Results of The Comparative Study of 200 Cases: One Anastomosis Gastric Bypass vs Roux-en-Y Gastric Bypass

American Society for Metabolic and Bariatric Surgery position statement on one-anastomosis gastric bypass

The following position statement is issued by the American Society for Metabolic and Bariatric Surgery in response to inquiries made to the society by patients, physicians, society members, hospitals, health insurance payors, and others regarding one-anastomosis gastric bypass as a treatment for obesity and metabolic disease. This statement is based on current clinical knowledge, expert opinion, and published peer-reviewed scientific evidence available at this time. The statement may be revised in the future as more information becomes available.

Comparison of Single Versus Double Anastomosis Bariatric Metabolic Surgery in Obesity: a Systematic Review and Meta-analysis

Major BMS are modified through loop rather than Roux-en-Y type reconstruction recently, and this study systematically reviews the BMS from the perspective of SA (single anastomosis) and DA (double anastomosis) procedures, aiming to research the differences among bariatric procedures. A total of 39 studies compared SA- and DA-BMS were finally eligible for analysis after searching in PubMed, Web of Science, and Cochrane Library. Compared with DA, SA shortens operative time and decreases complications especially obstruction, internal hernia, and reoperation. SA-GB (gastric bypass) has significantly higher %TWL and T2DM remission rate than DA-GB 1- and 5-year postoperatively. SA-DS (duodenal switch) has similar 1-year %TWL and lower 5-year %TWL, and comparable 1- and 5-year T2DM remission with DA-DS. SA provides significant advantages about simplicity and safety. This, together with the shorter learning curve, makes SA a promising choice.

Comparison of Efficacy and Safety Between Roux-en-Y Gastric Bypass (RYGB) vs One Anastomosis Gastric Bypass (OAGB) vs Single Anastomosis Duodeno-ileal Bypass with Sleeve Gastrectomy (SADI-S): a Systematic Review of Bariatric and Metabolic Surgery

In recent years, combined restrictive and hypo-absorptive procedures have gained widespread acceptance. The rationale of this systematic review is to compare the safety and efficacy between Roux-en-Y gastric bypass (RYGB), one anastomosis gastric bypass (OAGB) and single anastomosis duodeno-ileal bypass with sleeve gastrectomy (SADI-S). Eighteen eligible studies were finalized for this review. Weight loss outcomes were greater with SADI-S (5 years) and OAGB (10 years). SADI-S offered better resolution of diabetes whereas hypertension and dyslipidaemia resolution were better with OAGB. Although early complications and mortality were higher with SADI-S, late complications were more frequent with RYGB. Both SADI-S and OAGB are as effective as RYGB for weight loss, but OAGB offers lesser complications. However, more data is imperative to determine the next gold standard procedure.

Management of leaks following one-anastomosis gastric bypass: an updated systematic review and meta-analysis of 44 318 patients

INTRODUCTION

One-anastomosis gastric bypass (OAGB) complication, such as leakage, can be dangerous and should be managed properly, yet little data exist in the literature regarding the management of leaks after OAGB, and there are no guidelines to date.

METHODS

The authors performed a systematic review and meta-analysis of the literature and 46 studies, examining 44 318 patients were included.

RESULTS

There were 410 leaks reported in 44 318 patients of OAGB published in the literature, which represents a prevalence of 1% of leaks after OAGB. The surgical strategy was very variable among all the different studies; 62.1% of patients with leaks had to undergo another surgery due to the leak. The most commonly performed procedure was peritoneal washout and drainage (with or without T-tube placement) in 30.8% of patients, followed by conversion to Roux-en-Y gastric bypass in 9.6% of patients. Medical treatment with antibiotics, with or without total parenteral nutrition alone, was conducted in 13.6% of patients. Among the patients with the leak, the mortality rate related to the leak was 1.95%, and the mortality due to the leak in the population of OAGB was 0.02%.

CONCLUSION

The management of leaks following OAGB requires a multidisciplinary approach. OAGB is a safe operation with a low leak risk rate, and the leaks can be managed successfully if detected in a timely fashion.

Efficacy and Safety of One Anastomosis Gastric Bypass Versus Roux-en-Y Gastric Bypass for Obesity: a Meta-analysis and Systematic Review

The objective of this review is to systematically review the efficacy and safety outcomes of one anastomosis gastric bypass (OAGB) with Roux-en-Y gastric bypass (RYGB). From inception to July 4, 2022, a systematic literature search was performed using PubMed, Embase, and Cochrane Library for randomized clinical trials comparing OAGB with RYGB in obesity. A meta-analysis performed using the RevMan 5.4.1 software evaluations was completed. We identified 1217 reports; after exclusions, eight trials with a total of 931 patients were eligible for analysis. Compared with RYGB, OAGB had multiple advantageous indexes. Examples include percent of excess weight loss (%EWL) at 12 months (P = 0.009), body mass index (BMI) at 2 years (P < 0.00001), early postoperative complication (P = 0.04), remission of dyslipidemia (P < 0.0001), and operative time (P < 0.00001). No significant statistical difference was observed in BMI at 6 months, %EWL at 6 months, BMI at 12 months, percent of excess body mass index loss (%EBMIL) at 2 years, BMI at 5 years, intraoperative complications, late postoperative complications, remission of type 2 diabetes mellitus, and dyslipidemia or gastroesophageal reflux disease remission between OAGB and RYGB. OAGB is no less effective than RYGB; no significant differences in weight loss efficacy were observed, and more large and long-term randomized controlled trials are needed to verify this. In addition, studies have shown that OAGB has a shorter operation time, fewer early postoperative complications, and a shorter learning curve, making it easier for young surgeons to perform.

Comparison of the Long-term Outcomes of RYGB and OAGB as Conversion Procedures After Failed LSG - a Case-Control Study

OBJECTIVE

To compare the effect of RYGB and OAGB on patients after failed treatment of obesity by laparoscopic sleeve gastrectomy (LSG).

STUDY DESIGN

A case-control study based on a prospectively maintained database of reoperated patients after failed LSG, which included 33 patients who underwent RYGB conversion and 47 patients who underwent OAGB conversion.

RESULT

The mean %EBWL after a 5-year follow-up for RYGBc vs OAGBc was 84.04% vs 72.95% (p = 0.2176), respectively. Complete long-term diabetes remission was observed significantly more frequently in the OAGBc than in the RYGBc group (97.3% vs 33%; p = 0.035). There were no other statistically significant differences in the remission rate of comorbidities between RYGBc and OAGBc: hypertension 30% vs 27.3% (p = 0.261), dyslipidemia 83.3% vs 59.1% (p = 0.277), OSAS 100% vs 60% (p = 0.639), and GERD 40% vs 71.4% (p > 0.99), respectively. 7 patients were newly diagnosed with GERD after OAGBc and none after RYGBc. There were no statistically significant differences in the number of complications between the OAGBc and RYGB groups. The Comprehensive Complication Index was 17.85 (± IQR 29.6) in the OAGBc group and 14.92 (± IQR 21.75) in the RYGBc group (p = 0.375).

CONCLUSION

The authors recognized complete long-term type 2 diabetes remission after conversion surgery as the most relevant difference, where the OAGB variety was found superior for its better efficacy. Any other statistically significant differences in the consequences after both conversion procedures used after the failure of LSG have not been stated. Both methods therefore can be considered to complete the initial treatment, considering the preferences and individual burdens of the patients.

IFSO Update Position Statement on One Anastomosis Gastric Bypass (OAGB)

The International Federation for the Surgery of Obesity and Metabolic Disorders (IFSO) issued a position statement on the role of one anastomosis gastric bypass (OAGB) in the field of bariatric/metabolic surgery in 2018 De Luca et al. (Obes Surg. 28(5):1188-206, 2018). This position statement was issued by the IFSO OAGB task force and approved by the IFSO Scientific Committee and IFSO Executive Board. In 2018, the OAGB task force recognized the necessity to update the position statement in the following 2 years since additional high-quality data could emerge. The updated IFSO position statement on OAGB was issued also in response to inquiries to the IFSO by society members, universities, hospitals, physicians, insurances, patients, policy makers, and media. The IFSO position statement on OAGB has been reviewed within 2 years according to the availability of additional scientific evidence. The recommendation of the statement is derived from peer-reviewed scientific literature and available knowledge. The IFSO update position statement on OAGB will again be reviewed in 2 years provided additional high-quality studies emerge.

One anastomosis gastric bypass vs. Roux-en-Y gastric bypass, remedy for insufficient weight loss and weight regain after failed restrictive bariatric surgery

Background

Failure occurs in up to 60% of the patients that were treated with primary restrictive bariatric operations such as Laparoscopic Adjustable Gastric Banding (LAGB), or restrictive/metabolic operations like Laparoscopic Sleeve Gastrectomy (LSG). Insufficient weight loss and weight regain are the most commonly reported reasons of failure. The aim of this retrospective multicenter study was to compare One Anastomosis Gastric Bypass (OAGB) to Roux-en-Y Gastric Bypass (RYGB) as a revisional procedure in terms of weight loss, procedure time, complication rate and morbidity.

Methods

491 patients operated on between 2012 and 2017 for failed restrictive surgery were included in this study (OAGB (n=185) or RYGB (n=306)). Failure was defined as total weight loss (TWL) less than 25%, excess weight loss (EWL) less than 50% and/or a remaining body mass index (BMI) larger than 40 kg/m2 at two years of follow up. Primary outcome measures were %TWL and % excess BMI loss (EBMIL) at 12, 24 and 36 months of follow-up. Secondary outcomes were procedure time, reduction of comorbidity, early and late complication rate, and mortality.

Results

%TWL was significantly larger in the OAGB group at 12 months (mean 24.1±9.8 vs. 21.9±9.7, p = 0.023) and 24 months (mean 23.9±11.7 vs. 20.5±11.2, p = 0.023) of follow-up. %EBMIL was significantly larger in the OAGB group at 12 months (mean 69.0±44.6 vs. 60.0±30.1, p = 0.014) and 24 months (mean 68.6±51.6 vs. 56.4±35.4, p = 0.025) of follow-up. Intra-abdominal complications (leakage, bleeding, intra-abdominal abscess and perforation) occurred less frequently after revisional OAGB (1.1% vs. 4.9%, p = 0.025). Surgical intervention for biliary reflux (5.4% vs. 0.3%, p < 0.001) was more prevalent in the OAGB group. Surgical intervention for internal herniation (0.0% vs. 4.9%, p = 0.002) was more prevalent in the RYGB group.

Conclusions

This study suggests that OAGB is superior to RYGB as a remedy for insufficient weight loss and weight regain after failed restrictive surgery with more weight loss and a lower early complication rate. To substantiate these findings, further research from prospective randomized controlled trials is needed.

Short-Term Changes on Body Composition and Bone Mass After One-Anastomosis Gastric Bypass: a Prospective Observational Study

PURPOSE

Bariatric surgery generates a large weight loss. It is considered a successful surgery when 50% of the excess weight loss is reached. However, this measure does not include some variables that may have a direct impact on a patient's health, such as fat-free mass (FFM) or bone mass. Therefore, the aim of this study is to evaluate body composition and bone mass in patients undergoing one-anastomosis gastric bypass (OAGB).

METHODS

A prospective observational study was performed in patients undergoing OAGB. Body composition and bone mass were evaluated by bioelectrical impedance analysis at baseline (1 day prior to surgery), at 6 and 12 months after surgery.

RESULTS

A total of 94 patients (67% females and 33% males) were included in the study. The excess BMI loss at 6 and 12 months after surgery was 97.9 ± 20.1% and 110.2 ± 30.5% respectively. The FFM showed a reduction of 6.6 ± 4.8 kg (p < 0.01) 6 months after surgery and of 7.9 ± 4.9 kg (p < 0.01) at 12 months, meaning a decrease of 10.5 ± 7.3% and a 12.9 ± 6.6% respectively. The bone mass decrease was 10.1 ± 6.9% (p < 0.01) and 12.9 ± 6.5% (p < 0.01) at 12 months after OAGB.

CONCLUSIONS

OAGB obtains a relevant weight loss in patients with morbid obesity, mainly, due to fat mass reductions. However, this procedure also provokes FFM and bone mass decreases, especially in females, but not significantly greater than other restrictive or mixed procedures.

Areas of Non-Consensus Around One Anastomosis/Mini Gastric Bypass (OAGB/MGB): A Narrative Review

PURPOSE

One anastomosis/mini gastric bypass (OAGB/MGB) is now an established bariatric and metabolic surgical procedure with good outcomes. Despite two recent consensus statements around OAGB/MGB, there are some issues which are not accepted as consensus and need more long-term data and research.

MATERIAL AND METHODS

After identifying the topic of non-consensus from the two recent OAGB/MGB consensuses, PubMed, Scopus, and Cochrane were searched for articles published by November 2020.

RESULTS

In this study, we evaluated these non-consensus topics around OAGB/MGB and all related articles on these topics were assessed by authors to have an argument on these items.

CONCLUSION

There is enough evidence to include OAGB/MGB as an accepted standard bariatric and metabolic surgical procedure. However, long-term data and more research are needed to have a consensus in all aspects including these non-consensus topics.

One anastomosis gastric bypass vs. Roux-en-Y gastric bypass: a 5-year follow-up prospective randomized trial

BACKGROUND

One anastomosis gastric bypass (OAGB) is a relatively novel technique with excellent outcomes, comparable to most accepted procedures. Our aim was to compare OAGB and Roux-en-Y gastric bypass (RYGB) in terms of percent of excess weight lost (%EWL) and resolution of comorbidities.

METHODS

Thirty-three patients were randomly assigned (1:2) to two groups (OAGB = 9 and RYGB = 24). Patients were analyzed prospectively.

RESULTS

The 5-year follow-up was 85% (28 patients). Both groups were comparable preoperatively in age, weight, body mass index (BMI), and excess weight. One intraoperative complication in OAGB group and no major postoperative complications for both groups were recorded. Progressive decrease in weight, BMI, and %EWL was observed at 1, 6, 12 months, and 5 years, with no differences between groups. Regarding comorbidities, we registered complete remission in type 2 diabetes mellitus (T2DM), insulin resistance, and dyslipidemia with OAGB. RYGB group reported complete remission in T2DM, insulin resistance, dyslipidemia, and gastroesophageal reflux disease (GERD). Mean operative time were 113.3 min ± 41.2 and 143.7 min ± 21.85 for OAGB and RYGB respectively. Mean number of reloads used was 5 for OAGB and 7 for RYGB, which demands further investigations. Postoperative pain was significantly higher in RYGB group. Hospital stay was 3 days for both groups.

CONCLUSION

At 5-year follow-up, patients of both techniques achieved similar outcomes in terms of %EWL and resolution of comorbidities, without early or mid-term major complications and no mortality. OAGB demonstrated less use of surgical stapling and unexplainably less postoperative pain compared to RYGB.

One Anastomosis Gastric Bypass Versus Roux-en-Y Gastric Bypass for Morbid Obesity: an Updated Meta-Analysis

INTRODUCTION

We aim to review the available literature on morbidly obese patients treated with one anastomosis gastric bypass (OAGB) or Roux-en-Y gastric bypass (RYGB) in order to compare the clinical outcomes of the two methods.

METHODS

A literature search was performed in PubMed, Cochrane Library, and Scopus, in accordance with the PRISMA guidelines.

RESULTS

Sixteen studies were included in the qualitative analysis, and 11 studies were included in the quantitative analysis (meta-analysis), incorporating 12,445 patients. OAGB was associated with shorter mean operative time. The length of hospital stay was comparable between the two procedures. The incidence of leaks, marginal ulcer, dumping, bowel obstruction, revisions, and mortality was similar between the two approaches. The incidence of malnutrition was increased in patients treated with OAGB, while the incidence of internal hernia and bowel obstruction was greater in the RYGB group. In addition, the OAGB was associated with greater % excess weight loss (%EWL) at 1, 2, and 5 years postoperatively. The rate of diabetes remission was greater in the OAGB group. Nonetheless, the rate of hypertension and dyslipidemia remission was similar between OAGB and RYGB.

CONCLUSION

The present meta-analysis is the best currently available evidence on the topic and demonstrates the superiority of OAGB compared with RYGB, in terms of weight loss and diabetes remission. However, the OAGB was associated with a significantly higher incidence of malnutrition, thus indicating the significant malabsorptive traits of this operation.

Laparoscopic mini/one anastomosis gastric bypass: anatomic features, imaging, efficacy and postoperative complications

Laparoscopic mini/one anastomosis gastric bypass (MGB/OAGB) is an increasingly used bariatric surgical procedure. This surgical technique is effective in terms of both weight loss and the resolution of comorbidities, but it is not without complications. To report our experience in MGB/OAGB, assessing comorbidities and complications, and to illustrate post-surgical anatomy and radiological appearance of complications, a single-centre retrospective study of 953 patients undergoing MGB/OAGB between January 2005 and September 2018 was done. The inclusion criteria: body mass index (BMI) of 40 kg/m² or higher or BMI between 35 and 40 kg/m² with significant comorbidities not responsive to medical therapies. In the postoperative period, all patients were evaluated with clinical and laboratory tests and radiological examinations (upper gastrointestinal series, computed tomography and magnetic resonance imaging). Median weight was 126.69 kg and mean BMI was 49.4 kg/m². Regarding comorbidities, 37.2%, 52.8%, 46.7% and 43.2% of patients presented with preoperatively diagnosed type 2 diabetes mellitus (T2DM), hypertensive disease, dyslipidaemia and obstructive sleep apnoea syndrome (OSAS), respectively. Median excess weight loss at 6, 12, 24 and 60 months after surgery was 33.45%, 53.81%, 68.75% and 68.80%, respectively. The remission of comorbidities was 91.4% for T2DM, 93.7% for hypertensive disease, 90.3% for dyslipidemia and 93.4% for OSAS. Early and late complication rates identified with radiological examinations were 1.5% and 1.6%, respectively. MGB/OAGB was effective for weight loss and comorbidities remission. Complications occurred at lower rate than with other surgical procedures were identified with imaging; CT was the main radiological technique.

Impact of limb length on nutritional status in one-anastomosis gastric bypass: 3-year results

BACKGROUND

Bariatric metabolic surgery is a well-established treatment option associated with significant weight loss and an improvement of metabolic co-morbidities. However, the changes in gastrointestinal anatomy frequently result in nutritional deficiencies.

OBJECTIVE

To evaluate the impact of biliopancreatic limb length in one-anastomosis gastric bypass (OAGB) on micronutrient and protein deficiencies.

SETTING

University hospital, Austria.

METHODS

All patients that were (1) undergoing OAGB between 2012 and 2014, and (2) had at least 3 postoperative follow-up visits were retrospectively analyzed. Systemic levels of parathyroid hormone, vitamins (A, D, E, and B12), folic acid, magnesium, calcium, iron, albumin, and ferritin were correlated to biliopancreatic limb length as follows: short limb (150 cm), intermediate limb (200 cm), and long limb (250 cm).

RESULTS

A total of 155 patients fulfilled inclusion criteria (female/male: n = 111/44). OAGB led to a mean percent excess weight loss of 79.9 (±24.2) and a reduction of mean body mass index from 45.4 kg/m² (±6.1 kg/m²) at baseline to 30.2 kg/m² (±9.9 kg/m²). Preoperative deficiencies were seen in 25-hydroxy-vitamin D (93.8%), folic acid (27.6%), ferritin (4.1%), vitamin A (5.5%), and vitamin B12 (2.3%). In patients with long limb, systemic folic acid levels were significantly lower after 24 months postoperatively compared with short and intermediate limb (P < .05). No difference was observed for vitamin D, A, E, B12, and iron and no patient suffered from severe protein malnutrition.

CONCLUSION

Nutritional deficiencies were common after OAGB without severe deficiencies in biliopancreatic limb lengths ranging from 150 to 250 cm. A trend can be observed with more pronounced deficiencies with intermediate and long limb lengths without significant differences for most micronutrients.

One Anastomosis Gastric Bypass/Minigastric Bypass in Patients with BMI < 35 kg/m2 and Type 2 Diabetes Mellitus: Preliminary Report

INTRODUCTION

Obesity in the world has been increasing, and the number of diabetic patients will increase by 114%, and the best treatment results are achieved through surgery. Several techniques have been described; the gastric bypass of an anastomosis (MGB/OAGB) has been gaining popularity for its simplicity and good results. We present a prospective study with this technique in 16 mild obesity patients with type 2 diabetes mellitus or peripheral insulin resistance.

OBJECTIVE

To evaluate weight loss as well as metabolic changes by measuring fasting glycemia and Hb A1c after 1 year of follow-up.

MATERIAL AND METHODS

Sixteen patients were operated on with the OAGB/MGB technique from September 2014 to January 2016, with some form of metabolic syndrome, whether DM2, RPI, HBP, or dyslipidemia, including patients in the study with a follow-up of at least 12 months.

RESULTS

There were 13 cases of female sex and 3 of male, average age of 42.9 years, with an average weight of 87.7 kg and BMI of 32.2 kg/m². Metabolic values were fasting glycemia of 193.6 ± 52.9 mg/dl and HbA1c of 8.4% ± 1 (preop) and glycemia posop, 78.8 ± 7.6 mg/dl; HbA1c posop, 6.1 ± 0.2; preop weight, 87.7 ± 14 kg (69-116); weight posop, 66.8 ± 10.5 kg (49-90); BMI preop, 32.2 ± 1.8 (30-34.9); BMI posop, 25.4 ± 1.7 (21.7-27.6); percentage of excess weight lost, 87.6 ± 11.8 (70.9-100) % with 100% remission of diabetes.

CONCLUSION

The results show the benefits of MGB/OAGB in mild obese diabetic patients.