Single-anastomosis gastric bypass (SAGB): appraisal of clinical evidence

Laparoscopic sleeve gastrectomy vs one-anastomosis gastric bypass 5-year follow-up: a single-blinded randomized controlled trial

BACKGROUND

Laparoscopic sleeve gastrectomy (LSG) is the most performed bariatric procedure worldwide, whereas one-anastomosis gastric bypass (OAGB) is the third most performed procedure. Both procedures have reported good weight loss (WL) and low complications. However, should both have differences in the durability of WL and malnutrition?

METHODS

A single-blinded, randomized controlled trial of 300 patients was conducted to compare the outcomes of LSG and OAGB over a 5-year follow-up. The primary endpoint was WL in percentages of total WL (%TWL) and excess WL (%EWL). The secondary endpoints were complications, gastroesophageal reflux disease (GERD), associated medical problems, bariatric analysis and reporting outcome system (BAROS) assessment, and weight recurrence (WR).

RESULTS

Overall, 201 patients (96 in the LSG group and 105 in the OAGB group) completed 5 years of follow-up. OAGB had significantly higher %TWL and %EWL than those of LSG throughout the follow-up. LSG had significantly higher WR and GERD. Both procedures had significant improvement in associated medical problems and BAROS scores compared with baseline, with no significant difference. WR was associated with higher relapse of associated medical conditions after initial remission and with lower BAROS scores regarding WL scores.

CONCLUSION

OAGB had significantly higher WL, less WR, and less GERD. However, it had a higher incidence of bile reflux. Both procedures had comparable complication rates, excellent remissions in associated medical problems, and improved quality of life. WR was associated with significantly more relapse of associated medical problems and significantly lower BAROS scores.

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.

GERD after Bariatric Surgery: A Review of the Underlying Causes and Recommendations for Management

PURPOSE OF REVIEW

GERD after bariatric surgery is an ongoing concern for bariatric surgeons and their patients. This paper reviews the association of persistent or de novo GERD after multiple types of bariatric surgery, and focuses on the work up and management of GERD after SG.

RECENT FINDINGS

Two recent large, multicenter randomized clinical trials have shown stronger associations between SG and GERD compared to RYGB. A large group of internationally recognized bariatric surgeons collaborated on 72 consensus statements to help guide the bariatric community on the subject of redo surgeries after SG, including as it pertains to GERD. We present an algorithm that consolidates the best-practices recommendations of the work-up and management of GERD after sleeve gastrectomy, and mention areas of persistent controversy where future research is warranted.

One anastomosis gastric bypass as a primary bariatric surgery: MBSAQIP database analysis of short-term safety and outcomes

BACKGROUND

One anastomosis gastric bypass (OAGB) is described as a simpler, potentially safe, and effective bariatric-metabolic procedure that has been recently endorsed by the American Society of Metabolic and Bariatric Surgery.

OBJECTIVES

First, we aim to compare the 30-day outcomes between OAGB and other bypass procedures: Roux-en-Y gastric bypass (RYGB) and single anastomosis duodenoileal bypass with sleeve gastrectomy (SADI-S). Second, identify the odds between postoperative complications and each surgical procedure.

METHODS

Patients who underwent primary OAGB, RYGB, and SADI-S were identified using the MBSAQIP database of 2020 and 2021. An analysis of patient demographics and 30-day outcomes were compared between these three bypass procedures. In addition, a multilogistic regression for overall complications, blood transfusions, unplanned ICU admissions, readmission, reoperation, and anastomotic leak stratified by surgical procedure was performed.

RESULTS

1607 primary OAGBs were reported between 2020 and 2021. In terms of patient demographics, patients who underwent RYGB and SADI-S showed a higher incidence of comorbidities. On the other hand, OAGB had shorter length of stay (1.39 ± 1.10 days vs 1.62 ± 1.42 days and 1.90 ± 2.04 days) and operative times (98.79 ± 52.76 min vs 125.91 ± 57.76 min and 139.85 ± 59.20 min) than RYGB and SADI-S. Similarly, OAGB showed lower rates of overall complications (1.9% vs 4.5% and 6.4%), blood transfusions (0.4% vs 1.1% and 1.8%), unplanned ICU admission (0.3% vs 0.8% and 1.4%), readmission (2.4% vs 4.9% and 5.0%), and reoperation (1.2% vs 1.9% and 3.1%). A multilogistic regression analysis was performed, RYGB and SADI-S demonstrated higher odds of 30-day complications.

CONCLUSION

The incidence of primary OAGB has increased since its approval by ASMBS, from 0.05% reported between 2015 and 2019 to 0.78% between 2020 and 2021. OAGB had better 30-day outcomes and shorter operative times than RYGB and SADI-S and therefore, could be considered a viable alternative.

Is one-anastomosis gastric bypass a good revisional bariatric surgery? A single-center retrospective cohort study

<b><br>Introduction:</b> The rate of revisional surgeries following sleeve gastrectomy (SG) has increased. One-anastomosis gastric bypass (OAGB) appears to have multiple advantages as a primary bariatric procedure. OAGB as revisional surgery is still being investigated.</br> <b><br>Aim:</b> Evaluation of the efficacy and safety of OAGB performed as a post-SG revisional surgery.</br> <b><br>Materials and methods:</b> A single-center, retrospective cohort study was conducted using a routinely collected database of adults undergoing revisional OAGB after SG. A survey of patients was conducted, obtaining information on changes in body weight and improvement in gastroesophageal reflux disease (GERD) and obesity-related diseases.</br> <b><br>Results:</b> The study group included 74 patients: 59 women (80%) and 15 men, mean age of 41.61 9.21 years. The most common indication for OAGB was weight regain. The follow-up was up to 7 years, the mean time was 3.58 1.21 years. The mean preoperative body mass index (BMI) was 40.38 6.15. All patients experienced significant weight loss, reaching a BMI of 33.61 (27.28- 37.13) at the last observation. After surgery, 35% of patients achieved successful weight loss and 48% of patients achieved remission or improvement of GERD.</br> <b><br>Conclusions:</b> Revisional OAGB seems to be a good alternative after a failed SG in terms of obesity-related disease recurrence, not of weight regain. Long-term follow-up revealed that only a third of patients achieved successful weight loss. When proposing revisional OAGB, the risk of complications - mainly anemia and the possibility of de novo GERD should be considered.</br>.

Long Biliopancreatic Limb Roux-En-Y Gastric Bypass Versus One-Anastomosis Gastric Bypass: a Randomized Controlled Study

BACKGROUND

Roux-en-Y gastric bypass (RYGB) is the gold standard in bariatric surgery. The one-anastomosis gastric bypass (OAGB) procedure, first introduced by Dr. Rutledge, has demonstrated a 25% greater weight loss efficiency than the traditional Roux-en-Y gastric bypass (RYGB) procedure due to the substantially longer biliopancreatic limb (BPL).

AIM OF THE STUDY

The current work aimed to compare the outcomes of OAGB and long BPL RYGB regarding weight loss and comorbidity resolution.

PATIENTS AND METHODS

This randomized controlled trial was done at our institution between September 2019 and January 2021. Patients who were candidates for bariatric surgery were randomly and equally allocated to two groups. Group A underwent OAGB, while group B underwent long BPL RYGB. Patients were followed up for 6 months postoperatively.

RESULTS

This study included 62 patients equally allocated to OAGB or long BPL RYGB, with no dropouts during follow-up. At 6 months, there was no statistically significant difference between the two groups regarding postoperative BMI (P = 0.313) and the EBWL (P = 0.238). There was comparable remission of diabetes mellitus (P = 0.708), hypertension (P = 0.999), OSA (P = 0.999), joint pain (P = 0.999), and low back pain (P = 0.999). Seven patients in the OAGB group experienced reflux symptoms (P = 0.011), which were managed by proton pump inhibitors.

CONCLUSION

Extending the BPL in RYGB provides weight loss and comorbidity remission comparable to that of OAGB. Some OAGB-related reflux cases remain a concern. However, they were sufficiently controlled with PPIs. Due to OAGB superior technical simplicity, long BPL RYGB should be preserved for cases whom are more risky for bile reflux.

Remission of Type 2 Diabetes Mellitus (T2DM) after Sleeve Gastrectomy (SG), One-Anastomosis Gastric Bypass (OAGB), and Roux-en-Y Gastric Bypass (RYGB): A Systematic Review

Background and Objectives: The three most widely performed bariatric surgeries are Roux-en-Y gastric bypass (RYGB), sleeve gastrectomy (SG), and one-anastomosis gastric bypass (OAGB). Aside from the benefits of weight loss, current findings suggest that these procedures can also induce remission of T2DM (type 2 diabetes mellitus). There are limited data that directly compare these three procedures. This study aims to compare the short-term and long-term remission of T2DM after RYGB, SG, and OAGB. Materials and Methods: Three databases (Embase, PubMed, and Cochrane) were searched for randomised controlled trials, prospective studies, and retrospective studies that compared the effects of RYGB, SG, and OAGB on T2DM remission. Studies published between 2001 and 2022 were analysed. Only patients with T2DM and who had primary bariatric surgery were included. Results: After applying the inclusion and exclusion criteria, seven articles were included in the review. It was found that all three procedures had comparable T2DM remission. RYGB was noted to have the highest complication rate when compared to SG and OAGB. Importantly, it was noted that other predictive factors such as age, duration of diabetes, baseline HbA1c, BMI, and use of antidiabetic medication play a crucial role in T2DM remission. Conclusions: This systematic literature review confirms the existing data that all three bariatric surgeries induce remission of T2DM. Increasing in popularity, OAGB had comparable outcomes to RYGB and SG in inducing T2DM remission. In addition to the choice of bariatric surgery, there are other independent predictive factors that have an impact on T2DM remission. Further studies with larger sample sizes, longer follow-up periods, and studies that control confounding factors are required in this field.

OAGB with shortened excluded ileal loop as an effective treatment for type 2 diabetes mellitus in the cases of Caucasian men and women with obesity of the first degree (BMI 30-35 kg/m2)

INTRODUCTION

The aim of the study is to assess the effect of shortening the excluded loop of the small intestine to 150 cm on the effectiveness of one anastomosis gastric bypass (OAGB) in remission of type 2 diabetes with Io obesity.

MATERIAL AND METHODS

The study included 25 patients with a body mass index (BMI) 30-35 kg/m2, with a diagnosis of diabetes mellitus type 2 (T2DM), and undergoing OAGB with excluded 150 cm of the small intestine.

RESULTS

There were no deaths in the study group, bleeding during the postoperative period requiring reoperation, anastomotic leakage/leakage throught mechanical stitching. The mean a glycated haemoglobin (HbA1C) level 12 months after surgery was 6.16 ± 0.96%, corresponding to a 2.29 ± 3.3% decrease. In more than 85% of the patients taking insulin before surgery, the insulin was discontinued in the postoperative period. Additionally, the level of glycaemia was assessed in patients on the day of surgery (163 ± 58 mg/dl) and on the day of discharge from the hospital (4.7 ± 1.3 days)-it was lower by over 18% (133 ± 39.2 mg). Over the period of 12 months following OAGB, there was a reduction in the mean BMI value from 33.5 ± 2 to 25.5 ± 2.5 kg/m2 and improvement in lipid parameters and mean values of blood pressure.

CONCLUSION

OAGB with excluded 150 cm of the small intestine has beneficial effect on the remission of T2DM in patients with a BMI of 30-35kg/m2 and is associated with an acceptable level of complications. The achieved weight loss after surgery is satisfactory.

Comparing Patient Selection and 30-day Outcomes Between Single Anastomosis Gastric Bypass and Roux-en-Y Gastric Bypass: a Retrospective Cohort Study of 47,384 Patients

PURPOSE

Single anastomosis gastric bypass (SAGB) offers a novel bariatric procedure with increasing popularity. However, its adoption, patient selection, and short-term safety remain poorly characterized.

MATERIALS AND METHODS

The 2020 Metabolic and Bariatric Accreditation and Quality Improvement Program (MBSAQIP) was analyzed comparing SAGB to Roux-en-Y gastric bypass (RYGB). Bivariate analysis and multivariable logistic regression models compared difference between groups and factors associated with 30-day serious complications and mortality.

RESULTS

Overall, 47,384 patients were evaluated, with 1344 (2.8%) undergoing SAGB. SAGB patients had a higher BMI (45.2 ± 7.6 kg/m² vs 44.6 ± 7.9 kg/m², p = 0.006) and younger age (44.3 ± 12.1 years vs. 45.4 ± 11.5 years, p = 0.0008) than RYGB patients respectively. SAGB patients were less likely to have GERD (42.6% SAGB vs. 45.7% RYGB, p = 0.02), sleep apnea (37.8% SAGB vs. 41.1% RYGB, p = 0.02), and chronic steroid use (1.3% SAGB vs. 2.2% RYGB, p = 0.04). There were no significant difference in diabetes, hypertension, or dyslipidemia rates. Operative length for SAGB was significantly less than for RYGB (101 ± 53.7 min SAGB vs. 131.5 ± 63.3 min RYGB, p < 0.0001). SAGB was independently associated with decreased serious complications (4.7% vs. 8.4%, p < 0.0001) within 30 days compared to RYGB. Additionally, SAGB patients were less likely to experience reoperation (1.6% vs. 2.6%, p = 0.03), and readmission (2.2 vs. 5.8%, p < 0.0001) compared to RYGB respectively.

CONCLUSIONS

Compared to RYGB, patients undergoing SAGB were younger with marginally higher BMI. After adjusting for comorbidities, SAGB was associated with decreased odds of serious complications. Ongoing prospective studies analyzing long-term outcomes following SAGB remain needed.

The effects of laparoscopic Roux-en-Y gastric bypass and one-anastomosis gastric bypass on glycemic control and remission of type 2 diabetes mellitus: study protocol for a multi-center randomized controlled trial (the DIABAR-trial)

Background

Metabolic surgery induces rapid remission of type 2 diabetes mellitus (T2DM). There is a paucity of high level evidence comparing the efficacy of the laparoscopic Roux-en-Y gastric bypass (RYGB) and the laparoscopic one-anastomosis gastric bypass (OAGB) in glycemic control. Also, the mechanisms that drive the conversion of T2DM in severe obese subjects to euglycemia are poorly understood.

Methods

The DIABAR-trial is an open, multi-center, randomized controlled clinical trial with 10 years follow-up which will be performed in 220 severely obese patients, diagnosed with T2DM and treated with glucose-lowering agents. Patients will be randomized in a 1:1 ratio to undergo RYGB or OAGB. The primary outcome is glycemic control at 12 months follow-up. Secondary outcome measures are diverse and include weight loss, surgical complications, psychologic status and quality of life, dietary behavior, gastrointestinal symptoms, repetitive bloodwork to identify changes over time, glucose tolerance and insulin sensitivity as measured by mixed meal tests, remission of T2DM, presence of non-alcoholic fatty liver disease/non-alcoholic steatohepatitis in liver biopsy, oral and fecal microbiome, cardiovascular performance, composition of bile acids, and the tendency to develop gallstones.

Discussion

The DIABAR-trial is one of the few randomized controlled trials primarily aimed to evaluate the glycemic response after the RYGB and OAGB in severe obese patients diagnosed with T2DM. Secondary aims of the trial are to contribute to a deeper understanding of the mechanisms that drive the remission of T2DM in severe obese patients by identification of microbial, immunological, and metabolic markers for metabolic response and to compare complications and side effects of RYGB and OAGB.

Trial registration

ClinicalTrials.gov NCT03330756; date first registered: October 13, 2017.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-022-06762-3.

Experience of the First 100 OAGB in China: OAGB In Situ Technique

Background

One anastomosis gastric bypass (OAGB) is gradually accepted worldwide but still new in China.

Materials and Methods

Retrospective review of the patients who received OAGB in a new bariatric/metabolic surgical center in China and compared the data with a center of excellence in Taiwan. All in-patient and outpatient follow-up data were analyzed. The main outcome measures were (1) operation risk (2) weight loss (3) diabetes remission.

Results

Between August 2019 and October 2021, 100 consecutive patients who received OAGB in situ in China and 225 patients who received OAGB with the same technique were recruited from Taiwan. Taiwan patients were older (39.2 ± 10.6 vs. 33.3 ± 8.8 years old, p < 0.001), and to have more diabetes (32.4% vs. 20.0%, p = 0.022) comparing to the patients of China. Operation time was significantly longer for Taiwan patients (172.4 ± 36.9 vs. 128.5 ± 29.8, p < 0.001). Taiwan patients lost more blood during the operation (35.5 ± 25.2 vs. 22.4 ± 15.6, p < 0.001) but patients in China need more time to postoperative flatus passage (1.3 ± 0.5 vs. 2.0 ± 0.5, p < 0.001). There was no major surgical complication in this study, minor complication rates were similar low for both groups (1.0% vs. 1.8%, p = 0.891). At 1 year after surgery, %TWL and %EWL of both centers were similar (33.9 ± 7.43% vs. 32.6 ± 11.2%, p = 0.91; 81.9 vs. 19.8 vs. 85.4 ± 13.2, p = 0.798). T2DM remission (HbA1c < 6.5%) was 100% for patients of China and 95.9% for patients of Taiwan (p = 0.836).

Conclusions

OAGB in situ is a safe and effective bariatric/metabolic surgery. With proper training and proctorship, these results are reproduceable in a new bariatric/metabolic surgical center in China.

Graphical abstract

Closed loop small bowel obstruction due to herniation through silastic ring after bariatric surgery

Bariatric surgery is an effective treatment for obesity and obesity-related complications. Weight regain after surgery plagues all methods of bariatric procedures including the minigastric bypass. The use of a 'silastic ring' around the gastric pouch has been shown to reduce weight regain. We present here a very rare complication of silastic ring use, in which a loop of small bowel had herniated through the ring and produced a closed loop small bowel obstruction. The patient was successfully treated with an emergency laparotomy to resect the silastic ring and release the herniated bowel. This case highlights the hernia risk that silastic rings pose and cautions careful consideration before their use.

Probiotics for gallstones prevention in bariatric surgery patients: A prospective randomized trial

BACKGROUND

Gall stone disease was known to increase after bariatric surgery. Ursodeoxycholic acid (UDCA) might reduce the gallstone formation rate after bariatric surgery. However, other option for gallstone prevention was unclear. We reported the result of a randomized trial comparing the gallstone prevention efficacy of probiotics and digestive enzyme versus UDCA.

METHODS

This prospective, randomized trial was held in an institute of Taiwan. Patients were eligible for inclusion if their body-mass index (BMI) was 32.5 kg/m2 or higher with the presence of comorbidity, or 27.5 kg/mw or higher with not-well controlled type 2 diabetes, and were aged 18-65 years. Participant were randomized assigned (1:1:1) to probiotic, digestive enzyme or UDCA. The primary endpoint was assessed in the incidence of gallstone disease at 6 months after surgery. This study is registered with ClinicalTrials.gov. number NCT03247101, and is now completed.

RESULTS

From January 2016 to December 2018, of 186 patients screened for eligibility, 152 were randomly assigned to probiotic (52) or digestive enzyme (52) or UDCA (52). In the per-protocol population, mean age was 35.9 years (SD 10.6), mean BMI was 40.3 kg/m² (SD 6.9), 57(58.2%) were female. After 6 months, the incidence of gall bladder diseased was 15.2%, in the probiotics group, 17.6% in UDCA group and 29.1% in digestive enzyme groups, confirming non-inferiority of probiotic (p = 0.38). Female gender was identified as a risk factor for gall bladder disease after bariatric surgery (odds ratio = 4.61, 95% confidence interval = 1.05, 20.3, p = 0.04). The poor drug compliance rate was 19.5%, 22.7% and 26.2% in probiotics, UDCA and digestive enzyme group respectively. UDCA group had a higher drug adverse effect than probiotic group (15.9% vs. 2.4%, p = 0.03).

CONCLUSION

Probiotic is not inferior to UDCA regarding gall bladder disease prevention after bariatric surgery at 6 months.

Effect of Biliopancreatic Limb Length on Weight Loss, Postoperative Complications, and Remission of Comorbidities in One Anastomosis Gastric Bypass: a Systematic Review and Meta-analysis

Aimed to evaluate the effects of biliopancreatic limb (BPL) length on weight loss, postoperative complications, and remission of comorbidities in OAGB.. An extensive search was conducted in PubMed, Scopus, EMBASE, and Google Scholar databases to find related OAGB articles. Both BPL length < 200 cm (by - 17.79, 95% CI - 19.23, - 16.34) and BPL length ≥ 200 cm (by - 14.93, 95% CI - 15.66, - 14.20) significantly decreased BMI. Regarding the effect of BPL length on comorbidities and postoperative complications, it was shown that BPL length < 200 cm is safer and more effective. Therefore, standardization of BPL length < 200 cm is suggested. Bypassing ≥ 200 cm of the small bowel does not ameliorate weight loss or resolve comorbidities significantly, and it is related to more frequent postoperative complications and nutritional deficiencies. Registration number in PROSPERO: PROSPERO 2021 CRD42021225499.

Laparoscopic Banded One Anastomosis Gastric Bypass: A Single-Center Series

INTRODUCTION

Laparoscopic one anastomosis gastric bypass (LOAGB) is a relatively new procedure for the treatment of morbid obesity and related comorbidities. On average, this procedure results in good postoperative weight loss with a low complication rate. Recent publications suggest that dumping syndrome and weight regain might be reduced by placing a silicone ring over the gastric pouch during the procedure, so called laparoscopic banded one anastomosis gastric bypass (LBOAGB).

METHODS

86 patients undergoing LBOAGB between 2018 and 2020 were enrolled in this retrospective study. Hospital records were used to assess weight loss, comorbidity resolution, and any complications either in the short or medium term.

RESULTS

54 Female and 32 male patients were included with a mean age of 43 years (25-64), preoperative body mass index of 42 kg/m² (35-49), and preoperative weight of 114 kg (86-162). Thirty-four patients presented with type 2 diabetes (39.5%), 42 patients (49%) diagnosed with hypertension, 24 presented with OSAS (28%), and 21 (24%) hypercholesterolaemia patients were included. In total, 36 patients were diagnosed with multiple comorbidities. The operative data showed an average operative time of 48 minutes with 3.4% of patients suffering from early (minor) complications and 2.3% with a late (minor) complication. One patient required reoperation due to intra-abdominal bleeding. The median length of hospital stay was 2.5 days. Median follow-up was 18 months (5-36). In that period, no patient required ring removal or conversion to Roux-en-Y gastric bypass surgery. Food intolerance/vomiting was present in 1 patient (1.1%), bile reflux was present in 1 patient (1.1%), and no stomal ulcers were observed. Mean % excess weight loss at 12 and 24 months was 72% and 80%, respectively. Fifty-two out of 86 patients (60%) had a complete resolution of comorbidities. A CONUT score >2 (mild malnutrition) was found in 40% of patients, while a CONUT score 0-1 was found in 60% of patients.

CONCLUSION

LBOAGB shows promising results in terms of safety and efficacy in the short term. Further prospective studies will be required to evaluate the consistency of the results in the long term.

Bariatric Surgery and Liver Disease: General Considerations and Role of the Gut-Liver Axis

Weight loss is a therapeutic solution for many metabolic disorders, such as obesity and its complications. Bariatric surgery aims to achieve lasting weight loss in all patients who have failed after multiple dietary attempts. Among its many benefits, it has been associated with the regression of non-alcoholic fatty liver disease (NAFLD), which is often associated with obesity, with evidence of substantial improvement in tissue inflammation and fibrosis. These benefits are mediated not only by weight loss, but also by favorable changes in systemic inflammation and in the composition of the gut microbiota. Changes in microbial metabolites such as short-chain fatty acids (SCFAs), capable of acting as endocrine mediators, and bile acids (BAs) as well as modifications of the gut-brain axis, are among the involved mechanisms. However, not all bariatric surgeries show beneficial effects on the liver; those leading to malabsorption can cause liver failure or a marked worsening of fibrosis and the development of cirrhosis. Nevertheless, there are still many unclear aspects, including the extent of the benefits and the magnitude of the risks of bariatric surgery in cirrhotic patients. In addition, the usefulness and the safety of these procedures in patients who are candidates to or who have undergone liver transplant need solid supporting evidence. This paper aims to review literature data on the use of bariatric surgery in the setting of chronic liver disease.

Nutritional Assessment and Preparation for Adult Bariatric Surgery Candidates: Clinical Practice

Bariatric surgery (BS) has proven to be highly efficacious in the treatment of obesity and its comorbidities. However, careful patient selection is critical for its success. Thus, patients should undergo medical, behavioral, and nutritional assessment by a multidisciplinary team. From the nutritional point of view, BS candidates should undergo nutritional assessment, preparation, and education by a registered dietitian in the preoperative period. Currently, detailed specified and comprehensive information on these topics is lacking. The present narrative review aimed to summarize the available literature concerning both the preoperative nutritional assessment components and the preoperative nutritional preparation and education components of patients planning to undergo BS. Current literature indicates that proper management before BS should include a comprehensive nutritional assessment, in which it is advisable to perform a clinical interview to assess patients' medical background, weight management history, eating patterns and pathologies, oral health, physical activity habits, nutritional status, supplementation usage, BS knowledge, surgery expectations and anthropometric measurements. Nutritional preparation and educational strategies should include an individualized preoperative weight-loss nutrition program, improvement of glycemic control, micronutrients deficiencies correction, eating and lifestyle habits adaptation, physical activity initiation, and strengthening knowledge on obesity and BS. At this stage, more well-designed intervention and long-term cohort studies are needed in order to formulate uniform evidence-based nutritional guidelines for patients who plan to undergo BS, including populations at higher nutritional risk. Moreover, postoperative outcomes of presurgical nutritional intervention programs should be studied.

Long-Term Efficacy of Bariatric Surgery for the Treatment of Super-Obesity: Comparison of SG, RYGB, and OAGB

BACKGROUND

The most appropriate procedure for the treatment of super obesity (BMI > 50 kg/m²) is unknown. We aimed to evaluate the safety, long-term (> 5 years) weight loss, and adverse events between three commonly performed procedures, sleeve gastrectomy (SG), Roux-en-Y gastric bypass (RYGB), and one anastomosis gastric bypass (OAGB) in super-obese patients.

METHODS

Between January 2002 and December 2015, 498 successive patients with super morbid obesity (BMI > 50), who underwent SG or RYGB or OAGB, were recruited. Surgical outcome, weight loss, resolution of co-morbidities, and late complications were followed and compared between the 3 groups. All data derived from a prospective bariatric database and a retrospective analysis was conducted.

RESULTS

The average patient age was 32.1 ± 10.4 years, with a mean body mass index (BMI) of 56.0 ± 6.7 kg/m². Of them, 190 (38.9%) underwent SG, 62 (12.4%) RYGB, and 246 (49.4%) OAGB. There was no difference in basic characters between the 3 groups except SG had fewer diabetic patients. RYGB group had higher intraoperative blood loss, longer operating time, and hospital stay than the other 2 groups. RYGB had a higher 30-days post-operative major complication rate (4.8%) than SG (0.5%) and OAGB (0.8%). The follow-up rate at 1 and 5 years was 89.4% and 52.0%. At post-operative 5 years, OAGB had a higher total weight loss (40.8%) than SG (35.1%), but not RYGB (37.2%). SG had a lower remission rate in dyslipidemia comparing to OAGB and RYGB, but T2DM remission rate was no different between the groups. The overall revision rate is 5.4% (27/498) of the whole group, and SG had a lower revision rate (2.6%) than RYGB (8.1%) and OAGB (6.9%).

CONCLUSION

SG is an effective and durable primary bariatric procedure for the treatment of super obesity and metabolic disorders. OAGB had a similar operation risk to SG but resulted in a better weight loss than SG.

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.

Biliopancreatic Limb Length in One Anastomosis Gastric Bypass: Which Is the Best?

BACKGROUND

The use of one anastomosis gastric bypass (OAGB) is rapidly spreading. Concerns about biliary reflux and malabsorption with consequent nutritional deficits exist, so studies on biliopancreatic limb (BPL) adequate length in OAGB are required to balance excess weight loss in percentage (% EWL), resolution of comorbidities, and nutritional deficit. The purpose was to evaluate, at 2 years after OAGB, the effects of BPL length on weight loss, resolution of comorbidity, and nutritional deficiencies in patients.

METHODS

From January 2015 to January 2017, 180 patients were collected into three groups based BPL length: group A, 150 cm; group B, 180 cm; and group C, 200 cm. Aims were to compare %EWL, co-morbidity resolution rates, nutritional parameters, and morbidity/mortality in the three groups.

RESULTS

The total number of patients was 180: 60 for each group. One hundred seventy-two (95%) patients attended the 1-year follow-up (group A = 58; group B = 58, group C = 56). One hundred fifty-seven (87%) patients attended the 2-year follow-up (group A = 52 (87%); group B = 53 (88%); group C = 52 (87%)). There was no statistically significant difference in %EWL, %TWL, T2DM, and hypertension resolution rates among the groups. About vitamin deficiency, differences were not statistically significant. Iron and ferritin deficiency rate were statistically significant only between A and C groups.

CONCLUSIONS

According to our evidence, standardization of BPL length shorter than 200 cm is suggested, potentially minimizing malnutrition-related outcomes. Our study seems to show that a BPL of 150-180 cm is safe and effective in terms of EWL and comorbidity improvement with low malnutrition effects even in BMI > 50.

Bile reflux after one anastomosis gastric bypass surgery: A review study

Background

Recently the performance rate of one anastomosis gastric bypass (OAGB) bariatric surgery has increased. Bile reflux is on of common considered complication of OAGB challenging surgeon.

Methods

We searched English full text with keyword "bile reflux" AND "OAGB" OR "one anastomosis gastric bypass" OR "SAGB" OR "single anastomosis gastric bypass" that published from January 1st, 2000 to December 31st, 2020 in PubMed, EMBASE, Google scholar and Cochrane Library. We included prospective or retrospective systematic review, review, clinical, and meta-analysis human article that its full text was available and focused on bile reflux after OAGB/SAGB as the fundamental performed bariatric surgery.

Results

A total of 1259 articles were analyzed, of which 5 were included. Analysis of number articles by year revealed that 2019 and 2020 was the highest number of published articles (n = 232; 68%). Study type analysis revealed that review studies and clinical research (n = 62; 18.2%) were the most frequent study types. Reported data on bile reflux after OAGB had diversity. Implicitly, postoperative incidence of bile reflux differed from 7.8 to 55.5%. General consensus was not existed among authors to consider the OAGB as the first suspect leading to postoperative bile reflux among other bariatric surgery types.

Conclusion

Although surgeons prefer to conduct OAGB procedure because of its easier surgical approach needing just one anastomosis formation it is not virtually clear that is the procedure costly benefitted regarding bile reflux outcomes.

Long-term outcomes of metabolic surgery in overweight and obese patients with type 2 diabetes in Asia

AIM

To assess the outcomes of metabolic surgery in overweight and obese patients in Asia with type 2 diabetes (T2D).

MATERIALS AND METHODS

The treatment outcomes of 1999 patients from the Asian Diabetes Surgery Summit database were analysed. The changes in treatment effects across time were assessed with respect to the surgical procedures performed by using generalized estimating equations.

RESULTS

The most commonly performed procedure was the single-anastomosis gastric bypass (32.6%). Weight (from 106.2 ± 25.1 to 77.9 ± 18.8 kg), body mass index (BMI; from 38.7 ± 7.9 to 28.5 ± 5.9 kg/m² ), blood sugar (from 9.3 ± 4.1 to 5.7 ± 1.8 mmol/L) and HbA1c (from 8.4% ± 1.8% to 6.0% ± 1.1%) significantly improved from baseline to 1 year (P < .001) and remained stable at 5 years (weight, 86.3 ± 23.3 kg; BMI, 31.7 ± 7.9 kg/m² ; blood sugar, 5.8 ± 1.8 mmol/L, and HbA1c, 6.4% ± 1.2%; all P < .001 vs. baseline). Blood pressure and most lipid disorders also improved significantly. Of the treatment procedures, single-anastomosis gastric bypass had the most satisfactory outcomes with statistical significance for most disorders, whereas adjustable gastric banding displayed the least satisfactory outcomes.

CONCLUSIONS

Metabolic surgery remarkably improved body weight, T2D and other metabolic disorders in Asian patients. However, the efficacy of individual procedures varied substantially.

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 versus Roux-en-Y gastric bypass: a 30-day follow-up review

BACKGROUND

One anastomosis gastric bypass (OAGB) type procedures have been widely adopted outside the United States. International experience of OAGB commonly suggests improved early postoperative safety with OAGB over Roux-en-Y gastric bypass (RYGB). This study aims to report on the early experience with OAGB in Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP) accredited centers, and compare with RYGB in terms of complication rates.

METHODS

The MBSAQIP public use files from 2015 to 2018 were used to identify adult patients who underwent primary OAGB and RYGB. Propensity score analysis was used to estimate the marginal population-average differences between OAGB and RYGB patients. Based on the matched samples, McNemar's tests and Wilcoxon signed rank test were carried out for binary and continuous outcomes. P-value < 0.05 was considered statistically significant.

RESULTS

Propensity score matching analysis resulted in 279 matched pairs for OAGB and RYGB. Twelve OAGB patients (4.3%) experienced a complication; 3 of them (1.1%) were diagnosed with anastomotic leaks. Compared to 14 (5%) of RYGB patients experiencing a complication; 5 (1.8%) were diagnosed with anastomotic leaks. Reintervention, reoperation and readmission rates for OAGB were 2.5%, 3.2% and 5%, compared to 1.8%, 1.8%, and 3.2% for RYGB.

DISCUSSION

Our study supports previous data that suggests OAGB has a similar early safety profile compared to RYGB and perioperative risks of OAGB should not be of a concern regarding its adoption. Conversely, OAGB does not seem to be associated with an improved safety profile over RYGB.

Twenty years' experience of laparoscopic 1-anastomosis gastric bypass: surgical risk and long-term results

BACKGROUND

Laparoscopic 1- (single-) anastomosis gastric bypass (OAGB) was developed as a simplified technique of Roux-en-Y gastric bypass (RYGB), but super long-term data are lacking.

OBJECTIVES

To evaluate the risks and long-term results of OAGB over a period of 20 years.

SETTING

Tertiary teaching hospital.

METHODS

A total of 2223 patients underwent OAGB from 2001 to 2020; the mean age was 35.3 ± 11.4 years (range, 14-71 yr), 70.2% were female, and the mean body mass index was 40.2 ± 11.9 kg/m². All data were kept in a prospective bariatric database. Patients were divided into 4 groups, based on the 5-year period in which their surgery was performed, and a retrospective analysis was conducted.

RESULTS

The means for operating time, intraoperative blood loss, and length of hospital stay after OAGB were 131.9 ± 40.1 minutes, 38.5 ± 30.7 mL, and 4.5 ± 4.0 days, respectively. There were 27 patients (1.2%) with 30-day postoperative major complications overall, but the group rate decreased to .4% in the last 5-year period. At postoperative years 5, 10, and 15, the percentages of total weight loss were 31.9%, 29.6%, and 29.5%, respectively, and the percentages of excess weight loss were 77.2%, 68.4%, and 65.5%, respectively. Among 739 patients (33.2%) with type 2 diabetes (T2D), the rates of complete remission (glycated hemoglobin < 60%) at 5, 10, and 15 years were 67.3%, 73.8%, and 66.7%, respectively. The weight loss and antimetabolic effects were similar in each 5-year period, but a significant malnutrition effect was observed. A total of 113 (5.1%) patients needed revision surgery at follow-up, due to malnutrition (n = 51), weight regain (n = 24), acid or bile reflux (n = 22), marginal ulcer (n = 8), ileus (n = 3), and other causes (n = 5). At 15 years, the overall revision rate was 11.9% (27/226), and 80% of the patients were very satisfied with their procedures.

CONCLUSION

Our results showed that OAGB is a safe and durable primary bariatric procedure, with sustained weight loss and a high resolution of T2D up to 20 years post surgery in Taiwan, although malnutrition is a major side effect.

One Anastomosis Gastric Bypass for the Treatment of Type 2 Diabetes: Long-Term Results and Recurrence

BACKGROUND

Bariatric/metabolic surgery has been incorporated into the therapeutic treatment of type 2 diabetes mellitus (T2DM). Among many bariatric/metabolic procedures, one anastomosis gastric bypass (OAGB) is one of the most effective procedures but long-term data about T2DM recurrence after OAGB are lacking.

METHODS

Outcomes of 134 patients who had undergone OAGB for the treatment of T2DM with long-term (5 years) follow-up were assessed in a retrospective cohort study. The remission of T2DM after OAGB surgery was evaluated in different groups using a scoring system composed of the age, BMI, C-peptide level, duration of T2DM (ABCD score), and percent of total weight loss (%TWL).

RESULTS

The %TWL and percent of excess weight loss (%EWL) of the OAGB patients at 5 years after surgery were 29.2 (10.6) and 72.1(27.5), respectively. The mean BMI decreased from 39.5(7.9) to 27.6(5.3) kg/m² and mean glycated hemoglobin A1C (HbA1c) decreased from 8.9 to 5.9% in OAGB patients at 5 years after OAGB. The complete T2DM remission rate of OAGB was 76.1% at 1 year and 64.2% at 5 years after surgery. Forty-one (57.8%) out of 71 patients who completed a 10-year follow-up remained in complete T2DM remission. The T2DM recurrence rate of OAGB patients was 15.7% at 5 years after surgery.

CONCLUSIONS

OAGB is highly effective in inducing T2DM remission but a significant number of patients will still have T2DM recurrence. To select patient with an ABCD score > 5 and maintaining a weight loss greater than 30% is important for durable T2DM remission after OAGB.

Computational Tools for the Reliability Assessment and the Engineering Design of Procedures and Devices in Bariatric Surgery

Obesity is one of the main health concerns worldwide. Bariatric Surgery (BS) is the gold standard treatment for severe obesity. Nevertheless, unsatisfactory weight loss and complications can occur. The efficacy of BS is mainly defined on experiential bases; therefore, a more rational approach is required. The here reported activities aim to show the strength of experimental and computational biomechanics in evaluating stomach functionality depending on bariatric procedure. The experimental activities consisted in insufflation tests on samples of swine stomach to assess the pressure-volume behaviour both in pre- and post-surgical configurations. The investigation pertained to two main bariatric procedures: adjustable gastric banding (AGB) and laparoscopic sleeve gastrectomy (LSG). Subsequently, a computational model of the stomach was exploited to validate and to integrate results from experimental activities, as well as to broad the investigation to a wider scenario of surgical procedures and techniques. Furthermore, the computational approach allowed analysing stress and strain fields within stomach tissues because of food ingestion. Such fields elicit mechanical stimulation of gastric receptors, contributing to release satiety signals. Pressure-volume curves assessed stomach capacity and stiffness according to the surgical procedure. Both AGB and LSG proved to reduce stomach capacity and to increase stiffness, with markedly greater effect for LSG. At an internal pressure of 5 kPa, outcomes showed that in pre-surgical configuration the inflated volume was about 1000 mL, after AGB the inflated volume was slightly lower, while after LSG it fell significantly, reaching 100 mL. Computational modelling techniques showed the influence of bariatric intervention on mechanical stimulation of gastric receptors due to food ingestion. AGB markedly enhanced the mechanical stimulation within the fundus region, while LSG significantly reduced stress and strain intensities. Further computational investigations revealed the potentialities of hybrid endoscopic procedures to induce both reduction of stomach capacity and enhancement of gastric receptors mechanical stimulation. In conclusion, biomechanics proved to be useful for the investigation of BS effects. Future exploitations of the biomechanical methods may largely improve BS reliability, efficacy and penetration rate.

Variation in Small Bowel Length and Its Influence on the Outcomes of Sleeve Gastrectomy

PURPOSE

Small bowel length is drawing attention in the development of gastrointestinal bariatric/metabolic surgery, but the importance of the length of the small bowel in bariatric/metabolic is not clear. The present study was conducted to investigate variations in small bowel length and their clinical significance in patients undergoing laparoscopic sleeve gastrectomy (LSG).

MATERIALS AND METHODS

Small bowel length was measured in 620 patients diagnosed with obesity who underwent LSG between March 2014 and August 2018. Prospectively obtained demographic and clinical data were investigated, focusing on the association between small bowel length and weight loss.

RESULTS

Small bowel length varied widely among patients (mean 739.8 + 115.7 cm, range 380-1050 cm). Linear regression analysis revealed a significant association between small bowel length and body height, body weight, waist circumference, and serum levels of low-density lipoprotein cholesterol, hemoglobin, C-peptide, glycated hemoglobin (A1C), and gamma-glutamyl transferase (r-GT). Multivariate analysis confirmed that body height and serum A1C% levels independently predicted small bowel length in bariatric patients, strongly with body height (p < 0.001) but weakly with A1C%(p = 0.021). One-year follow-up rate was 75.3% (467/620), and small bowel length did not influence weight loss or the reduction of obesity related cardiovascular risk factors after LSG.

CONCLUSION

In this study, small bowel length varied widely among bariatric patients and was strongly associated with body height and weakly with serum A1C levels. Small bowel length has no significant role in weight loss or the resolution of cardiovascular risk factors after LSG.

Randomized Controlled Trial of One Anastomosis Gastric Bypass Versus Roux-En-Y Gastric Bypass for Obesity: Comparison of the YOMEGA and Taiwan Studies

BACKGROUND

The YOMEGA study (Y-study) was a randomized trial comparing one anastomosis gastric bypass (OAGB) and Roux-en-Y gastric bypass (RYGB). Here, we aim to compare the Y-study and our pioneer trial from Taiwan (T-study).

METHODS

Data from the Y-study and the T-study were collected and compared.

RESULTS

The Y-study recruited 234 patients with a mean body mass index (BMI) of 43.9 and age of 43.5 years. The T-study recruited 80 patients with a similar mean BMI of 44.3 and mean age of 31.4 years. The studies had similar findings including (1) OAGB is easier and possibly safer procedure than RYGB. Both studies showed that OAGB had a shorter operation time than RYGB, but a lower surgical complication rate was only demonstrated in T-study. (2) Both procedures have similar weight loss but OAGB features better glycemic control than RYGB. Weight loss at 2 years after surgery was similar between two procedures, but OAGB reduced HbA1c to a greater degree than RYGB at 2 years in Y-study (- 2.3% vs. - 1.3%; p = 0.025). The resolution of the metabolic syndrome was 100% for both groups in the T-study. (3) OAGB carried a higher risk of malnutrition. OAGB had more malabsorptive problems with a lower hemoglobin level than RYGB at 2 years after surgery. Adverse malnutrition events occurred in nine (7.8%) OAGB patients in the Y-study. Four (3.4%) patients of OAGB received revision surgery in Y-study but none in T-study. (4) Bile reflux was noted in OAGB patients but did not influence quality of life or revision rate. Y-study found that bile in the gastric pouch was present in 16% of patients in the OAGB group versus none in the RYGB, but no inter-group difference in quality of life was detected. There was a trend for RYGB patients to experience more abdominal pain than OAGB.

CONCLUSIONS

Both studies showed that OAGB is a technically easier procedure and features better glycemic control than RYGB, but has a mal-absorptive effect. However, the bile reflux and abdominal pain controversies persisted.

Conventional Versus Distal Laparoscopic One-Anastomosis Gastric Bypass: a Randomized Controlled Trial with 1-Year Follow-up

BACKGROUND

There is no consensus on the ideal small bowel length that should be bypassed in laparoscopic one-anastomosis gastric bypass (OAGB). This study aimed to compare the safety and efficacy of conventional versus distal techniques of laparoscopic OAGB.

METHODS

This randomized controlled trial involved 60 adults with morbid obesity scheduled for laparoscopic OAGB randomly assigned to one of the two techniques; conventional technique (fixed anastomosis 200 cm from the ligament of Treitz) and distal technique (anastomosis 400 cm from the ileocecal valve). Total small bowel length (TSBL) was measured in all cases. Quality of life was assessed using the Gastrointestinal Quality of Life Index (GIQLI). Outcome measures were excess body weight loss percentage (EBWL%), resolution of associated comorbidities, frequency of nutritional deficiencies, and quality of life.

RESULTS

No patients were lost to follow-up. The two groups were comparable in TSBL, EBWL%, and complete resolution of comorbidities up to 12 months. The percentage of afferent loop length to TSBL was significantly higher in the distal group (p < 0.001) but was not correlated with EBWL%. The levels of hemoglobin, cholesterol, triglycerides, iron, and albumin were significantly lower and parathormone hormone was higher in the distal group. The GIQLI score was significantly higher in the conventional group during follow-up.

CONCLUSION

OAGB achieves optimum results when the afferent loop length is 200 cm; bypassing more than 200 cm does not improve weight loss or comorbidity resolution. Measuring TSBL is recommended to avoid excessive small bowel shortening that increases the risk of nutritional consequences.

A 5-Year Follow-up in Children and Adolescents Undergoing One-Anastomosis Gastric Bypass (OAGB) at a European IFSO Excellence Center (EAC-BS)

BACKGROUND

The children and adolescent population with obesity has increased worldwide, both in developing areas and in developed countries. Consequently, the prevalence of morbid obesity among this population has also increased, leading to an exponential growth of bariatric approaches in this population. Many surgeons fear eventual nutritional sequelae after malabsorptive approaches and prefer restrictive or mixed procedures.

METHODS

A retrospective review of all the morbidly obese patients between 13 and 19 years, undergoing a one-anastomosis gastric bypass (OAGB) as bariatric procedure between 2004 and 2012, was performed.

RESULTS

A total of 39 patients were included, 8 males (20.5%) and 31 females (79.5%), with a mean age of 17.8 ± 2 years (range 13-19 years). Mean preoperative weight was 114.3 ± 20.4 kg and mean BMI 42.2 ± 5.9 kg/m². Preoperative comorbidities include only type 2 diabetes mellitus (T2DM) in 7.9% of the patients, hypertension in 10.3%, and dyslipidemia in 23.1%. Five years after surgery, mean BMI was 25.9 ± 5.3 kg/m² and total weight loss 32.1 ± 15.7%. Remission rate of T2DM, hypertension and dyslipidemia was 100%. All the patients received multivitamin and vitamin D supplementation. Anemia secondary to iron deficiency occurred in one female, requiring intravenous iron supplementation during 1 year and later on oral supplementation.

CONCLUSIONS

OAGB is a valid alternative for long-term weight loss and remission of comorbidities in childhood and adolescence. No cases of malnutrition or growth disorders were observed.

Weight Loss and Vomiting 1 Year After Banded Versus Non-banded One Anastomosis Gastric Bypass: a Prospective Randomized Trial

BACKGROUND

The weight loss outcomes after banded one-anastomosis gastric bypass (OAGB) remain to be determined.

OBJECTIVE

To compare weight loss and vomiting 1 year after banded versus non-banded OAGB.

METHODS

This is a prospective, open-label, randomized study, which evaluated 33 individuals with morbid obesity, which underwent banded (16 individuals) and non-banded OAGB (17 individuals) and were followed up for 12 months. Weight loss (percentages of total weight loss-%TWL-and excess weight loss-%EWL) and occurrence of vomiting were assessed and compared before surgery and after 6 and 12 months.

RESULTS

At baseline, there were no differences between groups in regard to age, gender, and body mass index (BMI). At 6 and 12 months post-op, and the overall mean %TWL regardless of band use was 22.4 ± 7% and 29 ± 6.9%, respectively, and the overall average %EWL regardless of band use was 66.8 ± 22.9% and 86.3 ± 24%, respectively. %TWL did not differ between the banded and non-banded groups at 6 (21.8 ± 6.8% vs. 23.1 ± 7.4%; p = 0.7) and 12 months post-op (27.5 ± 6.6% vs. 30.4 ± 7.1%; p = 0.3), as well as %EWL at 6 (67 ± 22.9% vs. 67.6 ± 23.6%; p = 0.6) and 12 months post-op (83.5 ± 24.4% vs. 89 ± 24.1%; p = 0.4). The occurrence of vomiting did not significantly differ between banded and non-banded OAGB at 6 (12.5% vs. 11.8%; p = 0.9) and 12 months post-op (12.5% vs. 5.9%; p = 0.5).

CONCLUSION

OAGB led to an overall satisfactory weight loss after 1 year, regardless of band use. Banded OAGB did not lead to neither significantly higher weight loss nor more vomiting than non-banded OAGB 1 year after surgery.

Short- and Mid-term Outcomes of 527 One Anastomosis Gastric Bypass/Mini-Gastric Bypass (OAGB/MGB) Operations: Retrospective Study

BACKGROUND

One anastomosis gastric bypass/mini-gastric bypass (OAGB/MGB) is considered an alternative option in metabolic and bariatric surgery. The aim of this study was to evaluate the safety, efficacy and postoperative challenges of OAGB/MGB as a new procedure.

METHODS

We performed 519 primary MGBs and 8 additional second-stage MGBs during 2014-2018. The data were collected from patients' notes as well as the surgeons' prospective data sheets. Two senior surgeons performed the operations. The ultimate primary measures were assessment of the safety and management of the complications. The secondary outcomes were excess weight loss and resolution of the comorbidities.

RESULTS

The type 2 diabetes mellitus (T2DM) remission rate was 83% and 70% over 1 and 3 years, respectively (HBA1C < 6.5%). Weight loss was 28-152 kg (SD 23.11). Excess weight loss ranged from 41 to 125%. Hypertension resolution was 61%, 58% and 58% in the first, second and third years, respectively. Ninety-nine per cent of sleep apnoea patients improved symptomatically and went off the continuous positive airway pressure (CPAP) machine. Two (0.37%) patients developed diarrhoea, cured by shortening the afferent biliopancreatic limb (BPL). Eight (1.5%) stomal ulcers were reported. Two patients (0.37%) developed deranged liver function, revised by shortening the BPL in one patient and a reversal in the second patient. The mean follow-up was 2.5 years. Mortality was zero.

CONCLUSIONS

This is the largest UK OAGB/MGB study to date showing safety and acceptable results for metabolic syndrome and obesity problems. OAGB/MGB revisional options are rectifying the morbidity and no mortality.

One Anastomosis Gastric Bypass Reconstitutes the Appropriate Profile of Serum Amino Acids in Patients with Morbid Obesity

Bariatric surgery leads to metabolic benefits in patients with obesity, but their mechanisms are not well understood. The appropriate composition of serum amino acids (AA) is important for sufficient supply of these components into various tissues and organs. Obesity leads to alterations in serum AA concentrations. The aim of this study was to examine the effect of one anastomosis gastric bypass (OAGB), a promising type of bariatric surgery, on serum AA concentrations, which were assayed by LC-MS in serum of 46 bariatric patients prior to and 6–9 months after OAGB, as well as in 30 lean control subjects. The results were analyzed by principle components analysis and metabolic pathway analysis. PCA analysis showed that OAGB led to normalization of serum AA concentrations of patients with obesity to a pattern similar to the control subjects, and the concentrations of essential AA remained decreased after OAGB. Changes of individual AA and their associated metabolic pathways were also presented. OAGB caused normalization of the AA profile, which may contribute to improvement of glucose homeostasis and reduction of cardiovascular risk. Considering decreased essential AA concentrations after OAGB, increased intake of high protein food should be recommended to the patients after this type of bariatric surgery.

THE ONE ANASTOMOSIS GASTRIC BYPASS TECHNIQUE: RESULTS AFTER ONE YEAR OF FOLLOW-UP

Background:

Obesity is a major health problem. One anastomosis-gastric bypass (OAGB) is a restrictive and malabsorptive weight loss surgery that carries the same characteristics of Roux-en-Y gastric bypass in its status as a weight loss mechanism; but, its results remain controversial.

Aim:

To describe the technique and outcomes of OAGB and its effects on weight loss and remission of comorbidities.

Methods:

Retrospective review of all patients who underwent OAGB procedure from January 2017 to January 2018. Patients’ baseline characteristics were recorded. The routine in follow-up were at 1, 3, 6 and 12 months.

Results:

A total of 51 patients underwent OAGB. The mean age was 43.8±9.3 years, mean weight was 125±31 and mean BMI was 55.8±12 kg/m². With regard to comorbidities, 64.7% had type 2 diabetes mellitus (T2DM), 43.1% systemic arterial hypertension (SAH) and 51% dyslipidemia. The BMI decreased for 48.4±1.3 to 31±4.4 at 12 months (p=0.0001) and we obtained an average decreased of 65% excess weight loss (EWL) at 12 months of follow-up. There was improvement in the values of total cholesterol (CT) (p=0.348); triglycerides (TGC) (p=0.0001); LDL (p=0.06), HDL (p=0.029) and A1C (p=0.405). Remission of T2DM al 12 months follow-up after surgery was 57% (p=0.124), remission of SAH 37% (p=0.040) and remission of dyslipidemia of 43% (p=0.967).

Conclusions:

OAGB is a commonly performed and safe procedure. Short term results appear promising; however, long-term follow-up is necessary to evaluate complications and possible nutritional effects.

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

INTRODUCTION

Obesity has experienced worldwide increase and surgery has become the treatment that has achieved the best results. Several techniques have been described; the most popular are vertical gastrectomy (GV) and the Roux-en-Y gastric bypass (RYGB). However, mini-gastric bypass/one anastomosis gastric bypass (MGB/OAGB) has gained popularity due to its simplicity and good results.

OBJECTIVE

To comparatively evaluate the results of MGB/OAGB with those of RYGB with 1-year follow-up.

METHODS

The paper presents a comparative case and control study of 100 patients that underwent MGB/OAGB surgery and another 100 with RYGB surgery, operated between 2008 and 2016. Patients were not submitted to revision surgery and had the following pre-operative variables: age 40.46 ± 12.4 vs. 39.43 ± 10.33 years; sex 64 and 54 women, 36 and 46 men; BMI 44.8 ± 12.06 and 45.29 ± 8.82 kg/m²; 50 and 54 cases with comorbidities, respectively, these being non-significant differences.

RESULTS

The surgical time was 69.01 ± 4.62 (OAGB) vs. 88.98 ± 3.44 min; the time of hospitalization was 2 days, reaching a BMI of 27.7 ± 7.85 and 29 ± 4.52 kg/m², with an excess weight loss 1 year after surgery of 89.4 vs. 85.9%, respectively. The morbidity rates are 9% for OAGB and 11% for the RYGB. There was a comorbidity resolution of 84.4 and 83.7% respectively, without mortality.

CONCLUSIONS

The results show the benefits of both techniques, OAGB being the easiest to perform and with less surgical time.

Incidence and Risk Factors for Mortality Following Bariatric Surgery: a Nationwide Registry Study

BACKGROUND

Although bariatric surgery (BS) is considered safe, concern remains regarding severe post-operative adverse events and mortality. Using a national BS registry, the aim of this study was to assess the incidence, etiologies, and risk factors for mortality following BS.

METHODS

Prospective data from the National Registry of Bariatric Surgery in Israel (NRBS) including age, gender, BMI, comorbidities, and surgical procedure information were collected for all patients who underwent BS in Israel between June 2013 and June 2016. The primary study outcome was the 3.5-year post-BS mortality rate, obtained by cross-referencing with the Israel population registry.

RESULTS

Of the 28,755 patients analyzed (67.3% females, mean age 42.0 ± 12.5 years, and preoperative BMI 42.14 ± 5.21 kg/m²), 76% underwent sleeve gastrectomy (SG), 99.1% of the surgeries were performed laparoscopically, and 50.8% of the surgeries were performed in private medical centers. Overall, 95 deaths occurred during the study period (146.9/100,000 person years). The 30-day rate of post-operative mortality was 0.04% (n = 12). Male gender (HR = 1.94, 95%CI 1.16-3.25), age (HR = 1.06, 95%CI 1.04-1.09), BMI (HR = 1.08, 95%CI 1.05-1.11), and depression (HR = 2.38, 95%CI 1.25-4.52) were independently associated with an increased risk of all-cause 3.5-year mortality, while married status (HR = 0.43, 95%CI 0.26-0.71) was associated with a decreased risk.

CONCLUSION

Mortality after BS is low. Nevertheless, a variety of risk factors including male gender, advanced age, unmarried status, higher BMI, and preoperative depressive disorder were associated with higher mortality rates. Special attention should be given to these "at-risk" BS patients.

Mini Gastric Bypass-One Anastomosis Gastric Bypass (MGB-OAGB)-IFSO Position Statement

PREAMBLE

The International Federation for the Surgery of Obesity and Metabolic Disorders (IFSO) has played an integral role in educating both the metabolic surgical and the medical community at large about the role of innovative and new surgical and/or endoscopic interventions in treating adiposity-based chronic diseases.The mini gastric bypass is also known as the one anastomosis gastric bypass. The IFSO has agreed that the standard nomenclature should be the mini gastric bypass-one anastomosis gastric bypass (MGB-OAGB). The IFSO commissioned a task force (Appendix 1) to determine if MGB-OAGB is an effective and safe procedure and if it should be considered a surgical option for the treatment of obesity and metabolic diseases.The following position statement is issued by the IFSO MGB-OAGB task force and approved by the IFSO Scientific Committee and Executive Board. This statement is based on current clinical knowledge, expert opinion, and published peer-reviewed scientific evidence. It will be reviewed in 2 years.

The Effect of Pre-Surgery Information Online Lecture on Nutrition Knowledge and Anxiety Among Bariatric Surgery Candidates

INTRODUCTION

Best practices for patient education in bariatric surgery (BS) remain undefined. The aims of this study were to evaluate the effect of an online lecture on nutrition knowledge, weight loss expectations, and anxiety among BS candidates and present a new tool to assess this knowledge before BS.

METHODS

An interventional non-randomized controlled trial on 200 BS candidates recruited while attending a pre-BS committee. The first 100 consecutive patients were assigned to the control group and the latter 100 consecutive patients to the intervention group and were instructed to watch an online lecture of 15-min 1-2 weeks prior to surgery. All participants completed a BS nutrition knowledge and the state-trait anxiety inventory (STAI) questionnaires at the pre-BS committee and once again at the pre-surgery clinic. Body mass index (BMI), comorbidities, surgery type, marital status, and number of dietitian sessions were obtained from medical records.

RESULTS

Data for paired study questionnaires scores were available for 128 patients (n = 69 and n = 59 for the control and intervention groups, respectively), with a mean age and BMI of 40.3 ± 11.4 years and 41.3 ± 4.9 kg/m², respectively. The BS nutrition knowledge and the state anxiety scores increased for both study groups at the pre-surgery clinic as compared to the pre-BS committee (P ≤ 0.028), but the improvement in the nutrition knowledge score was significantly higher for the intervention group (P = 0.030). No within or between-group differences were found for the trait anxiety items score. The "dream" and "realistic" weight goals were lower than the expected weight loss according to 70% excess weight loss (EWL) for both study groups at both time-points (P < 0.001 for all).

CONCLUSION

Education by an online lecture prior to the surgery improves BS nutrition knowledge, but not anxiety. ClinicalTrials.gov number: NCT02857647.

Measuring the small bowel length may decrease the incidence of malnutrition after laparoscopic one-anastomosis gastric bypass with tailored bypass limb

BACKGROUND

Laparoscopic one (single)-anastomosis gastric bypass (OAGB) is an effective and durable treatment for morbidly obese patients. However, the ideal length of the small bowel bypass remains controversial.

OBJECTIVES

The study aimed to report the clinical results of using a tailored bypass based on the total length of the small bowel.

SETTING

Academic medical center.

METHODS

Since 2005, we have performed OAGB with tailored limb according to preoperative body mass index. From July 2014, we modified our technique, measuring the whole small bowel length to keep the common channel at least 400-cm long. Data from 470 patients treated with the new technique (Group II) were compared with those of a matched group treated with tailored bypass only (Group I). The preoperative clinical data and outcomes were analyzed. All clinical data were prospectively collected and stored.

RESULTS

Both groups had similar clinical profiles at baseline. All procedures were completed laparoscopically. Group II had a significant longer operation time (161.9 versus 122.6 min; P < .001), but shorter hospital stay (2.9 versus 5.3 d; P < .001) and lower complication rate (.2% versus 1.5%; P = .002) than Group I. One year after surgery, the mean body mass index (27.4 versus 26.8 kg/m²; P = .244), percent total weight loss (32.0% versus 34.0%; P = .877), and diabetes remission rate (84.7% versus 84.1%; P = .876) were comparable between the 2 groups. However, Group II patients had a significantly lower incidence of anemia (5.9% versus 11.1%; P < .001), secondary hyperparathyroidism (21.7% versus 33.8%; P < .001) and hypoalbuminemia (1.5% versus 2.8%; P < .001) than did Group I.

CONCLUSION

Routine measurement of the whole bowel length to keep the common channel at least 400-cm long may reduce the incidence of malnutrition after OAGB with tailored limb bypass, without compromising efficacy in weight loss and diabetes resolution.

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.