Analysis of the effect of staple line reinforcement on leaking and bleeding after sleeve gastrectomy from the UK National Bariatric Surgery Registry.

INTRODUCTION: Sleeve gastrectomy (SG) is currently the most frequently performed procedure for obesity worldwide. Staple line reinforcement (SLR) has been suggested as a strategy to reduce the risk of staple line leak or bleeding; however, its use for SG in the United Kingdom (UK) is unknown. This study examined the effect of SLR on the development of postoperative complications from SG using a large national dataset from the UK. METHODS: Patients undergoing either primary or revision SG over 10 years from Jan 2012 to Dec 2021 were identified by the National Bariatric Surgery Registry. Comparative and logistic regression analyses were undertaken to determine the effect of SLR on staple line leak and bleeding. RESULTS: During this time, 14,231 patients underwent SG for whom there were complete data. Of these, 76.5% were female and the median age was 46 years (IQR: 36-53). The rate of surgical complications was 2.3% (n = 219/14,231). The incidence of bleeding was 1.3% (n = 179/14,231) and leak was 1.0% (n = 140/14,231). Over time, the use of SLR of any variety declined significantly from 99.7% in 2012 to 57.3% in 2021 (p < 0.001). Multivariable (adjusted) regression analysis demonstrated that neither the use of nor the type of reinforcement had any effect on the rate of bleeding or leaking. CONCLUSION: SLR for SG has declined in the UK since 2012. There were no differences in staple line leak or bleed with or without reinforcement.

Access to publicly funded weight management services in England using routine data from primary and secondary care (2007-2020): An observational cohort study.

BACKGROUND: Adults living with overweight/obesity are eligible for publicly funded weight management (WM) programmes according to national guidance. People with the most severe and complex obesity are eligible for bariatric surgery. Primary care plays a key role in identifying overweight/obesity and referring to WM interventions. This study aimed to (1) describe the primary care population in England who (a) are referred for WM interventions and (b) undergo bariatric surgery and (2) determine the patient and GP practice characteristics associated with both. METHODS AND FINDINGS: An observational cohort study was undertaken using routinely collected primary care data in England from the Clinical Practice Research Datalink linked with Hospital Episode Statistics. During the study period (January 2007 to June 2020), 1,811,587 adults met the inclusion criteria of a recording of overweight/obesity in primary care, of which 54.62% were female and 20.10% aged 45 to 54. Only 56,783 (3.13%) were referred to WM, and 3,701 (1.09% of those with severe and complex obesity) underwent bariatric surgery. Multivariable Poisson regression examined the associations of demographic, clinical, and regional characteristics on the likelihood of WM referral and bariatric surgery. Higher body mass index (BMI) and practice region had the strongest associations with both outcomes. People with BMI ≥40 kg/m2 were more than 6 times as likely to be referred for WM (10.05% of individuals) than BMI 25.0 to 29.9 kg/m2 (1.34%) (rate ratio (RR) 6.19, 95% confidence interval (CI) [5.99,6.40], p < 0.001). They were more than 5 times as likely to undergo bariatric surgery (3.98%) than BMI 35.0 to 40.0 kg/m2 with a comorbidity (0.53%) (RR 5.52, 95% CI [5.07,6.02], p < 0.001). Patients from practices in the West Midlands were the most likely to have a WM referral (5.40%) (RR 2.17, 95% CI [2.10,2.24], p < 0.001, compared with the North West, 2.89%), and practices from the East of England least likely (1.04%) (RR 0.43, 95% CI [0.41,0.46], p < 0.001, compared with North West). Patients from practices in London were the most likely to undergo bariatric surgery (2.15%), and practices in the North West the least likely (0.68%) (RR 3.29, 95% CI [2.88,3.76], p < 0.001, London compared with North West). Longer duration since diagnosis with severe and complex obesity (e.g., 1.67% of individuals diagnosed in 2007 versus 0.34% in 2015, RR 0.20, 95% CI [0.12,0.32], p < 0.001), and increasing comorbidities (e.g., 2.26% of individuals with 6+ comorbidities versus 1.39% with none (RR 8.79, 95% CI [7.16,10.79], p < 0.001) were also strongly associated with bariatric surgery. The main limitation is the reliance on overweight/obesity being recorded within primary care records to identify the study population. CONCLUSIONS: Between 2007 and 2020, a very small percentage of the primary care population eligible for WM referral or bariatric surgery according to national guidance received either. Higher BMI and GP practice region had the strongest associations with both. Regional inequalities may reflect differences in commissioning and provision of WM services across the country. Multi-stakeholder qualitative research is ongoing to understand the barriers to accessing WM services and potential solutions. Together with population-wide prevention strategies, improved access to WM interventions is needed to reduce obesity levels.

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.

Defining Global Benchmarks in Elective Secondary Bariatric Surgery Comprising Conversional, Revisional, and Reversal Procedures.

OBJECTIVE: To define "best possible" outcomes for secondary bariatric surgery (BS). BACKGROUND: Management of poor response and of long-term complications after BS is complex and under-investigated. Indications and types of reoperations vary widely and postoperative complication rates are higher compared to primary BS. METHODS: Out of 44,884 BS performed in 18 high-volume centers from 4 continents between 06/2013-05/2019, 5,349 (12%) secondary BS cases were identified. Twenty-one outcome benchmarks were established in low-risk patients, defined as the 75th percentile of the median outcome values of centers. Benchmark cases had no previous laparotomy, diabetes, sleep apnea, cardiopathy, renal insufficiency, inflammatory bowel disease, immunosuppression, thromboembolic events, BMI> 50 kg/m2 or age> 65 years. RESULTS: The benchmark cohort included 3143 cases, mainly females (85%), aged 43.8 ±â€Š10 years, 8.4 ±â€Š5.3 years after primary BS, with a BMI 35.2 ±â€Š7 kg/m2. Main indications were insufficient weight loss (43%) and gastro-esophageal reflux disease/dysphagia (25%). 90-days postoperatively, 14.6% of benchmark patients presented ≥1 complication, mortality was 0.06% (n = 2). Significantly higher morbidity was observed in non-benchmark cases (OR 1.37) and after conversional/reversal or revisional procedures with gastrointestinal suture/stapling (OR 1.84). Benchmark cutoffs for conversional BS were ≤4.5% re-intervention, ≤8.3% re-operation 90-days postoperatively. At 2-years (IQR 1-3) 15.6% of benchmark patients required a reoperation. CONCLUSION: Secondary BS is safe, although postoperative morbidity exceeds the established benchmarks for primary BS. The excess morbidity is due to an increased risk of gastrointestinal leakage and higher need for intensive care. The considerable rate of tertiary BS warrants expertise and future research to optimize the management of non-success after BS.

Does bariatric surgery reduce future hospital costs? A propensity score-matched analysis using UK Biobank Study data.

OBJECTIVES: To estimate the hospital costs among persons with obesity undergoing bariatric surgery compared with those without bariatric surgery. METHODS: We analysed the UK Biobank Cohort study linked to Hospital Episode Statistics, for all adults with obesity undergoing bariatric surgery at National Health Service hospitals in England, Scotland, or Wales from 2006 to 2017. Surgery patients were matched with controls who did not have bariatric surgery using propensity scores approach with a ratio of up to 1-to-5 by year. Inverse probability of censoring weighting was used to correct for potential informative censoring. Annual and cumulative hospital costs were assessed for the surgery and control groups. RESULTS: We identified 348 surgical patients (198 gastric bypass, 73 sleeve gastrectomy, 77 gastric banding) during the study period. In total, 324 surgical patients and 1506 matched control participants were included after propensity score matching. Mean 5-year cumulative hospital costs were €11,659 for 348 surgical patients. Compared with controls, surgical patients (n = 324) had significantly higher inpatient expenditures in the surgery year (€7289 vs. €2635, P < 0.001), but lower costs in the subsequent 4 years. The 5-year cumulative costs were €11,176 for surgical patients and €8759 for controls (P = 0.001). CONCLUSIONS: Bariatric surgery significantly increased the inpatient costs in the surgery year, but was associated with decreased costs in the subsequent 4 years. However, any cost savings made up to 4 years were not enough to compensate for the initial surgical expenditure.

Association of bariatric surgery with all-cause mortality and incidence of obesity-related disease at a population level: A systematic review and meta-analysis.

BACKGROUND: Previous clinical trials and institutional studies have demonstrated that surgery for the treatment of obesity (termed bariatric or metabolic surgery) reduces all-cause mortality and the development of obesity-related diseases such as type 2 diabetes mellitus (T2DM), hypertension, and dyslipidaemia. The current study analysed large-scale population studies to assess the association of bariatric surgery with long-term mortality and incidence of new-onset obesity-related disease at a national level. METHODS AND FINDINGS: A systematic literature search of Medline (via PubMed), Embase, and Web of Science was performed. Articles were included if they were national or regional administrative database cohort studies reporting comparative risk of long-term mortality or incident obesity-related diseases for patients who have undergone any form of bariatric surgery compared with an appropriate control group with a minimum follow-up period of 18 months. Meta-analysis of hazard ratios (HRs) was performed for mortality risk, and pooled odds ratios (PORs) were calculated for discrete variables relating to incident disease. Eighteen studies were identified as suitable for inclusion. There were 1,539,904 patients included in the analysis, with 269,818 receiving bariatric surgery and 1,270,086 control patients. Bariatric surgery was associated with a reduced rate of all-cause mortality (POR 0.62, 95% CI 0.55 to 0.69, p < 0.001) and cardiovascular mortality (POR 0.50, 95% CI 0.35 to 0.71, p < 0.001). Bariatric surgery was strongly associated with reduced incidence of T2DM (POR 0.39, 95% CI 0.18 to 0.83, p = 0.010), hypertension (POR 0.36, 95% CI 0.32 to 0.40, p < 0.001), dyslipidaemia (POR 0.33, 95% CI 0.14 to 0.80, p = 0.010), and ischemic heart disease (POR 0.46, 95% CI 0.29 to 0.73, p = 0.001). Limitations of the study include that it was not possible to account for unmeasured variables, which may not have been equally distributed between patient groups given the non-randomised design of the studies included. There was also heterogeneity between studies in the nature of the control group utilised, and potential adverse outcomes related to bariatric surgery were not specifically examined due to a lack of available data. CONCLUSIONS: This pooled analysis suggests that bariatric surgery is associated with reduced long-term all-cause mortality and incidence of obesity-related disease in patients with obesity for the whole operated population. The results suggest that broader access to bariatric surgery for people with obesity may reduce the long-term sequelae of this disease and provide population-level benefits.

Bariatric surgery for patients with type 2 diabetes mellitus requiring insulin: Clinical outcome and cost-effectiveness analyses.

BACKGROUND: Although bariatric surgery is well established as an effective treatment for patients with obesity and type 2 diabetes mellitus (T2DM), there exists reluctance to increase its availability for patients with severe T2DM. The aims of this study were to examine the impact of bariatric surgery on T2DM resolution in patients with obesity and T2DM requiring insulin (T2DM-Ins) using data from a national database and to develop a health economic model to evaluate the cost-effectiveness of surgery in this cohort when compared to best medical treatment (BMT). METHODS AND FINDINGS: Clinical data from the National Bariatric Surgical Registry (NBSR), a comprehensive database of bariatric surgery in the United Kingdom, were extracted to analyse outcomes of patients with obesity and T2DM-Ins who underwent primary bariatric surgery between 2009 and 2017. Outcomes for this group were combined with data sourced from a comprehensive literature review in order to develop a state-transition microsimulation model to evaluate cost-effectiveness of bariatric surgery versus BMT for patients over a 5-year time horizon. The main outcome measure for the clinical study was insulin cessation at 1-year post-surgery: relative risks (RR) summarising predictive factors were determined, unadjusted, and after adjusting for variables including age, initial body mass index (BMI), duration of T2DM, and weight loss. Main outcome measures for the economic evaluation were total costs, total quality-adjusted life years (QALYs), and incremental cost-effectiveness ratio (ICER) at willingness-to-pay threshold of GBP£20,000. A total of 2,484 patients were eligible for inclusion, of which 1,847 had 1-year follow-up data (mean age of 51 years, mean initial BMI 47.2 kg/m2, and 64% female). 67% of patients no longer required insulin at 1-year postoperatively: these rates persisted for 4 years. Roux-en-Y gastric bypass (RYGB) was associated with a higher rate of insulin cessation (71.7%) than sleeve gastrectomy (SG; 64.5%; RR 0.92, confidence interval (CI) 0.86-0.99) and adjustable gastric band (AGB; 33.6%; RR 0.45, CI 0.34-0.60; p < 0.001). When adjusted for percentage total weight loss and demographic variables, insulin cessation following surgery was comparable for RYGB and SG (RR 0.97, CI 0.90-1.04), with AGB having the lowest cessation rates (RR 0.55, CI 0.40-0.74; p < 0.001). Over 5 years, bariatric surgery was cost saving compared to BMT (total cost GBP£22,057 versus GBP£26,286 respectively, incremental difference GBP£4,229). This was due to lower treatment costs as well as reduced diabetes-related complications costs and increased health benefits. Limitations of this study include loss to follow-up of patients within the NBSR dataset and that the time horizon for the economic analysis is limited to 5 years. In addition, the study reflects current medical and surgical treatment regimens for this cohort of patients, which may change. CONCLUSIONS: In this study, we observed that in patients with obesity and T2DM-Ins, bariatric surgery was associated with high rates of postoperative cessation of insulin therapy, which is, in turn, a major driver of overall reductions in direct healthcare cost. Our findings suggest that a strategy utilising bariatric surgery for patients with obesity and T2DM-Ins is cost saving to the national healthcare provider (National Health Service (NHS)) over a 5-year time horizon.

Defining Global Benchmarks in Bariatric Surgery: A Retrospective Multicenter Analysis of Minimally Invasive Roux-en-Y Gastric Bypass and Sleeve Gastrectomy.

OBJECTIVE: To define "best possible" outcomes for bariatric surgery (BS)(Roux-en-Y gastric bypass [RYGB] and sleeve gastrectomy [SG]). BACKGROUND: Reference values for optimal surgical outcomes in well-defined low-risk bariatric patients have not been established so far. Consequently, outcome comparison across centers and over time is impeded by heterogeneity in case-mix. METHODS: Out of 39,424 elective BS performed in 19 high-volume academic centers from 3 continents between June 2012 and May 2017, we identified 4120 RYGB and 1457 SG low-risk cases defined by absence of previous abdominal surgery, concomitant procedures, diabetes mellitus, sleep apnea, cardiopathy, renal insufficiency, inflammatory bowel disease, immunosuppression, anticoagulation, BMI>50 kg/m and age>65 years. We chose clinically relevant endpoints covering the intra- and postoperative course. Complications were graded by severity using the comprehensive complication index. Benchmark values were defined as the 75th percentile of the participating centers' median values for respective quality indicators. RESULTS: Patients were mainly females (78%), aged 38±11 years, with a baseline BMI 40.8 ±â€Š5.8 kg/m. Over 90 days, 7.2% of RYGB and 6.2% of SG patients presented at least 1 complication and no patients died (mortality in nonbenchmark cases: 0.06%). The most frequent reasons for readmission after 90-days following both procedures were symptomatic cholelithiasis and abdominal pain of unknown origin. Benchmark values for both RYGB and SG at 90-days postoperatively were 5.5% Clavien-Dindo grade ≥IIIa complication rate, 5.5% readmission rate, and comprehensive complication index ≤33.73 in the subgroup of patients presenting at least 1 grade ≥II complication. CONCLUSION: Benchmark cutoffs targeting perioperative outcomes in BS offer a new tool in surgical quality-metrics and may be implemented in quality-improvement cycle.ClinicalTrials.gov Identifier NCT03440138.

Increased radiation dose and projected radiation-related lifetime cancer risk in patients with obesity due to projection radiography.

PURPOSE: Primarily to evaluate the radiation dose delivered to patients with obesity in projection radiography and its relationship to the patient's size. A secondary purpose is to estimate the subsequent projected radiation-related lifetime cancer risk to patients with obesity compared to normal-weight patients. METHOD AND MATERIAL: Data from 1964 patients from a bariatric clinic in the UK were reviewed with the relevant permission. 630 patients were identified to have a projection radiography history and were included in the study. Patients' dose area product (DAP) data were collected for all projection radiography. Multiple exams in one day including a single DAP reading and exams with no records of DAP and exposure factors were excluded. Correlations were calculated and data analysed to yield the third quartile for each examination using STATA 14. Absorbed doses were generated from PCXMC simulation, utilising DAP data from this study and the UK national diagnostic reference level (NDRL), to calculate the effective risk for patients with obesity compared to patients with normal-weight. RESULTS: Patients with obesity received higher DAPs for all examinations included in this study compared to NDRL. Abdominal and lumbar spine radiographs DAPs were the highest (17.6 and 30.31 Gy cm2) compared to the NDRL (2.5 and 4 Gy cm2). Only moderate to low correlations were found between patient's size and DAPs in the abdomen and chest radiographs. The projected radiation-related lifetime cancer risk for patients with obesity is up to 153% higher than for adult patients with normal weight. CONCLUSION: Patients with obesity receive higher DAPs than normal-weight adults which may be in excess of that expected due to their size. Therefore, radiation-related lifetime cancer risk is increased in patients with obesity as a result of medical radiation exposures. This indicates more dose optimisation research is needed in this group of patients to reduce dose rate and variation.

A Core Outcome Set for the Benefits and Adverse Events of Bariatric and Metabolic Surgery: The BARIACT Project.

BACKGROUND: Bariatric and metabolic surgery is used as a treatment for patients with severe and complex obesity. However, there is a need to improve outcome selection and reporting in bariatric surgery trials. A Core Outcome Set (COS), an agreed minimum set of outcomes reported in all studies of a specific condition, may achieve this. Here, we present the development of a COS for BARIAtric and metabolic surgery Clinical Trials-the BARIACT Study. METHODS AND FINDINGS: Outcomes identified from systematic reviews and patient interviews informed a questionnaire survey. Patients and health professionals were surveyed three times and asked to rate the importance of each item on a 1-9 scale. Delphi methods provided anonymised feedback to participants. Items not meeting predefined criteria were discarded between rounds. Remaining items were discussed at consensus meetings, held separately with patients and professionals, where the COS was agreed. Data sources identified 2,990 outcomes, which were used to develop a 130-item questionnaire. Round 1 response rates were moderate but subsequently improved to above 75% for other rounds. After rounds 2 and 3, 81 and 14 items were discarded, respectively, leaving 35 items for discussion at consensus meetings. The final COS included nine items: "weight," "diabetes status," "cardiovascular risk," "overall quality of life (QOL)," "mortality," "technical complications of the specific operation," "any re-operation/re-intervention," "dysphagia/regurgitation," and "micronutrient status." The main limitation of this study was that it was based in the United Kingdom only. CONCLUSIONS: The COS is recommended to be used as a minimum in all trials of bariatric and metabolic surgery. Adoption of the COS will improve data synthesis and the value of research data. Future work will establish methods for the measurement of the outcomes in the COS.

What are important outcomes of bariatric surgery? An in-depth analysis to inform the development of a core outcome set and a comparison between the views of surgeons and other health professionals (the BARIACT study).

BACKGROUND: Outcome reporting in bariatric surgery needs uniformity. A core outcome set is an agreed minimum set of outcomes reported in all studies of a particular condition, but members of the bariatric multidisciplinary team might value outcomes differently. The aim of this study was to summarise existing outcome reporting in bariatric surgery, to inform the development of a core outcome set, and to compare outcomes selected as important by type of health professional. METHODS: Outcomes reported in randomised controlled trials (RCTs) and large non-randomised studies, identified by a systematic review, were listed verbatim. Frequency of outcome reporting and uniformity of definition were assessed. A questionnaire to rate the importance of each outcome was completed by members of the bariatric multidisciplinary team. Responses to each item were scored as 1 (not essential) to 9 (absolutely essential). We ranked outcomes according to percentage deemed important (7-9) and according to respondents by type of health professional. FINDINGS: We identified 1088 individual outcomes from 90 studies (39 RCTs), grouped them into health domains, and presented them as a questionnaire with 131 items to 489 multidisciplinary team members. Most outcomes (n=920, 85%) were reported only once. The largest outcome domain was surgical complications, and 432 outcomes (42%) corresponded to an adverse event. Only a quarter of outcomes (n=461) were defined, and were often contradictory. For questionnaire responders (n=164, response rate 33·5%), most were surgeons (n=80, 48·8%), followed by dietitians (n=31, 18·9%), nurses (n=24, 14·6%), physicians (n=12, 7·3%), and others (n=16, 9·9%). Improvement in diabetes was the top outcome for all health professionals. Seven of the surgeon's top ten outcomes were adverse events, compared with three for other health professionals. Groups valued a measure of weight differently (third vs 15th for other health professionals and surgeons, respectively). INTERPRETATION: This study shows that the assessment of bariatric surgery focuses largely on adverse events and resolution of comorbidity, but that reporting is inconsistent and ill-defined. Substantial variation between the views of surgeons and those of other health professionals was evident. The next step is to provide feedback to participants and to survey their views again before a final consensus meeting to produce a core outcome set for the Benefits and Adverse events in BARIAtric surgery Clinical Trials (BARIACT) as a solution to this problem. FUNDING: National Institute for Health Research (NIHR), and the NIHR Health Technology Assessment programme. This work was also undertaken with the support of the MRC ConDuCT-II Hub (Collaboration and innovation for Difficult and Complex randomised controlled Trials In Invasive procedures, MR/K025643/1).

The use of adjustable gastric bands for management of severe and complex obesity.

BACKGROUND: Obesity levels in the UK have reached a sustained high and ∼4% of the population would be candidates for bariatric surgery based upon current UK NICE guidelines, which has important implications for Clinical Commissioning Groups. SOURCES OF DATA: Summary data from Cochrane systematic reviews, randomized controlled trials (RCTs) and cohort studies. AREAS OF AGREEMENT: Currently, the only treatment that offers significant and durable weight loss for those with severe and complex obesity is surgery. Three operations account for 95% of all bariatric surgery in the UK, but the NHS offers surgery to only a small fraction of those who could benefit. Laparoscopic adjustable gastric banding (gastric banding) has potentially the lowest risk and up-front costs of the three procedures. AREAS OF CONTROVERSY: Reliable Level 1 evidence of the relative effectiveness of the operations is lacking. GROWING POINTS: As a point intervention, weight loss surgery together with the chronic disease management strategy for obesity can prevent significant future disease and mortality, and the NHS should embrace both. AREAS TIMELY FOR DEVELOPING RESEARCH: Better RCT evidence is needed including clinical effectiveness and economic analysis to answer the important question 'which is the best of the three operations most frequently performed?' This review considers the current evidence for gastric banding for the treatment of severe and complex obesity.

An evaluation of operative self-assessment by UK postgraduate trainees.

BACKGROUND: Surgeons in training undertake procedure-based assessment (PBA) with their trainers. Time pressures limit when this occurs. Self-assessment would provide additional opportunities but requires evaluation of your own skills and knowledge. AIM: To investigate the validity of a self-assessment PBA in the operating theatre and evaluate learning needs and change in practice identified. METHODS: In a prospective study, postgraduate UK trainees performed a self-assessment PBA after formally reflecting on appendicectomy surgery. Later, they performed their usual external assessment PBA on the same case and outcomes were compared. Learning outcomes were analysed independently by two trainers. RESULTS: There were 25 trainees (14 males), of age 29 years (25-33). They had performed a median of five previous appendicectomies (2-21) after a median three years of speciality training (range 1-4). There were no significant differences in global summary scores, trainee satisfaction or learning outcomes between external and self-assessment PBAs. Construct validity of the self-assessment PBA was demonstrated. The self-assessment PBA was more likely to identify non-technical skills. CONCLUSION: Our results suggest self-assessment PBA is valid for formative assessment. It identified a wide range of learning outcomes. Self-assessment PBA would help trainees maximise every learning opportunity and practice self-assessment skills.

Assessing economic investment required to scale up bariatric surgery capacity in England: a health economic modelling analysis.

OBJECTIVES: To quantify the economic investment required to increase bariatric surgery (BaS) capacity in National Health Service (NHS) England considering the growing obesity prevalence and low provision of BaS in England despite its high clinical effectiveness. DESIGN: Data were included for the patients with obesity who were eligible for BaS. We used a decision-tree approach including four distinct steps of the patient pathway to capture all associated resource use. We estimated total costs according to the current capacity (current scenario) and three BaS scaling up strategies over a time horizon of 20 years (projected scenario): maximising NHS capacity (strategy 1), maximising NHS and private sector capacity (strategy 2) and adding infrastructure to NHS capacity to cover the entire prevalent and incident obesity populations (strategy 3). SETTING: BaS centres based in NHS and private sector hospitals in England. MAIN OUTCOME MEASURES: Number of BaS procedures (including revision surgery), cost (GBP) and resource utilisation over 20 years. RESULTS: At current capacity, the number of BaS procedures and the total cost over 20 years were estimated to be 140 220 and £1.4 billion, respectively. For strategy 1, these values were projected to increase to 157 760 and £1.7 billion, respectively. For strategy 2, the values were projected to increase to 232 760 and £2.5 billion, respectively. Strategy 3 showed the highest increase to 564 784 and £6.4 billion, respectively, with an additional 4081 personnel and 49 facilities required over 20 years. CONCLUSIONS: The expansion of BaS capacity in England beyond a small proportion of the eligible population will likely be challenging given the significant upfront economic investment and additional requirement of personnel and infrastructure.

Core Set of Patient-Reported Outcome Measures for Measuring Quality of Life in Clinical Obesity Care.

PURPOSE: The focus of measuring success in obesity treatment is shifting from weight loss to patients' health and quality of life. The objective of this study was to select a core set of patient-reported outcomes and patient-reported outcome measures to be used in clinical obesity care. MATERIALS AND METHODS: The Standardizing Quality of Life in Obesity Treatment III, face-to-face hybrid consensus meeting, including people living with obesity as well as healthcare providers, was held in Maastricht, the Netherlands, in 2022. It was preceded by two prior multinational consensus meetings and a systematic review. RESULTS: The meeting was attended by 27 participants, representing twelve countries from five continents. The participants included healthcare providers, such as surgeons, endocrinologists, dietitians, psychologists, researchers, and people living with obesity, most of whom were involved in patient representative networks. Three patient-reported outcome measures (patient-reported outcomes) were selected: the Impact of Weight on Quality of Life-Lite (self-esteem) measure, the BODY-Q (physical function, physical symptoms, psychological function, social function, eating behavior, and body image), and the Quality of Life for Obesity Surgery questionnaire (excess skin). No patient-reported outcome measure was selected for stigma. CONCLUSION: A core set of patient-reported outcomes and patient-reported outcome measures for measuring quality of life in clinical obesity care is established incorporating patients' and experts' opinions. This set should be used as a minimum for measuring quality of life in routine clinical practice. It is essential that individual patient-reported outcome measure scores are shared with people living with obesity in order to enhance patient engagement and shared decision-making.

The mechanical properties of human adipose tissues and their relationships to the structure and composition of the extracellular matrix.

Adipose tissue (AT) expansion in obesity is characterized by cellular growth and continuous extracellular matrix (ECM) remodeling with increased fibrillar collagen deposition. It is hypothesized that the matrix can inhibit cellular expansion and lipid storage. Therefore, it is important to fully characterize the ECM's biomechanical properties and its interactions with cells. In this study, we characterize and compare the mechanical properties of human subcutaneous and omental tissues, which have different physiological functions. AT was obtained from 44 subjects undergoing surgery. Force/extension and stress/relaxation data were obtained. The effects of osmotic challenge were measured to investigate the cellular contribution to tissue mechanics. Tissue structure and its response to tensile strain were determined using nonlinear microscopy. AT showed nonlinear stress/strain characteristics of up to a 30% strain. Comparing paired subcutaneous and omental samples (n = 19), the moduli were lower in subcutaneous: initial 1.6 ± 0.8 (means ± SD) and 2.9 ± 1.5 kPa (P = 0.001), final 11.7 ± 6.4 and 32 ± 15.6 kPa (P < 0.001), respectively. The energy dissipation density was lower in subcutaneous AT (n = 13): 0.1 ± 0.1 and 0.3 ± 0.2 kPa, respectively (P = 0.006). Stress/relaxation followed a two-exponential time course. When the incubation medium was exchanged for deionized water in specimens held at 30% strain, force decreased by 31%, and the final modulus increased significantly. Nonlinear microscopy revealed collagen and elastin networks in close proximity to adipocytes and a larger-scale network of larger fiber bundles. There was considerable microscale heterogeneity in the response to strain in both cells and matrix fibers. These results suggest that subcutaneous AT has greater capacity for expansion and recovery from mechanical deformation than omental AT.

Effect of source of funding on weight loss up to 3 years after gastric banding.

BACKGROUND: Laparoscopic adjustable gastric banding (LAGB) is a popular choice for patients seeking weight loss surgery. Since behavioural change appears to play a role in weight loss outcomes we postulated that publicly funded patients might not do as well as self-payers. This series examines the effect of public funding versus self-pay on patients undergoing LAGB over 1, 2 and 3 years. METHODS: Consecutive non-randomised cohort series of patient undergoing LAGB over 5 years (September 2003 to December 2008) in a single unit. Age, sex, funding route, body mass index (BMI) and complications were recorded. Per cent excess weight loss (EWL) and the Reinhold criterion for success (proportion achieving 50 % EWL) were assessed. RESULTS: Ninety-nine patients were publicly funded, and 250 patients were self-payers. Initial BMI was significantly higher in publicly funded patients (46.6 vs. 42.3 kg/m(2), p < 0.001) with a higher proportion of males (22.2 vs. 6.0 %, p < 0.001). Mean % EWL was significantly less for publicly funded patients at 1 year (38.1 vs. 53.5 %, p < 0.001) and 2 years (49.6 vs. 64.1 %, p < 0.001), but not at 3 years (59.7 vs. 61.8 %, p = 0.784). Fewer publicly funded patients achieved 50 % EWL at 1 year (24.5 vs. 50.2 %, p < 0.001), but with no significant difference at 2 years (54.8 vs. 67.0 %, p = 0.140) or 3 years (55.2 vs. 66.0 %, p = 0.349). CONCLUSIONS: Self-pay patients initially achieved more % EWL and greater success in reaching 50 % EWL after LAGB, but this difference was not maintained. The results suggest that patient motivation, using self-pay as a surrogate marker, may affect early results, but the operation itself is the main determinant of weight loss at 3 years.

Bariatric surgery provision in response to the COVID-19 pandemic: retrospective cohort study of a national registry.

BACKGROUND: When surgery resumed following the outbreak of the COVID-19 pandemic, guidelines recommended the prioritization of patients with greater obesity-related co-morbidities and/or higher body mass index. OBJECTIVE: The aim of this study was to record the effect of the pandemic on total number, patient demographics, and perioperative outcomes of elective bariatric surgery patients in the United Kingdom. SETTING AND METHODS: The United Kingdom National Bariatric Surgical Registry was used to identify patients who underwent elective bariatric surgery during the pandemic (1 yr from April 1, 2020). Characteristics of this group were compared with those of a pre-pandemic cohort. Primary outcomes were case volume, case mix, and providers. National Health Service cases were analyzed for baseline health status and perioperative outcomes. Fisher exact, χ2, and Student t tests were used as appropriate. RESULTS: The total number of cases decreased to one third of pre-pandemic volume (8615 to 2930). The decrease in operating volume varied, with 36 hospitals (45%) experiencing a 75%-100% reduction. Cases performed in the National Health Service fell from 74% to 53% (P < .0001). There was no change in baseline body mass index (45.2 ± 8.3 kg/m2 from 45.5 ± 8.3 kg/m2; P = .23) or prevalence of type 2 diabetes (26% from 26%; P = .99). Length of stay (median 2 d) and surgical complication rate (1.4% from 2.0%; relative risk = .71; 95% CI .45-1.12; P = .13) were unchanged. CONCLUSIONS: In the context of a dramatic reduction in elective bariatric surgery due to the COVID-19 pandemic, patients with more severe co-morbidities were not prioritized for surgery. These findings should inform preparation for future crises.

Development of a Bariatric Surgery Core Data Set for an International Registry.

PURPOSE: Bariatric and metabolic surgery is an effective treatment for severe and complex obesity; however, robust long-term data comparing operations is lacking. Clinical registries complement clinical trials in contributing to this evidence base. Agreement on standard data for bariatric registries is needed to facilitate comparisons. This study developed a Core Registry Set (CRS) - core data to include in bariatric surgery registries globally. MATERIALS AND METHODS: Relevant items were identified from a bariatric surgery research core outcome set, a registry data dictionary project, systematic literature searches, and a patient advisory group. This comprehensive list informed a questionnaire for a two-round Delphi survey with international health professionals. Participants rated each item's importance and received anonymized feedback in round 2. Using pre-defined criteria, items were then categorized for voting at a consensus meeting to agree the CRS. RESULTS: Items identified from all sources were grouped into 97 questionnaire items. Professionals (n = 272) from 56 countries participated in the round 1 survey of which 45% responded to round 2. Twenty-four professionals from 13 countries participated in the consensus meeting. Twelve items were voted into the CRS including demographic and bariatric procedure information, effectiveness, and safety outcomes. CONCLUSION: This CRS is the first step towards unifying bariatric surgery registries internationally. We recommend the CRS is included as a minimum dataset in all bariatric registries worldwide. Adoption of the CRS will enable meaningful international comparisons of bariatric operations. Future work will agree definitions and measures for the CRS including incorporating quality-of-life measures defined in a parallel project.

Bariatric surgery, novel glucose-lowering agents, and insulin for type 2 diabetes and obesity: Bayesian network meta-analysis of randomized controlled trials.

BACKGROUND: This network meta-analysis aimed to compare the effects of bariatric surgery, novel glucose-lowering agents (SGLT2i, GLP1RA, DPP4i), and insulin for patients with type 2 diabetes mellitus (T2DM) and obesity. METHODS: Four databases were searched from inception to April 2023 to identify randomized controlled trials (RCTs) comparing bariatric surgery, SGLT2i, GLP1RA, DPP4i, insulin, and/or placebo/usual care among patients with T2DM and obesity in the achievement of HbA1c < 7.0 per cent within one year, and 12-month changes in HbA1c and body weight. RESULTS: A total of 376 eligible RCTs (149 824 patients) were analysed. Bariatric surgery had significantly higher rates of achieving HbA1c < 7.0 per cent than SGLT2i (RR = 2.46, 95 per cent c.i. = 1.28, 4.92), DPP4i (RR = 2.59, 95 per cent c.i. = 1.36, 5.13), insulin (RR = 2.27, 95 per cent c.i. = 1.18, 4.58) and placebo/usual care (RR = 4.02, 95 per cent c.i. = 2.13, 7.93), but had no statistically significant difference from GLP1RA (RR = 1.73, 95 per cent c.i. = 0.91, 3.44), regardless of oral (RR = 1.33, 95 per cent c.i. = 0.66, 2.79) or injectable (RR = 1.75, 95 per cent c.i. = 0.92, 3.45) administration. Significantly more GLP1RA patients achieved HbA1c < 7.0 per cent than other non-surgical treatments. Bariatric surgery had the greatest reductions in HbA1c (∼1 per cent more) and body weight (∼15 kg more) at 12 months. Among novel glucose-lowering medications, GLP1RA was associated with greater reductions in HbA1c than SGLT2i (-0.39 per cent, 95 per cent c.i. = -0.55, -0.22) and DPP4i (-0.51 per cent, 95 per cent c.i. = -0.64, -0.39) at 12 months, while GLP1RA (-1.74 kg, 95 per cent c.i. = -2.48, -1.01) and SGLT2i (-2.23 kg, 95 per cent c.i. = -3.07, -1.39) showed greater reductions in body weight than DPP4i at 12 months. CONCLUSION: Bariatric surgery showed superiority in glycaemic control and weight management compared to non-surgical approaches. GLP1RA administered by oral or injectable form demonstrated reduced HbA1c and body weight at 12 months, and was preferable over other non-surgical treatments among patients with T2DM and obesity. PROSPERO REGISTRATION NO: CRD42020201507.