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Bariatric experts issue recommendations for procedure selection in class I and II obesity patients

Seventy-eight experienced bariatric surgeons from 32 countries, who participated in a two-round Modified Delphi consensus voting process, have issued their recommendations for procedure selection in class I and II obesity patients.



The most recent American Society of Metabolic and Bariatric Surgery (ASMBS) and the International Federation for the Surgery of Obesity and Metabolic Disorders (IFSO) guidelines suggest that metabolic and bariatric surgery (MBS) should be strongly recommended for patients with Class II obesity (BMI of 35–39.9 kg/m2) or higher, regardless of the presence or absence of obesity-related comorbidities. Additionally, MBS should be considered as a treatment option for individuals with Class I obesity (BMI of 30–34.9 kg/m2) who have obesity-related comorbidities.

In addition, the guidelines recommended modifying the BMI thresholds for the Asian population, wherein a BMI greater than 25 kg/m2 indicates clinical obesity and individuals with a BMI exceeding 27.5 kg/m2 should be provided with MBS as an option.


However, there are still numerous issues regarding the selection of the appropriate type of MBS, as well as technical details of the operation, for these groups of patients. Therefore, Delphi exercise was designed to develop the first consensus guidelines for procedure selection in Class I and II obesity to provide clinicians with a useful tool for their daily clinical practice. Overall, there was largely a consensus amongst the experts with at least 70% agreement on 54 of 64 final statements.


The majority of experts concurred that MBS can be considered as a treatment option for patients below 18 years of age who have Class II obesity, irrespective of the presence, severity, or absence of symptoms, especially after conservative treatment options such as new anti-obesity medications (AOMs) have failed. However, there was no consensus among experts regarding the use of MBS for patients below 18 years of age who have Class I obesity and fail to achieve substantial or long-lasting weight loss or obesity-associated medical problems improvement using non-surgical methods.


There was a consensus on the use of intra-gastric balloon (IGB) as a treatment option for patients with Class I obesity, irrespective of the presence, absence, or severity of obesity-associated medical problems, particularly when conservative treatment options including new AOMs have failed, and the patient is unwilling to undergo MBS. However, there was no consensus on the use of IGB as a treatment option for patients with Class II obesity or patients with T2DM and a BMI≥30 kg/m2, in case of failure of conservative treatment.


The majority of participants expressed the view that endoscopic sleeve gastroplasty (ESG) can be considered as a treatment option for patients with Class I and II obesity, as well as patients with T2DM and a BMI of ≥ 30 kg/m2, regardless of the presence, absence, or severity of obesity-associated medical problems, particularly when conservative treatment options, including new AOMs, have failed, and the patient is unwilling to undergo MBS.


There was disagreement consensus on adjustable gastric banding (AGB) as a treatment option for patients with Class I and II obesity, as well as patients with T2DM and a BMI of ≥ 30 kg/m2.


There was a consensus agreement on sleeve gastrectomy (SG) and Roux-en-Y gastric bypass (RYGB) as viable treatment options for these three groups of patients. However, there was no consensus on the suitability of Biliopancreatic Diversion- Duodenal Switch (BPD-DS), Ileal Interposition and bipartition procedures as treatment options for these groups of patients.

One anastomosis gastric bypass (OAGB) is a suitable treatment option for patients with Class II obesity, the experts agreed, irrespective of the presence, absence or severity of obesity-associated medical problems, as well as for patients with T2DM and a BMI≥30kg/m2. However, there was no consensus among experts regarding the use of OAGB for patients with Class I obesity who fail to achieve substantial or long-lasting weight loss or comorbidity improvement using non-surgical methods.


The experts disagreed about the use of larger bougies (40Fr and above) for SG in patients with Class I and II obesity as well as patients with T2DM and a BMI30kg/m2. A majority of experts agreed that the starting point for antral resection during SG should not vary for patients with a BMI30–40kg/m2 compared to those with a BMI≥40kg/m2. They concluded that antral resection should be initiated at a distance of at least 4cm from the pylorus, regardless of the presence, absence or severity of comorbidities.


The experts also disagreed on whether to create a longer pouch or a gastro-jejunal anastomosis exceeding 3cm in patients with Class I and II obesity or patients with T2DM and a BMI≥30kg/m2, as compared to patients with higher BMI (BMI≥40kg/m2). However, was no consensus on the optimal length of the Biliopancreatic Limb (BPL) of RYGB for patients with a BMI30–40kg/m2 compared to those with a BMI≥40kg/m2.


A majority of experts believed that the BPL of OAGB should not exceed 150cm for patients with Class I obesity. However, there was no consensus on the optimal length of the BPL of OAGB for patients with Class II obesity or patients with T2DM and Class I obesity. The experts could not agree on the creation of a gastro-jejunal anastomosis exceeding 4cm during OAGB for patients with Class I and II obesity or patients with T2DM and a BMI≥30kg/m2, as compared to patients with higher BMI (BMI≥40kg/m2).


“The use of the standard primary bariatric endoscopic (IGB, ESG) and surgical procedures (SG, RYGB, OAGB) is also accepted in Class I and II Obesity since statements reached consensus regarding these current procedures,” the authors concluded. “Nevertheless, randomised controlled trials in this patient’s class are still necessary to give our patients with Class I and II Obesity the best treatment approach in the future.”


The findings were featured in the paper, ‘Current recommendations for procedure selection in class I and II obesity developed by an expert modified Delphi consensus’, published in Scientific Reports. To access the statement, please click here

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