Thirty-day morbidity and mortality of bariatric and metabolic surgery in patients with type 2 diabetes mellitus: A subset analysis of the GENEVA cohort study

Rishi Singhal; Victor Roth Cardoso; Christian Ludwig; Jonathan Super; Yashasvi Rajeev; Gavin Rudge; Georgios V Gkoutos; Kamal Mahawar; GENEVA collaborators

doi:10.4103/jbs.jbs_1_21

ORIGINAL ARTICLE

Year : 2022 | Volume : 1 | Issue : 1 | Page : 34-41

Thirty-day morbidity and mortality of bariatric and metabolic surgery in patients with type 2 diabetes mellitus: A subset analysis of the GENEVA cohort study

Rishi Singhal¹, Victor Roth Cardoso², Christian Ludwig³, Jonathan Super⁴, Yashasvi Rajeev⁵, Gavin Rudge⁶, Georgios V Gkoutos⁷, Kamal Mahawar⁸, GENEVA collaborators⁹
¹ Department of General Surgery, Upper GI Unit, University Hospital Birmingham NHS Foundation Trust, West Midlands, United Kingdom
² Institute of Cancer and Genomic Sciences, University of Birmingham, West Midlands; Health Data Research UK Midlands, Birmingham, United Kingdom
³ Institute of Metabolism and Systems Research, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
⁴ Department of General Surgery, Maidstone and Tunbridge Wells NHS Trust, Royal Tunbridge Wells, Harrow, London, United Kingdom
⁵ Department of Surgery, London Northwest University Healthcare NHS Trust, Harrow, London, United Kingdom
⁶ Institute of Applied Health Research, Murray Learning Centre, University of Birmingham, Birmingham, United Kingdom
⁷ Institute of Cancer and Genomic Sciences, University of Birmingham, West Midlands; Health Data Research UK Midlands; NIHR Biomedical Research Centre; NIHR Surgical Reconstruction and Microbiology Research Centre, Birmingham, United Kingdom
⁸ Department of General Surgery, Bariatric Unit, South Tyneside and Sunderland NHS Trust, Sunderland, United Kingdom

Date of Submission	23-Sep-2021
Date of Acceptance	16-Dec-2021
Date of Web Publication	09-Mar-2022

Correspondence Address:
Rishi Singhal
Department of General Surgery, Upper GI Unit, University Hospital Birmingham NHS Foundation Trust, Birmingham
United Kingdom

Source of Support: None, Conflict of Interest: None

DOI: 10.4103/jbs.jbs_1_21

Abstract

Introduction: There is a paucity of data in the scientific literature on the morbidity and mortality of bariatric and metabolic surgery (BMS) in individuals suffering from Type 2 diabetes mellitus (T2D). The current study is a secondary analysis of the GENEVA dataset to understand this. Materials and Methods: Logistic regressions were performed to investigate the influence of diabetes on complication rates and procedure selection. Ethical approval was not required. Results: One thousand four hundred and seventy-five of these patients were suffering from T2D at the time of the surgery (416 diet-treated type 2 diabetes), 806 oral agent-treated type 2 diabetes, and 253 insulin-treated type 2 diabetes [ITD]). Six hundred and fifty (44.1%) of these patients underwent laparoscopic sleeve gastrectomy (LSG); 487 (33%) underwent Roux-en-Y gastric bypass; 230 (15.6%) underwent a one anastomosis gastric bypass (OAGB); and 108 (7.3%) underwent some other procedures. The 30-day mortality of BMS in those without T2D was 0.07% (4/5609) as compared to 0.4% (6/1475) and 0.8% (2/253) in those with T2D and ITD, respectively. 7.9% of those with T2D developed a 30-day complication compared to 6.5% without T2D (P = 0.0475). There was an increased risk of complications in patients with ITD on univariate and multivariate analysis. Patients with T2D were significantly less likely to undergo an LSG and significantly more likely to undergo an OAGB. Conclusions: ITD patients undergoing BMS experienced significantly higher 30-day morbidity and mortality. Although LSG was the most common procedure in patients with T2D, these patients were less likely to undergo LSG than patients without T2D.

Keywords: Bariatric surgery, coronavirus disease-2019, diabetes surgery, gastric banding, gastric bypass, metabolic surgery, obesity surgery, obesity, pandemic, sleeve gastrectomy, type 2 diabetes mellitus

How to cite this article:
Singhal R, Cardoso VR, Ludwig C, Super J, Rajeev Y, Rudge G, Gkoutos GV, Mahawar K, GENEVA collaborators. Thirty-day morbidity and mortality of bariatric and metabolic surgery in patients with type 2 diabetes mellitus: A subset analysis of the GENEVA cohort study. J Bariatr Surg 2022;1:34-41

How to cite this URL:
Singhal R, Cardoso VR, Ludwig C, Super J, Rajeev Y, Rudge G, Gkoutos GV, Mahawar K, GENEVA collaborators. Thirty-day morbidity and mortality of bariatric and metabolic surgery in patients with type 2 diabetes mellitus: A subset analysis of the GENEVA cohort study. J Bariatr Surg [serial online] 2022 [cited 2023 Sep 29];1:34-41. Available from: http://www.jbsonline.org/text.asp?2022/1/1/34/339260

Introduction

Bariatric and metabolic surgery (BMS) for patients suffering from type 2 diabetes mellitus (T2D) and obesity is now supported by many guidelines.^[1],[2] This is on the back of high-quality data showing superior efficacy of BMS compared to medical management in the treatment of T2D.^[3] However, most of these studies are powered to evaluate the efficacy and there is no randomized controlled trial (RCT) in the scientific literature comparing treatment-related or all-cause morbidity and mortality as the primary endpoints. This makes it difficult for patients and health-care practitioners to make a truly informed choice.

Similarly, though there are many large datasets^[4],[5] that allow us to understand the 30 day morbidity and mortality of BMS in general, there is none that focus on patients with T2D. Studies focussing on patients with T2D tend to examine mortality benefits over prolonged periods^[6],[7],[8] and do not focus on 30-day morbidity and mortality, a widely recognized outcome measure for examining surgical safety. To the best of our knowledge, there is only one study in the literature that reports on 30-day morbidity and mortality of patients with T2D undergoing either a laparoscopic sleeve gastrectomy (LSG) or Roux-en-Y gastric bypass (RYGB).^[9] This analysis of the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP) database in the United States does not include other increasingly popular procedures such as one anastomosis gastric bypass (OAGB), also includes revisional procedures, and is by definition national data.

Patients with T2D and obesity form an especially interesting subset of those undergoing BMS as both their clinical conditions can be expected to improve significantly after surgery. Potentially, therefore, this group stands more to gain from BMS. At the same time, patients with T2D can also be at a higher risk of 30-day morbidity and mortality^[10],[11] when undergoing any surgical procedure. Whether or not this is also true of patients undergoing primary BMS needs to be determined to allow patients and health-care providers to be able to engage in a truly informed discussion.

The GENEVA multinational cohort showed that 30-day morbidity and mortality of BMS during the coronavirus disease-2019 (COVID-19) pandemic were similar to the prepandemic data.^[12] The current study is a secondary analysis of the GENEVA data focussing on patients with T2D. This analysis aimed to understand the 30-day morbidity and mortality of primary BMS in patients with T2D and its various subgroups – such as diet-treated type 2 diabetes (DTD), oral agent-treated type 2 diabetes (OATD), and insulin-treated type 2 diabetes (ITD). A secondary aim was to analyze the effect of diabetes and other clinical parameters on the choice of surgical procedure.

Materials and Methods

Study design and population

We conducted a global, multicentre, observational cohort study of BMS (elective primary, elective revisional, and emergency) in adults (≥18 years) performed between May 1, 2020, and October 31, 2020. The participating centers and surgeons were contacted using personal networks, national societies, and bariatric professionals' networks on social media; this project was registered as a multinational audit.

Data collected and handling

Complications were captured using the Clavien–Dindo (CD) Classification system for reporting surgical complications.^[13] This allowed for easier comparison of complication data and captured all complications irrespective of their severity. We further captured individual complications that would be important to the bariatric community such as bleeding and leak rates and complications such as chest infection/pneumonia that would be important in the context of the COVID-19 pandemic. In the case of more than one complication occurring in the same patient, the highest CD score was reported. Study data were collected and managed using research electronic data capture tools.

Statistical methods

Continuous data were presented as mean ± standard deviation or median (interquartile range) depending on data distribution. Frequencies were used to summarize categorical variables. Independent t-test or Mann–Whitney U test was used to examine differences between continuous variables depending on data distribution. A Fisher's exact test or Chi-square test was used to compare categorical variables as appropriate. Statistical analysis was performed using Statistical Product and Service Solutions (SPSS; IBM Corp. Released 2020. IBM SPSS Statistics for Windows, Version 27.0. Armonk, NY: IBM Corp).

Logistic regressions were performed to investigate the effect of T2D on the surgery selection process, where the outcome variable was the specific surgery type against the others, and to investigate the influence of T2D on complications. These regressions included type of diabetes and were adjusted by the following variables: age, sex, body mass index (BMI), smoking status, ethnicity, obstructive sleep apnea (OSA), hypercholesterolemia, hypertension, and “other” comorbidity. Multivariate models were created using a generalized linear model in R.^[14] The multivariate model coefficients for each variable were used to calculate the odds ratio (OR) and its confidence interval. The OR was used to assess the likelihood of a patient developing complications perioperatively.

Sensitivity analysis

The matching of patients was performed using propensity score matching in a stepwise approach. Patients with ITD were matched with OATD, DTD, and those without T2D independently. The variables used for matching were: age, sex, BMI, smoking status, ethnicity, OSA, hypercholesterolemia, hypertension, and “other” comorbidity. This procedure was performed in R (R Core Team 2021) using the Matchit package.^[14],[15] The distance was calculated using Mahalanobis distance, estimating the distribution that is closest to a point,^[16] matching on the nearest one. Following this, a multivariate model was created similar to the multivariate model prior to matching.

Results

A total of 470 surgeons from 179 centers in 42 countries submitted data on 7092 adult patients who underwent primary BMS between May 1, 2020, and October 31, 2020, at the participating centers. Of these, complete 30-day morbidity and mortality data were available for 7084 (99.88%) by December 10, 2020.

Basic demographics

One thousand four hundred and seventy-five of these patients had T2D at the time of the surgery (416 DTD, 806 OATD, and 253 ITD). [Table 1] provides basic demographic characteristics and comorbidities for all patients with T2D and its various subgroups. Six hundred and fifty (44.1%) of these patients underwent LSG; 487 (33%) underwent RYGB; 230 (15.6%) underwent a OAGB; and 108 (7.3%) underwent some other procedures.

Table 1: Basic demographic details of all patients undergoing elective primary BMS described according to their diabetes status

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Mortality and morbidity

The 30-day mortality of BMS in those without T2D was 0.07% (4/5609) as compared to 0.4% (6/1475) and 0.8% (2/253) in those with T2D or ITD, respectively. This difference was statistically significant (P = 0.0079 and P = 0.0251, respectively; Fisher's exact test).

7.9% of those with T2D developed a 30-day complication compared to 6.5% without T2D (P = 0.0475; Fisher's exact test). [Table 2] provides a full breakdown of different complications according to CD Grade as well as complication type for patients with and without T2D and subgroups of those with T2D.

Table 2: 30-day morbidity and mortality of elective primary BMS described according to their diabetes status

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Factors influencing postoperative complications

On univariate analysis, there was a strong association between ITD and postoperative complications (OR = 1.07 [1.04–1.1]; P < 0.0001). This association was not seen with OATD or DTD. On multivariate analysis [Figure 1]a, adjusting for age, sex, and BMI, the increased risk of complications in patients with ITD was maintained (OR = 1.06 [1.02–1.09]; P = 0.001). An increased risk was also identified in patients with increasing age, smokers, patients with hypercholesterolemia, or with OSA not currently on continuous positive airway pressure. Patients undergoing RYGB were also exposed to an increased risk of complications (OR = 1.02 [1–1.03]; P = 0.009). Patients with OATD had an apparent reduction in risk of complications on multivariate analysis (OR: 0.97 [0.96–0.99]; P = 0.03). However, when the data were matched for baseline characteristics [Figure 1]b, this reduction was not seen (OR: 0.99 [0.95–1.05]; P = 0.95).

Figure 1: Forest plot showing the effect of baseline characteristics on the risk of developing complications before (a) and after (b) matching

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Choice of procedure

About 44.1% of patients with T2D (n = 649/1470) underwent an LSG as opposed to 59.5% (n = 3334/5600) of those without. Interestingly, only 29.8% (75/252) of ITD patients underwent an LSG. On univariate analysis, if the patient had any type of T2D, there was a tendency to not have LSG (P < 0.00001). On multivariate analysis [Table 3], for patients with T2D, even after adjusting for all other variables, there was still a significant difference in the selection of surgery. Patients with T2D were significantly less likely to undergo an LSG and significantly more likely to undergo an OAGB (OR: 0.89 [0.87–0.92, P < 0.00001). When assessing the choice of RYGB while adjusting for other variables, the tendency to have RYGB was maintained only for ITD (OR: 1.06 [1.002–1.12]; P = 0.04).

Table 3: Multivariate regression analysis for the factors influencing the choice of procedure

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Postoperative coronavirus disease-2019

The rate of postoperative symptomatic COVID-19 in patients without T2D (0.5%; n = 30/5609) was similar to patients with T2D (0.5%; n = 8/1475) [Table 4]. Among those with T2D, risk was highest for ITD group (1.6%; n = 4/253). This difference among the four groups (those without diabetes, DTD, OATD, and ITD) was statistically significant (P = 0.039).

Table 4: Diagnosis of symptomatic postoperative coronavirus disease-2019 according to T2D status

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Discussion

This is the first global study reporting on 30-day morbidity and mortality of primary BMS for patients with T2D. We found that 30-day morbidity of BMS in patients with T2D was 6.9% and 30-day mortality was 0.4% (6/1475). Among those with T2D, 30-day morbidity and mortality were highest for ITD patients at 13.0% and 0.8% (2.253), respectively. In comparison, these figures were 6.5% and 0.07% (4/5609), respectively, for those without T2D. 30-day mortality in those without T2D was significantly lower than those with T2D and those with ITD. Patients with T2D were more likely to experience 30-day morbidity or mortality in comparison with those without T2D. On subgroup analyses, the differences were only significant for those with ITD.

There are concerns that BMS is not adequately used for patients with T2D^[17] despite data showing its cost-effectiveness, particularly for those needing insulin.^[18] One of the potential explanations for lower utilization of BMS could be the morbidity and mortality associated with the surgical procedure itself. Given that patients with T2D are known to be at a higher risk of 30-day morbidity and mortality for many surgical specialties, one could assume that the available data on 30-day morbidity and mortality of BMS do not apply to those with T2D. Our findings would further support this notion.

Leonard-Murali et al.^[9] found that 30-day mortality of LSG was 0.15% for ITD patients, 0.09% for OATD patients, and 0.04% for those without T2D. In comparison, corresponding figures in our study were 1.33% (1/75), 0/371, and 0.06% (2/3338), respectively. For RYGB, the 30-day mortality in the study by Leonard-Murali et al.^[9] was 0.24% for ITD patients, 0.14% for OATD patients, and 0.1% for those without T2D. In our study, there were no mortalities for RYGB in any of these groups. Just like our study, they also found the complication rate to be higher in those with T2D in comparison with those without T2D. And like us, they found the complication rate to be highest for ITD patients. In modeling from the MBSAQIP database, Wise et al.^[19] also found diabetes to be associated with a higher 30-day complication rate with LSG, but this study did not report any real data.

We found that patients with T2D were more likely to undergo OAGB. This is probably because this procedure has been shown to have superior metabolic efficacy in comparison with either RYGB^[20] or LSG.^[21] RYGB seemed to be preferred over LSG in ITD patients, once again probably because it appears to have a superior metabolic profile in comparison with LSG.^[22] Differences in metabolic efficacies of different bariatric procedures are not very obvious from individual RCTs,^[23] as they tend to have weight loss as their endpoints and are not sufficiently powered to evaluate differences in diabetes resolution rates.

The postoperative COVID-19 rate in the GENEVA cohort study was very low at 0.5%.^[12] In this study, we did not find any difference in postoperative COVID-19 rates in those with diabetes and those without. This is in contrast to Axiotakis et al.^[24] who found perioperative infection to be associated with preoperative diabetes (OR: 3.70, P = 0.042). We did however find that patients with ITD were significantly more likely to have postoperative COVID-19 in comparison with other groups [Table 4]. Since in this study we have only focussed on symptomatic postoperative COVID-19, we cannot say if ITD patients are more likely to acquire the virus postoperatively or more likely to develop the clinically apparent infection. Others have also found diabetes to be associated with poorer outcomes with COVID-19.^[25]

Strengths and weaknesses

This paper adds to the scarce literature on 30-day morbidity and mortality of BMS in patients with T2D and its various subgroups. The global reach of our data, inclusion of various procedures, a high 30-day data completion rate of 99.5%, and its relevance to the ongoing pandemic make our findings important. Another limitation of the study was that data about the duration of T2D were not captured since the aim of this study was analyzing short-term outcomes of BMS. At the same time, nonrandomized nature of the study and self-reported complication rates mean our findings need further confirmation.

Conclusions

ITD patients undergoing BMS experience significantly higher 30-day morbidity and mortality. Patients with T2D are significantly more likely to undergo an OAGB and less likely to undergo an LSG.

Financial support and sponsorship

This study was financially supported by Bariatric Unit, University Hospitals Birmingham NHS Foundation Trust.

Conflicts of interest

There are no conflicts of interest.

Geneva Collaborators

Michał Pędziwiatr¹, Piotr Major¹, Piotr Zarzycki¹, Athanasios Pantelis², Dimitris P. Lapatsanis², Georgios Stravodimos², Chris Matthys³, Marc Focquet³, Wouter Vleeschouwers³, Antonio G Spaventa⁴, Carlos Zerrweck⁴, Antonio Vitiello⁵, Giovanna Berardi⁵, Mario Musella⁵, Alberto Sanchez-Meza⁶, Felipe J Cantu Jr⁶, Fernando Mora⁶, Marco A Cantu⁶, Abhishek Katakwar⁷, D Nageshwar Reddy⁷, Haitham Elmaleh⁸, Mohammad Hassan⁸, Abdelrahman Elghandour⁸, Mohey Elbanna⁸, Ahmed Osman⁸, Athar Khan⁹, Laurent layani⁹, Nalini kiran⁹, Andrey Velikorechin¹⁰, Maria Solovyeva¹⁰, Hamid Melali¹¹, Shahab Shahabi¹¹, Ashish Agrawal¹², Apoorv Shrivastava¹², Ankur Sharma¹³, Bhavya Narwaria¹³, Mahendra Narwaria¹³, Asnat Raziel¹⁴, Nasser Sakran¹⁴, Sergio Susmallian¹⁴, Levent Karagöz¹⁵, Murat Akbaba¹⁵, Salih Zeki Pişkin¹⁵, Ahmet Ziya BALTA¹⁶, Zafer Senol¹⁶, Emilio Manno¹⁷, Michele Giuseppe Iovino¹⁷, Ahmed Osman¹⁸, Mohamed Qassem¹⁸, Sebastián Arana-Garza¹⁹, Heitor P. Povoas²⁰, Marcos Leão Vilas-Boas²⁰, Alan Li²¹, Basil J Ammori²², Hany Balamoun²³, Mohammed Salman²³, Amrit Manik Nasta²⁴, Ramen Goel²⁴, Hugo Sánchez-Aguilar²⁴, Miguel F Herrera²⁴, Adel ABOU-MRAD²⁵, Lucie CLOIX²⁵, Guilherme Silva Mazzini²⁶, Leonardo Kristem²⁶, Andre Lazaro²⁷, Jose Campos²⁷, Joaquín Bernardo²⁸, Jesús González²⁸, Carlos Trindade²⁹, Octávio Viveiros²⁹, Rui Ribeiro²⁹, David Goitein³⁰, David Hazzan³⁰, Lior Segev³⁰, Tamar Beck³⁰, Hernán Reyes³¹, Jerónimo Monterrubio³¹, Paulina García³¹, Marine Benois³², Radwan Kassir³², Alessandro Contine³³, Moustafa Elshafei³⁴, Sueleyman Aktas³⁴, Sylvia Weiner³⁴, Till Heidsieck³⁴, Luis Level³⁵, Silvia Pinango³⁵, Patricia Martinez Ortega³⁶, Rafael Moncada³⁶, Victor Valenti³⁶, Ivan Vlahović³⁷, Zdenko Boras³⁷, Arnaud Liagre³⁸, Francesco Martini³⁸, Gildas Juglard³⁸, Manish Motwani³⁹, Sukhvinder Singh Saggu³⁹, Hazem Al Momani⁴⁰, Luis Adolfo Aceves López⁴¹, María Angelina Contreras Cortez⁴¹, Rodrigo Aceves Zavala⁴¹, Christine D'Haese RN⁴², Ivo Kempeneers⁴², Jacques Himpens⁴², Andrea Lazzati⁴³, Luca Paolino⁴³, Sarah Bathaei⁴³, Abdulkadir Bedirli⁴⁴, Aydın Yavuz⁴⁴, Çağrı Büyükkasap⁴⁴, Safa Özaydın⁴⁴, Andrzej Kwiatkowski⁴⁵, Katarzyna Bartosiak⁴⁵, Maciej Walędziak⁴⁵, Antonella Santonicola⁴⁶, Luigi Angrisani⁴⁶, Paola Iovino⁴⁶, Rossella Palma⁴⁶, Angelo Iossa⁴⁷, Cristian Eugeniu Boru⁴⁷, Francesco De Angelis⁴⁷, Gianfranco Silecchia⁴⁷, Abdulzahra Hussain⁴⁸, Srivinasan Balchandra⁴⁸, Izaskun Balciscueta Coltell⁴⁹, Javier Lorenzo Pérez⁴⁹, Ashok Bohra⁵⁰, Altaf K Awan⁵⁰, Brijesh Madhok⁵⁰, Paul C Leeder⁵⁰, Sherif Awad⁵⁰, Waleed Al-Khyatt⁵⁰, Ashraf Shoma⁵¹, Hosam Elghadban⁵¹, Sameh Ghareeb⁵¹, Bryan Mathews⁵², Marina Kurian⁵², Andreas Larentzakis⁵³, Gavriella Zoi Vrakopoulou⁵³, Konstantinos Albanopoulos⁵³, Ahemt Bozdag⁵⁴, Azmi Lale⁵⁴, Cuneyt Kirkil⁵⁴, Mursid Dincer⁵⁴, Ahmad Bashir⁵⁵, Ashraf Haddad⁵⁵, Leen Abu Hijleh⁵⁵, Bruno Zilberstein⁵⁶, Danilo Dallago de Marchi⁵⁶, Willy Petrini Souza⁵⁶, Carl Magnus Brodén⁵⁷, Hjörtur Gislason⁵⁷, Kamran Shah⁵⁷, Antonio Ambrosi⁵⁸, Giovanna Pavone⁵⁸, Nicola Tartaglia⁵⁸, S Lakshmi Kumari Kona⁵⁹, Kalyan K⁵⁹, Cesar Ernesto Guevara Perez⁶⁰, Miguel Alberto Forero Botero⁶⁰, Adrian Covic⁶¹, Daniel Timofte⁶¹, Madalina Maxim⁶¹, Dashti Faraj⁶², Larissa Tseng⁶², Ronald Liem⁶², Gürdal Ören⁶², Evren Dilektasli⁶³, Ilker Yalcin⁶³, Hudhaifa AlMukhtar⁶⁴, Mohammed Al Hadad⁶⁴, Rasmi Mohan⁶⁴, Naresh Arora⁶⁵, Digvijaysingh Bedi⁶⁵, Claire Rives-Lange⁶⁶, Jean-Marc Chevallier⁶⁶, Tigran Poghosyan⁶⁶, Hugues Sebbag⁶⁷, Lamia Zinaï⁶⁷, Saadi Khaldi⁶⁷, Charles Mauchien⁶⁸, Davide Mazza⁶⁸, Georgiana Dinescu⁶⁸, Bernardo Rea⁶⁹, Fernando Pérez-Galaz⁶⁹, Luis Zavala⁷⁰, Anais Besa⁷¹, Anna Curell⁷¹, Jose M Balibrea⁷², Carlos Vaz⁷², Luis Galindo⁷², Nelson Silva⁷², José Luis Estrada Caballero⁷³, Sergio Ortiz Sebastian⁷³, João Caetano Dallegrave Marchesini⁷⁴, Ricardo Arcanjo da Fonseca Pereira⁷⁴, Wagner Herbert Sobottka⁷⁴, Felipe Eduardo Fiolo⁷⁵, Matias Turchi⁷⁵, Antonio Claudio Jamel Coelho⁷⁶, Andre Luis Zacaron⁷⁶, André Barbosa⁷⁷, Reynaldo Quinino⁷⁷, Gabriel Menaldi⁷⁸, Nicolás Paleari⁷⁸, Pedro Martinez-Duartez⁷⁸, Gabriel Martínez de Aragon Ramírez de Esparza⁷⁹, Valentin Sierra Esteban⁷⁹, Antonio Torres⁸⁰, Jose Luis Garcia-Galocha⁸⁰, MIguel Josa⁸⁰, Jose Manuel Pacheco-Garcia⁸¹, Maria Angeles Mayo-Ossorio⁸¹, Pradeep Chowbey⁸², Vandana Soni⁸², Hercio Azevedo de Vasconcelos Cunha⁸³, Michel Victor Castilho⁸³, Rafael Meneguzzi Alves Ferreira⁸³, Thiago Alvim Barreiro⁸³, Alexandros Charalabopoulos⁸⁴, Elias Sdralis⁸⁴, Spyridon Davakis⁸⁴, Benoit Bomans⁸⁵, Giovanni Dapri⁸⁵, Koenraad Van Belle⁸⁵, MazenTakieddine⁸⁶, Pol Vaneukem⁸⁶, Esma Seda Akalın Karaca⁸⁷, Fatih Can Karaca⁸⁷, Aziz Sumer⁸⁸, Caghan Peksen⁸⁸, Osman Anil Savas⁸⁸, Elias Chousleb⁸⁹, fahad Elmokayed⁹⁰, islam fakhereldin⁹⁰, Hany Mohamed Aboshanab⁹⁰, Talal swelium⁹⁰, Ahmad Gudal⁹¹, Lamees Gamloo⁹¹, Ayushka Ugale⁹², Surendra Ugale⁹², Clara Boeker⁹³, Christian Reetz⁹³, Ibrahim Ali Hakami⁹³, Julian Mall⁹³, Andreas Alexandrou⁹⁴, Efstratia Baili⁹⁴, Zsolt Bodnar⁹⁵, Almantas Maleckas⁹⁶, Rita Gudaityte⁹⁶, Cem Emir Guldogan⁹⁷, Emre Gundogdu⁹⁷, Mehmet Mahir Ozmen⁹⁸, Deepti Thakkar⁹⁹, Nandakishore Dukkipati⁹⁹, Poonam Shashank Shah¹⁰⁰, Shashank Subhashchandra Shah¹⁰⁰, Simran Shashank Shah¹⁰⁰, Md Tanveer Adil¹⁰¹, Periyathambi Jambulingam¹⁰¹, Ravikrishna Mamidanna¹⁰¹, Douglas Whitelaw¹⁰², Md Tanveer Adil¹⁰², Vigyan Jain¹⁰², Deepa Kizhakke Veetil¹⁰³, Randeep Wadhawan¹⁰³, Antonio Torres¹⁰⁴, Max Torres¹⁰⁴, Tabata Tinoco¹⁰⁴, Wouter Leclercq¹⁰⁵, Marleen Romeijn¹⁰⁵, Kelly van de Pas¹⁰⁵, Ali K. Alkhazraji¹⁰⁶, Safwan A. Taha¹⁰⁶, Murat Ustun¹⁰⁷, Taner Yigit¹⁰⁷, Aatif Inam¹⁰⁸, Muhammad Burhanulhaq¹⁰⁸, Abdolreza Pazouki¹⁰⁹, Foolad Eghbali¹⁰⁹, Mohammad Kermansaravi¹⁰⁹, Amir Hosein Davarpanah Jazi¹¹⁰, Mohsen Mahmoudieh¹¹⁰, Neda Mogharehabed¹¹⁰, Gregory Tsiotos¹¹¹, Konstantinos Stamou¹¹¹, Francisco J. Barrera Rodriguez¹¹², Marco A. Rojas Navarro¹¹², Omar MOhamed Torres¹¹², Sergio Lopez Martinez¹¹², Elda Rocio Maltos Tamez¹¹³, Gustavo A. Millan Cornejo¹¹³, Jose Eduardo Garcia Flores¹¹³, Diya Aldeen Mohammed¹¹⁴, Mohamad Hayssam Elfawal¹¹⁴, Asim Shabbir¹¹⁵, Kim Guowei¹¹⁵, Jimmy BY So¹¹⁵, Elif Tuğçe Kaplan¹¹⁶, Mehmet Kaplan¹¹⁶, Tuğba Kaplan¹¹⁶, DangTuan Pham¹¹⁷, Gurteshwar Rana¹¹⁷, Mojdeh Kappus¹¹⁷, Riddish Gadani¹¹⁸, Manish Kahitan¹¹⁸, Koshish Pokharel¹¹⁸, Alan Osborne¹¹⁹, Dimitri Pournaras¹¹⁹, James Hewes¹¹⁹, Errichetta Napolitano¹²⁰, Sonja Chiappetta¹²⁰, Vincenzo Bottino¹²⁰, evelyn dorado¹²¹, Axel Schoettler¹²², Daniel Gaertner¹²², Katharina Fedtke¹²², Francisco Aguilar-Espinosa¹²³, Saul Aceves-Lozano¹²³, Alessandro Balani¹²⁴, Carlo Nagliati¹²⁴, Damiano Pennisi¹²⁴, Andrea Rizzi¹²⁵, Francesco Frattini¹²⁵, Diego Foschi¹²⁶, Laura Benuzzi¹²⁶, CHIRAG PARIKH¹²⁷, HARSHIL SHAH¹²⁷, Enrico Pinotti¹²⁸, Mauro Montuori¹²⁸, Vincenzo Borrelli¹²⁸, Jerome Dargent¹²⁹, Catalin A COPAESCU¹³⁰, Ionut HUTOPILA¹³⁰, Bogdan SMEU¹³⁰, Bart Witteman¹³¹, Eric Hazebroek¹³¹, Laura Deden¹³¹, Laura Heusschen¹³¹, Sietske Okkema¹³¹, Theo Aufenacker¹³¹, Willem den Hengst¹³¹, Wouter Vening¹³¹, Yonta van der Burgh¹³¹, Ahmad Ghazal¹³², Hamza Ibrahim¹³², Mourad Niazi¹³², Bilal Alkhaffaf¹³³, Mohammad Altarawni¹³³, Giovanni Carlo Cesana¹³⁴, Marco Anselmino¹³⁴, Matteo Uccelli¹³⁴, Stefano Olmi¹³⁴, Christine Stier¹³⁵, Tahsin Akmanlar¹³⁵, Thomas Sonnenberg¹³⁶, Uwe Schieferbein¹³⁶, Alejandro Marcolini¹³⁷, Diego Awruch¹³⁷, Marco Vicentin¹³⁷, Eduardo Lemos de Souza Bastos¹³⁸, Samuel Azenha Gregorio¹³⁸, Anmol ahuja¹³⁹, Tarun mittal¹³⁹, Roel Bolckmans¹⁴⁰, Tom Wiggins¹⁴⁰, Clément Baratte¹⁴¹, Judith Aron-Wisnewsky¹⁴¹, Laurent Genser¹⁴¹, Lynn Chong¹⁴², Lillian Taylor¹⁴², Salena Ward¹⁴², Lynn Chong¹⁴³, Lillian Taylor¹⁴³, Michael W Hi¹⁴³, Helen Heneghan¹⁴⁴, Naomi Fearon¹⁴⁴, Andreas Plamper¹⁴⁵, Karl Rheinwalt¹⁴⁵, Helen Heneghan¹⁴⁶, Justin Geoghegan¹⁴⁶, Kin Cheung Ng¹⁴⁶, Naomi Fearon¹⁴⁶, Krzysztof Kaseja¹⁴⁷, Maciej Kotowski¹⁴⁷, Tarig A Samarkandy¹⁴⁸, Adolfo Leyva-Alvizo¹⁴⁹, Lourdes Corzo-Culebro¹⁴⁹, Cunchuan Wang¹⁵⁰, Wah Yang¹⁵⁰, Zhiyong Dong¹⁵⁰, Manel Riera¹⁵¹, Rajesh Jain¹⁵¹, Hosam Hamed¹⁵¹, Mohammed Said¹⁵¹, Katia Zarzar¹⁵², Manuel Garcia¹⁵², Ahmet Gökhan Türkçapar¹⁵³, Ozan Şen¹⁵³, Edoardo Baldini¹⁵⁴, Luigi Conti¹⁵⁴, Cacio Wietzycoski¹⁵⁵, Eduardo Lopes¹⁵⁵, Tadeja Pintar¹⁵⁶, Jure Salobir¹⁵⁶, Cengiz Aydin¹⁵⁷, Semra Demirli Atici¹⁵⁷, Anıl Ergin¹⁵⁸, Huseyin Ciyiltepe¹⁵⁸, Mehmet Abdussamet Bozkurt¹⁵⁹, Mehmet Celal Kizilkaya¹⁵⁹, Nezihe Berrin Dodur Onalan¹⁵⁹, Mariana Nabila Binti Ahmad Zuber¹⁶⁰, Wei Jin Wong¹⁶⁰, Amador Garcia¹⁶¹, Laura Vidal¹⁶¹, Marc Beisani¹⁶¹, Jorge Pasquier¹⁶², Ramon Vilallonga¹⁶², Sharad Sharma¹⁶³, Chetan Parmar¹⁶⁴, Lyndcie Lee¹⁶⁴, Pratik Sufi¹⁶⁴, Hüseyin Sinan¹⁶⁵, Mehmet Saydam¹⁶⁵

¹2'nd Department of General Surgery, Jagiellonian University Medical College, Krakow, Poland, ²4^th Surgical Department, Evaggelismos General Hospital of Athens, Athens, Greece, ³A Z Sint Elisabeth Zottegem, Belgium, ⁴ABC Medical Center Santa Fe, Mexico City, Mexico, ⁵Advanced Biomedical Sciences Department - Naples “Federico II” University - Italy, ⁶Advanced Medicine Institute. Reynosa, MEXICO., ⁷AIG hospital, Hyderabad, India, ⁸Ain Shams University Hospitals, Cairo, Egypt, ⁹Al shark hospital fujairah UAE, ¹⁰American Medical Clinic, Saint Petersburg, Russia, ¹¹Amin University Hospital, Isfahan, Iran, ¹²Apoorv Hi Tech at Gokuldas Hospital, ¹³Asian Bariatrics, Ahmedabad, India, ¹⁴Assuta Medical Center, Tel Aviv, Israel, ¹⁵Atasam Hospitals,Samsun, Turkey, ¹⁶AZBariatrics Obesity Center, Istanbul, ¹⁷Bariatric and Metabolic surgery UnitOspedale A.Cardarelli Napoli Italia, ¹⁸Bariatric Surgery Department, Faculty of Medicine, Ain Shams University, Cairo, Egypt, ¹⁹Bariatric Surgery Experts, Monterrey, Mexico, ²⁰BAROS - Bariatric and Metabolic Surgery, Salvador, Brazil, ²¹BMI Alexandra Hospital, Manchester, UK, ²²Burjeel Hospital, Abu Dhabi, UAE, ²³Cairo University, Cairo, Egypt, ²⁴Center of Metabolic Surgery, Wockhardt Hospital, Agripada, Mumbai, India, ²⁴Center of Nutrition and Obesity, ABC Medical Center (Observatorio), Mexico City, ²⁵Centre Hospitalier Regional d'ORLEANS, ²⁶Centro de Obesidade do Instituto do Aparelho Digestivo, Porto Alegre, Brazil, ²⁷Centro Hospitalar e Universitario de Coimbra, Coimbra, Portugal, ²⁸Centro Médico de Asturias. Oviedo. Spain, ²⁹Centro Multidisciplinar da Doença Metabólica, Clínica Santo Antonio - Lusiadas, Amadora, Portugal, ³⁰Chaim Sheba Medical Center, Affiliated with Sackler School of Medicine, Tel Aviv University, Ramat Gan, Israel, ³¹Christus Muguerza Sur, Monterrey, Mexico, ³²CHU Félix Guyon, la Réunion, France, ³³Città di Castello Hospital, Usl Umbria 1, Città di Castello - Italy, ³⁴Clinic for Metabolic Surgery, Krankenhaus Nordwest, Frankfurt, Germany, ³⁵Clínica Santa Sofía, Caracas, Venezuela, ³⁶Clinica Universidad de Navarra. Pamplona. Spain, ³⁷Clinical Hospital Centre Osijek, Osijek, Croatia, ³⁸Clinique des Cedres, Cornebarrieu, France, ³⁹COMS, Apollo Spectra Hospital, New Delhi, India, ⁴⁰Danat Al Emarat Hospital, Abu Dhabi, UAE, ⁴¹Defeat Obesity Bariatric and Metabolic Surgery, CHRISTUS MUGUERZA Hospital Reynosa, Reynosa, Tamaulipas., ⁴²Delta CHIREC hospital, Brussels Belgium, ⁴³Department of General Surgery, Center Hospitalier Intercommunal de Créteil, Paris, France, ⁴⁴Department of General Surgery, Gazi University Faculty of Medicine, Turkey, ⁴⁵Department of General Surgery, Military Institute of Medicine, Szaserów 128, 04-141, Warsaw, Poland, ⁴⁶Department of Public Health, “Federico II” University of Naples, Naples, Italy, ⁴⁷Division of General Surgery & Bariatric Center of Excellence IFSO-EC, University La Sapienza of Rome, Italy, ⁴⁸Doncaster and Bassetlaw Teaching Hospitals, ⁴⁹Dr. Lorenzo, Innovación Cirugía Obesidad y Diabetes, ⁵⁰East-Midlands Bariatric & Metabolic Institute (EMBMI), Royal Derby Hospital, Derby, UK, ⁵¹Elsafa Private Hospital & Mansoura University Hospital & Eldelta Hospital, ⁵²New York Minimally Invasive Surgery PLLC, New York, NY , USA, ⁵³First Department of Propaedeutic Surgery, Hippocration General Athens Hospital, National and Kapodistrian University of Athens, Athens, Greece, ⁵⁴Fırat University Hospital, Elazığ. Turkey, ⁵⁵Gastrointestinal, Bariatric & Metabolic Center at Jordan Hospital, Amman, Jordan, ⁵⁶GASTROMED-Zilberstein Institute, Sao Paulo, Brazil, ⁵⁷GB Obesitas Skaane, Malmö. Sweden., ⁵⁸General Surgery, University of Foggia. Italy., ⁵⁹Glenagles Global Hospital, Lakdikapul, Hyderabad, ⁶⁰Grammo SAS IPS, Bogotá, Colombia, ⁶¹Grigore T. Popa University of Medicine and Pharmacy, Iasi, Romania, ⁶²Groene Hart Hospital in Gouda & Dutch Obesity Clinic The Hague, Netherlands, ⁶²Gürdal Ören Bariatric Surgery Center, İstanbul, Turkey, ⁶³Hayat Hospital, General Surgery, Bariatric & Metabolic Surgery , Bursa , Turkey, ⁶⁴Healthpoint Hospital, Abu Dhabi, UAE, ⁶⁵HOPE OBESITY CENTRE, AHMEDABAD, INDIA, ⁶⁶Hôpital Européen Georges Pompidou, AP-HP, Université de Paris, Paris, France, ⁶⁷Hôpital Privé de Provence (HPP), Aix-en-Provence, France, ⁶⁸Hôpital Ste Musse Centre Hospitalier Toulon, ⁶⁹Hospital Ángeles Lomas, Estado de México, México, ⁷⁰Hospital Christus Muguerza Sur - Monterrey México, ⁷¹Hospital Clínic de Barcelona, Barcelona, Spain, ⁷²Hospital Clínic de Barcelona, Barcelona, Spain, ⁷²Hospital CUF Tejo, Lisbon, Portugal, ⁷³Hospital General Universitario Alicante Spain, ⁷⁴Hospital Marcelino Champagnat, Curitiba, Brazil, ⁷⁵Hospital Privado de Comunidad - Mar del Plata - Argentina, ⁷⁶Hospital Rios D'Or , Rio de Janeiro, Brazil, ⁷⁷Hospital Unimed Natal, Natal, Brazil, ⁷⁸Hospital Universitario Austral, Bariatric and Metabolic department. Buenos Aires Argentina, ⁷⁹Hospital Universitario de Álava, Vitoria- Gasteiz. Spain, ⁸⁰Hospital Universitario Madrid Monteprincipe. Hospital Clinico San Carlos. Madrid, ⁸¹Hospital Universitario Puerta del Mar. Cadiz. Spain, ⁸²Institute of Minimal Access, Metabolic & Bariatric Surgery, Max Super-Speciality Hospital, Saket, New Delhi, India, ⁸³Instituto Campineiro de Tratamento da Obesidade, Campinas, Brazil, ⁸⁴Interbalcan Medical Center, ⁸⁵International School Reduced Scar Laparoscopy, Brussels, Belgium, ⁸⁶Isppc chu -André Vésale , metabolic & Bariatric surgery, ⁸⁷İstanbul Bilgi University,Turkey,(first author), Department of Pulmonary Medicine, Istanbul Yedikule Chest Diseases and Thoracic Surgery Education and Research Hospital, Zeytinburnu, Turkey(for sekond author), ⁸⁸Istinye University, School of Medicine, Istanbul,Turkey, ⁸⁹Jackson North Medical Center, Miami Fl, ⁹⁰king Abdul aziz hospital, Alhasa,saudi arabia, ⁹¹King Abdullah Medical Complex, Jeddah, KSA, ⁹²Kirloskar Hospital, Hyderabad, India, ⁹³Klinikum Region Hannover- Klinikum Nordstadt, ⁹⁴Laiko General Hospital, National and Kapodistrian University of Athens, Greece, ⁹⁵Letterkenny University Hospital, Letterkenny, Ireland, ⁹⁶Lithuanian University of Health Sciences, Surgery Department, Kaunas, Lithuania, ⁹⁷Liv Hospital Ankara, Turkey, ⁹⁸Liv Hospital Ankara, Turkey (Istinye University School of Medicine), ⁹⁹Livlife Hospitals, Hyderabad, India, ¹⁰⁰LOC Healthcare LLP, Pune, India, ¹⁰¹Luton and Dunstable Hospital, ¹⁰²Luton and Dunstable University Hospital, ¹⁰³Manipal Hospital, New Delhi, India, ¹⁰⁴Max Medical, centro de cirugía bariátrica/robótica, Hospital Metropilitano de Quito/Ecuador, ¹⁰⁵Máxima Medical Center, Veldhoven, The Netherlands, ¹⁰⁶Mediclinic Hospital Airport Road, Abu Dhabi, UAE., ¹⁰⁷Memorial Hospital, Istanbul, Turkey, ¹⁰⁸Metabolic, Thoracic & General Surgery Team III, Department of General Surgery , Pakistan Institute of Medical Sciences (PIMS), Islamabad, Pakistan., ¹⁰⁹Minimally Invasive Surgery Research Center, Division of Minimally invasive and Bariatric surgery, Department of Surgery, Rasool-e Akram Hospital, Iran University of Medical Sciences, Tehran, Iran, ¹¹⁰Minimally Invasive Surgery Research Center, Isfahan University of Medical Sciences, Isfahan, Iran, ¹¹¹MITERA Hospital, Athens, Greece, ¹¹²Monterrey Gastro & Bariatric Group, Monterrey Mexico, ¹¹³MtyBariatrics, Monterrey, Nuevo Leon, Mexico, ¹¹⁴Najjar Hospital,Beirut, Lebanon, ¹¹⁵National University Hospital Singapore, ¹¹⁶NCR International Hospital, Gaziantep, Turkey, ¹¹⁷Niagara Falls Memorial Medical Center, Niagara Falls, NY, USA, ¹¹⁸NOBESITY BARIATRIC CENTRE, K D HOSPITAL, AHMEDABAD, INDIA, ¹¹⁹North Bristol NHS Trust, ¹²⁰Obesity and Metabolic Surgery Unit, Ospedale Evangelico Betania, Naples, Italy, ¹²¹Obesity and stethic surgery clinic clinica med cali colombia, ¹²²Obesity Center, Municipal Hospital Karlsruhe, Germany, ¹²³Obesity Clinic:Los Altos Obesity Surgery, Tepatitlan, Mexico, ¹²⁴Ospedale di Gorizia, Italy. Struttura Complessa Chirurgia Generale, ¹²⁵Ospedale Galmarini Tradate, Varese, Italy, ¹²⁶Ospedale San Giuseppe IRCCS Multimedica, University of Milan, Milan, Italy, ¹²⁷Parul Institute of Medical Sciences & Research, Parul Uiversity, Waghodia, Vadodara, India, ¹²⁸Policlinico San Pietro, Bergamo, Italy, Unitá di Chirurgia Bariatrica, ¹²⁹Polyclinique Lyon-Nord, 69140 Rillieux, France, ¹³⁰Ponderas Academic Hospital, Bucharest, Romania, ¹³¹Rijnstate Hospital/Vitalys Clinics, Arnhem, the Netherlands, ¹³²Saint Louis Hospital - Aleppo,Syria, ¹³³Salford Royal NHS Foundation Trust, ¹³⁴San Marco Hospital GSD, Zingonia (BG), Italy, ¹³⁵Sana Obesity Center Northrhine Westphalia, Clinic for General, Visceral, and Transplantation Surgery, RWTH University Aachen., ¹³⁶Sana Obesity Center Northrhine Westphalia, ¹³⁷Sanatorio Britanico de Rosario, Rosario, Santa Fe, Argentina, ¹³⁸Santa Casa de Marilia, Marilia, Brazil, ¹³⁹sir ganga ram hospital delhi india, ¹⁴⁰Somerset NHS Foundation Trust, ¹⁴¹Sorbonne Université, Institute of Cardiometabolism and Nutrition ICAN, Assistance Publique-Hôpitaux de Paris, Departments of Digestive surgery and Nutrition, Pitié-Salpêtrière University Hospital, Paris, France., ¹⁴²St Vincent's Hospital Melbourne, ¹⁴³St Vincent's Hospital, Melbourne, Australia, ¹⁴⁴St Vincent's University Hospital, Dublin, Ireland, ¹⁴⁵St. Franziskus Hospital, Cologne, Germany, ¹⁴⁶St. Vincent's University Hospital, Dublin, Ireland, ¹⁴⁷State Clinical Hospital No 2 of the Pomeranian Medical University in Szczecin, Poland, ¹⁴⁸Sutter Gould Medical Foundation, Dameron Hospital - Ca, USA, ¹⁴⁹Tecnologico de Monterrey, Monterrey, MX, ¹⁵⁰The First Affiliated Hospital of Jinan University, Guangzhou, China, ¹⁵¹The Shrewsbury and Telford Hospital, Shrewsbury, UK, ¹⁵¹Truelife bariatric and digestive surgery center, Mansoura, Dakahleyya, Egypt, ¹⁵²Tu Opcion Bariatrica, ¹⁵³Türkçapar Bariatrics Obesity Center, İstanbul, Turkey, ¹⁵⁴U.O. Chirurgia, Ospedale “Guglielmo da Saliceto”, Piacenza, Italy, ¹⁵⁵Unimed Vale do Caí Hospital, Montenegro, BR. Maicé Hospital, Caçador, BR, ¹⁵⁶University Medical Center Ljubljana, Slovenia, ¹⁵⁷University of Health Sciences Tepecik Training and Research Hospital, Department of General Surgery, Izmir, Turkey, ¹⁵⁸University of Health Sciences, Fatih Sultan Mehmet Training and Research Hospital, General Surgery Department, Istanbul, Turkey, ¹⁵⁹University of Health Sciences, Kanuni Sultan Süleyman Training and Research Hospital, Istanbul, Turkey, ¹⁶⁰University of Malaya Medical Centre, Kuala Lumpur, Malaysia, ¹⁶¹Vall d'Hebron University Hospital, Barcelona, Spain, ¹⁶²Vall Hebron Hospital Campus - Hospital de Barcelonoa-SCIAS, ¹⁶³Vinamra Swaraj Hospital, Navi Mumbai, India, ¹⁶⁴Whittington Health NHS Trust, London, United Kingdom, ¹⁶⁵www.metabolistsurgery.com Istanbul Turkey

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