior total body weight loss compared to SG. While no notable differences were observed in other efficacy outcomes, safety parameters require further investigation. no significant distinctions were found in any of the safety outcomes: hypertension (HTN), high-density lipoprotein (HDL), hyperlipidemia, fasting blood glucose, vomiting, low-density lipoprotein (LDL), and total cholesterol. Further research is essential to comprehensively assess safety outcomes for both surgical approaches.

Bariatric surgery induces pancreatic cell transdifferentiation as indicated by single-cell transcriptomics in Zucker diabetic rats

AIMS

Bariatric surgery results in rapid recovery of glucose control in subjects with type 2 diabetes mellitus. However, the underlying mechanisms are still largely unknown. The present study aims to clarify how bariatric surgery modifies pancreatic cell subgroup differentiation and transformation in the single-cell RNA level.

METHODS

Male, 8-week-old Zucker diabetic fatty (ZDF) rats with obesity and diabetes phenotypes were randomized into sleeve gastrectomy (Sleeve, n = 9), Roux-en-Y gastric bypass (RYGB, n = 9), and Sham (n = 7) groups. Two weeks after surgery, the pancreas specimen was further analyzed using single-cell RNA-sequencing technique.

RESULTS

Two weeks after surgery, compared to the Sham group, the metabolic parameters including fasting plasma glucose, plasma insulin, and oral glucose tolerance test values were dramatically improved after RYGB and Sleeve procedures (p < .05) as predicted. In addition, RYGB and Sleeve groups increased the proportion of pancreatic β cells and reduced the ratio of α cells. Two multiple hormone-expressing cells were identified, the Gcg+/Ppy + and Ins+/Gcg+/Ppy + cells. The pancreatic Ins+/Gcg+/Ppy + cells were defined for the first time, and further investigation indicates similarities with α and β cells, with unique gene expression patterns, which implies that pancreatic cell transdifferentiation occurs following bariatric surgery.

CONCLUSIONS

For the first time, using the single-cell transcriptome map of ZDF rats, we reported a comprehensive characterization of the heterogeneity and differentiation of pancreatic endocrinal cells after bariatric surgery, which may contribute to the underlying mechanisms. Further studies will be needed to elucidate these results.

Routine gastric suspension technique in single-port sleeve gastrectomy procedure

BACKGROUND

Due to limited technical demand, single-port sleeve gastrectomy (SPSG) is a feasible laparoscopic technique for sleeve gastrectomy (SG). Nonetheless, difficulties exist when performing the single-port technique, and in this study, we aim to describe a slight maneuver that can improve the SPSG procedure.

METHODS

Patients who underwent laparoscopic SG between January 2022 and May 2023 at our hospital were included. The patients were classified into two groups: (1) SPSG and (2) multiple-port SG (MPSG). The parameters for this analysis were the patients' age, gender, weight, body mass index (BMI), conversion rate, drainage placement, 30-day readmission rate, and postoperative complications. Postoperative one-month and three-month percentages of total weight loss (%TWL) were calculated and compared.

RESULTS

171 patients were included in this study: (1) the SPSG group (n = 96) and (2) the MPSG group (n = 75). No statistically significant difference was observed within the preoperative (age, gender, height, weight, and BMI) and the perioperative parameters between SPSG and MPSG (operation time, drainage placement, 30-day readmission) (p > 0.05). Per Clavien-Dindo's grading, two patients in the SPSG group suffered grade 1 complications; for the MPSG group, one patient sustained grade 2 and another suffered grade 3b complication. No statistical significance was observed on the %TWL between the two groups (p > 0.05).

CONCLUSION

Our study found that performing SPSG in specific patient is feasible and non-inferior when compared to the MPSG. Further studies will be needed to elucidate better the efficacy and safety of performing SPSG.

How to address weight regain after bariatric surgery in an individualized way

Bariatric surgery is the most effective obesity treatment. As a chronic and progressive disease, weight loss response to surgery will vary individually. Thus, insufficient weight loss or regain can happen after surgery, but they lack a standard definition. There are different mechanisms underlying weight regain and/or insufficient weight loss, such as genetics, maladaptive eating behaviors, and the inadequate choice of index operations, among others. Patients with weight regain or insufficient weight loss should be submitted to an individualized and comprehensive evaluation by a multidisciplinary team. This may help identify the causes and direct the appropriate treatment individually. Options for patients with insufficient weight loss and/or weight regain following bariatric surgery include repair of postoperative complications, conversion into another operation, endoscopic therapies with inconsistent outcomes, and dietary/behavioral counseling. Revision and conversion surgeries have higher complication rates than primary operations. Although there is no standard pharmacological regimen for that indication, the new agents seem efficient and safe to promote the loss of the regained weight and even be adjunctive to selected patients before they reach the plateau. This review aims to summarize the knowledge of the best approach for patients with weight regain/insufficient weight loss and suggests an algorithm to customize the approach and therapeutic options after bariatric surgery.

Machine Learning Prediction of Iron Deficiency Anemia in Chinese Premenopausal Women 12 Months after Sleeve Gastrectomy

Premenopausal women, who account for more than half of patients for bariatric surgery, are at higher risk of developing postoperative iron deficiency anemia (IDA) than postmenopausal women and men. We aimed at establishing a machine learning model to evaluate the risk of newly onset IDA in premenopausal women 12 months after sleeve gastrectomy (SG). Premenopausal women with complete clinical records and undergoing SG were enrolled in this retrospective study. Newly onset IDA after surgery, the main outcome, was defined according to the age- and gender-specific World Health Organization criteria. A linear support vector machine model was developed to predict the risk of IDA after SG with the top five important features identified during feature selection. Four hundred and seven subjects aged 31.0 (Interquartile range (IQR): 26.0-36.0) years with a median follow-up period of 12 (IQR 7-13) months were analyzed. They were divided into a training set and a validation set with 285 and 122 individuals, respectively. Preoperative ferritin, age, hemoglobin, creatinine, and fasting C-peptide were included. The model showed moderate discrimination in both sets (area under curve 0.858 and 0.799, respectively, p < 0.001). The calibration curve indicated acceptable consistency between observed and predicted results in both sets. Moreover, decision curve analysis showed substantial clinical benefits of the model in both sets. Our machine learning model could accurately predict newly onset IDA in Chinese premenopausal women with obesity 12 months after SG. External validation was required before the model was used in clinical practice.

Remission of Type 2 Diabetes Mellitus (T2DM) after Sleeve Gastrectomy (SG), One-Anastomosis Gastric Bypass (OAGB), and Roux-en-Y Gastric Bypass (RYGB): A Systematic Review

Background and Objectives: The three most widely performed bariatric surgeries are Roux-en-Y gastric bypass (RYGB), sleeve gastrectomy (SG), and one-anastomosis gastric bypass (OAGB). Aside from the benefits of weight loss, current findings suggest that these procedures can also induce remission of T2DM (type 2 diabetes mellitus). There are limited data that directly compare these three procedures. This study aims to compare the short-term and long-term remission of T2DM after RYGB, SG, and OAGB. Materials and Methods: Three databases (Embase, PubMed, and Cochrane) were searched for randomised controlled trials, prospective studies, and retrospective studies that compared the effects of RYGB, SG, and OAGB on T2DM remission. Studies published between 2001 and 2022 were analysed. Only patients with T2DM and who had primary bariatric surgery were included. Results: After applying the inclusion and exclusion criteria, seven articles were included in the review. It was found that all three procedures had comparable T2DM remission. RYGB was noted to have the highest complication rate when compared to SG and OAGB. Importantly, it was noted that other predictive factors such as age, duration of diabetes, baseline HbA1c, BMI, and use of antidiabetic medication play a crucial role in T2DM remission. Conclusions: This systematic literature review confirms the existing data that all three bariatric surgeries induce remission of T2DM. Increasing in popularity, OAGB had comparable outcomes to RYGB and SG in inducing T2DM remission. In addition to the choice of bariatric surgery, there are other independent predictive factors that have an impact on T2DM remission. Further studies with larger sample sizes, longer follow-up periods, and studies that control confounding factors are required in this field.

A Video-Based Review of Important Technical Concepts in the Nissen-Sleeve Gastrectomy

PURPOSE

The development of gastroesophageal reflux disease (GERD) is a commonly encountered scenario after sleeve gastrectomy. A recently reported technical amendment to incorporate a Nissen fundoplication is discussed in this multimedia article focussing on optimising outcomes and reducing complications.

MATERIALS AND METHODS

An intraoperative video has been edited to demonstrate the Nissen-Sleeve Gastrectomy and important technical considerations in its technical performance.

RESULTS

Gastrolysis is performed proximally from 6 cm proximal to the pylorus. Routine full mediastinal mobilisation of the oesophagus (5 cm) is completed. Cruroplasty is routinely performed. A short Nissen fundoplication is completed calibrated on a 37 French bougie and then sleeve gastrectomy is performed. Our team's experience suggests that careful manipulation of the fundus and using reproducible measurements of the fundus are key to completing the fundoplication whilst minimising complications. A control test with mobilisation of the bougie through the wrap is recommended at the end of the procedure.

CONCLUSION

The Nissen-Sleeve Gastrectomy, as presented in this video, is safe and has good short-term efficacy outcomes. Longer term and randomised studies are ongoing.

Obesity surgery: Which procedure should we choose and why?

In the 70years that bariatric surgery has existed, many different surgical procedures have been developed. Four procedures are officially accepted by all learned societies: adjustable gastric banding (AGB), sleeve gastrectomy (SG), Roux-en-Y gastric bypass (RYGB) and bilio-pancreatic diversion (BPD). Gastric banding has the lowest short-term surgical risk, but it has the highest re-operation rate. Compared to SG, RYGB presents about twice the risk of early complications. Late complications seem equivalent between the two procedures but studies with follow-up>10years are rarer for SG. SG has become the most commonly performed bariatric procedure worldwide, followed by RYGB, which is still the standard. BPD remains very marginal but the omega gastric bypass, an alternative technique that is still under evaluation, now competes with RYGB. The effectiveness of these different procedures on weight loss remains difficult to compare. SG and RYGB seem to be equivalent for weight loss results and remission of type-2 diabetes (T2DM). Their results are superior to AGB. Procedures that result in greater lengths of intestinal bypass (bilio-pancreatic diversion, omega bypass) seem to have a greater weight-loss effect but are burdened by more side effects. In conclusion, the choice of a procedure is conditioned firstly by the benefit-risk ratio and in relation to patient-related parameters, particularly the body mass index (BMI) and co-morbidities. Long-term results are also linked to factors other than surgery and in particular patient behavioral factors. Obesity is a chronic disease that indicates the need for real long-term medical and surgical management.

Bariatric-metabolic surgery for NHS patients with type 2 diabetes in the United Kingdom National Bariatric Surgery Registry

AIM

Bariatric-metabolic surgery is approved by the National Institute of Health and Care Excellence (NICE) for people with severe obesity and type 2 diabetes (T2DM) (including class 1 obesity after 2014). This study analysed baseline characteristics, disease severity and operations undertaken in people with obesity and T2DM undergoing bariatric-metabolic surgery in the UK National Health Service (NHS) compared to those without T2DM.

METHODS

Baseline characteristics, trends over time and operations undertaken were analysed for people undergoing primary bariatric-metabolic surgery in the NHS using the National Bariatric Surgical Registry (NBSR) for 11 years from 2009 to 2019. Clinical practice before and after the publication of the NICE guidance (2014) was examined. Multivariate logistic regression was used to determine associations with T2DM status and the procedure undertaken.

RESULTS

14,948/51,715 (28.9%) participants had T2DM, with 10,626 (71.1%) on oral hypoglycaemics, 4322 (28.9%) on insulin/other injectables, and with T2DM diagnosed 10+ years before surgery in 3876 (25.9%). Participants with T2DM, compared to those without T2DM, were associated with older age (p < 0.001), male sex (p < 0.001), poorer functional status (p < 0.001), dyslipidaemia (OR: 3.58 (CI: 3.39-3.79); p < 0.001), hypertension (OR: 2.32 (2.19-2.45); p < 0.001) and liver disease (OR: 1.73 (1.58-1.90); p < 0.001), but no difference in body mass index was noted. Fewer people receiving bariatric-metabolic surgery after 2015 had T2DM (p < 0.001), although a very small percentage increase of those with class I obesity and T2DM was noted. Gastric bypass was the commonest operation overall. T2DM status was associated with selection for gastric bypass compared to sleeve gastrectomy (p < 0.001).

CONCLUSION

NHS bariatric-metabolic surgery is used for people with T2DM much later in the disease process when it is less effective. National guidance on bariatric-metabolic surgery and data from multiple RCTs have had little impact on clinical practice.

Risk of fracture following gastric surgery for benign and malignant conditions: A study level pooled analysis of population-based cohort studies

BACKGROUND

Metabolic changes may occur following gastric surgery, which has been reported to contribute to bone loss, osteoporosis and even bone fracture. However, the evidence regarding the relationship between gastric surgery for benign and malignant conditions and risk of fracture is controversial. This study was conducted with the aim to evaluate whether gastric surgery is associated with a high risk of fracture.

METHODS

Major electronic databases were searched from inception through October 2021 for population-based cohort studies investigating the associations between gastric surgery (including bariatric gastric surgeries and surgeries for gastric benign and malignant gastric tumors) and risk of fracture compared with controls. Pooled relative risks (RRs) with 95% confidence intervals (CIs) were derived using the random-effects Mantel-Haenszel model. Multiple subgroup analyses and sensitivity analyses were carried out to test sources of heterogeneity stratified by various study characteristics and the robustness of the results.

RESULTS

A total of 14 studies comprising 693134 individuals were identified for analysis. The RR for the risk of fracture in people undergoing gastric surgery was 1.45 [95% confidence interval (CI) 1.23 - 1.72; I^{2 =} 95.8%; P < 0.001] compared with that in control populations, among which the fracture sites of upper limb, spine, lower limb, pelvis and hip showed consistent significant results (all P < 0.05), whereas nonsignificant associations was noted for other fracture sites. Significant associations were also observed for patients having total or subtotal gastrectomy (RR 2.22, 95% CI 1.66 to 3.00), gastric bypass (RR 1.48, 95% CI 1.26 to 1.74), and a similar trend was observed for preserved passage procedures (including sleeve gastrectomy, gastric banding, vertical banded gastroplasty and other procedures that preserved the passage through the duodenum and proximal small bowel, in contrast to gastric bypass), though the difference did not reach statistically significant (RR 1.10, 95% CI 0.95 to 1.26). An evident increased risk in the age range from 40-59 years was observed (40-49 years: RR 1.36, 95% CI 1.19-1.55; 50-59 years: RR 2.48, 95% CI 1.58-3.90).

CONCLUSION

From this large pooled analysis of population-based cohort studies, evidence supports that fracture risk is increased in gastric surgery survivors compared with the control population. Early prevention and effective intervention strategies of bone fracture should be taken from clinicians and health policy makers.

CLINICAL TRIAL REGISTRATION

PROSPERO (https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=291394), identifier CRD42021291394.

Carbamazepine Therapy After Bariatric Surgery: Eight Sleeve Gastrectomy Cases and Review of the Literature

Bariatric surgery modifies the anatomy and physiology of the gastrointestinal tract. Carbamazepine (CBZ) is an anticonvulsant with multiple neuropsychiatric indications. Given CBZ physicochemical properties and narrow therapeutic index, bariatric surgery may potentially introduce clinically significant changes in CBZ oral absorption and bioavailability. In this communication, we describe eight patients undergoing sleeve gastrectomy (SG) and treated with CBZ, including therapeutic drug monitoring (TDM) and dosage adjustments at different timeframes before vs. after the surgery (< 3, 4-6, and 7-12 months post-SG), as well as clinical outcomes. We then provide a review of the available literature on CBZ therapy among bariatric patients, concluding with a mechanistic analysis of the results. Four of the eight patients presented with decreased post-SG CBZ levels, and two of them also experienced significant worsening of their previously well-controlled disease. Overall, altered CBZ levels are likely for at least a year after SG. Clinical recommendations include consultation with a clinical pharmacist, careful clinical monitoring, and periodic TDM after (vs. before) the bariatric surgery.

B1 Vitamin Deficiency After Bariatric Surgery, Prevalence, and Symptoms: a Systematic Review and Meta-analysis

B1 deficiency is a very prevalent complication of bariatric surgery. This study reviews prevalence and symptoms of B1 vitamin deficiency after bariatric surgery. PubMed, Scopus, and Web of Science published were searched up to 10 Feb 2022, with the following keywords: Roux-en-Y gastric bypass, one anastomosis gastric bypass, Omega bypass, Mini bypass, Bariatric surgery OR Bariatric surgery, metabolic surgery, Weight loss surgery, Classic gastric bypass, Loop gastric bypass, Gastric Bypass, thiamine OR thiamin, beriberi, B1. A total of 11 studies examining 1494 patients were included in this meta-analysis. Twenty-seven percent of patients who underwent bariatric surgeries experience vitamin B1 deficiency. Thiamine supplements should be prescribed for the patients for the rest of their lives, and also standard post-surgery follow-ups are necessary in terms of monitoring dietary factors.

Can we abandon foregut exclusion for an ideal and safe metabolic surgery?

Foregut (foregut exclusions) and hindgut (rapid transit of nutrients to the distal intestine) theories are the most commonly used explanations for the metabolic improvements observed after metabolic surgeries. However, several procedures that do not comprise duodenal exclusions, such as sleeve with jejunojejunal bypass, ileal interposition, and transit bipartition and sleeve gastrectomy were found to have similar diabetes remission rates when compared with duodenal exclusion procedures, such as gastric bypass, biliopancreatic diversion with duodenal switch, and diverted sleeve with ileal interposition. Moreover, the complete exclusion of the proximal intestine could result in the malabsorption of several important micronutrients. This article reviews commonly performed procedures, with and without foregut exclusion, to better comprehend whether there is a critical need to include foregut exclusion in metabolic surgery.

Comparable Effects of Sleeve Gastrectomy and Roux-en-Y Gastric Bypass on Basal Fuel Metabolism and Insulin Sensitivity in Individuals with Obesity and Type 2 Diabetes

AIM

Bariatric surgery improves insulin sensitivity and glucose tolerance in obese individuals with type 2 diabetes (T2D), but there is a lack of data comparing the underlying metabolic mechanisms after the 2 most common surgical procedures Roux-en-Y gastric bypass surgery (RYGB) and sleeve gastrectomy (SG). This study was designed to assess and compare the effects of RYGB and SG on fuel metabolism in the basal state and insulin sensitivity during a two-step euglycemic glucose clamp.

MATERIALS AND METHODS

16 obese individuals with T2D undergoing either RYGB (n = 9) or SG (n = 7) were investigated before and 2 months after surgery, and 8 healthy individuals without obesity and T2D served as controls. All underwent a 2 h basal study followed by a 5 h 2-step hyperinsulinemic euglycemic glucose clamp at insulin infusion rates of 0.5 and 1.0 mU/kg LBM/min.

RESULTS

RYGB and SG induced comparable 15% weight losses, normalized HbA1c, fasting glucose, fasting insulin, and decreased energy expenditure. In parallel, we recorded similar increments (about 100%) in overall insulin sensitivity (M-value) and glucose disposal and similar decrements (about 50%) in endogenous glucose production and FFA levels during the clamp; likewise, basal glucose and insulin concentrations decreased proportionally.

CONCLUSION

Our data suggest that RYGB and SG improve basal fuel metabolism and two-step insulin sensitivity in the liver, muscle, and fat and seem equally favourable when investigated 2 months after surgery. This trial is registered with NCT02713555.

Managing the Unpredictable: Mechanistic Analysis and Clinical Recommendations for Lamotrigine Treatment after Bariatric Surgery

Bariatric surgery may alter the absorption and overall bioavailability of oral drugs. Lamotrigine is a major antiepileptic and mood stabilizer, that its use after bariatric surgery has not yet been studied. In this article, we provide a thorough mechanistic analysis of the effects of bariatric surgery on multiple mechanisms important for the absorption, bioavailability and overall pharmacokinetics of lamotrigine. Attributable to its pharmacokinetic properties and drug characteristics, the use of lamotrigine after bariatric surgery may be challenging. The complex situation in which some mechanisms may lead to increased drug exposure (e.g., decreased metabolism, weight loss) while others to its decrease (e.g., hampered dissolution/solubility, decreased gastric volume), may result in lowered, unchanged, or enhanced lamotrigine plasma levels after the surgery. We conclude with a set of clinical recommendations for lamotrigine treatment after bariatric surgery, aiming to allow better patient care, and emphasizing the extra caution that needs to be taken with these patients.

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

Background

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

Methods

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

Results

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

Conclusion

OAGB offers comparable metabolic control through weight loss and T2DM remission to RYGB and SG whilst minimising perioperative complications.

Registration number: CRD42020199779 (https:// www.crd.york.ac.uk/PROSPERO)

Graphical abstract

Prevalence of Peripheral Polyneuropathy Before and After Roux-en-Y Gastric Bypass and Sleeve Gastrectomy

PURPOSE

Peripheral polyneuropathy (PPN) can occur in diabetes mellitus (DM), obesity, and after bariatric surgery (BS). We decided to evaluate PPN prevalence before (PreBS-PPN) and after BS (PostBS-PPN) and to look for variables that may be independently associated with both.

METHODS

In this cross-sectional study, we evaluated 1467 participants with obesity and without DM before and 10.4 ± 6.8 months after Roux-en-Y gastric bypass (RYGB) or sleeve gastrectomy (SG). The Michigan Neuropathy Screening Instrument and the International Physical Activity Questionnaire were used to define the presence of PPN and the Metabolic Equivalent Task (MET) spent per week, respectively. Using Poisson regression models with a robust estimator, the prevalence of PreBS-PPN and PostBS-PPN was analyzed as dependent variables.

RESULTS

Prevalence of PostBS-PPN (10.5%) was lower than PreBS-PPN (20.4%, p < 0.001), with a prevalence of 12.7% post-RYGB and 8.4% post-SG (p = 0.072). In the univariate analysis, PreBS-PPN was associated with post-menopausal status (PMS), older age, and taller height. In twelve regression models, we found an independent association of PreBS-PPN with older age, PMS, and taller height. PostBS-PPN prevalence was associated with a higher fasting glycemia and stature, and a lower MET on univariate analysis, and with higher fasting glycemia, stature and RYGB in four multivariate regression models.

CONCLUSION

PPN occurs frequently in subjects with obesity without DM and is lower after BS. SG is not likely to be harmful in the development of neuropathy. Studies of PPN incidence and persistence after BS should clarify these factors.

Formulation and interpretation of the Chinese Guidelines for Surgical Treatment of Obesity and Type 2 Diabetes Mellitus

Obesity and related metabolic diseases have become one of the world's most serious public health problems. Bariatric surgery has gone through a long and difficult development process, from being rejected to gradually recognized, then widely accepted, and finally becoming the "gold standard" for the treatment of morbid obesity with metabolic diseases. Procedures have constantly been improving and evolving as the concept of bariatric surgery has been reappraised. The comparison and selection of different procedures, the emergence of new technologies and treatment methods, and the in-depth study of the mechanism of metabolic weight loss surgery are effectively promoting the rapid development of bariatric surgery. This article looks at both the 2014 and 2019 editions of the Guidelines for Diagnosis and Treatment of Obesity and Type 2 Diabetes Mellitus from the Chinese Society of Metabolic and Bariatric Surgery (CSMBS), its review the development of bariatric surgery, and it describes surgical indications and contraindications, the mechanism of weight loss, and tailored selection of the surgical procedure in order to serve as a reference.