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IFSO Consensus on definitions and clinical practice guidelines (part 5)

In the final part of our report from Hamburg, topics under discussion included weight recurrence after surgery, NASH and MBS, CVD and MBS, Nephropathy and surgery, and adolescent MBS and more. The following are the brief highlights from the presentations.

Weight/metabolic disease recurrence after surgery

Dr Pierre Garneau (Hôpital du SacréCoeur de Montréal/University of Montréal, Canada), who assessed the options following weight/metabolic disease recurrence after surgery, said that there are currently no standard definition for clinically significant recurrent weight gain (RWG) after MBS and no common set of treatment guidelines for RWG has been agreed (Majid et al. Current state of the definition and terminology related to weight recurrence after metabolic surgery: review by the POWER Task Force of the American Society for Metabolic and Bariatric Surgery. Surg Obes Relat Dis. 2022 Jul;18(7):957-963, level 3). RWG can occur after primary MBS with an estimated incidence of 9%–91% depending on the definition. However, the increase in BMI or being above a certain BMI has not been clearly correlated with the recurrence of comorbidities and the ability to correlate its impact with clinical outcomes such as recurrence of co-morbidities is limited.

The American Society for Metabolic and Bariatric Surgery Revision Task Force reported in 2014 (Brethauer et al Systematic review on reoperative bariatric surgery: American Society for Metabolic and Bariatric Surgery Revision Task Force. Surg Obes Relat Dis. 2014 SepOct;10(5):952-72, level 3) that re-operative MBS demonstrates improved weight loss and co-morbidity reduction after reintervention, and complication rates are generally higher after revision surgery, compared to primary surgery. However, outcomes of re-operative bariatric surgery are inconsistently reported in the literature. Multi-disciplinary team evaluation should be done before any redo-procedures and if morbid obesity or obesity-related disease is still present after primary therapy, additional therapy is indicated. The specific type of re-operative procedure performed should be based on the primary operation, the patient’s anatomy, the patient’s weight and co-morbidities, and the experience of the surgeon.

After failed LAGB, there are multiple options including conversion to SG, RYGB, OAGB and BPD/DS or SADI-S (levels 3 and 4). After failed vertical banded gastroplasty (VBG) conversion to RYGB or BPD/DS or sleeve (high complication rate, level 4 and 5) (Kermansaravi et al. Best practice approach for redo-surgeries after sleeve gastrectomy, an expert’s modified Delphi consensus. Surg Endosc. 2023 Mar;37(3):1617-1628). After a failed sleeve, there is the option to convert to RYGB, OAGB or SADI-S (levels 3 and 4), and after failed SADI a conversion to BPD/DS (level 4) (Brethauer et al Systematic review on reoperative bariatric surgery: American Society for Metabolic and Bariatric Surgery Revision Task Force. Surg Obes Relat Dis. 2014 Sep-Oct;10(5):952-72). The first consensus statement on revisional bariatric surgery by Mahawar et al (The first consensus statement on revisional bariatric surgery using a modified Delphi approach. Surg Endosc. 2020 Apr;34(4):1648-1657) reported that lengthening of the bilio-pancreatic limb was the only consensus option after RYGB (94.3%) and OAGB (72.8%).

Metabolically challenged patients – High BMI

Dr Almino Ramos (Gastro-Obeso-Center - Institute for Metabolic Optimization, Sao Paulo, Brazil) said there was limited evidence (2 RCTs, 2 Systematic reviews and 19 retrospective cohorts) reporting on metabolically challenged patients with BMI>50 kg/m2 including severe comorbid conditions such as type 2 diabetes mellitus, NASH syndrome, nephritis and heart failure. Most studies in BMS have been focused on mild to severe obesity (BMI<50 kg/m2 ) - Obesity Grade II and III, and good quality clinical data involving patients in extreme obesity conditions with BMI≥50 kg/m2 is more scarce.

High BMI patients with BMI≥50 kg/ m2 (formerly super obesity, super-superobesity) now considered as obesity grade IV and V in some studies have an advanced stage of obesity with a large amount of fat, presenting more severe associated diseases. He added this group of patients is one of the most challenging groups to treat in BMS. Therefore, interventions may be challenging in patients with BMI≥50 kg/m2 with higher risks and less responsiveness to the treatment. The growth rate of BMI≥50 kg/ m2 is rising more rapidly (USA) compared to the prevalence of BMI categories <50 kg/m2. Analysis of different causes of hospitalisation data for patients with BMI> 50 Kg/m2 will involve more ICU necessity, more mechanical ventilation requirements and longer lengths of stay in hospitals, but not a higher mortality risk. This group will include more female patients and left ventricle hypertrophy but not hypertension or T2DM, and the rate of complications related to the hospital stay will be higher.

A survey of 789 bariatric surgeons in 2022 (Kermansaravi et al. The first survey addressing patients with BMI over 50: a survey of 789 bariatric surgeons. Surg Endosc. 2022 Aug;36(8):6170-6180) found most surgeons (89.9%) believed that metabolic/bariatric surgery on patients with BMI>50 kg/m2 should only be performed by expert bariatric surgeons.

“This is important because individuals with BMI≥50 kg/m2 are more likely to have more complex health issues such as diabetes, hypertension, congestive heart failure and chronic obstructive pulmonary disease resulting in more complex and risky procedures. Having the surgery by experts in a center of excellence will be fundamental” he added.

Moreover, Ramos said it is universally accepted that bariatric surgery in patients with BMI≥50 kg/m2 results in less weight loss and more complications when compared to patients with BMIs less than 50 kg/m2 . The literature indicates that there is a preference for sleeve gastrectomy with some studies considering it as a one-stage procedure and others as a staged strategy procedure based in the insufficient weight loss of the primary procedure. However, studies consistently show an association between increasing BMI and lower odds of successful weight loss and a higher risk of morbidity and mortality after surgery.

Five-year surgical outcomes in BMI≥50 kg/m2 patients consistently demonstrate good weight loss, with SG resulting in a BMI decrease of 10-12 kg/m2 (TWL 25-27%), RYGB 14-15 kg/m2 (TWL 28- 30%), DS 20-24 kg/m2 (TWL 36-38%) with SADI-S having similar results to DS (10% less) and OAGB in increasing adoption in this group of patients, however, he noted that there is no consensus whether longer limbs result in better weight loss in patients with BMIs over 50 kg/m2 . He added that there is a preference for staged procedure with half of the surgeons believing that a 2-stage approach should be offered to patients with BMI>50 kg/ m2 , with SG being the first step. Robotic surgery for patients with severe obesity does offer ergonomic advantages for surgeons, but without any documented clinical advantages to the patients when compared to laparoscopic approaches.

He concluded that mortality rates for the high BMI group were numerically higher across all time periods, and the increased risk in the first year reached statistical significance. For follow-up over five years, one RCT provided low-strength evidence that, compared to LRYGB, DS achieves better weight control and has comparable diabetes remission and mortality but a higher risk of hospital readmissions and necessity of reoperations related to the initial procedure. In this group of patients, ICU is not mandatory, however, there is a higher unplanned ICU admission rate among these subjects and prevention protocol for rhabdomyolysis and DVT/PTE should be especially concerning in this group, he concluded.

NASH and Metabolic/Bariatric Surgery

Professor Francois Pattou (University Hospital, Lille, France) began his presentation by stating nonalcoholic steatohepatitis (NASH) is the form of nonalcoholic fatty liver disease (NAFLD) in which you have inflammation of the liver and liver damage, the inflammation and liver damage of NASH can cause fibrosis of the liver, leading to cirrhosis. However, there are limited levels of evidence to ascertain whether surgery helps to treat (NASH) (level 2) and a limited number of papers on the common (rare) harms of surgery in NASH (level 2 (3)).

The efficacy of surgery has been reported in a prospective cohort study by Lassailly et al. (Bariatric Surgery Provides Long-term Resolution of Nonalcoholic Steatohepatitis and Regression of Fibrosis. Gastroenterology. 2020 Oct;159(4):1290- 1301.e5) who reported that resolution of NASH was observed at one year after bariatric surgery in biopsies from 84% of patients, with no significant recurrence between one and five years (p=0.17). Fibrosis began to decrease by one year after surgery and continued to decrease until five years (p<0.001).

The safety surgery on this group of patients was outlined by a meta-analysis by Bhangui et al. (Assessment of risk for non-hepatic surgery in cirrhotic patients. J Hepatol. 2012 Oct;57(4):874-84) found the perioperative morbidity and mortality following non-hepatic surgical procedures in patients with cirrhosis are significant, with mortality rates of up to 50% reported following surgery in patients with decompensated CLD. They noted that three factors essentially determine the extent of surgical risk; degree of decompensation (higher MELD and CTP score), whether the surgery is performed as an emergency procedure or electively, and the nature/type of surgery.

However, a study by Aminian et al. (Association of Bariatric Surgery With Major Adverse Liver and Cardiovascular Outcomes in Patients With Biopsy-Proven Nonalcoholic Steatohepatitis. JAMA. 2021 Nov 23;326(20):2031-2042) that investigated the long-term relationship between MBS and incident major adverse liver outcomes and MACE in patients with obesity and biopsy-proven fibrotic NASH without cirrhosis, reported bariatric surgery vs. nonsurgical management was associated with a significantly lower risk of incident major adverse liver outcomes (2.3% vs. 12.9%) and MACE (8.5% vs. 15.7%) at ten years.

More recently, the outcomes from the BRAVES RCT (Verrastro et al. Bariatric-metabolic surgery versus lifestyle intervention plus best medical care in non-alcoholic steatohepatitis (BRAVES): a multicentre, open-label, randomised trial. Lancet. 2023 Apr 20:S0140- 6736(23)00634-7) found that bariatric and metabolic surgery is more effective than lifestyle interventions and optimised medical therapy in the treatment of NASH with the probability of NASH resolution 3.60 times greater (p<0·0001) in the RYGB group and 3.67 times greater (p<0·0001) in the SG group vs. the lifestyle modification group.

He concluded that future recommendation(s) regarding MBS for NASH may come from four ongoing RCTs, BariaNash (BS for NASH With Advanced Liver Fibrosis, France), VSG and Lifestyle Modification for the Treatment of NASH, USA), BeLEANeR (BS vs. Lifestyle Modification for NASH, Brazil) and NASH-APOLLO (Endoscopic Gastric Tubulization in Patients With NASH, Spain).

CVD and metabolic/bariatric surgery (MBS)

Dr Dror Dicker (Sackler School of Medicine Tel Aviv University, Israel) said that weight is a risk factor for cardiovascular disease (CVD) and according to a population-based cohort study of 3·6 million adults in the UK, there is a 29% increased CVD risk for every five units above a BMI of 25 kg/m2 (Bhaskaran K, Lancet Diabetes Endocrinol 2018; 6: 944–53).

Clearly, decreasing weight also reduces the CVD risk, as reported by Haase, et al. (Weight loss and risk reduction of obesity-related outcomes in 0.5 million people: evidence from a UK primary care database. Int J Obes 45, 1249–1258 (2021)) who noted that the greatest benefits observed for the established CVD risk factors T2D, hypertension and dyslipidaemia.

A systematic review and meta-analysis by van Veldhuisen et al. (Bariatric surgery and cardiovascular disease: a systematic review and meta-analysis. Eur Heart J. 2022 May 21;43(20):1955-1969), suggested that MBS was associated with reduced allcause and CV mortality ((HR 0.59, 95% CI 0.47–0.73, p=0.001, I2=71%), and lowered incidence of several CV diseases in patients with obesity.

The effectiveness of MBS on mortality is associated with a patient’s diabetes background. As reported by Dicker et al. (All-Cause Mortality of Patients With and Without Diabetes Following Bariatric Surgery: Comparison to Nonsurgical Matched Patients. Obes Surg. 2021 Feb;31(2):755-762), who found a survival advantage of MBS after a median follow-up of 4.2 years was greater among individuals with than without diabetes for the three types of surgery performed, suggesting priority considerations for MBS candidates.

Furthermore, a 20-year follow-up study by Pontiroli et al. (A 23- year study of mortality and development of co-morbidities in patients with obesity undergoing bariatric surgery (laparoscopic gastric banding) in comparison with medical treatment of obesity. Cardiovasc Diabetol. 2018 Dec 29;17(1):161) found that compared to controls, LAGB was associated with reduced mortality (p=0.003), a lower incidence of diabetes (15 vs 75 cases, p=0.001), of CV diseases (61 vs 226 cases, p=0.009), of cancer (10 vs 35, p=0.01), and of renal diseases (0 vs 35, p=0.001), and of hospital admissions (92 vs 377, p=0.001).

Finally, Dicker reported that GLP-1 receptor agonists, regardless of structural homology, reduced the risk of individual MACE components, all-cause mortality, hospital admission for heart failure, and worsening kidney function in patients with type 2 diabetes (Sattar et al Cardiovascular, mortality, and kidney outcomes with GLP-1 receptor agonists in patients with type 2 diabetes: a systematic review and meta-analysis of randomised trials. Lancet Diabetes Endocrinol. 2021 Oct;9(10):653-662). GLP-1 receptor agonists reduce MACE in patients with type 2 diabetes by 14% (HR 0·86 [95% CI 0·80-0·93]; p<0·0001) and all-cause mortality by 12% (HR 0·88 [95% CI 0·82-0·94]; p=0·0001). Dicker concluded that BMS leads to a 35%-50% reduction in total mortality, 31% in CV mortality and a 25%-58% reduction in CV events. Longer follow-up time is needed in order to better understand the BMS effects on morbidity and mortality.

Nephropathy and surgery

Dr Ricardo Cohen (Oswaldo Cruz German Hospital, Sao Paulo, Brazil) discussed the role of metabolic surgery on kidney outcomes. He said that Afkarian et al. (J Am Soc Nephrol. 2013 Feb;24(2):302-8), found those with kidney disease predominantly account for the increased mortality observed in type 2 diabetes. Those with type 2 diabetes but without albuminuria and decreased glomerular filtration have 10-year cumulative mortality rates of 4.1%, while the individuals with diabetes and albuminuria and decreased glomerular filtration rate have a cumulative mortality rate of 47%.

Metabolic surgery has been shown to have a beneficial impact on diabetes with Sjöström et al. (Association of bariatric surgery with long-term remission of type 2 diabetes and with microvascular and macrovascular complications. JAMA. 2014 Jun 11;311(22):2297-304) reporting diabetes remission rate two years after surgery of 16.4% for control patients vs. 72.3% for metabolic surgery patients (p<0.001). At 15 years, the diabetes remission rates decreased to 6.5% (for control patients and 30.4% for metabolic surgery patients (p<0.001). The cumulative incidence of microvascular complications was 41.8 per 1000 person-years for control patients and 20.6 per 1000 person-years in the surgery group (p<0.001). In control patients, macrovascular complications were observed in 44.2 per 1000 person-years and 31.7 per 1000 person-years for the surgical group (p=0.001).

In addition, O'Brien et al. (Microvascular Outcomes in Patients With Diabetes After Bariatric Surgery Versus Usual Care: A Matched Cohort Study. Ann Intern Med. 2018 Sep 4;169(5):300-310) also reported that RYGB surgery was associated with significantly lower risk for incident microvascular complications at five years (16.9% for surgical vs. 34.7% for nonsurgical patients. Bariatric surgery was associated with a lower cumulative incidence at 5 years of diabetic neuropathy (7.2% for surgical vs. 21.4% for nonsurgical patients), nephropathy (4.9% for surgical vs. 10.0% for nonsurgical patients), and retinopathy (7.2% for surgical vs. 11.2% for nonsurgical patients).

In an RCT by Cohen et al. (Gastric bypass versus best medical treatment for diabetic kidney disease: 5 years follow up of a single-center open-label randomised controlled trial. EClinicalMedicine. 2022 Nov 11;53:101725) that compared the albuminuria-lowering effects of RYGB to best medical treatment in patients with diabetic kidney disease and obesity, found that the geometric mean for albuminuria levels was 46% lower after metabolic surgery (p=0.001) and was as safe as BMT, with a reduction of 50% of all medications and improved QOL in all domains. RYGB was significantly better in reducing the then American Diabetes Association triple endpoint, thus decreasing cardiovascular risk factors.

Another study presented (Raverdy et al. Data-driven subgroups of type 2 diabetes, metabolic response, and renal risk profile after bariatric surgery: a retrospective cohort study. Lancet Diabetes Endocrinol. 2022;10(3):167-176), aimed to predict the best responders regarding glucocentric and renal outcomes after MBS, according to the subtype of type 2 diabetes. Compared to severe insulin deficient and moderate obesity-associated diabetes, insulin-resistant patients showed better outcomes after metabolic surgery, both in terms of type 2 diabetes remission and increased glomerular filtration rate.

He concluded that metabolic surgery results in significant and durable weight loss whilst offering glycaemic, lipid and hypertension control. In addition, it improves albuminuria and may halt or delay the progression of diabetic kidney disease, even compared to modern pharmacotherapy. Surgery also decreases CV risk factors and severe insulin resistant diabetes (SIRD) patients are better candidates for surgery.

MBS in the elderly population

Dr Abdelrahman A Nimeri (Director of Bariatric Surgery at Brigham & Women’s Hospital, Harvard Medical School) outlined the role and outcomes of metabolic and bariatric surgery in the elderly population. A systematic review by Panagiotou et al (Comparative Effectiveness and Safety of Bariatric Procedures in Medicare-Eligible Patients. JAMA Surg. 2018;153(11):e183326) that included 16 studies and 11,455 patients evaluated elderly patients >65 years who had MBS or non-surgical treatment options. The results showed surgery patients had better weight loss, lower risk of cardiovascular disease (HR=0.59; 95%, CI0.44-0.79) and significantly more improvement in respiratory, metabolic and renal outcomes compared to the non-surgical cohort. In addition, weight loss was greater up to three years with (RYGB) versus SG or LAGB. After one-year, clinical remission of T2DM was higher in the surgical cohort compared to the non-surgical cohort (haemoglobin A1C significantly decreased in RYGB, SG & LAGB). Elderly patients having MBS also had a lower risk of myocardial infarction after MBS compared to patients having orthopaedic or GI surgery and lower rates of CAD up to two years postoperative versus non-surgically treated controls.

Furthermore, Mentias et al. (Long-Term Cardiovascular Outcomes After Bariatric Surgery in the Medicare Population. J Am Coll Cardiol. 2022;79(15):1429-1437. doi:10.1016/j. jacc.2022.01.047) performed 1:1 propensity matching for a cohort of Medicare beneficiaries who had MBS from 2013-2019. In each group, 94,885 elderly patients who had MBS (65% had SG and 33% had RYGB) were matched to a control group of elderly patients with obesity. At a median follow-up of four years, MBS was associated with a lower risk of mortality (9.2 vs 14.7 per 1,000 person-years; HR: 0.63; 95% CI: 0.60-0.66), new-onset HF (HR: 0.46; 95% CI: 0.44-0.49), MI (HR: 0.63; 95% CI: 0.59-0.68), and stroke (HR: 0.71; 95%: CI: 0.65-0.79) (p<0.001). The benefit of MBS was evident in patients who were 65 years and older. In aggregate, these studies showed that MBS conferred a longer life-span and reduced risk of cardiovascular events in elderly patients.

Mabeza et al (Bariatric surgery outcomes in geriatric patients: a contemporary, nationwide analysis. Surg Obes Relat Dis. 2022;18(8):1005-1011) conducted a retrospective administrative database study using a nationwide readmission database examining MBS in patients older than 65 years of age and compared them to a younger cohort aged 45-64 years. The older cohort had a very low in-hospital mortality rate of 0.3%, but compared to the younger cohort, this represented an increased adjusted odds ratio [AOR] of 2.39, 95% [CI]: 1.33–4.30). There were also increased odds of respiratory complications (AOR 5 1.34, 95% CI:1.13–1.59), infectious complications (AOR 5 1.65, 95% CI: 1.25–2.17), renal complications (AOR 5 1.27, 95% CI: 1.12–1.46), and prolonged hospitalization (AOR 5 1.35, 95% CI: 1.24–1.48). There was an inflection point for increased morbidity and mortality after MBS as age increased, and found an inflection point at 59 years of age.

Chao et al (et al. Long-term comparative effectiveness of gastric bypass and sleeve gastrectomy on use of antireflux medication: a differenceindifferences analysis. Surgery for Obesity and Related Diseases. 2022;18(8):1033-1041), conducted a retrospective administrative Medicare database study for outcomes of SG and RYGB in Medicare claims from 2012-2017 for 30,105 patients with three-year follow-up. Among the elderly (n = 8510), SG was associated with lower three-year complications (20.1% vs 24.7%, ARR 95%CI: -7.6% to -1.7%), reinterventions (14.0% vs 21.9%, ARR 95%CI: -10.7% to -5.2%), ED utilization (51.7% vs 57.2%, ARR 95%CI: -9.1% to -1.9%), and rehospitalizations (41.8% vs 45.8%, ARR 95%Ci: -7.5% to -0.5%). Expenditures were $38,632 after the sleeve and $39,270 after the bypass (p=0.60).

Howard et al (Long-term comparative effectiveness of gastric bypass and sleeve gastrectomy on use of antireflux medication: a difference-indifferences analysis. Surgery for Obesity and Related Diseases. 2022;18(8):1033-1041) carried out a retrospective administrative Medicare database study for outcomes of antireflux medication utilization after SG and RYGB in Medicare claims from 2012-2017 in a cohort of 43,364 elderly patients after SG or RYGB in terms. After a five-year follow-up, both SG and RYGB patients took fewer anti-reflux medications than at the time of surgery. In addition, RYGB was associated with significantly lower anti-reflux medication usage (46% for RYGB vs 60% for SG patients). Similarly, a significant decrease in the use of proton pump inhibitors (PPI) specifically in RYGB vs SG after 3, 4 and 5 years was observed.

A retrospective administrative Medicare database study by Howard et al (Howard R, Chao GF, Yang J, et al. Medication Use for Obesity-Related Comorbidities after Sleeve Gastrectomy or Gastric Bypass. JAMA Surg. 2022;157(3):248-256) compared medication use for diabetes, hypertension, and hyperlipidaemia as well as the outcomes of SG and RYGB in Medicare beneficiaries between 2012 to 2018. The study examined DM, HTN, hyperlipidaemia outcomes & restarting medications for those who were able to stop them after SG and RYGB. Patients after RYGB were more likely, after 5 years, to discontinue diabetes medications (discontinuation rates of 74.7% after RYGB vs 72% after SG) and fewer patients after RYGB restarted their diabetes medication (30.2% after RYGB and 35.6% after SG). Similarly, patients after RYGB were more likely to discontinue their antihypertensive medications after 5 years (53.3% after RYGB vs 49.4% after SG). In aggregate, these studies demonstrated advantages to RYGB over SG with respect to medication usage in the elderly population.

“Metabolic and Bariatric Surgery is safe in the elderly population,” he concluded. “Risk assessment is paramount and Sleeve gastrectomy may have a safer profile while Roux-en-Y gastric bypass better resolution of obesity-related medical problems.”

Surgical treatment in adolescents <18

Professor Aayed Alqahtani (New You Medical Center, Riyadh, Saudi Arabia) presented the results of MBS in aged <18 years. In his prospective cohort study (Alqahtani et al. Ten-Year Outcomes of Children and Adolescents Who Underwent Sleeve Gastrectomy: Weight Loss, Comorbidity Resolution, Adverse Events, and Growth Velocity. J Am Coll Surg. 2021 Dec;233(6):657-664) 2,504 children and adolescents with class II/III obesity who were enrolled in a multidisciplinary, family-based paediatric obesity management program underwent LSG between 2008 and 2021. Complete comorbidity remission at long-term follow-up was observed in 74%, 59%, and 64% of type 2 diabetes, dyslipidaemia and hypertension cases, respectively.

Long-term follow-up after SG in children and adolescents demonstrated durable weight loss, maintained comorbidity resolution, and unaltered growth. A second study also by Alqahtani et al. (Laparoscopic Sleeve Gastrectomy in Children Younger Than 14 Years: Refuting the Concerns. Ann Surg. 2016 Feb;263(2):312-9), 116 children younger than 14 years (mean ± SD, 11.2 ± 2.5 years) underwent LSG and were compared with the 1:1 matched group of nonsurgical weight management. The surgical children experienced significantly higher growth, gaining 0.9 mm more per month on average. Compared with 158 adolescents (age, 17.3 ± 2.0 years) who underwent LSG in our institution, children younger than 14 years had a significantly lower prevalence of comorbidities (p<0.001) but similar resolution rates (p=0.72-0.99).

According to American Academy of Pediatrics policy statement on metabolic and bariatric surgery in children and adolescents, based on multiple systematic reviews, recommends surgery for: n Children and adolescents with BMI ≥35 kg/m2 or above the 95th percentile for age + multiple comorbidities n Children and adolescents with class 3 obesity, BMI≥40 kg/m2 (whichever is lower). A prospective study by Inge et al (TeenLABS Consortium. Weight Loss and Health Status Three Years after Bariatric Surgery in Adolescents. N Engl J Med. 2016 Jan 14;374(2):113-23) reported the mean weight had decreased by 27% in the total cohort, by 28% (95% CI, 25 to 30) among participants who underwent gastric bypass, and by 26% among those who underwent sleeve gastrectomy and significant improvements in weight, cardiometabolic health and weight-related quality of life.

The role of Endoscopic Sleeve Gastroplasty was determined in a study by Alqahtani et al. (Endoscopic Sleeve Gastroplasty in 109 Consecutive Children and Adolescents With Obesity: Two-Year Outcomes of a New Modality. Am J Gastroenterol. 2019 Dec;114(12):1857-1862) that included 109 patients. The mean % total weight loss at 6, 12, 18, and 24 months was 14.4%±6.5%, 16.2%±8.3%, 15.4%±9.2%, and 13.7%±8.0%, respectively.

For patients with Prader Willi syndrome, a systematic review and metaanalysis by Wolfe et al (Metabolic and bariatric surgery for obesity in Prader Willi syndrome: systematic review and meta-analysis. Surg Obes Relat Dis. 2023 Feb 1:S1550-7289(23)00043-6) included 67 patients from 22 articles met criteria for inclusion in the meta-analysis. Patients were organized into three groups: laparoscopic sleeve gastrectomy (LSG), gastric bypass (GB), and biliopancreatic diversion (BPD). All groups experienced a significant decrease in BMI at One year with a mean reduction in BMI of 14.7 kg/ m2 (p<0.001). The LSG groups (n=26) showed significant change from baseline in years 1, 2, and 3 (p value at year 3 =0.002) but did not show significance in years 5, 7, and 10. The GB group (n = 10) showed a significant reduction in BMI of 12.1 kg/m2 in the first 2 years (p=0.001). The BPD group (n=28) had a significant reduction in BMI through seven years with an average reduction of 10.7 kg/m2 (p=0.02) at year seven.

A second study on Prader-Willi syndrome by Alqahtani et al. (Laparoscopic sleeve gastrectomy in children and adolescents with PraderWilli syndrome: a matched-control study. Surg Obes Relat Dis. 2016 Jan;12(1):100-10) 24 PWS patients had a mean preoperative BMI of 46.2 ± 12.2 kg/m2 . BMI change at the first, second, third, fourth, and fifth annual visits was -14.7 (n=22 patients), -15.0 (n=18), 12.2 (n=13), -12.7 (n=11), and -10.7 (n=7), respectively, in the PWS group, whereas the non-PWS group had a BMI change of -15.9 (n=67), -18.0 (n=50), -18.4 (n=47), -18.9 (n=26) and -19.0 (n=20), respectively. PWS children and adolescents underwent effective weight loss and resolution of co-morbidities after LSG, without mortality, significant morbidity, or slowing of growth.

A study by Jackson et al (Laparoscopic sleeve gastrectomy versus laparoscopic Roux-en-Y gastric bypass in the pediatric population: an MBSAQIP analysis. Surg Obes Relat Dis. 2020 Feb;16(2):254-260) that compared patients aged ≤21 years who underwent LSG or LRYGB found patients who underwent LRYGB had an increased body mass index and a higher rate of obesity-related co-morbidities. The LRYGB group had a significantly increased rate of major complications within the first 30 days in both the unmatched cohort (4.55% versus 1.34%, p<0.001) and the propensity-score matched cohort (4.57% versus 0.91%, p<0.001). Inge et al (Comparison of Surgical and Medical Therapy for Type 2 Diabetes in Severely Obese Adolescents. JAMA Pediatr. 2018;172(5):452-460) reported that surgical treatment of adolescents with severe obesity with type 2 diabetes was associated with better glycaemic control, reduced weight and improvement of other comorbidities, compared with medical therapy.

Alqahtani explained that adolescents with T2DM compared to adults have hyperresponsive beta cells, lower insulin sensitivity, and more rapid deterioration of beta cell function. The TODAY Study Group reported 50% of adolescents with T2DM treated with metformin ± LMT progressed to exogenous insulin dependence in one year (N Engl J Med. 2012 Jun 14;366(24):2247-56). Moreover, the RISE Consortium (Impact of Insulin and Metformin Versus Metformin Alone on β-Cell Function in Youth With Impaired Glucose Tolerance or Recently Diagnosed Type 2 Diabetes. Diabetes Care. 2018 Aug;41(8):1717-1725) reported metformin does not slow beta cell deterioration in adolescents with IGT or T2DM.

Adolescent MBS

Dr Thomas Inge (Northwestern University Feinberg School of Medicine) began by highlighting a large observational study (Inge et al Teen-LABS Consortium. Weight Loss and Health Status 3 Years after Bariatric Surgery in Adolescents. N Engl J Med. 2016 Jan 14;374(2):113-23) that reported significant improvements in weight, cardiometabolic health, and weight-related quality of life at three years after the procedure.

He also presented data from a retrospective analysis of the MBSAQIP database by Jackson et al (Laparoscopic sleeve gastrectomy versus laparoscopic Roux-en-Y gastric bypass in the pediatric population: an MBSAQIP analysis. Surg Obes Relat Dis. 2020 Feb;16(2):254-260) showing results from patients aged ≤21 years – 2,911 (81.52%) who underwent LSG and 660 (18.48%) underwent LRYGB. LSG demonstrated a significantly decreased rate of major complications in the first thirty days vs. LRYGB (lower mortality, reop, ED visits in LSG). LSG also showed greater perioperative safety than RYGB in the paediatric age group. A prospective analysis of Teen-LABS micronutrient data at five years (Xanthakos et al. Teen Longitudinal Assessment of Bariatric Surgery Consortium. Nutritional Risks in Adolescents After Bariatric Surgery. Clin Gastroenterol Hepatol. 2020 May;18(5):1070-1081.e5. doi 10.1016/j. cgh.2019.10.048) revealed multiple micronutrient deficiencies in 59% of RYGB, and only 27% of VSG, and LSG showed greater nutritional safety in the long term than RYGB in adolescents.

He then discussed the long-term impact T2DM has on young adults and cited a study by Bjornstad et al. (TODAY Study Group; Long-Term Complications in Youth-Onset Type 2 Diabetes. N Engl J Med. 2021 Jul 29;385(5):416-426) that reported participants who had onset of type 2 diabetes in youth (mean age 26.4±2.8 years, and the mean time since diagnosis of diabetes 13.3±1.8 years), the risk of complications, including microvascular complications, increased steadily over time and affected most participants by the time of young adulthood. Complications were more common among participants of minority races and ethnic groups and among those with hyperglycaemia, hypertension, and dyslipidaemia.

He added that the drugs seemed to be ineffective, for example, the TODAY Study Group (N Engl J Med. 2012 Jun 14;366(24):2247-56.) reported 50% of adolescents with T2DM treated with metformin ± LMT progressed to exogenous insulin dependence in one year. Moreover, the RISE Consortium (Diabetes Care. 2018 Aug;41(8):1717-1725) found metformin does not slow beta cell deterioration in adolescents with IGT or T2DM. In comparison, MBS, compared to medical treatment of youth people with obesity and T2DM was associated with lower odds of diabetic kidney disease over five years (Bjornstad Effect of Surgical Versus Medical Therapy on Diabetic Kidney Disease Over 5 Years in Severely Obese Adolescents With Type 2 Diabetes. Diabetes Care. 2020 Jan;43(1):187-195).

Inge concluded that SG has a greater safety profile and comparable weight loss to RYGB in adolescents and MBS is a reasonable treatment option for paediatric patients with severe obesity and type 2 diabetes, and in children with severe obesity, MBS reverses T2DM. Paediatric data supporting use of MBS in Class 1 obesity are lacking, but based on adult MBS outcomes and virulence of paediatric T2DM, a reasonable argument could be made to extend study outcomes of MBS in children with Class 1 obesity and T2DM.

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