International expert consensus on surgery for type 2 diabetes mellitus

Kermansaravi, Mohammad and Omar, Islam and Finer, Nicholas and Le Roux, Carel and Carbajo, Miguel A and Sarwer, David and Busetto, Luca and Ponce, Jaime and Logue, Jennifer and Parretti, Helen M and O'Kane, Mary and Shahabi, Shahab and Khunti, Kamlesh and Blakemore, Alexandra I and Stenberg, Erik and Abbott, Sally and Alqahtani, Aayed and Aminian, Ali and Amr, Bassem and Balibrea, Jose M and Batterham, Rachel L and Behrens, Estuardo and Bhatt, Deepak L and Chesworth, Paul and Chowbey, Pradeep and Clare, Ken and Neto, Manoel Galvao and Graham, Yitka and Goel, Ramen and Hanif, Wasim and Herrera, Miguel F and Kasama, Kazunori and Kassir, Radwan and Knop, Filip K and Kothari, Shanu N and Kristinsson, Jon A and McGowan, Barbara and McKechnie, Andrew and Miller, Karl and Miras, Alex D and Morton, John and Ogden, Jane and Peterli, Ralph and Pinkney, Jonathan H and Pournaras, Dimitri and Pouwels, Sjaak and Prager, Gerhard and Salminen, Paulina and Serlie, Mireille J and Shabbir, Asim and Singhal, Rishi and Taheri, Shahrad and Tahrani, Abd A and Weiner, Rudolf and Shikora, Scott A and Mahawar, Kamal (2025) International expert consensus on surgery for type 2 diabetes mellitus. BMC Endocrine Disorders, 25 (1): 151. ISSN 1472-6823

Abstract

INTRODUCTION: Metabolic and bariatric surgery (MBS) has been an established treatment option for patients with Type 2 diabetes mellitus (T2DM), but there is a relative paucity of evidence-based guidelines on preoperative, operative, and postoperative considerations concerning metabolic surgery for T2DM patients. To address this gap, we initiated a Delphi consensus process with a diverse group of international multidisciplinary experts. METHOD: We embarked on a Delphi consensus-building exercise to propose an evidence-based expert consensus covering various aspects of MBS in patients with T2DM. We defined the scope of the exercise and proposed statements and surveyed the literature through electronic databases. The literature summary and voting process were conducted by 52 experts, who evaluated 44 statements. The quality of evidence was assessed using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) criteria. RESULTS: Consensus, defined as > 80% agreement, was reached for 43 out of 44 statements. The experts reached an agreement on the nature, terminology, and mechanisms of action of MBS. The currently available scores for predicting remission of T2DM after surgery are not robust enough for routine clinical use, and there is a need for further research to enable more personalized treatment. Additionally, they agreed that metabolic surgery for T2DM is cost-effective, and MBS procedures for treating T2DM vary in their safety and efficacy. CONCLUSION: This Delphi expert consensus statement guides clinicians on various aspects of metabolic surgery for T2DM and also grades the quality of the available evidence for each of the proposed statements.