Evidence mapPaperPMID 42398077Full record

ArticleBJS open2026

Development of a predictive model for postoperative body mass index and diabetes outcomes after metabolic bariatric surgery: retrospective cohort study.

Vincent Ochs, Lars Kollmann, Ilan Rosenblum, Adisa Poljo, Andreas Heule, Bassey Enodien, Maryna Chumakova-Orin, Eric J DeMaria, Emanuel Burri, Reinhard Stoll and 27 more

Abstract readMulticenter Study
In one paragraph

Article in BJS open, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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1 · What the graph read from it

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2 · The registry

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3 · Its place in the literature

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4 · The record

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5 · Who and what money

Authors and funding

37 authors.

Vincent OchsDepartment of Biomedical Engineering, Faculty of Medicine, University of Basel, Basel, Switzerland.
Lars KollmannDepartment of General, Visceral, Transplantation, Vascular, and Pediatric Surgery, University Hospital Wuerzburg, Wuerzburg, Germany.
Ilan RosenblumDepartment of Visceral Surgery, Cantonal Hospital Baselland, Liestal, Switzerland.
Adisa PoljoClarunis, Department of Visceral Surgery, University Center for Gastrointestinal and Liver Diseases, St.Clara Hospital and University Hospital Basel, Basel, Switzerland.
Andreas HeuleDepartment of Biomedical Engineering, Faculty of Medicine, University of Basel, Basel, Switzerland.
Bassey EnodienDepartment of Surgery, Cantonal Hospital Glarus, Glarus, Switzerland.
Maryna Chumakova-OrinDepartment of Surgery, East Carolina University, Brody School of Medicine, Greenville, North Carolina, USA.
Eric J DeMariaDepartment of Surgery, East Carolina University, Brody School of Medicine, Greenville, North Carolina, USA.
Emanuel BurriUniversity Institute of Internal Medicine, Cantonal Hospital Baselland, Liestal, Switzerland.
Reinhard StollClarunis, Department of Visceral Surgery, University Center for Gastrointestinal and Liver Diseases, St.Clara Hospital and University Hospital Basel, Basel, Switzerland.
Otto KollmarClarunis, Department of Visceral Surgery, University Center for Gastrointestinal and Liver Diseases, St.Clara Hospital and University Hospital Basel, Basel, Switzerland.
Robert RosenbergClarunis, Department of Visceral Surgery, University Center for Gastrointestinal and Liver Diseases, St.Clara Hospital and University Hospital Basel, Basel, Switzerland.
Pascal ProbstDepartment of Surgery, Cantonal Hospital Thurgau, Frauenfeld, Switzerland.ORCID 0000-0002-0895-4015
Markus K MullerDepartment of Surgery, Cantonal Hospital Thurgau, Frauenfeld, Switzerland.
Stephanie Taha-MehlitzJohannes Kepler University Linz, Medical Faculty, Linz, Austria.
Beat P MüllerJohannes Kepler University Linz, Medical Faculty, Linz, Austria.
Daniel M FreyDepartment of Surgery, Kantonspital Baden, Baden, Switzerland.
Piotr KalinowskiDepartment of General, Transplant and Liver Surgery, Medical University of Warsaw, Warsaw, Poland.
Marta PrzybyszDepartment of General, Transplant and Liver Surgery, Medical University of Warsaw, Warsaw, Poland.
Mateusz BartkowiakDepartment of General, Transplant and Liver Surgery, Medical University of Warsaw, Warsaw, Poland.
Muhammed Said DalkilicDepartment of General Surgery, Marmara University Faculty of Medicine, Istanbul, Turkey.
Abdullah SisikDepartment of General Surgery, Marmara University Faculty of Medicine, Istanbul, Turkey.
Rodrigo Otavio Carvalho De OliveriaiNOVA4Health, NOVA Medical School, Faculty of Medical Sciences, NOVA University of Lisbon, Lisbon, Portugal.
Fatima MartinsiNOVA4Health, NOVA Medical School, Faculty of Medical Sciences, NOVA University of Lisbon, Lisbon, Portugal.
Erik StenbergDepartment of Surgery, Faculty of Medicine and Health, Örebro University, Örebro, Sweden.ORCID 0000-0001-9189-0093
Ellen AnderssonDepartment of Surgery and Department of Clinical and Experimental Medicine, Linköping University, Norrköping, Sweden.ORCID 0000-0001-6533-8166
Torsten OlbersDepartment of Surgery and Department of Clinical and Experimental Medicine, Linköping University, Norrköping, Sweden.ORCID 0000-0002-7218-3390
Sven FlemmingDepartment of General, Visceral, Transplantation, Vascular, and Pediatric Surgery, University Hospital Wuerzburg, Wuerzburg, Germany.ORCID 0000-0002-6304-3169
Florian SeyfriedDepartment of General, Visceral, Transplantation, Vascular, and Pediatric Surgery, University Hospital Wuerzburg, Wuerzburg, Germany.
Florian PonholzerDepartment of Visceral, Transplant and Thoracic Surgery, Center of Operative Medicine, Medical University of Innsbruck, Innsbruck, Austria.
Annemarie WeissenbacherDepartment of Visceral, Transplant and Thoracic Surgery, Center of Operative Medicine, Medical University of Innsbruck, Innsbruck, Austria.ORCID 0000-0002-0582-1815
Dietmar ÖfnerDepartment of Visceral, Transplant and Thoracic Surgery, Center of Operative Medicine, Medical University of Innsbruck, Innsbruck, Austria.ORCID 0000-0001-8909-8566
Johanna BetzlerDepartment of Surgery, University Medical Center Mannheim, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany.ORCID 0009-0004-0159-3212
Mirko OttoDepartment of Surgery, University Medical Center Mannheim, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany.
Ralph PeterliDepartment Clinical Research, University of Basel, Basel, Switzerland.
Philippe C CattinDepartment of Biomedical Engineering, Faculty of Medicine, University of Basel, Basel, Switzerland.
Anas TahaDepartment of Biomedical Engineering, Faculty of Medicine, University of Basel, Basel, Switzerland.

Funding

Vontobel foundation 0132/2024
6 · The paper itself

Abstract

backgroundPredicting postoperative body mass index (BMI) trajectories and long-term type 2 diabetes (T2D) remission after bariatric surgery remains challenging. Existing models often rely on baseline variables only and fail to incorporate dynamic postoperative changes. This study aimed to develop and validate a multicentre machine-learning framework that predicts individualized BMI trajectories and T2D remission using routinely available preoperative data and time-dependent weight evolution.

methodsThis multicentre retrospective cohort study included adult patients who underwent Roux-en-Y gastric bypass or sleeve gastrectomy across 11 European centres (2012-2023). Variables with > 30% missing data were excluded; remaining missing values were imputed iteratively. A two-stage approach was used: a regression model predicting postoperative BMI at 3-60 months using an autoregressive design; and a classification model predicting T2D remission using baseline features and predicted BMI trajectories. Internal performance was evaluated with ten-fold and leave-one-clinic-out cross-validation; external validation used an independent cohort from Linköping, Sweden.

resultsOf the 11 457 patients initially identified, 9652 patients with complete baseline and follow-up information were used for the analysis. The best BMI model (HistGradientBoosting) achieved a root mean square error (RMSE) of 1.11 kg/m2 (95% confidence interval 1.07 to 1.14) and a mean absolute error (MAE) of 0.62 kg/m2 across clinics; external testing showed an RMSE of 1.12 kg/m2 (95% confidence interval 1.11 to 1.12) and an MAE of 0.63 kg/m2. The T2D remission classifier (XGBoost) obtained a Macro F1 score of 0.88 (precision 0.87, recall 0.88), with an external F1 score of 0.89. Incorporating predicted BMI trajectories improved discrimination compared with baseline-only models (C-index 0.95 versus 0.93).

conclusionA two-stage machine-learning framework has high predictive performance for postoperative BMI and T2D remission up to 5 years after bariatric surgery. Dynamic incorporation of predicted weight trajectories enhances metabolic risk prediction and supports individualized counselling and postoperative management.

Indexed as

Bariatric SurgeryBody Mass IndexDiabetes Mellitus, Type 2AdultFemaleGastrectomyGastric BypassHumansMaleMiddle AgedPostoperative PeriodPrediction AlgorithmsPredictive Learning ModelsRetrospective StudiesWeight Lossdiabetes remissionmachine learningpostoperative weight lossrisk prediction

Identifiers

PMID42398077
PMCPMC13331347

What Socratic holds

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the Socratic graph.