Weight recurrence after Sleeve Gastrectomy versus Roux-en-Y gastric bypass: a propensity score matched nationwide analysis.

BACKGROUND: Literature remains scarce on patients experiencing weight recurrence after initial adequate weight loss following primary bariatric surgery. Therefore, this study compared the extent of weight recurrence between patients who received a Sleeve Gastrectomy (SG) versus Roux-en-Y gastric bypass (RYGB) after adequate weight loss at 1-year follow-up. METHODS: All patients undergoing primary RYGB or SG between 2015 and 2018 were selected from the Dutch Audit for Treatment of Obesity. Inclusion criteria were achieving ≥ 20% total weight loss (TWL) at 1-year and having at least one subsequent follow-up visit. The primary outcome was ≥ 10% weight recurrence (WR) at the last recorded follow-up between 2 and 5 years, after ≥ 20% TWL at 1-year follow-up. Secondary outcomes included remission of comorbidities at last recorded follow-up. A propensity score matched logistic regression analysis was used to estimate the difference between RYGB and SG. RESULTS: A total of 19.762 patients were included, 14.982 RYGB and 4.780 SG patients. After matching 4.693 patients from each group, patients undergoing SG had a higher likelihood on WR up to 5-year follow-up compared with RYGB [OR 2.07, 95% CI (1.89-2.27), p < 0.01] and less often remission of type 2 diabetes [OR 0.69, 95% CI (0.56-0.86), p < 0.01], hypertension (HTN) [OR 0.75, 95% CI (0.65-0.87), p < 0.01], dyslipidemia [OR 0.44, 95% CI (0.36-0.54), p < 0.01], gastroesophageal reflux [OR 0.25 95% CI (0.18-0.34), p < 0.01], and obstructive sleep apnea syndrome (OSAS) [OR 0.66, 95% CI (0.54-0.8), p < 0.01]. In subgroup analyses, patients who experienced WR after SG but maintained ≥ 20%TWL from starting weight, more often achieved HTN (44.7% vs 29.4%), dyslipidemia (38.3% vs 19.3%), and OSAS (54% vs 20.3%) remission compared with patients not maintaining ≥ 20%TWL. No such differences in comorbidity remission were found within RYGB patients. CONCLUSION: Patients undergoing SG are more likely to experience weight recurrence, and less likely to achieve comorbidity remission than patients undergoing RYGB.

Predicting serious complication risks after bariatric surgery: external validation of the Michigan Bariatric Surgery Collaborative risk prediction model using the Dutch Audit for Treatment of Obesity.

BACKGROUND: Risk-prediction tools can support doctor-patient (shared) decision making in clinical practice by providing information on complication risks for different types of bariatric surgery. However, external validation is imperative to ensure the generalizability of predictions in a new patient population. OBJECTIVE: To perform an external validation of the risk-prediction model for serious complications from the Michigan Bariatric Surgery Collaborative (MBSC) for Dutch bariatric patients using the nationwide Dutch Audit for Treatment of Obesity (DATO). SETTING: Population-based study, including all 18 hospitals performing bariatric surgery in the Netherlands. METHODS: All patients registered in the DATO undergoing bariatric surgery between 2015 and 2020 were included as the validation cohort. Serious complications included, among others, abdominal abscess, bowel obstruction, leak, and bleeding. Three risk-prediction models were validated: (1) the original MBSC model from 2011, (2) the original MBSC model including the same variables but updated to more recent patients (2015-2020), and (3) the current MBSC model. The following predictors from the MBSC model were available in the DATO: age, sex, procedure type, cardiovascular disease, and pulmonary disease. Model performance was determined using the area under the curve (AUC) to assess discrimination (i.e., the ability to distinguish patients with events from those without events) and a graphical plot to assess calibration (i.e., whether the predicted absolute risk for patients was similar to the observed prevalence of the outcome). RESULTS: The DATO validation cohort included 51,291 patients. Overall, 986 patients (1.92%) experienced serious complications. The original MBSC model, which was extended with the predictors "GERD (yes/no)," "OSAS (yes/no)," "hypertension (yes/no)," and "renal disease (yes/no)," showed the best validation results. This model had a good calibration and an AUC of .602 compared with an AUC of .65 and moderate to good calibration in the Michigan model. CONCLUSION: The DATO prediction model has good calibration but moderate discrimination. To be used in clinical practice, good calibration is essential to accurately predict individual risks in a real-world setting. Therefore, this model could provide valuable information for bariatric surgeons as part of shared decision making in daily practice.

Hospital Variation in Preference for a Specific Bariatric Procedure and the Association with Weight Loss Performance: a Nationwide Analysis.

PURPOSE: Hospitals performing a certain bariatric procedure in high volumes may have better outcomes. However, they could also have worse outcomes for some patients who are better off receiving another procedure. This study evaluates the effect of hospital preference for a specific type of bariatric procedure on their overall weight loss results. METHODS: All hospitals performing bariatric surgery were included from the nationwide Dutch Audit for Treatment of Obesity. For each hospital, the expected (E) numbers of sleeve gastrectomy (SG), Roux-en-Y gastric bypass (RYGB), and one-anastomosis gastric bypass (OAGB) were calculated given their patient-mix. These were compared with the observed (O) numbers as the O/E ratio in a funnel plot. The 95% control intervals were used to identify outlier hospitals performing a certain procedure significantly more often than expected given their patient-mix (defined as hospital preference for that procedure). Similarly, funnel plots were created for the outcome of patients achieving ≥ 25% total weight loss (TWL) after 2 years, which was linked to each hospital's preference. RESULTS: A total of 34,558 patients were included, with 23,154 patients completing a 2-year follow-up, of whom 79.6% achieved ≥ 25%TWL. Nine hospitals had a preference for RYGB (range O/E ratio [1.09-1.53]), with 1 having significantly more patients achieving ≥ 25%TWL (O/E ratio [1.06]). Of 6 hospitals with a preference for SG (range O/E ratio [1.10-2.71]), one hospital had significantly fewer patients achieving ≥ 25%TWL (O/E ratio [0.90]), and from two hospitals with a preference for OAGB (range O/E ratio [4.0-6.0]), one had significantly more patients achieving ≥ 25%TWL (O/E ratio [1.07]). One hospital had no preference for any procedure but did have significantly more patients achieving ≥ 25%TWL (O/E ratio [1.10]). CONCLUSION: Hospital preference is not consistently associated with better overall weight loss results. This suggests that even though experience with a procedure may be slightly less in hospitals not having a preference, it is still sufficient to achieve similar weight loss outcomes when surgery is provided in centralized high-volume bariatric institutions.

Conversion to Roux-en-Y gastric bypass versus one-anastomosis gastric bypass after a failed primary gastric band: a matched nationwide study.

BACKGROUND: Primary laparoscopic adjustable gastric band (LAGB) has high rates of patients not achieving the desired weight loss, and it remains unclear which bariatric conversion procedure gives better results. OBJECTIVE: To compare weight loss among patients undergoing conversion one-anastomosis gastric bypass (cOAGB) and conversion Roux-en-Y gastric bypass (cRYGB) after a failed LAGB. SETTING: Nationwide population-based study including all 18 hospitals providing metabolic and bariatric surgery. METHODS: Patients with a failed primary LAGB who underwent a cRYGB or cOAGB between January 1, 2015, and December 31, 2019, were selected from the Dutch Audit for Treatment of Obesity. The primary outcome was not achieving ≥20% total weight loss (TWL) at 1-year and up to 5-year follow-up. Secondary outcomes included postoperative complications, defined as Clavien-Dindo ≥III within 30 days, and co-morbidity remission. A propensity score matched logistic and Poisson regression model was used to estimate the difference in patients not achieving ≥20% TWL between cRYGB and cOAGB. RESULTS: A total of 615 (78.7%) patients underwent cRYGB, and 166 (21.3%) patients underwent cOAGB, with 163 patients successfully matched. Both groups had similar rates of patients not achieving ≥20% TWL at 1 year (odds ratio [OR] = .64, 95% confidence interval [CI]: .38-1.05). However, a sensitivity analysis showed that patients undergoing cOAGB had lower rates of patients not achieving ≥20% TWL up to 5-year follow-up (rate ratio = .69, 95% CI: .51-.95, P < .05). Patients undergoing cOAGB were less likely to achieve hypertension remission (OR = .22, 95% CI: .07-.66). There were no significant differences between groups in postoperative complications (OR = .39, 95% CI: .07-2.06, P > .05). CONCLUSION: This matched nationwide study suggests that the cOAGB has similar short-term weight loss outcomes but potentially better long-term weight loss results than cRYGB. Therefore, cOAGB could provide a reliable alternative but needs to be substantiated in future long-term studies.

Impact of the COVID-19 pandemic on surgical care in the Netherlands.

BACKGROUND: The COVID-19 pandemic caused disruption of regular healthcare leading to reduced hospital attendances, repurposing of surgical facilities, and cancellation of cancer screening programmes. This study aimed to determine the impact of COVID-19 on surgical care in the Netherlands. METHODS: A nationwide study was conducted in collaboration with the Dutch Institute for Clinical Auditing. Eight surgical audits were expanded with items regarding alterations in scheduling and treatment plans. Data on procedures performed in 2020 were compared with those from a historical cohort (2018-2019). Endpoints included total numbers of procedures performed and altered treatment plans. Secondary endpoints included complication, readmission, and mortality rates. RESULTS: Some 12 154 procedures were performed in participating hospitals in 2020, representing a decrease of 13.6 per cent compared with 2018-2019. The largest reduction (29.2 per cent) was for non-cancer procedures during the first COVID-19 wave. Surgical treatment was postponed for 9.6 per cent of patients. Alterations in surgical treatment plans were observed in 1.7 per cent. Time from diagnosis to surgery decreased (to 28 days in 2020, from 34 days in 2019 and 36 days in 2018; P < 0.001). For cancer-related procedures, duration of hospital stay decreased (5 versus 6 days; P < 0.001). Audit-specific complications, readmission, and mortality rates were unchanged, but ICU admissions decreased (16.5 versus 16.8 per cent; P < 0.001). CONCLUSION: The reduction in the number of surgical operations was greatest for those without cancer. Where surgery was undertaken, it appeared to be delivered safely, with similar complication and mortality rates, fewer admissions to ICU, and a shorter hospital stay.

COVID-19 has had a significant impact on healthcare worldwide. Hospital visits were reduced, operating facilities were used for COVID-19 care, and cancer screening programmes were cancelled. This study describes the impact of the COVID-19 pandemic on Dutch surgical healthcare in 2020. Patterns of care in terms of changed or delayed treatment are described for patients who had surgery in 2020, compared with those who had surgery in 2018­2019. The study found that mainly non-cancer surgical treatments were cancelled during months with high COVID-19 rates. Outcomes for patients undergoing surgery were similar but with fewer ICU admissions and shorter hospital stay. These data provide no insight into the burden endured by patients who had postponed or cancelled operations.

National Bariatric Surgery Registries: an International Comparison.

INTRODUCTION: Pooling population-based data from all national bariatric registries may provide international real-world evidence for outcomes that will help establish a universal standard of care, provided that the same variables and definitions are used. Therefore, this study aims to assess the concordance of variables across national registries to identify which outcomes can be used for international collaborations. METHODS: All 18 countries with a national bariatric registry who contributed to The International Federation for the Surgery of Obesity and Metabolic Disorders (IFSO) Global Registry report 2019 were requested to share their data dictionary by email. The primary outcome was the percentage of perfect agreement for variables by domain: patient, prior bariatric history, screening, operation, complication, and follow-up. Perfect agreement was defined as 100% concordance, meaning that the variable was registered with the same definition across all registries. Secondary outcomes were defined as variables having "substantial agreement" (75-99.9%) and "moderate agreement" (50-74.9%) across registries. RESULTS: Eleven registries responded and had a total of 2585 recorded variables that were grouped into 250 variables measuring the same concept. A total of 25 (10%) variables have a perfect agreement across all domains: 3 (18.75%) for the patient domain, 0 (0.0%) for prior bariatric history, 5 (8.2%) for screening, 6 (11.8%) for operation, 5 (8.8%) for complications, and 6 (11.8%) for follow-up. Furthermore, 28 (11.2%) variables have substantial agreement and 59 (23.6%) variables have moderate agreement across registries. CONCLUSION: There is limited uniform agreement in variables across national bariatric registries. Further alignment and uniformity in collected variables are required to enable future international collaborations and comparison.

Metabolic effects of bariatric surgery on patients with type 2 diabetes: a population-based study.

BACKGROUND: Bariatric surgery among patients with obesity and type 2 diabetes (T2D) can induce complete remission. However, it remains unclear whether sleeve gastrectomy (SG) or Roux-en-Y gastric bypass (RYGB) has better T2D remission within a population-based daily practice. OBJECTIVES: To compare patients undergoing RYGB and SG on the extent of T2D remission at the 1-year follow-up. SETTING: Nationwide, population-based study including all 18 hospitals in the Netherlands providing metabolic and bariatric surgery. METHODS: Patients undergoing RYGB and SG between October 2015 and October 2018 with 1 year of complete follow-up data were selected from the mandatory nationwide Dutch Audit for Treatment of Obesity (DATO). The primary outcome is T2D remission within 1 year. Secondary outcomes include ≥20% total weight loss (TWL), obesity-related co-morbidity reduction, and postoperative complications with a Clavien-Dindo (CD) grade ≥III within 30 days. We compared T2D remission between RYGB and SG groups using propensity score matching to adjust for confounding by indication. RESULTS: A total of 5015 patients were identified from the DATO, and 4132 (82.4%) had completed a 1-year follow-up visit. There were 3350 (66.8%) patients with a valid T2D status who were included in the analysis (RYGB = 2623; SG = 727). RYGB patients had a lower body mass index than SG patients, but were more often female, with higher gastroesophageal reflux disease and dyslipidemia rates. After adjusting for these confounders, RYGB patients had increased odds of achieving T2D remission (odds ratio [OR], 1.54; 95% confidence interval [CI], 1.14-2.1; P < .01). Groups were balanced after matching 695 patients in each group. After matching, RYGB patients still had better odds of T2D remission (OR, 1.91; 95% CI, 1.27-2.88; P < .01). Also, significantly more RYGB patients had ≥20%TWL (OR, 2.71; 95% CI, 1.96-3.75; P < .01) and RYGB patients had higher dyslipidemia remission rates (OR, 1.96; 95% CI, 1.39-2.76; P < .01). There were no significant differences in CD ≥III complications. CONCLUSION: Using population-based data from the Netherlands, this study shows that RYGB leads to better T2D remission rates at the 1-year follow-up and better metabolic outcomes for patients with obesity and T2D undergoing bariatric surgery in daily practice.

Prognostic tools for hypertrophic scar formation based on fundamental differences in systemic immunity.

Unpredictable hypertrophic scarring (HS) occurs after approximately 35% of all surgical procedures and causes significant physical and psychological complaints. Parallel to the need to understanding the mechanisms underlying HS formation, a prognostic tool is needed. The objective was to determine whether (systemic) immunological differences exist between patients who develop HS and those who develop normotrophic scars (NS) and to assess whether those differences can be used to identify patients prone to developing HS. A prospective cohort study with NS and HS groups in which (a) cytokine release by peripheral blood mononuclear cells (PBMC) and (b) the irritation threshold (IT) after an irritant (sodium lauryl sulphate) patch test was evaluated. Univariate regression analysis of PBMC cytokine secretion showed that low MCP-1, IL-8, IL-18 and IL-23 levels have a strong correlation with HS (P < .010-0.004; AUC = 0.790-0.883). Notably, combinations of two or three cytokines (TNF-a, MCP-1 and IL-23; AUC: 0.942, Nagelkerke R2 : 0.727) showed an improved AUC indicating a better correlation with HS than single cytokine analysis. These combination models produce good prognostic results over a broad probability range (sensitivity: 93.8%, specificity 86.7%, accuracy 90,25% between probability 0.3 and 0.7). Furthermore, the HS group had a lower IT than the NS group and an accuracy of 68%. In conclusion, very fundamental immunological differences exist between individuals who develop HS and those who do not, whereas the cytokine assay forms the basis of a predictive prognostic test for HS formation, the less invasive, easily performed irritant skin patch test is more accessible for daily practice.