To Örebro University

BACKGROUND: Laparoscopic sleeve gastrectomy (LSG) has gained increasing popularity worldwide, yet concerns persist regarding the development of gastroesophageal reflux disease (GERD) postoperatively.

OBJECTIVES: This study aimed to evaluate the influence of technical aspects of LSG, specifically bougie size and distance from the pylorus to resection line edge, on the risk of developing symptomatic GERD within 2years following surgery.

SETTING: Data from the Scandinavian Obesity Surgery Registry (SOReg) and the National Prescribed Drug Register were utilized for this analysis.

METHODS: A retrospective observational study was conducted encompassing all LSG patients in Sweden between 2012 and 2020 who did not receive preoperative proton pump inhibitor (PPI) prescriptions. Patients were categorized based on bougie size and pyloric distance. Regular PPI use, defined as a dispensed prescription of more than 300 tablets per year, was employed as a proxy measure of symptomatic GERD and was compared between the groups.

RESULTS: The study included 7,435 patients with complete data on dispensed PPI prescription both preoperatively and throughout the 2-year follow-up period. Information on bougie size and pyloric distance was available for 97.4% and 84.9%, respectively. Narrower bougie size and greater pyloric distance were associated with increased risk of regular PPI use postsurgery. Advanced age and female sex were independent risk factors for post-LSG regular PPI use, while initial body mass index (BMI), total weight loss (%TWL), and comorbidities showed no significant associations.

CONCLUSIONS: Using a narrow bougie and initiating resection at a greater distance from the pylorus were associated with higher risk of symptomatic de novo GERD following LSG.

Background: Laparoscopic sleeve gastrectomy (LSG) as a primary bariatric procedure has gained increasing popularity world-wide. However, controversies still exist regarding several operative aspects, such as the optimal diameter of thesleeve and the optimal distance from the pylorus to the edge of the resection line, and whether these aspects haveeffects on weight-loss results and the risk to develop postoperative complications.

Objective: The aim of this study was to compare weight-loss results and the incidence of postoperative complications betweensleeve with different diameters measured in bougie size and with different distances from the pylorus to the edge ofthe resection line measured in centimeter.

Setting: Nationwide registry-based study.

Method: This study is an analysis of sleeve gastrectomy performed in Sweden between 2012 and 2019. Data were collectedfrom Scandinavian Obesity Surgery Registry (SOReg). Patients with bougie size 30-32 and 35-36 and patients withdistance from pylorus 1-4 cm, 5 cm, 6-8 cm were identified and compared regarding weight-loss results and the riskto develop postoperative complications.

Results: 9,360 patients were included. Follow-up rate was 96% at day 30, 78.8% at one year and 50% at two years. Bothbougie size 30-32 compared to 35-36 and distance from the pylorus 1-4 cm compared to 5 cm were associated withsignificant higher weight-loss at one and two years. No difference in the risk for early or late complications was seenbetween bougie size groups 30-32 and 35-36. Resection starting 1-4 cm from the pylorus compared to 5 cm was as-sociated with higher risk for overall early postoperative complications (OR 1.46 (1.17-1.82, P=.001)), but there wasno significant difference in the risk to develop late complication at 1 and 2 years. No difference in the leak rate andin the risk to develop stricture was seen between different Bougie sizes, nor distances from the Pylorus.

Conclusion: Using a smaller Bougie size and starting the resection closer to the pylorus was associated with better maximumweight-loss. Closer resection to the Pylorus, but not Bougie size was associated with increased risk for early postop-erative complications after sleeve gastrectomy.

BACKGROUND: The optimal sleeve diameter and distance from the pylorus to the edge of the resection line in laparoscopic sleeve gastrectomy (LSG) remain controversial.

OBJECTIVES: To evaluate the influence of bougie size and antral resection distance from the pylorus on postoperative complications and weight-loss results in LSG.

SETTING: Nationwide registry-based study.

METHODS: This study included all LSGs performed in Sweden between 2012 and 2019. Data were obtained from the Scandinavian Obesity Surgery Registry. Reference bougie size of 35-36 Fr and an antral resection distance of 5 cm from the pylorus were compared to narrower bougie size (30-32 Fr), shorter distances (1-4 cm), and extended distances (6-8 cm) from the pylorus in assessing postoperative complications and weight loss as the outcomes of LSG. RESULTS: The study included 9,360 patients with postoperative follow-up rates of 96%, 79%, and 50% at 30 days, 1 year, and 2 years, respectively. Narrow bougie and short antral resection distance from the pylorus were significantly associated with increased postoperative weight loss. Bougie size was not associated with increased early or late complications. However, short antral resection distance was associated with high risk of overall early complications [odds ratio: 1.46 (1.17-1.82, P = .001)], although no impact on late complications at 1 and 2 years was observed.

CONCLUSIONS: Using a narrow bougie and initiating resection closer to the pylorus were associated with greater maximum weight loss. Although a closer resection to the pylorus was associated with an increased risk of early postoperative complications, no association was observed with the use of narrow bougie for LSG.

OBJECTIVE: The aim of this study was to determine long-term changes in pharmacological treatment of type 2 diabetes after primary Roux-en-Y gastric bypass (RYGB) surgery, in patients with and without pharmacological treatment of diabetes preoperatively.

SUMMARY OF BACKGROUND DATA: Several studies have shown that gastric bypass has good effect on diabetes, at least in the short-term. This study is a nationwide cohort study using Swedish registers, with basically no patients lost to follow-up during up to 7 years after surgery.

METHODS: The effect of RYGB on type 2 diabetes drug treatment was evaluated in this nationwide matched cohort study. Participants were 22,047 adults with BMI ≥30 identified in the nationwide Scandinavian Surgical Obesity Registry, who underwent primary RYGB between 2007 and 2012. For each individual, up to 10 general population comparators were matched on birth year, sex, and place of residence. Prescription data were retrieved from the nationwide Swedish Prescribed Drug Register through September 2015. Incident use of pharmacological treatment was analyzed using Cox regression.

RESULTS: Sixty-seven percent of patients with pharmacological treatment of type 2 diabetes before surgery were not using diabetes drugs 2 years after surgery and 61% of patients were not pharmacologically treated up to 7 years after surgery. In patients not using diabetes drugs at baseline, there were 189 new cases of pharmacological treatment of type 2 diabetes in the surgery group and 2319 in the matched general population comparators during a median follow-up of 4.6 years (incidence: 21.4 vs 27.9 per 10,000 person-years; adjusted hazard ratio 0.77, 95% confidence interval 0.67-0.89; P < 0.001).

CONCLUSIONS: Gastric bypass surgery not only induces remission of pharmacological treatment of type 2 diabetes but also protects from new onset of pharmacological diabetes treatment. The effect seems to persist in most, but not all, patients over 7 years of follow-up.

IMPORTANCE: Bariatric surgery is a life-changing treatment for patients with severe obesity, but little is known about its association with interpersonal relationships.

OBJECTIVES: To investigate if relationship status is altered after bariatric surgery.

DESIGN, SETTING, AND PARTICIPANTS: Changes in relationship status after bariatric surgery were examined in 2 cohorts: (1) the prospective Swedish Obese Subjects (SOS) study, which recruited patients undergoing bariatric surgery from September 1, 1987, to January 31, 2001, and compared their care with usual nonsurgical care in matched obese control participants; and (2) participants from the Scandinavian Obesity Surgery Registry (SOReg), a prospective, electronically captured register that recruited patients from January 2007 through December 2012 and selected comparator participants from the general population matched on age, sex, and place of residence. Data was collected in surgical departments and primary health care centers in Sweden. The current analysis includes data collected up until July 2015 (SOS) and December 2012 (SOReg). Data analysis was completed from June 2016 to December 2017.

MAIN OUTCOMES AND MEASURES: In the SOS study, information on relationship status was obtained from questionnaires. In the SOReg and general population cohort, information on marriage and divorce was obtained from the Swedish Total Population Registry.

RESULTS: The SOS study included 1958 patients who had bariatric surgery (of whom 1389 [70.9%] were female) and 1912 matched obese controls (of whom 1354 [70.8%] were female) and had a median (range) follow-up of 10 (0.5-20) years. The SOReg cohort included 29 234 patients who had gastric bypass surgery (of whom 22 131 [75.6%] were female) and 283 748 comparators from the general population (of whom 214 342 [75.5%] were female), and had a median (range) follow-up of 2.9 (0.003-7.0) years. In the SOS study, the surgical patients received gastric banding (n = 368; 18.8%), vertical banded gastroplasty (n = 1331; 68.0%), or gastric bypass (n = 259; 13.2%); controls received usual obesity care. In SOReg, all 29 234 surgical participants received gastric bypass surgery. In the SOS study, bariatric surgery was associated with increased incidence of divorce/separation compared with controls for those in a relationship (adjusted hazard ratio [aHR] = 1.28; 95% CI, 1.03-1.60; P =.03) and increased incidence of marriage or new relationship (aHR = 2.03; 95% CI, 1.52-2.71; P <.001) in those who were unmarried or single at baseline. In the SOReg and general population cohort, gastric bypass was associated with increased incidence of divorce compared with married control participants (aHR = 1.41; 95% CI, 1.33-1.49; P <.001) and increased incidence of marriage in those who were unmarried at baseline (aHR = 1.35; 95% CI, 1.28-1.42; P <.001). Within the surgery groups, changes in relationship status were more common in those with larger weight loss.

CONCLUSIONS AND RELEVANCE: In addition to its association with obesity comorbidities, bariatric surgery-induced weight loss is also associated with changes in relationship status.

BACKGROUND: The long-term effects of bariatric surgery on the mental health of adolescents with severe obesity remain uncertain. We aimed to describe the prevalence of psychiatric health-care visits and filled prescription psychiatric drugs among adolescents with severe obesity undergoing bariatric surgery in the 5 years preceding surgery and throughout the first 10 years after surgery, and to draw comparisons with matched adolescents in the general population.

METHODS: Adolescents with severe obesity and who underwent bariatric surgery were identified through the Scandinavian Obesity Surgery Registry. We included adolescents who had bariatric surgery between 2007 and 2017 and were younger than 21 years at time of surgery. Each adolescent patient was matched with ten adolescents from the general population by age, sex, and county of residence. Specialist psychiatric care and filled psychiatric prescriptions were retrieved from nationwide data registers. FINDINGS: 1554 adolescents (<21 years) with severe obesity underwent bariatric surgery between 2007 and 2017, 1169 (75%) of whom were female. At time of surgery, the mean age was 19·0 years [SD 1·0], and the mean BMI was 43·7 kg/m2 (SD 5·5). 15 540 adolescents from the general population were matched with adolescents in the surgery group. 5 years before the matched index date, 95 (6·2%) of 1535 surgery patients and 370 (2·5%) of 14 643 matched adolescents had a psychiatric health-care visit (prevalence difference 3·7%; 95% CI 2·4-4·9), whereas 127 (9·8%) of 1295 surgery patients and 445 (3·6%) of 12 211 matched adolescents filled a psychiatric drug prescription (prevalence difference 6·2%; 95% CI 4·5-7·8). The year before the matched index date, 208 (13·4%) of 1551 surgery patients and 844 (5·5%) of 15 308 matched adolescents had a psychiatric health-care visit (prevalence difference 7·9%; 95% CI 6·2-9·6), whereas 319 (20·6%) of 1551 surgery patients and 1306 (8·5%) of 15 308 matched adolescents filled a psychiatric drug prescription (prevalence difference 12·0%; 10·0-14·1). The prevalence difference in psychiatric health-care visits peaked 9 years after the matched index date (12·0%; 95% CI 9·0-14·9), when 119 (17·6%) of 675 surgery patients and 377 (5·7%) of 6669 matched adolescents had a psychiatric health-care visit. The prevalence difference in filled psychiatric drug prescription was highest 10 years after the matched index date (20·4%; 15·9-24·9), when 171 (36·5%) of 469 surgery patients and 739 (16·0%) of 4607 matched adolescents filled a psychiatric drug prescription. The year before the matched index date, 19 (1·2%) of 1551 surgery patients and 155 (1·0%) of 15304 matched adolescents had a health-care visit associated with a substance use disorder diagnosis (mean difference 0·2%, 95% CI -0·4 to 0·8). 10 years after the matched index date, the prevalence difference had increased to 4·3% (95% CI 2·3-6·4), when 24 (5·1%) of 467 surgery patients and 37 (0·8%) of 4582 matched adolescents had a health-care visit associated with a substance use disorder diagnosis.

INTERPRETATION: Psychiatric diagnoses and psychiatric drug prescriptions were more common among adolescents with severe obesity who would later undergo bariatric surgery than among matched adolescents from the general population. Both groups showed an increase in prevalence in psychiatric diagnoses and psychiatric drug prescriptions leading up to the time of surgery, but the rate of increase in the prevalence was higher among adolescents with severe obesity than among matched adolescents. With the exception of health-care visits for substance use disorders, these prevalence trajectories continued in the 10 years of follow-up. Realistic expectations regarding mental health outcomes should be set preoperatively.

BACKGROUND: Several studies have addressed short-term admission rates after bariatric surgery. However, studies on long-term admission rates are few and population based studies are even scarcer.

OBJECTIVE: The aim of this study was to assess short- and long-term admission rates for gastrointestinal surgery after gastric bypass in Sweden compared with admission rates in the general population.

SETTING: Swedish healthcare system.

METHODS: The surgery cohort consisted of adults with body mass index≥35 identified in the Scandinavian Obesity Surgery Registry (n = 28,331; mean age 41 years; 76% women; Roux-en-Y gastric bypass performed 2007-2012). For each individual, up to 10 comparators from the general population were matched on birth year, sex, and place of residence (n = 274,513). The primary outcome was inpatient admissions due to gastrointestinal surgery retrieved from the National Patient Register through December 31, 2014. Conditional hazard ratios (HR) were estimated using Cox regression.

RESULTS: All-cause admission rates were 6.5%, 21.4%, and 65.9% during 30 days, 1 year, and 6 years after surgery, respectively. The corresponding rates for gastrointestinal surgery were 1.8%, 6.8%, and 24.4%. Compared with that of the general population, there was an increased risk of all-cause hospital admission at 1 year (HR 2.6 [2.5-2.6]) and 6 years (HR 2.7 [2.6-2.7]). The risk of hospital admission for any gastrointestinal surgical procedure was greatly increased throughout the study period (HR 8.6 [8.4-8.9]). Female sex, psychiatric disease, and low education were risk factors.

CONCLUSION: We found a significant risk of admission to hospital over>6 years after gastric bypass surgery.

Background: Severe obesity is a global public health threat of growing proportions. Accurate models to predict severe postoperative complications could be of value in the preoperative assessment of potential candidates for bariatric surgery. So far, traditional statistical methods have failed to produce high accuracy. We aimed to find a useful machine learning (ML) algorithm to predict the risk for severe complication after bariatric surgery.

Methods: We trained and compared 29 supervised ML algorithms using information from 37,811 patients that operated with a bariatric surgical procedure between 2010 and 2014 in Sweden. The algorithms were then tested on 6250 patients operated in 2015. We performed the synthetic minority oversampling technique tackling the issue that only 3% of patients experienced severe complications.

Results: Most of the ML algorithms showed high accuracy (>90%) and specificity (>90%) in both the training and test data. However, none of the algorithms achieved an acceptable sensitivity in the test data. We also tried to tune the hyperparameters of the algorithms to maximize sensitivity, but did not yet identify one with a high enough sensitivity that can be used in clinical praxis in bariatric surgery. However, a minor, but perceptible, improvement in deep neural network (NN) ML was found.

Conclusion: In predicting the severe postoperative complication among the bariatric surgery patients, ensemble algorithms outperform base algorithms. When compared to other ML algorithms, deep NN has the potential to improve the accuracy and it deserves further investigation. The oversampling technique should be considered in the context of imbalanced data where the number of the interested outcome is relatively small.

BACKGROUND: Obesity is one of today's most visible public health problems worldwide. Although modern bariatric surgery is ostensibly considered safe, serious complications and mortality still occur in some patients.

OBJECTIVE: This study aimed to explore whether serious postoperative complications of bariatric surgery recorded in a national quality registry can be predicted preoperatively using deep learning methods.

METHODS: Patients who were registered in the Scandinavian Obesity Surgery Registry (SOReg) between 2010 and 2015 were included in this study. The patients who underwent a bariatric procedure between 2010 and 2014 were used as training data, and those who underwent a bariatric procedure in 2015 were used as test data. Postoperative complications were graded according to the Clavien-Dindo classification, and complications requiring intervention under general anesthesia or resulting in organ failure or death were considered serious. Three supervised deep learning neural networks were applied and compared in our study: multilayer perceptron (MLP), convolutional neural network (CNN), and recurrent neural network (RNN). The synthetic minority oversampling technique (SMOTE) was used to artificially augment the patients with serious complications. The performances of the neural networks were evaluated using accuracy, sensitivity, specificity, Matthews correlation coefficient, and area under the receiver operating characteristic curve.

RESULTS: In total, 37,811 and 6250 patients were used as the training data and test data, with incidence rates of serious complication of 3.2% (1220/37,811) and 3.0% (188/6250), respectively. When trained using the SMOTE data, the MLP appeared to have a desirable performance, with an area under curve (AUC) of 0.84 (95% CI 0.83-0.85). However, its performance was low for the test data, with an AUC of 0.54 (95% CI 0.53-0.55). The performance of CNN was similar to that of MLP. It generated AUCs of 0.79 (95% CI 0.78-0.80) and 0.57 (95% CI 0.59-0.61) for the SMOTE data and test data, respectively. Compared with the MLP and CNN, the RNN showed worse performance, with AUCs of 0.65 (95% CI 0.64-0.66) and 0.55 (95% CI 0.53-0.57) for the SMOTE data and test data, respectively.

CONCLUSIONS: MLP and CNN showed improved, but limited, ability for predicting the postoperative serious complications after bariatric surgery in the Scandinavian Obesity Surgery Registry data. However, the overfitting issue is still apparent and needs to be overcome by incorporating intra- and perioperative information.

BACKGROUND: Prediction of diabetes remission is an important topic in the evaluation of patients with type 2 diabetes (T2D) before bariatric surgery. Several high-quality predictive indices are available, but artificial intelligence algorithms offer the potential for higher predictive capability.

OBJECTIVE: This study aimed to construct and validate an artificial intelligence prediction model for diabetes remission after Roux-en-Y gastric bypass surgery.

METHODS: Patients who underwent surgery from 2007 to 2017 were included in the study, with collection of individual data from the Scandinavian Obesity Surgery Registry (SOReg), the Swedish National Patients Register, the Swedish Prescribed Drugs Register, and Statistics Sweden. A 7-layer convolution neural network (CNN) model was developed using 80% (6446/8057) of patients randomly selected from SOReg and 20% (1611/8057) of patients for external testing. The predictive capability of the CNN model and currently used scores (DiaRem, Ad-DiaRem, DiaBetter, and individualized metabolic surgery) were compared.

RESULTS: In total, 8057 patients with T2D were included in the study. At 2 years after surgery, 77.09% achieved pharmacological remission (n=6211), while 63.07% (4004/6348) achieved complete remission. The CNN model showed high accuracy for cessation of antidiabetic drugs and complete remission of T2D after gastric bypass surgery. The area under the receiver operating characteristic curve (AUC) for the CNN model for pharmacological remission was 0.85 (95% CI 0.83-0.86) during validation and 0.83 for the final test, which was 9%-12% better than the traditional predictive indices. The AUC for complete remission was 0.83 (95% CI 0.81-0.85) during validation and 0.82 for the final test, which was 9%-11% better than the traditional predictive indices.

CONCLUSIONS: The CNN method had better predictive capability compared to traditional indices for diabetes remission. However, further validation is needed in other countries to evaluate its external generalizability.

Severe obesity has been associated with numerous comorbidities and reduced health-related quality of life (HRQoL). Although many studies have reported changes in HRQoL after bariatric surgery, few were long-term prospective studies. We examined the performance of the convolution neural network (CNN) for predicting 5-year HRQoL after bariatric surgery based on the available preoperative information from the Scandinavian Obesity Surgery Registry (SOReg). CNN was used to predict the 5-year HRQoL after bariatric surgery in a training dataset and evaluated in a test dataset. In general, performance of the CNN model (measured as mean squared error, MSE) increased with more convolution layer filters, computation units, and epochs, and decreased with a larger batch size. The CNN model showed an overwhelming advantage in predicting all the HRQoL measures. The MSEs of the CNN model for training data were 8% to 80% smaller than those of the linear regression model. When the models were evaluated using the test data, the CNN model performed better than the linear regression model. However, the issue of overfitting was apparent in the CNN model. We concluded that the performance of the CNN is better than the traditional multivariate linear regression model in predicting long-term HRQoL after bariatric surgery; however, the overfitting issue needs to be mitigated using more features or more patients to train the model.

Previously published literature has identified a few predictors of health-related quality of life (HRQoL) after bariatric surgery. However, performance of the predictive models was not evaluated rigorously using real world data. To find better methods for predicting prognosis in patients after bariatric surgery, we examined performance of the Bayesian networks (BN) method in predicting long-term postoperative HRQoL and compared it with the convolution neural network (CNN) and multivariable logistic regression (MLR). The patients registered in the Scandinavian Obesity Surgery Registry (SOReg) were used for the current study. In total, 6542 patients registered in the SOReg between 2008 and 2012 with complete demographic and preoperative comorbidity information, and preoperative and postoperative 5-year HROoL scores and comorbidities were included in the study. HRQoL was measured using the RAND-SF-36 and the obesity-related problems scale. Thirty-five variables were used for analyses, including 19 predictors and 16 outcome variables. The Gaussian BN (GBN), CNN, and a traditional linear regression model were used for predicting 5-year HRQoL scores, and multinomial discrete BN (DBN) and MLR were used for 5-year comorbidities. Eighty percent of the patients were randomly selected as a training dataset and 20% as a validation dataset. The GBN presented a better performance than the CNN and the linear regression model; it had smaller mean squared errors (MSEs) than those from the CNN and the linear regression model. The MSE of the summary physical scale was only 0.0196 for GBN compared to the 0.0333 seen in the CNN. The DBN showed excellent predictive ability for 5-year type 2 diabetes and dyslipidemia (area under curve (AUC) = 0.942 and 0.917, respectively), good ability for 5-year hypertension and sleep apnea syndrome (AUC = 0.891 and 0.834, respectively), and fair ability for 5-year depression (AUC = 0.750). Bayesian networks provide useful tools for predicting long-term HRQoL and comorbidities in patients after bariatric surgery. The hybrid network that may involve variables from different probability distribution families deserves investigation in the future.

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.

Quality of life is a key outcome that is not rigorously measured in obesity treatment research due to the lack of standardization of patient-reported outcomes (PROs) and PRO measures (PROMs). The S.Q.O.T. initiative was founded to Standardize Quality of life measurement in Obesity Treatment. A first face-to-face, international, multidisciplinary consensus meeting was conducted to identify the key PROs and preferred PROMs for obesity treatment research. It comprised of 35 people living with obesity (PLWO) and healthcare providers (HCPs). Formal presentations, nominal group techniques, and modified Delphi exercises were used to develop consensus-based recommendations. The following eight PROs were considered important: self-esteem, physical health/functioning, mental/psychological health, social health, eating, stigma, body image, and excess skin. Self-esteem was considered the most important PRO, particularly for PLWO, while physical health was perceived to be the most important among HCPs. For each PRO, one or more PROMs were selected, except for stigma. This consensus meeting was a first step toward standardizing PROs (what to measure) and PROMs (how to measure) in obesity treatment research. It provides an overview of the key PROs and a first selection of the PROMs that can be used to evaluate these PROs.

The lack of standardization in patient-reported outcome measures (PROMs) has made measurement and comparison of quality of life (QoL) outcomes in research focused on obesity treatment challenging. This study reports on the results of the second and third global multidisciplinary Standardizing Quality of life measures in Obesity Treatment (S.Q.O.T.) consensus meetings, where a core set of PROMs to measure nine previously selected patient-reported outcomes (PROs) in obesity treatment research was established. The S.Q.O.T. II online and S.Q.O.T. III face-to-face hybrid consensus meetings were held in October 2021 and May 2022. The meetings were led by an independent moderator specializing in PRO measurement. Nominal group techniques, Delphi exercises, and anonymous voting were used to select the most suitable PROMs by consensus. The meetings were attended by 28 and 27 participants, respectively, including a geographically diverse selection of people living with obesity (PLWO) and experts from various disciplines. Out of 24 PROs and 16 PROMs identified in the first S.Q.O.T. consensus meeting, the following nine PROs and three PROMs were selected via consensus: BODY-Q (physical function, physical symptoms, psychological function, social function, eating behavior, and body image), IWQOL-Lite (self-esteem), and QOLOS (excess skin). No PROM was selected to measure stigma as existing PROMs deemed to be inadequate. A core set of PROMs to measure QoL in research focused on obesity treatment has been selected incorporating patients' and experts' opinions. This core set should serve as a minimum to use in obesity research studies and can be combined with clinical parameters.

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.

PURPOSE: Case reports suggest that patients with previous gastric bypass have an increased risk of severe hypocalcemia after total thyroidectomy, but there are no population-based studies. The prevalence of gastric bypass before thyroidectomy and the risk of hypocalcemia after thyroidectomy in patients with previous gastric bypass were investigated.

METHODS: By cross-linking The Scandinavian Quality Registry for Thyroid, Parathyroid and Adrenal Surgery with the Scandinavian Obesity Surgery Registry patients operated with total thyroidectomy without concurrent or previous surgery for hyperparathyroidism were identified and grouped according to previous gastric bypass. The risk of treatment with intravenous calcium during hospital stay, and with oral calcium and vitamin D at 6 weeks and 6 months postoperatively was calculated by using multiple logistic regression in the overall cohort and in a 1:1 nested case-control analysis.

RESULTS: We identified 6115 patients treated with total thyroidectomy. Out of these, 25 (0.4 %) had undergone previous gastric bypass surgery. In logistic regression, previous gastric bypass was not associated with treatment with i.v. calcium (OR 2.05, 95 % CI 0.48-8.74), or calcium and/or vitamin D at 6 weeks (1.14 (0.39-3.35), 1.31 (0.39-4.42)) or 6 months after total thyroidectomy (1.71 (0.40-7.32), 2.28 (0.53-9.75)). In the nested case-control analysis, rates of treatment for hypocalcemia were similar in patients with and without previous gastric bypass.

CONCLUSION: Previous gastric bypass surgery was infrequent in patients undergoing total thyroidectomy and was not associated with an increased risk of postoperative hypocalcemia.

Purpose: Diverging results have been reported with regards to the occurrence and progression of diabetic retinopathy following gastric bypass surgery (GBP) in patients with diabetes. We aimed to investigate the incidence of diabetic ocular complications in a nationwide study in Sweden in obese patients with type 2 diabetes mellitus (T2DM) following GBP and compared to a matched cohort of patients with T2DM not subjected to GBP surgery.

Setting: Nationwide registry study in Sweden.

Methods: We used data from two nationwide registers in Sweden: the Scandinavian Obesity Surgery Registry (SOReg) and the National Diabetes Registry (NDR). Patients with T2DM who had undergone GBP 2007-2013 reported to the SOReg were matched (1:1) with patients with T2DM from the NDR who had not had GBP surgery for obesity, based on sex, age, body mass index (BMI) and calender time (year). Follow-up data were obtained until December 31, 2015. The main outcome was occurrence of new diabetic retinopathy and was assessed with Cox proportional-hazards regression model. The importance of potential risk factors was assessed using a machine learning approach.

Results: The study population consisted of 5321 patients who had undergone GBP and 5321 matched controls in NDR, and was followed up for a mean of 4.5 years. Mean age was 49.0 (SD 9.5) in the GBP and 47.1 (11.5) years in the control patients, respectively. BMI and HbA1c at baseline were 42.0 (5.7) and 60.0 (16.8) in the GBP group and 40.9 (7.3) kg/m2 and 58.5 (16.9) mmol/mol in the control group. Duration of diabetes was approximately 6 years in both groups. The risk for new diabetic retinopathy was reduced in the GBP patients (hazard ratio [HR] 0·62, 95% CI 0·49–0·78; p<0.001). The most important risk factors for development of diabetic retinopathy were diabetes duration, HbA1c, glomerular filtration rate (GFR), use of insulin and BMI. There was no evidence of increased risk for development of sight-threatening or treatment-requiring diabetic ocular complications such as diabetic macular edema, proliferative diabetic retinopathy, need for intravitreal drug administration, panretinal photocoagulation or vitrectomy.

Conclusions: In this nationwide large cohort study of patients with type 2 diabetes we found a beneficial effect of GBP surgery on the risk for development of diabetic retinopathy. Furthermore, there were no indications for increased occurrence of sight-threatening or treatment-requiring diabetic retinopathy. These data provide support that, besides standard screening for diabetic retinopathy, there is no need for extended ophthalmological surveillance of patients with type 2 diabetes undergoing GBP surgery.

BACKGROUND: Laparoscopic gastric bypass (LGBP) is a well-documented surgical intervention for severe obesity. Recently, laparoscopic sleeve gastrectomy (LSG) has gained increased popularity. Short-term follow-up in limited-sized randomized trials comparing LGBP and LSG show no major differences in weight-loss, adverse events, or effect on comorbidities; however, there is a lack of sufficiently powered, pragmatic, randomized controlled trials comparing the mid- and long-term results of the two methods.

METHOD: BEST is a randomized, registry-based, multicenter trial comparing LGBP and LSG. The trial has two primary outcomes; rates of substantial complications (SC) and total body weight loss. We hypothesize that patients treated with LSG will experience 35% fewer substantial complications during the 5-year follow-up compared to patients treated with LGBP, and that the efficacy of LSG will remain within a non-inferiority margin of 5% in terms of weight loss. Our sample size calculation, using data from the Scandinavian Obesity Surgery Registry (SOReg), shows a power of 80% for SC and > 95% for weight loss at p < .025 with a total of 2100 included patients. The design of the trial will also enable comparisons within several relevant patient subgroups.

CONCLUSIONS: As a large-sized, pragmatic, randomized trial, BEST will provide robust data comparing LGBP with LSG by generating long-term results on weight loss and SC's, as well as secondary outcomes and comparisons within patient subgroups. The use of a well-established registry for registration of all data facilitates a large multicenter trial, and combines the strengths of registry studies with those of a randomized trial.

Clinical Trials registry: NCT02767505.

Background and aims: To study the effects of obesity treatment with gastric bypass surgery on hospitalization for heart failure (HF) and atrial fibrillation (AF) in patients with type 2 diabetes (T2D) and obesity. We also studied the effects of gastric bypass surgery on mortality in a subgroup of individuals with preexisting heart failure.

Materials and methods: In this register-based nationwide cohort study we compared individuals with T2D and obesity that underwent Roux-en-Y gastric bypass surgery (RYGB) with matched individuals with T2D and obesity that did not undergo surgery. Data was gathered by linking the Swedish National Diabetes Register and Scandinavian Obesity Surgery Registry. Matching of individuals for age, gender, BMI and calendar time was done using a time updated propensity score. The main outcome measures were hospitalization for HF and/or AF, and mortality in patients with preexisting HF. The risk for heart failure, AF and death were assessed using a Cox-proportional hazards regression model that addressed measured confounding.

Results: We identified 5321 individuals with T2D and obesity that had undergone RYGB between January 2007 and December 2013 and 5321 matched controls. The individuals includedwere between 18 and 65 years old and had a BMI > 27.5 kg/m2. The follow-up time for hospitalization was until the end of 2015 (mean 4.5 years) and the end of 2016 for death. Our results show a 73% lower risk for HF (HR 0.27 (0.19, 0.38) p<0.001), 41% for AF (HF 0.59 (0.44, 0.78) p < 0.001), and 77% for concomitant AF and HF (HR0.23 (0.12, 0.46) p < 0.001) in the surgically treated group. In patients with preexisting HF we observed significantly lower mortality in the group that underwent surgery (HR0.23 (0.12, 0.43) p < 0.001).

Conclusion: Bariatric surgery may reduce risk for HF and AF in patients with T2D and obesity, speculatively via positive cardiovascular and renal effects. Obesity treatment with surgery may also be a valuable alternative in selected patients with T2D and HF.

OBJECTIVE: To study the potential long-term benefits and possible complications of bariatric surgery in patients with type 1 diabetes (T1D).

RESEARCH DESIGN AND METHODS: In this register-based nationwide cohort study, we compared individuals with T1D and obesity who underwent Roux-en-Y gastric bypass (RYGB) surgery with patients with T1D and obesity matched for age, sex, BMI, and calendar time that did not undergo surgery. By linking the Swedish National Diabetes Register and Scandinavian Obesity Surgery Registry study individuals were included between 2007 and 2013. Outcomes examined included all-cause mortality, cardiovascular disease, stroke, heart failure, and hospitalization for serious hypo- or hyperglycemic events, amputation, psychiatric disorders, changes in kidney function, and substance abuse.

RESULTS: We identified 387 individuals who had undergone RYGB and 387 control patients. Follow-up for hospitalization was up to 9 years. Analysis showed lower risk for cardiovascular disease (hazard ratio [HR] 0.43; 95% CI 0.20-0.9), cardiovascular death (HR 0.15; 95% CI 0.03-0.68), hospitalization for heart failure (HR 0.32; 95% CI 0.15-0.67) and stroke (HR 0.18; 95% CI 0.04-0.82) for the RYGB group. There was a higher risk for serious hyperglycemic events (HR 1.99; 95% CI 1.07-3.72) and substance abuse (HR 3.71; 95% CI 1.03-3.29) after surgery.

CONCLUSIONS: This observational study suggests bariatric surgery may yield similar benefits on risk for cardiovascular outcomes and mortality in patients with T1D and obesity as for patients with type 2 diabetes. However, some potential serious adverse effects suggest need for careful monitoring of such patients after surgery.

Background: Obesity and diabetes mellitus are strongly associated with heart failure (HF) and atrial fibrillation (AF). The benefits of bariatric surgery on cardiovascular outcomes are known in people with or without diabetes mellitus. Surgical treatment of obesity might also reduce the incidence of HF and AF in individuals with obesity and type 2 diabetes mellitus (T2DM).

Methods and Results: In this register-based nationwide cohort study we compared individuals with T2DM and obesity who underwent Roux-en-Y gastric bypass surgery with matched individuals not treated with surgery. The main outcome measures were hospitalization for HF and/or AF and mortality in patients with preexisting HF. We identified 5321 individuals with T2DM and obesity who had undergone Roux-en-Y gastric bypass surgery between January 2007 and December 2013 and 5321 matched controls. The individuals included were 18 to 65 years old and had a body mass index >27.5 kg/m2. The follow-up time for hospitalization was until the end of 2015 (mean 4.5 years) and the end of 2016 for death. Our results show a 73% lower risk for HF (hazard ratio [HR], 0.27; CI, 0.19-0.38), 41% for AF (HR, 0.59; CI, 0.44-0.78), and 77% for concomitant AF and HF (HR, 0.23; CI, 0.12-0.46) in the surgically treated group. In patients with preexisting HF we observed significantly lower mortality in the group who underwent surgery (HR, 0.23; 95% CI, 0.12-0.43).

Conclusion:s Bariatric surgery may reduce risk for HF and AF in patients with T2DM and obesity, speculatively via positive cardiovascular and renal effects. Obesity treatment with surgery may also be a valuable alternative in selected patients with T2DM and HF. 

Background and purpose: Obesity is a considerable medical challenge in society. We investigated the risk of revision for any reasons and for infection in patients having total knee arthroplasty (TKA) for osteoarthritis (OA) within 2 years after bariatric surgery (BS) and compared them with TKAs without BS.

Patients and methods: We used the Scandinavian Obesity Surgery Registry (SOReg) and the Swedish Knee Arthroplasty Register (SKAR) to identify patients operated on in 2009-2019 with BS who had had primary TKA for OA within 2 years after the BS (BS group) and compared them with TKAs without prior BS (noBS group). We determined adjusted hazard ratio (HR) for the BS group and noBS group using Cox proportional hazard regression for revision due to any reasons and for infection. Adjustments were made for sex, age groups, and BMI categories preoperatively.

Results: 441 patients were included in the BS group. The risk of revision for infection was higher for the BS group with HR 2.2 (95% CI 1.1-4.7) adjusting for BMI before the TKA, while the risk of revision for any reasons was not statistically significant different for the BS group with HR 1.3 (CI 0.9-2.1). Corresponding figures when adjusting for BMI before the BS were HR 0.9 (CI 0.4-2) and HR 1.2 (CI 0.7-2).

Interpretation: Our findings did not indicate that BS prior to TKA was associated with lower risk of revision.

BACKGROUND: The impact of obesity on patient-reported outcome (PRO) after total knee arthroplasty (TKA) surgery has demonstrated varying results. We evaluated knee pain, Activity in Daily Life function (ADL), and satisfaction after TKA surgery in patients with and without prior bariatric surgery (BS).

METHODS: Scandinavian Obesity Surgery Registry (SOReg) and the Swedish Knee Arthroplasty Register (SKAR) were used to identify patients operated on with primary TKA for osteoarthritis (OA) between 2009 and 2019 that had a BS within 2 years before the TKA (BS group). These patients were compared to patients with TKA without prior BS (no BS group). The patients filled in the Knee injury and Osteoarthritis Outcome Score (KOOS) preoperatively and one year postoperatively as well as satisfaction with the surgery one year postoperatively. Multiple linear regression analysis was used to evaluate 1-year postoperative KOOS pain and ADL function between the 2 groups. Adjustments were made for sex, age, and preoperative KOOS pain and ADL function respectively.

RESULTS: Forty-four patients were included in the BS group and 3,525 patients in the no BS group. We found no statistically or clinically significant difference in one-year postoperative KOOS pain and ADL function between the BS group and the no BS group. The majority of the patients in both groups were classified as satisfied or very satisfied one year postoperatively to the TKA.

CONCLUSIONS: Our results indicate that patients without BS prior to the TKA gain similar 1-year outcome in pain, ADL function and satisfaction as patients with prior BS.

BACKGROUND: Patients with obesity have a higher risk of complications after total knee arthroplasty (TKA). We investigated the change in weight 1 and 2 years post-Bariatric Surgery (BS) in patients that had undergone both TKA and BS as well as the risk of revision after TKA based on if BS was performed before or after the TKA.

METHODS: Patients who had undergone BS within 2 years before or after TKA were identified from the Scandinavian Obesity Surgery Register (SOReg) and the Swedish Knee Arthroplasty Register (SKAR) between 2007 and 2019 and 2009 and 2020, respectively. The cohort was divided into two groups; patients who underwent TKA before BS (TKA-BS) and patients who underwent BS before TKA (BS-TKA). Multilinear regression analysis and a Cox proportional hazards model were used to analyze weight change after BS and the risk of revision after TKA.

RESULTS: Of the 584 patients included in the study, 119 patients underwent TKA before BS and 465 underwent BS before TKA. No association was detected between the sequence of surgery and total weight loss 1 and 2 years post-BS, - 0.1 (95% confidence interval (CI), - 1.7 to 1.5) and - 1.2 (95% CI, - 5.2 to 2.9), or the risk of revision after TKA [hazard ratio 1.54 (95% CI 0.5-4.5)].

CONCLUSION: The sequence of surgery in patients undergoing both BS and TKA does not appear to be associated with weight loss after BS or the risk of revision after TKA.

BACKGROUND: Although bariatric surgery is an effective treatment for type 2 diabetes (T2D) in patients with morbid obesity, further studies are needed to evaluate factors influencing the chance of achieving diabetes remission. The objective of the present study was to investigate the association between T2D duration and the chance of achieving remission of T2D after bariatric surgery.

METHODS AND FINDINGS: We conducted a nationwide register-based cohort study including all adult patients with T2D and BMI ≥ 35 kg/m2 who received primary bariatric surgery in Sweden between 2007 and 2015 identified through the Scandinavian Obesity Surgery Registry. The main outcome was remission of T2D, defined as being free from diabetes medication or as complete remission (HbA1c < 42 mmol/mol without medication). In all, 8,546 patients with T2D were included. Mean age was 47.8 ± 10.1 years, mean BMI was 42.2 ± 5.8 kg/m2, 5,277 (61.7%) were women, and mean HbA1c was 58.9 ± 17.4 mmol/mol. The proportion of patients free from diabetes medication 2 years after surgery was 76.6% (n = 6,499), and 69.9% at 5 years (n = 3,765). The chance of being free from T2D medication was less in patients with longer preoperative duration of diabetes both at 2 years (odds ratio [OR] 0.80/year, 95% CI 0.79-0.81, p < 0.001) and 5 years after surgery (OR 0.76/year, 95% CI 0.75-0.78, p < 0.001). Complete remission of T2D was achieved in 58.2% (n = 2,090) at 2 years, and 46.6% at 5 years (n = 681). The chance of achieving complete remission correlated negatively with the duration of diabetes (adjusted OR 0.87/year, 95% CI 0.85-0.89, p < 0.001), insulin treatment (adjusted OR 0.25, 95% CI 0.20-0.31, p < 0.001), age (adjusted OR 0.94/year, 95% CI 0.93-0.95, p < 0.001), and HbA1c at baseline (adjusted OR 0.98/mmol/mol, 95% CI 0.97-0.98, p < 0.001), but was greater among males (adjusted OR 1.57, 95% CI 1.29-1.90, p < 0.001) and patients with higher BMI at baseline (adjusted OR 1.07/kg/m2, 95% CI 1.05-1.09, p < 0.001). The main limitations of the study lie in its retrospective nature and the low availability of HbA1c values at long-term follow-up.

CONCLUSIONS: In this study, we found that remission of T2D after bariatric surgery was inversely associated with duration of diabetes and was highest among patients with recent onset and those without insulin treatment.

BACKGROUND: Symptomatic postbariatric hypoglycemia (PBH) is a known complication that can occur a few years after Roux-en-Y gastric bypass (RYGB). There is currently no established rating scale for PBH-associated symptoms developed for use in Swedish populations. The aim of the study was to translate an already existing questionnaire into Swedish and to test its reliability.

METHODS: The study included forward and backward translations of the original Dumping Severity Scale (DSS) questionnaire with 8 items regarding symptoms of early dumping and 6 items regarding hypoglycemia, with each item graded on a 4-point Likert scale. The reliability of the Swedish translated questionnaire (DSS-Swe) was estimated using internal consistency and test-retest methods.

RESULTS: A total of 200 patients were included in the study. Good internal consistency was demonstrated regarding the items related to early dumping symptoms, with a Cronbach's alpha coefficient of 0.82, and very good agreement in terms of test-retest reliability, with an overall intraclass correlation coefficient (ICC) of 0.91 (95% CI 0.88-0.93). The items related to hypoglycemia yielded a good Cronbach's alpha coefficient of 0.76 and an ICC of 0.89 (95% CI 0.85-0.91).

CONCLUSION: The DSS-Swe questionnaire shows good reliability regarding both internal consistency and test-retest performance for use in Swedish populations.

Dumping and post-bariatric hypoglycaemia (PBH) are side effects that occur after bariatric surgery. The aim of this study was to estimate the prevalence of dumping and PBH symptoms before Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG) at 6 months, 1 year, 2 years and 5 years after surgery in a Swedish population. A cross-sectional single-centre study was performed at Lindesberg Hospital, Region Örebro County, Sweden, between 2020 and 2023. The Swedish version of the Dumping Severity Scale (DSS-Swe) questionnaire, which includes eight items regarding dumping symptoms and six items regarding hypoglycaemia symptoms, was used. A total of 742 DSS-Swe questionnaires were included. The average age at surgery was 42.0 years (standard deviation [SD] = 11.9), and the average body mass index was 41.8 kg/m2 (SD = 5.9). The surgical methods consisted of RYGB (66.3%) and SG (33.7%). The proportion of RYGB patients with highly suspected dumping increased from 4.9% before surgery to 26.3% (adjusted odds ratio [OR] = 7.35, 95% confidence interval [CI] = 3.08-17.52) at the 5-year follow-up. PBH symptoms increased from 1.4% before surgery to 19.3% at the 5-year follow-up (adjusted OR = 17.88, 95% CI = 4.07-78.54). For SG patients, no significant increase in dumping or PBH symptoms was observed. In patients with persistent type 2 diabetes (T2D), there were no cases of highly suspected hypoglycaemia following RYGB or SG. Symptoms of dumping and PBH were common after RYGB, while no clear increase was observed after SG. Persistent T2D seems to be a protective factor against PBH symptoms.

BACKGROUND: Although a large proportion of patients with type 2 diabetes (T2DM) who have undergone metabolic surgery experience initial remission some patients later suffer from relapse. While several factors associated with T2D remission are known, less is known about factors that may influence relapse.

OBJECTIVES: To identify possible risk factors for T2D relapse in patients who initially experienced remission.

SETTING: Nationwide, registry-based study.

METHODS: We conducted a nationwide registry-based retrospective cohort study including all adult patients with T2D and body mass index ≥35 kg/m² who received primary metabolic surgery with Roux-en-Y gastric bypass (RYGB) or sleeve gastrectomy (SG) in Sweden between 2007 and 2015. Patients who achieved complete diabetes remission 2 years after surgery was identified and analyzed. Main outcome measure was postoperative relapse of T2D, defined as reintroduction of diabetes medication.

RESULTS: In total, 2090 patients in complete remission at 2 years after surgery were followed for a median of 5.9 years (interquartile range [IQR] 4.3-7.2 years) after surgery. The cumulative T2D relapse rate was 20.1%. Duration of diabetes (hazard ratio [HR], 1.09; 95% confidence interval [CI], 1.05-1.14; P < .001), preoperative glycosylated hemoglobin A1C (HbA1C) level (HR, 1.01; 95% CI, 1.00-1.02; P = .013), and preoperative insulin treatment (HR, 2.67; 95% CI, 1.84-3.90; P < .001) were associated with higher rates for relapse, while postoperative weight loss (HR, .93; 95% CI, .91-.96; P < .001), and male sex (HR, .65; 95% CI, .46-.91; P = .012) were associated with lower rates.

CONCLUSION: Longer duration of T2D, higher preoperative HbA1C level, less postoperative weight loss, female sex, and insulin treatment prior to surgery are risk factors for T2D relapse after initial remission.

OBJECTIVE: To investigate whether gastric bypass before pregnancy is associated with reduced risk of preeclampsia.

DESIGN: Nationwide matched cohort study.

SETTING: Swedish national health care.

POPULATION: =2766:2766) on pre-surgery/early-pregnancy BMI, diabetes status (pre-surgery/pre-conception), maternal age, early-pregnancy smoking status, educational level, height, country of birth, delivery year and history of preeclampsia.

MAIN OUTCOME MEASURES: Preeclampsia categorised into any, preterm onset (<37+0 weeks), and term onset (≥37+0 weeks).

RESULTS: (39kg). Post-gastric bypass pregnancies had lower risk of preeclampsia compared to pre-surgery BMI-matched controls (1.7 vs. 9.7 per 100 pregnancies; hazard ratio [HR] 0.21, 95%CI 0.15-0.28) and early-pregnancy BMI-matched controls (1.9 vs. 5.0 per 100 pregnancies; HR 0.44, 95%CI 0.33-0.60). Although relative risks for preeclampsia for post-gastric bypass pregnancies vs. pre-surgery matched controls was similar, absolute risk differences were significantly greater for nulliparous (RD -13.6 per 100 pregnancies, 95%CI -16.1 to -11.2) vs. parous women (RD -4.4 per 100 pregnancies, 95%CI -5.7 to -3.1).

CONCLUSION: We found that gastric bypass was associated with lower risk of preeclampsia, with the largest absolute risk reduction among nulliparous women.

BACKGROUND: It remains unknown whether routine division of the greater omentum during laparoscopic Roux-en-Y gastric bypass (LRYGB) influences the risk for small bowel obstruction (SBO) after RYGB.

OBJECTIVE: To evaluate the effect of omental division on SBO after LRYGB stratified by handling of the mesenteric defects.

SETTING: Nationwide, registry-based.

METHODS: In this registry-based cohort study, 40,517 patients who underwent LRYGB in Sweden within the period from January 1, 2007, to December 31, 2019, with data from the Scandinavian Obesity Surgery Registry (SOReg) were included. The study was based on combined data from the SOReg, the National Patient Register, the Swedish Prescribed Drugs Register, and the Total Population Registry. The main outcome was reoperation for SBO.

RESULTS: During a follow-up period of 5.9 ± 2.6 years, the cumulative incidence of SBO was 11.2% in the nondivision group compared with 9.7% among patients with divided omentum (hazard ratio [HR] = .83, 95% confidence interval [CI]: .77-.89, P < .001). The association was seen in patients without mesenteric defects closure (HR = .69, 95% CI: .61-.78, P < .001) as well as patients with closed mesenteric defects (HR = .80, 95% CI: .74-.87, P < .001).

CONCLUSION: Division of the greater omentum is associated with reduced risk for SBO after antecolic, antegastric LRYGB and should be considered as a complement to mesenteric defects closure to further reduce the risk for SBO after LRYGB.

BACKGROUND: More than 10% of the global population has a BMI above 35. Bariatric surgery is an efficient way to treat this condition. Unfortunately, there is a risk of nutritional deficiencies. The number of studies after a longer time span is scarce. The aim of this study was to determine the occurrence of anaemia five and ten years after bariatric surgery and how it was related to substitution therapy.

PATIENTS AND METHODS: Registry data from individuals having primary bariatric surgery in the Scandinavian Obesity Surgery Registry (SOReg) from 2007 to 2022 and with a follow-up at five or ten years was retrieved. Demographic data including weight, as well as method of surgery, Hb levels, supplementation, PPI use and stomal ulcerations were recorded.

RESULTS: In total, 39,992 individuals (mean age 41 years, range 18-74, 77% women) could be included. The majority, 78%, had undergone laparoscopic Roux-en-Y gastric bypass. After five years, 2838/13,944 women (20.3%) and 456/4049 men (11.2%) had anaemia. After ten years, 644/3400 women (18.9%) and 178/947 men (18.8%) had anaemia. The use of oral iron increased from 40 to 45%, and the need for parenteral iron intake increased from 5 to 11%.

CONCLUSIONS: Anaemia is a significant but manageable condition five and ten years after bariatric surgery. Despite the prescription of oral iron supplements to 45% ten years after surgery, the Hb levels could still not be fully restored. Consequently, the importance of follow-up visits and continuous supplementation is emphasised.

PURPOSE: Obesity is associated with increased incidence of kidney stones, a risk further increased by metabolic and bariatric surgery, particularly after procedures with a malabsorptive component. However, there is a paucity in reports on baseline risk factor and on larger population-based cohorts. The objective was to evaluate incidence and risk factors for kidney stones after bariatric surgery by comparing them to an age-, sex-, and geographically matched cohort from the normal population.

MATERIAL AND METHODS: Patients operated with primary Roux-en-Y gastric bypass (RYGB), sleeve gastrectomy (SG), or biliopancreatic diversion with duodenal switch (BPD-DS) from 2007 until 2017 within the Scandinavian Obesity Surgery registry were matched 1:10 to controls from the normal population. Hospital admission or outpatient visits due to kidney stones registered in the National Patient Registry were considered as endpoint.

RESULTS: The study included 58,366 surgical patients (mean age 41.0±11.1, BMI 42.0±5.68, 76% women) with median follow-up time 5.0 [IQR 2.9-7.0] years and 583,660 controls. All surgical procedures were associated with a significantly increased risk for kidney stones (RYGB, HR 6.16, [95% CI 5.37-7.06]; SG, HR 6.33, [95% CI 3.57-11.25]; BPD/DS, HR 10.16, [95% CI 2.94-35.09]). Higher age, type 2 diabetes hypertension at baseline, and a preoperative history of kidney stones were risk factors for having a postoperative diagnosis of kidney stones.

CONCLUSION: Primary RYGB, SG, and BPD/DS were all associated with a more than sixfold increased risk for postoperative kidney stones. The risk increased with advancing age, two common obesity-related conditions, and among patients with preoperative history of kidney stones.

The new Scandinavian Obesity Surgery Registry (SOReg) report may influence current guidelines. Patients without type 2 diabetes (T2DM) prior to bariatric surgery had lower mortality over 6.3 years compared to those with T2DM. Moreover, patients with T2DM who achieved remission within 1 year after surgery had lower mortality than those who did not remit. Finally, there was no threshold at 10 years, but rather a linear relationship between duration of T2DM and glycemic remission. The SOReg report challenges existing recommendations and clinical practice. A case may also be made for patients with T2DM who did not achieve glycemic remission after 1 year to have a combination approach of surgery with medicines rather than surgery alone. Ultimately, the impact of T2DM duration on glycemic remission again suggest that patients with T2DM should have bariatric surgery earlier.

Objectives: Long-term effects of gastric bypass (GBP) surgery have been presented in observational and randomised studies, but there are only limited data for persons with obesity and type 2 diabetes mellitus (T2DM) regarding postoperative complications.

Design: This is a nationwide observational study based on two quality registers in Sweden (National Diabetes Register, NDR and Scandinavian Obesity Surgery Register, SOReg) and other national databases.

Setting: After merging the data, we matched individuals with T2DM who had undergone GBP with those not surgically treated for obesity on propensity score, based on sex, age, body mass index (BMI) and calendar time. The risks of postoperative outcomes (rehospitalisations) were assessed using Cox regression models.

Participants: We identified 5321 patients with T2DM in the SOReg and 5321 matched controls in the NDR, aged 18-65 years, with BMI > 27.5 kg/m(2) and followed for up to 9 years.

Primary and secondary outcome measures: We assessed risks for all-cause mortality and hospitalisations for cardiovascular disease, severe kidney disease, along with surgical and other medical conditions.

Results: The results agree with the previously suggested lower risks of all-cause mortality (49%) and cardiovascular disease (34%), and we also found positive effects for severe kidney disease but significantly increased risks (twofold to ninefold) of several short-term complications after GBP, such as abdominal pain and gastrointestinal conditions, frequently requiring surgical procedures, apart from reconstructive plastic surgery. Long-term, the risk of anaemia was 92% higher, malnutrition developed approximately three times as often, psychiatric diagnoses were 33% more frequent and alcohol abuse was three times as great as in the control group.

Conclusions: This nationwide study confirms the benefits and describes the panorama of adverse events after bariatric surgery in persons with obesity and T2DM. Long-term postoperative monitoring and support, as better selection of patients by appropriate specialists in interdisciplinary settings, should be provided to optimise the outcomes.

OBJECTIVE: We examined detailed renal and cardiovascular (CV) outcomes after gastric bypass (GBP) surgery in people with obesity and type 2 diabetes mellitus (T2DM), across several renal function categories, in a nationwide cohort study.

RESEARCH DESIGN AND METHODS: We linked data from the National Diabetes Register and the Scandinavian Obesity Surgery Register with four national databases holding information on socioeconomic variables, medications, hospitalizations, and causes of death and matched 5,321 individuals with T2DM who had undergone GBP with 5,321 who had not (age 18-65 years, mean BMI >40 kg/m(2), mean follow-up >4.5 years). The risks of postoperative outcomes were assessed with Cox regression models.

RESULTS: During the first years postsurgery, there were small reductions in creatinine and albuminuria and stable estimated glomerular filtration rate (eGFR) in the GBP group. The incidence rates of most outcomes relating to renal function, CV disease, and mortality were lower after GBP, being particularly marked for heart failure (hazard ratio [HR] 0.33 [95% CI 0.24, 0.46]) and CV mortality (HR 0.36 [(95% CI 0.22, 0.58]). The risk of a composite of severe renal disease or halved eGFR was 0.56 (95% CI 0.44, 0.71), whereas nonfatal CV risk was lowered less (HR 0.82 [95% CI 0.70, 0.97]) after GBP. Risks for key outcomes were generally lower after GBP in all eGFR strata, including in individuals with eGFR

CONCLUSIONS: Our data suggest robust benefits for renal outcomes, heart failure, and CV mortality after GBP in individuals with obesity and T2DM. These results suggest that marked weight loss yields important benefits, particularly on the cardiorenal axis (including slowing progression to end-stage renal disease), whatever the baseline renal function status.

Background: The use of circular staplers with a low staple height is associated with a lower risk for complication when used to construct the gastroenterostomy in laparoscopic gastric bypass surgery. The influence of staple height on outcome when using linear staplers has not been studied.

Objectives: To investigate the influence of staple height when constructing the gastric pouch and gastroenterostomy using a linear stapler in laparoscopic gastric bypass surgery.

Setting: Nationwide, Sweden.

Methods: A retrospective, register-based cohort study, including all primary laparoscopic gastric bypass surgical procedures in Sweden registered in the Scandinavian Obesity Surgery Registry from January 2010 until January 2017, where linear staplers were used to construct the gastric pouch and the gastroenterostomy. Low stapler heights (closed height <= 1.0 mm) were compared with higher stapler heights (closed height >= 1.5 mm). The main outcome was postoperative complication within 30 days of surgery.

Results: Within the study period, 27,975 patients were identified from the Scandinavian Obesity Surgery Registry. A closed staple height >= 1.5 mm was associated with higher risk for postoperative complication within 30 days of surgery compared with lower staple height. The risk was greater when used to construct the gastric pouch (adjusted odd ratio 1.30, 95% confidence interval 1.17-1.44, P < .001) as well as when constructing the gastroenterostomy (adjusted odd ratio 1.32, 95% confidence interval 1.20-1.45, P < .001).

Conclusion: The use of low staple height for construction of the gastric pouch and gastroenterostomy in laparoscopic gastric bypass surgery was associated with lower complication rates. (C) 2019 American Society for Bariatric Surgery. Published by Elsevier Inc. All rights reserved.

Background and aims: Bariatric surgery (BS) is an effective treatment for long-term weight loss in people with type 2 diabetes (T2D) and obesity. However, long-term prospective data on the efficacy and safety of BS with roux-en-y gastric bypass or sleeve gastrectomy in T2D populations are limited. AIMS: Evaluate the long-term effects of BS in people with T2D up to 14 years after surgery.

Materials and methods: A nationwide, matched, longitudinal, retrospective study based on data from the Swedish National Diabetes Registry (NDR) and the Swedish Obesity Surgery Registry (SOReg). Both registries cover more than 95% of all individuals with T2D and bariatric surgeries, respectively. A cohort of 8399 individuals with T2D (SOReg) who had undergone BS between 2007 and 2020 was matched by sex, age and BMI, with a control group from NDR who had not had surgery (n=8399). This study assessed the 28-day mortality rate after a CVD event, the long-term incidence of heart and kidney failure, psychiatric disorders and nutritional deficiencies. Data on outcomes were collected as ICD codes from the Swedish National Patient Registry and the Cause of Death Registry. Risks were quantified using unadjusted Cox regression models, yielding HR with 95% CI.

Results: In total, 16798 individuals with overweight or obesity were included and followed for up to 14 years. The mean BMI at the start of follow-up was 41±6 kg/m 2 , with a mean age of 49±10 years for both groups. The mean duration of T2D at baseline was 6.1 years for the control group and 6.5 years for the surgery group. The surgical group had slightly higher HbA1 c levels and education, but were less often single and had lower nicotine use (standardised mean difference, SMD >0.1). No significant differences were observed in cholesterol, eGFR, the prevalence of CVD, heart and kidney failure, psychiatric disorders, or nutritional deficiencies at baseline (SMD<0.1). During follow-up, the risk of heart failure, kidney failure, and death within 28 days of a CVD event was up to 45% lower in the surgically treated group compared to the controls (p <0.0001). However, the risk of hospitalisation for psychiatric disorders was increased after surgery (HR 1.21; 95% CI 1.13-1.29; p<0.0001). The surgically treated individuals also had a twofold increased risk of developing nutritional deficiencies compared to controls (HR 2.06; CI 1.84-2.31; p<0.0001) during the follow-up period.

Conclusion: This nationwide study shows that the benefits of bariatric surgery on CVD death, and heart and kidney failure for people with T2D are maintained in the long term. However, surgery increases the risk of suffering from psychiatric disorders or nutritional deficiencies for these individuals.

Purpose: To study the occurrence and level of diabetic retinopathy (DRP) before and after planned bariatric surgery and to investigate potential risk factors for deterioration of DRP.

Methods: The Scandinavian Obesity Surgery Registry (SOReg) was used to identify diabetic patients who underwent gastric bypass (GBP) surgery at three centres in Sweden during 2008-2010. Information regarding DRP screening was obtained from ophthalmological patient charts. Patients who had DRP screening before and after GBP surgery were included in the study.

Results: The survey included 117 patients. Mean age was 50 (SD 10) years, body mass index (BMI) 43 (SD 8) kg/m(2) and HbA1c 64 (SD 18) mmol/mol before surgery. One year post-GBP, BMI was reduced to 31 (SD 6) kg/m(2). HbA1c was 43 (SD 10) mmol/mol, and in 66% (77/117) treatment for diabetes had been discontinued. Occurrence of DRP before GBP was as follows: no DRP 62%, mild 26%, moderate 10%, severe 0% and proliferative DRP 2%. No significant changes in occurrence of DRP after surgery were observed. Twelve patients (16%) developed mild DRP. In seven patients with pre-existing DRP, deterioration was observed and two of these patients required treatment for sight-threatening DRP. No association between preoperative BMI, HbA1c or reduction in HbA1c and worsening of DRP was found.

Conclusion: In a majority of patients, no deterioration of DRP following GBP was observed. Screening for DRP before planned surgery is recommended for all diabetic patients about to undergo bariatric surgery to identify any pre-existing DRP.

BACKGROUND: The personal economic impact of bariatric surgery is not well-described. OBJECTIVES: To examine earnings and work loss from 5 years before to 5 years after bariatric surgery compared with the general population.

SETTING: Nationwide matched cohort study in the Swedish health care system.

METHODS: Patients undergoing primary bariatric surgery (n = 15,828) and an equal number of comparators from the Swedish general population were identified and matched on age, sex, place of residence, and educational level. Annual taxable earnings (primary outcome) and annual work loss (secondary outcome combining months with sick leave and disability pension) were retrieved from Statistics Sweden. Participants were included in the analysis until the year of study end, emigration or death.

RESULTS: From 5 years before to 5 years after bariatric surgery, earnings increased for patients overall and in subgroups defined by education level and sex, while work loss remained relatively constant. Bariatric patients and matched comparators from the general population increased their earnings in a near parallel fashion, from 5 years before (mean difference -$3,489 [95%CI -3,918 to -3,060]) to 5 years after surgery (-$4,164 [-4,709 to -3,619]). Work loss was relatively stable within both groups but with large absolute differences both at 5 years before (1.09 months, [95%CI 1.01 to 1.17]) and 5 years after surgery (1.25 months, [1.11 to 1.40]).

CONCLUSIONS: Five years after treatment, bariatric surgery had not reduced the gap in earnings and work loss between surgery patients and matched comparators from the general population.

Background: The number of patients with myocardial infarction and severe obesity is increasing and there is a lack of evidence how these patients should be treated. The aim of this study was to investigate the association between metabolic surgery (Roux-en-Y gastric bypass and sleeve gastrectomy) and major adverse cardiovascular events in patients with previous myocardial infarction (MI) and severe obesity.

Methods: Of 566 patients with previous MI registered in the SWEDEHEART registry (Swedish Web-System for Enhancement and Development of Evidence-Based Care in Heart Disease Evaluated According to Recommended Therapies) undergoing metabolic surgery and registered in the nationwide Scandinavian Obesity Surgery Registry, 509 patients (Roux-en-Y gastric bypass n=465; sleeve gastrectomy n=44) could be matched 1:1 to a control with MI from SWEDEHEART, but no subsequent metabolic surgery regarding sex, age (+/- 3 years), year of MI (+/- 3 years), and body mass index (+/- 3). The 2 groups were well matched, except for a lower proportion of reduced ejection fraction after MI (7% versus 12%), previous heart failure (10% versus 19%), atrial fibrillation (6% versus 10%), and chronic obstructive pulmonary disease (4% versus 7%) in patients undergoing metabolic surgery.

Results: The median (interquartile range) follow-up time was 4.6 (2.7-7.1) years. The 8-year cumulative probability of major adverse cardiovascular events was lower in patients undergoing metabolic surgery (18.7% [95% CI, 15.9-21.5%] versus 36.2% [33.2-39.3%], adjusted hazard ratio, 0.44 [95% CI, 0.32-0.61]). Patients undergoing metabolic surgery had also a lower risk of death (adjusted HR, 0.45 [95% CI, 0.29-0.70]; MI, 0.24 [0.14-0.41]) and new onset heart failure, but there were no significant differences regarding stroke (0.91 [0.38-2.20]) and new onset atrial fibrillation (0.56 [0.31-1.01]).

Conclusions: In severely obese patients with previous MI, metabolic surgery is associated with a low risk for serious complications, lower risk of major adverse cardiovascular events, death, new MI, and new onset heart failure. These findings need to be confirmed in a randomized, controlled trial.

Objective: The aim of this study was to compare the use and short-term outcome of Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG) in Sweden, Norway, and the Netherlands.

Background: Although bariatric surgery is performed in high volumes worldwide, no consensus exists regarding the choice of bariatric procedure for specific groups of patients.

Methods: Data from 3 national registries for bariatric surgery were used. Patient selection, perioperative data (severe complications, mortality, and rate of readmissions within 30 days), and 1-year results (follow-up rate and weight loss) were studied.

Results: A total of 47,101 primary operations were registered, 33,029 (70.1%) RYGB and 14,072 (29.9%) SG. Patients receiving RYGB met international guidelines for having bariatric surgery more often than those receiving SG (91.9% vs 83,0%, P< 0.001). The 2 procedures did not differ in the rate of severe complications (2.6% vs 2.4%, P= 0.382), nor 30-day mortality (0.04% vs 0.03%, P= 0.821). Readmission rates were higher after RYGB (4.3% vs 3.4%, P< 0.001). One-year post surgery, less RYGB-patients were lost-to follow-up (12.1% vs 16.5%, P< 0.001) and RYGB resulted in a higher rate of patients with total weight loss of more than 20% (95.8% vs 84.6%, P< 0.001). While the weight-loss after RYGB was similar between hospitals, there was a great variation in weight loss after SG.

Conclusion: This study reflects the pragmatic use and short-term outcome of RYGB and SG in 3 countries in North-Western Europe. Both procedures were safe, with RYGB having higher weight loss and follow-up rates at the cost of a slightly higher 30-day readmission rate.

Introduction: The global prevalence of obesity has increased in recent decades, and bariatric surgery has become a part of the treatment algorithm of obesity. National high-quality registries enable large-scale evaluations of the use and outcome of bariatric surgery and may allow for improved knowledge. The main objective was to evaluate the rate and type of complications after primary bariatric surgery in three North-Western European countries using nationwide registries.

Materials and Methods: Data from three registries for bariatric surgery were used (January 2015-December 2016). All registries have nationwide coverage with data on patient characteristics, obesity-related diseases, surgical technique, complications, grading of complications, reinterventions, readmissions, and mortality. Eligibility criteria for bariatric surgery were similar and included body mass index of 40.0 or 35.0kg/m(2), with one or more obesity-associated diseases.

Results: A total of 35,858 procedures (32,177 primary) were registered. The most common procedure was gastric bypass in the Netherlands (78.9%) and Sweden (67.0%), and sleeve gastrectomy in Norway (58.2%). A total of 904 (2.8%) patients developed major complications after primary surgery and 12 patients (0.04%) died within 30days. Total number of complications between the registries were comparable (p=0.939). However, significant differences were seen for Clavien-Dindo Classification grades IIIb and IV (p<0.001). Pooled readmission rates were 4.3% (n=1386).

Discussion: Bariatric surgery is safely performed in the three evaluated countries. Standardization of registries and consensus of variables are essential for international comparison and may contribute to improved quality of treatment across nations.

Importance: There is a lack of studies evaluating sleeve gastrectomy compared with intensive lifestyle treatment in patients with class 1 obesity (body mass index [BMI] 30 to <35 [calculated as weight in kilograms divided by height in meters squared]).

Objective: To compare outcomes and safety of sleeve gastrectomy compared with intensive nonoperative obesity treatment in patients with class 1 obesity.

Design, Setting, and Participants: This matched, nationwide cohort study included patients with class 1 obesity who underwent a sleeve gastrectomy or intensive lifestyle treatment between January 1, 2012, and December 31, 2017, and who were registered in the Scandinavian Obesity Surgery Registry or the Itrim health database. Participants with class 1 obesity were matched 1:2 using a propensity score including age, sex, BMI, treatment year, education level, income, cardiovascular disease, and use of antibiotic drugs, antidepressants, and anxiolytics.

Interventions: Sleeve gastrectomy or intensive lifestyle treatment.

Main Outcomes and Measures: Outcomes included weight loss after intervention, changes in metabolic comorbidities, substance use disorders, self-harm, and major cardiovascular events retrieved from the National Patient Register, Prescribed Drug Register, and Cause of Death Register as well as the Scandinavian Obesity Surgery Registry and the Itrim health database. Data were analyzed from December 1, 2021 until May 31, 2022.

Results: The study included 1216 surgery patients and 2432 lifestyle participants with similar mean (SD) BMI (32.8 [1.4] vs 32.9 [1.4]), mean (SD) age (42.4 [9.7] vs 42.6 [12.7] years), and sex (1091 [89.7%] vs 2191 [90.1%] women). Surgery patients had greater 1-year weight loss compared with controls (22.9 kg vs 11.9 kg; mean difference, 10.7 kg; 95% CI, 10.0-11.5 kg; P < .001). Over a median follow-up of 5.1 years (IQR, 3.9-6.2 years), surgery patients had a lower risk of incident use of diabetes drugs (59.7 vs 100.4 events per 10 000 person-years; hazard ratio [HR], 0.60; 95% CI, 0.39-0.92; P = .02) and greater 2-year diabetes drug remission (48.4% vs 22.0%; risk difference 26.4%; 95% CI, 11.7%-41.0%; P < .001), but higher risk for substance use disorder (94 vs 50 events per 10 000 person-years; HR, 1.86; 95% CI, 1.30-2.67; P < .001) and self-harm (45 vs 25 events per 10 000 person-years; HR, 1.81; 95% CI, 1.09-3.01; P = .02). No between-group difference in occurrence of major cardiovascular events was observed (23.4 vs 24.8 events per 10 000 person-years; HR, 0.96; 95% CI, 0.49-1.91; P = .92).

Conclusions and Relevance: In this cohort study, compared with intensive nonoperative obesity treatment, sleeve gastrectomy in patients with class 1 obesity was associated with greater weight loss, diabetes prevention, and diabetes remission but a higher incidence of substance use disorder and self-harm.

AIM: To compare weight and glucometabolic outcomes of semaglutide and metabolic and bariatric surgery (MBS) for patients with type 2 diabetes and obesity.

MATERIALS AND METHODS: Patients treated with either semaglutide for a duration of ≥2 years or MBS in Sweden were identified within the Scandinavian Obesity Surgery Registry and the National Diabetes Registry and matched in a 1:1-2 ratio using a propensity score matching with a generalized linear model, including age, sex, glycated haemoglobin before treatment, duration of type 2 diabetes, use of insulin, presence of comorbidities and history of cancer, with good matching results but with a remaining imbalance for glomerular filtration rate and body mass index, which were then adjusted for in the following analyses. Main outcomes were weight loss and glycaemic control.

RESULTS: The study included 606 patients in the surgical group matched to 997 controls who started their treatment from 2018 until 2020. Both groups improved in weight and glucometabolic control. At 2 years after the intervention, mean glycated haemoglobin was 42.3 ± 11.18 after MBS compared with 50.7 ± 12.48 after semaglutide treatment (p < 0.001) with 382 patients (63.0%) and 139 (13.9%), respectively, reaching complete remission without other treatment than the intervention (p < 0.001). Mean total weight loss reached 26.4% ± 8.83% after MBS compared with 5.2% ± 7.87% after semaglutide (p < 0.001).

CONCLUSION: Semaglutide and MBS were both associated with improvements in weight and improved glycaemic control at 2 years after the start of the intervention, but MBS was associated with better weight loss and glucometabolic control.

BACKGROUND: Factors associated with risk for adverse outcome are important considerations in the preoperative assessment of patients for bariatric surgery. As yet, prediction models based on preoperative risk factors have not been able to predict adverse outcome sufficiently.

OBJECTIVE: This study aimed to identify preoperative risk factors and to construct a risk prediction model based on these.

METHODS: Patients who underwent a bariatric surgical procedure in Sweden between 2010 and 2014 were identified from the Scandinavian Obesity Surgery Registry (SOReg). Associations between preoperative potential risk factors and severe postoperative complications were analysed using a logistic regression model. A multivariate model for risk prediction was created and validated in the SOReg for patients who underwent bariatric surgery in Sweden, 2015.

RESULTS: Revision surgery (standardized OR 1.19, 95% confidence interval (CI) 1.14-0.24, p < 0.001), age (standardized OR 1.10, 95%CI 1.03-1.17, p = 0.007), low body mass index (standardized OR 0.89, 95%CI 0.82-0.98, p = 0.012), operation year (standardized OR 0.91, 95%CI 0.85-0.97, p = 0.003), waist circumference (standardized OR 1.09, 95%CI 1.00-1.19, p = 0.059), and dyspepsia/GERD (standardized OR 1.08, 95%CI 1.02-1.15, p = 0.007) were all associated with risk for severe postoperative complication and were included in the risk prediction model. Despite high specificity, the sensitivity of the model was low.

CONCLUSION: Revision surgery, high age, low BMI, large waist circumference, and dyspepsia/GERD were associated with an increased risk for severe postoperative complication. The prediction model based on these factors, however, had a sensitivity that was too low to predict risk in the individual patient case.