Should Roux-en-Y gastric bypass biliopancreatic limb length be tailored to achieve improved diabetes outcomes?

Enhanced Total Weight Loss 2 Years Post-Roux-en-Y Gastric Bypass with Longer Biliopancreatic Limb

BACKGROUND

Despite widespread use of Roux-en-Y gastric bypass (RYGB), there are no standardized limb lengths in the United States.

METHODS

A multi-center retrospective cohort study was conducted from 2020 to 2023. Eligible patients who had undergone RYGB were divided into subgroups based on BP limb lengths: short (50-75 cm), intermediate (80-125 cm), and long (150-175 cm). Primary outcomes were total weight loss (TWL) and % TWL at 1 and 2 years. Secondary outcomes were post-operative BMI and % BMI change at 1 and 2 years, micronutrient deficiencies, hypothyroidism, acute kidney injury (AKI) requiring treatment, and remission in associated medical problems. Subgroups were compared using multivariate analysis.

RESULTS

Two hundred twenty-eight patients received a long BP limb, 194 patients received an intermediate BP limb, while 152 patients received a short BP limb. Primary outcomes TWL and % TWL were significantly different between the groups at 1 year: TWL and % TWL were greater in patients with long BP limbs. The difference between the long and short BP limb groups increased at the 2-year mark. Patients who had long BP limbs had higher rates of DM remission (12.3% vs 11.9% 6.6%), HTN (8.8% vs 5.7% vs 7.9%), GERD symptoms (14.5% vs 9.8% vs 5.3%), and OSA (8.8% vs 7.7% vs 5.3%). Vitamin A deficiency rates were higher in the long BP limb group.

CONCLUSIONS

The results suggest that longer BP limb lengths are conducive to TWL and overall treatment of obesity-related problems without severe rates of complications. Additional longer longitudinal studies are needed to assess the impact of long BP limbs on nutrition and weight loss in the long term.

Total Alimentary Limb Length Is Not Associated with Weight Loss Following Proximal Roux-en-Y Gastric Bypass

BACKGROUND

Standard Roux-en-Y gastric bypass (RYGB) typically manipulates the proximal portion of the small intestine, leaving a variable and unknown common channel and total alimentary limb length (TALL). Despite high variability in postoperative weight loss, the factors contributing to this variability remain unknown. Given the known variability in small intestinal length, this unmeasured variability in TALL may be associated with weight loss responses.

OBJECTIVE

To test the hypothesis that TALL is associated with postoperative weight loss following primary laparoscopic Roux-en-Y gastric bypass (RYGB).

SETTING

Vanderbilt University Medical Center; Nashville, Tennessee, USA.

METHODS

A total of 329 patients were recruited for this observational study and consented to laparoscopic measurement of the entire small intestinal length at the time of primary RYGB. Of these patients, 208 had successful measurement of the small bowel length (SBL) and underwent RYGB with a fixed biliopancreatic limb length (BPL, 50 cm). Common channel length (CCL) was allowed to vary normally to test the association between TALL and postoperative weight loss.

RESULTS

Follow-up rates were 77% at 6 months and 41% at 24 months. Average SBL was 592 cm (min = 390 cm, max = 910 cm), with a standard deviation of 107 cm that led to significant variation in CCL (shortest 190 cm, longest 730 cm). Regression was used to model weight loss and body mass index, as well as percent change from baseline, for each patient given the measured TALL and CCL. Despite significant variation in TALL, there were no clinically significant effects of TALL or CCL on weight loss up to 24 months.

CONCLUSIONS

With a fixed BPL, normal variation in TALL does not significantly contribute to weight loss variability following RYGB. Future studies are needed to better understand the importance of intestinal limb lengths in primary and revisional RYGB surgery.

A Meta-Analysis Comparing RYGB with Long Biliopancreatic Limb (BPL) Versus Long Alimentary Limb (AL) in Groups with Equal or Nearly Equal Combined Bypass Lengths (Combined BPL and AL Lengths): Does Switching Seats Enhance Weight Loss?

It is well-established that extending either the biliopancreatic limb (BPL), the alimentary limb (AL), or both, results in increased combined bypass (CB) length, which in turn leads to enhanced weight loss and potential nutritional deficiencies due to heightened malabsorptive effects. However, a key question remains: Assuming no change in CB length, does altering BPL length affect outcomes? To address this question, we examined studies comparing long BPL and long AL (short BPL) while maintaining equal or nearly equal CB lengths. We conducted this systematic literature review according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We performed a meta-analysis on weight loss outcomes, adverse events and safety-related outcomes, gastrointestinal complaints, and nutritional outcomes at the 2-year mark.

Therapeutic Options for Recurrence of Weight and Obesity Related Complications After Metabolic and Bariatric Surgery: An IFSO Position Statement

Obesity is a chronic disease that may require multiple interventions and escalation of therapy throughout the years. Until recently, no universal definition existed for recurrent weight gain and insufficient weight loss. Standardization of reporting is key so outcomes can be compared and data can be pooled. The recent IFSO consensus provided standard terminology and definitions that will likely resolve this in the future, and publishers will need to enforce for authors to use these definitions. This current IFSO position statement provides guidance for the management of recurrent weight gain after bariatric surgery.

The Impact of Longer Biliopancreatic Limb Length on Weight Loss and Comorbidity Improvement at 5 Years After Primary Roux-en-Y Gastric Bypass Surgery: A Population-Based Matched Cohort Study

INTRODUCTION

Different limb lengths are used in Roux-en-Y gastric bypass (RYGB) surgery, as there is no consensus which limb length strategy has the best outcomes. The biliopancreatic limb (BPL) is thought to play an important role in achieving weight loss and associated comorbidity resolution. The objective of this study was to assess the impact of a longer BPL on weight loss and comorbidity improvement at 5 years after primary RYGB.

METHODS

All patients aged ≥ 18 years undergoing primary RYGB between 2014-2017 with registered follow-up 5 years after surgery were included. Long BPL was defined as BPL ≥ 100 cm and short BPL as BPL < 100 cm. The primary outcome was achieving at least 25% total weight loss (TWL) at 5 years. Secondary outcomes included absolute %TWL and improvement of comorbidities. A propensity score matched logistic and linear regression was used to estimate the difference in outcomes between patients with long and short BPL.

RESULTS

At 5 years, long BPL had higher odds to achieve ≥ 25% TWL (odds ratio (OR) 1.19, 95% confidence interval (CI) [1.01 - 1.41]) and was associated with 1.26% higher absolute TWL (β = 1.26, 95% CI [0.53 - 1.99]). Furthermore, long BPL was more likely to result in improved diabetes mellitus (OR = 2.17, 95% CI [1.31 - 3.60]) and hypertension (OR = 1.45, 95% CI [1.06 - 1.99]).

CONCLUSION

Patients undergoing RYGB with longer BPL achieved higher weight loss and were more likely to achieve improvement of comorbidities at 5 years.

The Impact of Early-Stage Chronic Kidney Disease on Weight Loss Outcomes After Gastric Bypass

PURPOSE

Weight loss achieved through bariatric metabolic surgery was demonstrated to be effective at reversing chronic kidney dysfunction associated with obesity-related glomerulopathy. However, robust data on how pre-operative kidney status impacts on bariatric metabolic surgery weight loss outcomes is still lacking. The aim of this study was to evaluate the impact of kidney dysfunction on weight loss outcomes after bariatric metabolic surgery.

METHODS

Patients with obesity to be submitted to gastric bypass surgery underwent a pre-operative evaluation of creatinine clearance, estimated glomerular filtration rate (eGFR), proteinuria, and albuminuria in 24-hour urine. Body mass index (BMI), % total weight loss (%TWL), and % excess BMI loss (%EBMIL) were assessed at 6 and 12 months after surgery.

RESULTS

Before surgery, patients (N=127) had a mean BMI of 39.6 ± 3.0 kg/m2, and 56.7% (n=72) had a creatinine clearance > 130 mL/min, 23.6% (n= 30) presented proteinuria > 150 mg/24h, and 15.0% (n= 19) presented albuminuria > 30 mg/24h. After surgery, the mean BMI was 27.7 kg/m2 and 25.0 kg/m2 at 6 and 12 months, respectively (p<0.0001). The %TWL was lower in patients with pre-operative eGFR < percentile 25 (34.4 ± 5.8% vs 39.4 ± 4.9%, p=0.0007, at 12 months). There were no significant correlations between weight loss metrics and pre-operative creatinine clearance rate, proteinuria, or albuminuria.

CONCLUSION

Early-stage chronic kidney disease (G2) has a negative impact on short-term weight loss outcomes after bariatric metabolic surgery, albeit in a magnitude inferior to the clinically relevant threshold.

Individuals with type 2 diabetes have higher density of small intestinal neurotensin-expressing cells

Neurotensin (NT) is a gastro-intestinal hormone involved in several pathways that regulate energy and glucose homeostasis. NT was hypothesized to act in synergy with incretin hormones to potentiate its anti-diabetic effects. Additionally, circulating NT levels were shown to rise after bariatric surgery-induced weight loss. Knowledge of NT-secreting cells distribution along the small intestine and its variation according to diabetes status could provide insights on NT role in mediating type 2 diabetes (T2D) improvement after bariatric surgery. So, our aims were to characterize NT-expressing cell distribution along the human small intestine and to compare the relative density of NT-expressing cells in the small intestine of individuals with and without T2D undergoing bariatric surgery for obesity treatment. Autopsy-derived small intestine fragments (n = 30) were obtained at every 20 cm along the entire intestinal length. Additionally, jejunum biopsies (n = 29) were obtained during elective gastric bypass interventions from patients with (n = 10) or without T2D (n = 18). NT-expressing cells were identified by immunohistochemistry and quantified via computerized morphometric analysis. NT-expressing cell density increased along the human small intestine. NT-expressing cell density was significantly higher from 200 cm distal to the duodenojejunal flexure onward, as well as in subjects with T2D when compared to those without T2D. NT-expressing cell density increases along the human small gut, and a higher density is found in individuals with T2D. This finding suggests a potential role for NT in the mechanisms of disease and T2D improvement observed after bariatric surgery.

Remission of Type II Diabetes Mellitus after Duodenal Switch: the Contribution of Common Channel Length

INTRODUCTION

The role of the common channel length in duodenal switch (DS) on remission of type II diabetes mellitus (DM), when stratifying patients based on diabetes severity, is not well understood.

METHODS

We retrospectively reviewed 341 consecutive patients with DM undergoing DS with one of three different common channel (CC) lengths (100 cm, 150 cm, and 200 cm), each with a fixed 300 cm alimentary limb (AL). Patients were stratified by insulin dependence (IDDM) versus non-insulin dependent diabetes (NIDDM). Data was collected at one year and at the last available follow-up.

RESULTS

The NIDDM group had a similar average HbA1c at last follow-up for each of the CC lengths. However, the IDDM group had lower average HbA1c with shorter CC lengths (100 cm = 5.4%, 150 cm = 6%, 200 cm = 6.4%, p < 0.05). Shorter CC lengths resulted in a greater proportion of patients achieving remission in the IDDM group (66%, 50%, 32% in the 100 cm, 150 cm, and 200 cm CC, respectively, p < 0.01). Improvements in HbA1c were independent of weight loss and average DiaRem scores were similar between CC lengths. Rates of nutritional deficiencies were higher in shorter common channel lengths. Revision for malnutrition was similar between common channel lengths (100 cm group: 3.7%; 150 cm group: 1.8%; 200 cm group: 0%, p = NS).

CONCLUSIONS

When the AL is fixed, shortening CC lengths results in improved glycemic control and remission of DM in patients with the need for insulin preoperatively. Milder forms of DM are treated well with any of the CC lengths.

American Society for Metabolic and Bariatric Surgery literature review on the effect of Roux-en-Y gastric bypass limb lengths on outcomes

This literature review is issued by the American Society for Metabolic and Bariatric Surgery regarding limb lengths in Roux-en-Y gastric bypass (RYGB) and their effect on metabolic and bariatric outcomes. Limbs in RYGB consist of the alimentary and biliopancreatic limbs and the common channel. Variation of limb lengths in primary RYGB and as a revisional option for weight recurrence after RYGB are described in this review.

Physical properties of food or bile redirection do not contribute to the intestinal adaptations after Roux-en-Y Gastric Bypass in rats

Objective

Metabolic and morphological adaptations of the intestine have been suggested to play a role in the various therapeutic benefits of Roux-en-Y Gastric Bypass (RYGB) surgery. However, the precise underlying mechanisms remain unclear. In this study, the effects of physical properties of ingested food and redirection of biliopancreatic secretions on intestinal remodeling were investigated in RYGB operated rats.

Methods

RYGB employing two different Roux Limb (RL) lengths was performed on high fat diet induced obese rats. Post-operatively, rats were fed either Solid or isocaloric Liquid diets. Metabolic and morphological remodeling of intestine was compared across both diet forms (Solid and Liquid diets) and surgical models (Short RL and Long RL).

Results

RYGB surgery in rats induced weight loss and improved glucose tolerance which was independent of physical properties of ingested food and biliopancreatic secretions. Intestinal glucose utilization after RYGB was not determined by either food form or biliopancreatic secretions. The GLUT-1 expression in RL was not influenced by physical properties of food. Furthermore, both physical properties of food and biliopancreatic secretions showed no effects on intestinal morphological adaptations after RYGB.

Conclusion

Results of this study demonstrate that physical properties of food and bile redirection are not major determinants of intestinal remodeling after RYGB in rats.

Accuracy of prediction models for long-term type 2 diabetes remission after gastric bypass

AIM

To evaluate the accuracy of DiaBetter, DiaRem, Ad-DiaRem and 5y-Ad-DiaRem scores' at predicting T2D remission 10 or more years after surgery.

METHODS

Patients with obesity and T2D (n = 126) submitted to RYGB with 10 or more years of follow-up. It was a unicentric trial. Pre-operative anthropometric and clinical data was retrieved to calculate DiaRem, DiaBetter, Ad-DiaRem and 5y-Ad-DiaRem scores, while a hospital visit was conducted to assess current diabetes status. The area under the receiver operating characteristic (AUROC) curve was calculated as estimate of the scores' accuracy to predict long-term T2D remission.

RESULTS

Among the entire cohort (n = 126), 70 subjects (55.6%) achieved and maintained T2D remission 10 or more years after RYGB. The 5y-Ad-DiaRem score was the one that depicted the highest discriminative power (AUROC = 0.838) to predict long-term T2D remission when compared to DiaBetter (AUROC = 0.735), DiaRem (AUROC = 0.721) and Ad-DiaRem (AUROC = 0.720).

CONCLUSION

The score with highest accuracy to predict long-term T2D remission after RYGB surgery was the 5y-Ad-DiaRem. Yet, the available scores accuracy to predict T2D remission in the long term is still suboptimal, highlighting the unmet need for a better scoring system.

Thromboembolic Complications After Bariatric Surgery: Is the High Risk Real?

INTRODUCTION

Nowadays, a large number of bariatric surgery (BS) procedures are undertaken worldwide as surgery has become an efficient strategy to treat the obesity epidemic. The risk of venous thromboembolism (VTE) is increased in patients undergoing BS not only due to the intrinsic surgical risk but also because patients with obesity have a 2-3-fold higher risk of VTE. The optimal strategy for VTE prevention in BS setting, including optimal dose and thromboprophylaxis regimen, is still not fully clarified. The aim of this study was to report a bariatric high-volume center experience and to propose a practical thromboprophylaxis protocol for this population.

METHODS

A single-center, observational, retrospective, and longitudinal study was conducted from January 2018 to December 2020, a total of 901 patients who underwent primary and revisional bariatric surgery were included.

RESULTS

The overall frequency of VTE events was 0.44% (n=4), one patient had pulmonary embolism (PE) during index hospital admission; another patient had simultaneous deep venous thrombosis (DVT) and PE, two months after surgery; and two other patients had DVT, nine and 16 months after surgery. The median time for VTE was four months. The incidence of females was 75% (n=3) and the median age was 57 years. Only one female patient was using oral contraception. None had a previous history of thromboembolic events, chronic venous insufficiency, or other known diseases that could increase the VTE risk.

CONCLUSION

Considering the outcomes reported by this experienced center with low rates of thromboembolic events, we suggest a thromboprophylaxis protocol that can be easily applied to the majority of bariatric patients.

Effects of short or long biliopancreatic limb length after laparoscopic Roux-en-Y gastric bypass surgery for obesity: a propensity score-matched analysis

Purpose

Although recent studies reported superior weight reduction in patients undergoing Roux-en-Y gastric bypass (RYGB) with long biliopancreatic limb (BPL), no recommendation regarding limb lengths exists. This study compares weight loss and resolution of obesity-related comorbidities in patients undergoing RYGB with either long or short BPL.

Methods

A retrospective data search from medical records was performed. A total of 308 patients underwent laparoscopic RYGB with a BPL length of either 100 cm or 50 cm. Data was analyzed before and after propensity score matching.

Results

No statistically significant difference in weight reduction between long and short BPL RYGB in terms of percentage of excess weight loss (%EWL) (86.4 ± 24.5 vs. 83.4 ± 21.4, p = 0.285) and percentage of total weight loss (%TWL) (32.4 ± 8.4 vs. 33.0 ± 8.3, p = 0.543) was found 24 months after surgery. Propensity score–matched analysis did not show any statistically significant difference between groups in both %EWL and %TWL. No significant difference between long and short BPL RYGB in the resolution of obesity-related comorbidities was noted 24 months after surgery.

Conclusion

Weight loss and resolution of obesity-related comorbidities were not significantly different between long and short BPL RYGB 24 months after surgery.

Standard Biliopancreatic Limb (50 cm) Roux-en-Y Gastric Bypass Versus Long Biliopancreatic Limb (100 cm) Roux-en-Y Gastric Bypass in Patients with Body Mass Index 40-50 kg/m2: a Randomized Prospective Study

BACKGROUND

Roux-en-Y gastric bypass (RYGB) is a widely performed procedure worldwide especially with the presence of associated medical conditions. Patients with body mass index (BMI) 40-50 kg/m² are at more risk of weight regain and relapse of comorbidities. There is a controversy on the optimum alimentary (AL) and biliopancreatic (BPL) limb lengths to be used in RYGB to achieve weight loss and remission of comorbidities without causing nutritional deficiencies in those patients.

STUDY DESIGN

hundred-and-fifty patients with BMI between 40 and 50 kg/m² were divided equally into 2 groups undergoing standard RYGB (S-RYGB) with AL:150 cm and BPL: 50 cm and long biliopancreatic RYGB (L-RYGB) with AL: 100 cm and BPL: 100 cm. BMI, % of total weight loss (%TWL), effect on diabetes (DM), hypertension (HTN), dyslipidemia, and nutritional statuses were recorded at 1, 2, and 3 years.

RESULTS

Only 64/75 patients in S-RYGB and 57/75 patients in L-RYGB completed the study. L-RYGB had faster weight loss, higher %TWL, and less BMI than S-RYGB with the maintenance of achieved weight. L-RYGB had better control of DM and dyslipidemia than S-RYGB. There were no significant differences in nutritional status between S-RYGB and L-RYGB rather than lower levels of calcium and Hb and higher levels of PTH in L-RYGB yet they remain within the normal range.

CONCLUSION

The application of L-RYGB helps in achieving faster weight loss for a longer period with better remission of associated comorbidities as DM, HTN, and dyslipidemia in patients with BMI 40-50 kg/m² but with effects on the nutritional status.

Meta-analysis of Long-Term Relapse Rate of Type 2 Diabetes Following Initial Remission After Roux-en-Y Gastric Bypass

This study aims to determine the long-term relapse rate of type 2 diabetes (T2DM) following initial remission after Roux-en-Y gastric bypass (RYGB) surgery. We searched studies in PubMed, Embase, and the Cochrane Library. A total of 17 eligible studies were included for analysis. Meta-analysis suggested a pooled long-term relapse rate of 0.30 (95% confidence interval [CI], 0.26–0.34) and a remission rate of 0.63 (95% CI, 0.55–0.72) after RYGB and a hazard ratio of 0.73 (95% CI, 0.66–0.81) for comparison of RYGB and sleeve gastrectomy (SG). Subgroup analyses established pooled results. This study suggested RYGB may be a preferred regime for obese patients with T2DM because it is associated with lower long-term relapse and relatively higher initial remission and was also superior to SG due to lower risk of recurrence.

Midterm Results from the Dutch Common Channel Trial (DUCATI): Superior Weight Loss Results of the Long Roux Limb Gastric Bypass in Comparison to the Standard Bypass at 3-Year Follow-Up

In the multi-center Dutch Common Channel Trial (DUCATI), a very long Roux limb Roux-en-Y gastric bypass (VLRL-RYGB: BP-limb 60 cm, Roux limb variable, and common channel 100 cm) was compared to a standard Roux-en-Y gastric bypass (S-LRYGB: BP-limb 60 cm, Roux limb 150 cm, and common channel variable) in the treatment of morbidly obese patients. As all trial patients are beyond 3-year follow-up a midterm analysis was performed to investigate the effect of the VLRL-RYGB.

METHODS

A total of 444 patients were randomized (1:1) to receive either a VLRL-RYGB or a S-LRYGB. Follow-up results for weight loss, effect on obesity-related comorbid conditions, complications, reoperation, and malnutrition are investigated.

RESULTS

At 3-year follow-up a significant difference in %TWL (34.0% vs. 31.4%, p = 0.017) and %EWL (84.7% vs. 76.6%, p = 0.043) was observed in favor of VLRL-LRYGB group. Overall complication rate 3-years after surgery was 15.8% in the VLRL-LRYGB group vs. 9% in the S-LRYGB group (p = 0.031). Eight (3.6%) patients in the VLRL-LRYGB group versus 2 (0.9%) in the S-LRYGB group (p = 0.055) required revisional surgery for malabsorption. In the VLRL-LRYGB group 71.9% of patients had resolution of T2DM versus 48.9% in the S-LRYGB group (p = 0.044).

CONCLUSION

At midterm FU a considerable, significantly increased effect on weight loss of the VLRL-LRYGB was observed compared to the S-LRYGB, with a higher risk of overall complications, but no significant nutritional side effects. These results might impact the current view on the value of the Roux limb in the discussion on optimum limb lengths in Roux-en-Y gastric bypass surgery.

Effect of Roux-en-Y Gastric Bypass with Different Lengths of Biliopancreatic and Alimentary Limbs for Patients with Type 2 Diabetes Mellitus and a BMI < 35 kg/m2: 5-Year Outcomes in Chinese Patients

PURPOSE

There have been no definite conclusions about the biliopancreatic limb (BPL) and alimentary limb (AL) lengths in Roux-en-Y gastric bypass (RYGB) operations for different populations and BMIs. Western scholars have performed many studies on the lengths of the BPL and AL in patients with a BMI ≥ 35 kg/m². However, for diabetic Chinese patients with BMI < 35 kg/m², few people have compared the effects of different BPL and AL lengths on patient prognosis.

PATIENTS AND METHODS

Clinical data were collected prospectively and analyzed retrospectively for 87 patients with type 2 diabetes (T2DM) who underwent RYGB with a BPL of 50 cm and an AL of 50 cm (BPL50/AL50) or with a BPL of 100 cm and an AL of 100 cm (BPL100/AL100) and who were followed up for 5 years.

RESULTS

The cohort included 42 patients in the BPL50/AL50 group and 45 patients in the BPL100/AL100 group. At 5 years, there were significant differences in BMI, total weight loss (TWL%), glycosylated hemoglobin, and homeostasis model assessment insulin resistance between BPL50/AL50 and BPL100/AL100 (P < 0.05). Diabetes remission rate of the BPL100/AL100 group was significantly higher than that of the BPL50/AL50 group. Diabetes remission at 1 year after surgery correlated with the length limb (BPL + AL), duration of diabetes and TWL%. There was no difference in complications between BPL50/AL50 and BPL100/AL100.

CONCLUSIONS

RYGB with BPL100/AL100 is a safe and effective treatment for diabetic patients with a BMI < 35 kg/m² and offers significant improvement in weight loss and glycemic control.

Roux-en-Y Gastric Bypass with Long Biliopancreatic Limb Compared to Single Anastomosis Sleeve Ileal (SASI) Bypass in Treatment of Morbid Obesity

PURPOSE

Bariatric surgery is the most effective treatment of morbid obesity. Bariatric procedures employ different mechanisms of action to induce weight loss. The present study aimed to compare single-anastomosis sleeve ileal (SASI) bypass and roux-en-Y gastric bypass RYGB with long biliopancreatic limb (BPL) in terms of weight loss, remission of comorbidities, complications, and nutritional status.

METHODS

This was a single-center cohort study on patients with morbid obesity who underwent RYGB with long BPL of 150 cm or SASI bypass. The main outcome measures were weight loss and improvement in comorbidities at 12 months, nutritional status, and complications.

RESULTS

The present study included 92 patients (59.8% females) of a mean age of 38.4 years and mean BMI of 42 kg/m2. RYGB and SASI bypass were followed by a significant decrease in body mass index at 12 months and were comparable in terms of excess and total weight loss. Improvement in comorbidities after the two procedures was similar. The serum albumin levels showed a significant decline after RYGB, but not after SASI bypass. The postoperative serum iron levels were higher after SASI bypass than after RYGB. There was no significant difference in regard to complication rates (13% vs 4.3%, p = 0.27).

CONCLUSIONS

RYGB with long BPL and SASI bypass achieved satisfactory weight loss and improvement in comorbidities that were comparable among the two groups. Long BPL RYGB was followed by a significant decrease in serum albumin and iron levels at one year, which was not observed after SASI bypass.

How Sustained is Roux-en-Y Gastric Bypass Long-term Efficacy? : Roux-en-Y Gastric Bypass efficacy

Purpose

The rate of weight regain after Roux-en-Y Gastric Bypass (RYGB) can hamper the procedure long-term efficacy for obesity treatment and related comorbidities. To evaluate the rate of weight loss and comorbidity remission failure 10 years or more after RYGB surgery.

Materials and methods

Retrospective observational cohort study. Patients submitted to RYGB for obesity treatment at a single centre with 10 years or more after surgery underwent a clinical reassessment.

Results

Among the subjects invited for clinical revaluation (n = 585), only those who performed RYGB and attended the hospital visit were included in the study (n = 281). The pre-operative mean body mass index (BMI) was 44.4 ± 6.1 kg/m². Mean post-operative time was 12.2 ± 1.1 years. After surgery, mean BMI was significantly lower 33.4 ± 5.8 kg/m² (p < 0.0001), 29.5% with a BMI < 30 kg/m². Mean Total Weight Lost (%TWL) was 24.3 ± 11.4%, reaching a %TWL ≥ 20% in 70.1% with a mean %TWL of 30.0 ± 7.0%. Co-morbidities remission rate was 54.2% for type 2 diabetes, 34.1% for hypertension, 52.4% for hyperlipidemia and 50% for obstructive sleep apnea. Early complications rate was 13.2% and revision surgery occurred in 2.8% of patients. Four patients died of RYGB complications within the first 90 days after surgery.

Conclusion

RYGB has a high rate of long-term successful weight loss and obesity-associated comorbidity improvement. Weight loss failure requiring revision surgery occurs in a small proportion of patients. Our data confirms the long-term effectiveness of RYGB as primary bariatric intervention.

Graphical abstract

Long versus short biliopancreatic limb in Roux-en-Y gastric bypass: short-term results of a randomized clinical trial

BACKGROUND

The Roux-en-Y gastric bypass continues to be one of the most performed bariatric surgeries because of its adequate balance of outcomes, complications, and durability. Recently, the role of the biliopancreatic limb on weight loss and co-morbidity control has gained attention because it seems to have a positive impact based on limb length.

OBJECTIVE

To compare results at 12 months of a "standard" (group 1) versus a long (group 2) biliopancreatic limb bypass. Biliopancreatic limbs were 50 cm and 200 cm, and alimentary limbs were 150 cm and 50 cm, respectively.

SETTING

Academic Referal Center; Mexico City; Public Seeting.

METHODS

Randomized study with patients undergoing both types of surgeries at a single academic center from 2016 to 2018. The analysis included weight loss, co-morbidity control (diabetes and hypertension), biochemical panel, operative outcomes, and complications.

RESULTS

Two-hundred ten patients were included (105 in each group). Almost all data were homogenous at baseline. Female sex comprised 86.1% of cases, with a mean body mass index of 43.5 kg/m². Excess weight loss (77.6 ± 15.7% versus 83.6 ± 16.7%; P = .011) and total weight loss (33.5 ± 6.4% versus 37.1 ± 7.1%; P < .001) was higher in group 2; better HbA1C levels were also observed. Co-morbidity outcomes, operative data, and complications were similar between groups.

CONCLUSION

The Roux-en-Y gastric bypass with 200 cm of biliopancreatic limb length induces more weight loss at 12 months than a 50 cm limb length. Better HbA1C levels were also observed, but similar effects on co-morbidities and complications were noted.

Revisional Surgery for Insufficient Loss or Regain of Weight After Roux-en-Y Gastric Bypass: Biliopancreatic Limb Length Matters

INTRODUCTION

Weight regain after laparoscopic Roux-en-Y gastric bypass (RYGB) occurs in up to 35% of patients. Revisional surgery may be applied. Conversion from RYGB to a long biliopancreatic limb (BPL) RYGB is a potential option for revisional surgery and short-term results are promising.

METHODS

All patients who underwent conversion to long BPL RYGB due to weight loss failure, defined as excess weight loss (EWL) < 50% or body mass index (BMI) > 35 kg/m², were assessed. Proximal RYGB or very very long limb RYGB (VVLL RYGB) was modified by shortening of the total alimentary limb length (TALL) to create a long BPL.

RESULTS

A total of 28 patients received revisional surgery from either PRYGB (n = 22) or VVLL RYGB (n = 6). Mean age at operation was 45.3 ± 10.4 years, with 78% females. Mean prerevisional BMI was 41.7 ± 4.4 kg/m². Mean time to revision was 76.5 ± 38.5 months. Limb lengths were 150 cm (95% CI 133-156 cm) for RL and 100 cm (95% CI 97-113 cm) for CC, thus providing a total median alimentary limb length of 250 (95% CI 238-260 cm). Additional %EWL and TWL improved significantly in long-term. Five years postoperatively, all patients (n = 9) had an EWL% > 50%. Six patients (21.4%) required reoperation due to severe malnutrition during the postoperative course.

CONCLUSION

Conversion from RYGB to BPL RYGB leads to significant additional weight loss in the long term. However, the morbidity is relevant, especially severe protein malnutrition and the frequency of revisional surgery. Therefore, this type of surgery should not be done routinely.

Can Metabolite and Hormone Profiles Provide a Rationale for Choosing Between Bariatric Procedures?

PURPOSE

There are no formal guidelines for choosing among different bariatric surgery procedures for obesity treatment. So, our aim was to evaluate whether post-absorptive metabolite and hormone profiles could aid the surgeon decision when considering bariatric surgery interventions.

MATERIALS AND METHODS

Subjects (N=38) previously submitted to biliopancreatic diversion with duodenal switch (BPD-DS, n=9), single anastomosis duodenal-ileum bypass with sleeve gastrectomy (SADI-S, n= 9), long biliopancreatic limb Roux-en-Y gastric bypass (RYGB-M, n= 11), and classic RYGB (RYGB-C, n= 9) underwent a mixed meal test to evaluate post-absorptive glucose, total amino acid (AA), insulin, and GLP-1 profiles.

RESULTS

Glucose, AA, insulin, and GLP-1 excursions were lower after BPD-DS when compared to other surgeries. SADI-S resulted in lower glucose but similar AA and insulin excursions when compared to RYGB-M. The highest GLP-1 excursion was observed after RYGB-M. There were no significant differences in glucose or AA post-prandial excursions between RYGB procedures, yet insulin excursion was higher after RYGB-C when compared to RYGB-M.

CONCLUSION

Post-prandial metabolite excursions diverge across bariatric procedures being lowest after BPD-DS, intermediate after SADI-S, and highest after RYGB, in parallel with the anti-diabetic efficacy and malabsorption risk reported for each type of intervention. SADI-S and RYGB-M seem to elicit similar post-prandial hormonal profiles, with potentially lower risk of protein malnutrition when compared to BPD-DS. Post-absorptive metabolite and hormone profiles could provide a rationale as decision-aid when choosing among bariatric surgery interventions, as long as these findings are validated in future trials.

Does the Length of the Common Channel as Part of the Total Alimentary Tract Matter? One Year Results from the Multicenter Dutch Common Channel Trial (DUCATI) Comparing Standard Versus Distal Roux-en-Y Gastric Bypass with Similar Biliopancreatic Bowel Limb Lengths

PURPOSE

Although the laparoscopic Roux-en-Y Gastric Bypass (LRYGB) is the gold-standard bariatric procedure, it remains uncertain what the optimal bowel limb lengths are to accomplish maximal weight loss while minimizing nutritional deficiencies and related gastro-intestinal complaints. The aim of this randomized controlled multicenter trial is to investigate the effect of significant lengthening of the length of the Roux limb (RL) at the cost of the length of the common channel (CC) while keeping the biliopancreatic limb (BPL) lengths the same on both study arms.

METHODS

Four hundred forty-four patients were randomized to receive either a Very Long Roux Limb LRYGB (VLRL-LRYGB) (variable RL length, BPL 60 cm, and CC 100 cm) or a Standard LRYGB (S-LRYGB) (RL 150 cm, BPL 60 cm, and a variable CC length). Results at 1-year follow-up for weight loss, effect on obesity-related comorbid conditions, complications, re-operation rate, malnutrition rate, and re-admission rate were investigated.

RESULTS

Weight loss at 1-year showed no significant differences for %EWL (84.3% versus 85.3%, p = 0.72) and %TWL (34.2% versus 33.6%, p = 0.359) comparing VLRL-LRYGB versus S-LRYGB. Malabsorption requiring surgical bowel length adjustment was observed in 1.4% in VLRL-LRYGB group versus 0.9% in S-LRYGB group (p = 0.316).

CONCLUSION

Significant lengthening of the RL at the cost of the common channel seems to have no effect on the weight loss at 1-year follow-up, which supports the theory that absorption of nutrients also occurs in the RL. Nevertheless, long-term results of the VLRL-LRYGB have to be awaited to draw final conclusions as part of the discussion towards optimal limb length in LRYGB surgery.

Defining remission of type 2 diabetes in research studies: A systematic scoping review

BACKGROUND

Remission has been identified as a top priority by people with type 2 diabetes. Remission is commonly used as an outcome in research studies; however, a widely accepted definition of remission of type 2 diabetes is lacking. A report on defining remission was published (but not formally endorsed) in Diabetes Care, an American Diabetes Association (ADA) journal. This Diabetes Care report remains widely used. It was the first to suggest 3 components necessary to define the presence of remission: (1) absence of glucose-lowering therapy (GLT); (2) normoglycaemia; and (3) for duration ≥1 year. Our aim is to systematically review how remission of type 2 diabetes has been defined by observational and interventional studies since publication of the 2009 report.

METHODS AND FINDINGS

Four databases (MEDLINE, EMBASE, Cochrane Library, and CINAHL) were searched for studies published from 1 September 2009 to 18 July 2020 involving at least 100 participants with type 2 diabetes in their remission analysis, which examined an outcome of type 2 diabetes remission in adults ≥18 years and which had been published in English since 2009. Remission definitions were extracted and categorised by glucose-lowering therapy, glycaemic thresholds, and duration. A total of 8,966 titles/abstracts were screened, and 178 studies (165 observational and 13 interventional) from 33 countries were included. These contributed 266 definitions, of which 96 were unique. The 2009 report was referenced in 121 (45%) definitions. In total, 247 (93%) definitions required the absence of GLT, and 232 (87%) definitions specified numeric glycaemic thresholds. The most frequently used threshold was HbA1c<42 mmol/mol (6.0%) in 47 (20%) definitions. Time was frequently omitted. In this study, a total of 104 (39%) definitions defined time as a duration. The main limitations of this systematic review lie in the restriction to published studies written in English with sample sizes of over 100. Grey literature was not included in the search.

CONCLUSIONS

We found that there is substantial heterogeneity in the definition of type 2 diabetes remission in research studies published since 2009, at least partly reflecting ambiguity in the 2009 report. This complicates interpretation of previous research on remission of type 2 diabetes and the implications for people with type 2 diabetes. Any new consensus definition of remission should include unambiguous glycaemic thresholds and emphasise duration. Until an international consensus is reached, studies describing remission should clearly define all 3 components of remission.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42019144619.

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.

Does Reconstruction Type After Gastric Resection Matters for Type 2 Diabetes Improvement?

BACKGROUND

Gastrointestinal (GI) surgery involving gastric resection and bypass of intestinal segments was reported to facilitate glucose control in obese patients with type 2 diabetes (T2D).

AIM

Our aim was to assess whether the type of post-gastrectomy GI reconstruction also influences glucose control in T2D patients with BMI below 35 kg/m² submitted to gastrointestinal surgery without bariatric intention.

METHODS

A cohort of T2D Caucasian patients (n = 40) with upper GI malignancy (n = 33) or complicated reflux disease (n = 7) were submitted to either a gastrectomy plus Billroth II (BII) gastrojejunal anastomosis (n = 17), a gastrectomy plus Roux-en-Y gastrojejunostomy (RY) reconstruction (n = 18; subtotal gastrectomy n = 7 and total gastrectomy n = 11), or atypical gastrectomy without reconstruction (no-R) (n = 5). Patients were evaluated before and 2 years after surgery for body weight, Hb1Ac, need of glucose lowering drugs, and presence of diabetes.

RESULTS

Body mass index (BMI) decreased after every surgical procedure when compared to baseline (- 0.9 ± 0.8 kg/m² for BII vs - 4.3 ± 2.6 kg/m² for RY vs - 4.6 ± 2.5 kg/m² for no-R, p < 0.05), which was only significantly different after RY surgeries. Diabetes remission occurred in 5.9% of BII patients, in 27.8% of RY patients, and 0% of no-R patients, while in patients with persistent T2D, the needs for glucose-lowering drugs were significantly also decreased after RY (31.3% BII vs 66.7% RY vs 25% no-R, p = 0.03).

CONCLUSIONS

T2D Caucasian patients undergoing post-gastrectomy GI reconstructions without a bariatric intention experience a significant improvement of T2D, in a magnitude that could be influenced by the technical procedure performed in favor of RY reconstruction. Thus, presence of T2D should be taken into consideration when deciding for the type of post-gastrectomy GI reconstruction.

Limb Length in Gastric Bypass in Super-Obese Patients-Importance of Length of Total Alimentary Small Bowel Tract

BACKGROUND

In super-obese patients, rates of weight loss failure and weight regain are high after RYGB. In order to improve weight loss, lengthening of the biliopancreatic limb is vital. In this study, efficacy and safety of two types of RYGB with 2-m BP-limb were assessed in improving weight loss and in the resolution of comorbidities compared with standard RYGB in a long-term follow-up.

METHODS

This is a retrospective cohort analysis on 671 super-obese patients operated in a 10-year period. Patients were classified into three groups: (1) 155 patients; roux limb 150 cm, BP-limb 60 cm; (2) 230 patients; roux limb 60 cm, BP-limb 200 cm; and (3) 286 patients; roux limb 150 cm, BP-limb 200 cm. EWL, TWL, BMI, failure, weight regain, comorbidity resolution, nutritional status, and complications were assessed.

RESULTS

Total alimentary limb length was shortened with 60 cm in group 1 and with 200 cm in groups 2 and 3. EWL, BMI change, and TWL were higher in the 2-m BP-limb groups vs group 1. No differences in complication rates were found, except higher frequency of marginal ulcers in patients with a shorter roux limb. EWL failure was higher in group 1 (10.3%) vs the other groups (4.3%; 5.2%). Group 3 had significantly less weight regain (26.6%). Remission of comorbidities was higher in the 2-m BP-limb groups at expense of nutritional and vitamin deficiencies (3.9%; 5.9%). No difference in hypoalbuminemia was noted.

CONCLUSION

Lengthening of the BP-limb gives significantly higher weight loss, lower rate of EWL failure, and lesser weight regain along with better resolution of obesity-associated comorbidities.

Gut Microbiota Imbalance Can Be Associated with Non-malabsorptive Small Bowel Shortening Regardless of Blind Loop

INTRODUCTION

Some traditional bariatric surgery procedures may lead to functional gut shortening, which may unsettle the fine-tuned gastrointestinal physiology and affect gut microbiota balance.

PURPOSE

Evaluate the gut microbiota behavior in rat models facing gut shortening due to intestinal bypass.

MATERIALS AND METHODS

Wistar rats (n = 17) were randomly distributed in three groups: (1) sham group (n = 5); (2) blind loop group (n = 6); and (3) resection group (n = 6). Intestinal samples and feces were analyzed to measure bacterial concentrations (small intestinal bacterial overgrowth-SIBO) 12 weeks after the experimental procedures. Bacterial translocation (BT) was investigated in the mesenteric lymph node (MLN), liver, spleen, and lung of the animals. In addition, inflammatory aspects were investigated in their liver and small bowel through histological analysis.

RESULTS

Regardless of blind loop, gut shortening groups recorded similar high level of bacterial concentrations in intestine compartments, greater than that of the sham group (p ≤ 0.05). BT was only observed in the MLN of gut shortening models, with higher percentage in the blind loop group (p ≤ 0.05). The gut and liver histopathological analysis showed similar low-grade chronic inflammation in both gut shortening groups, likely associated with SIBO/BT events.

CONCLUSION

Sustained SIBO/BT was associated with proximal gut shortening in half regardless of blind loop, whereas the GI tract's ability to restore gut microbiota balance after a surgical challenge on the small bowel appears to be linked to the functional remaining gut.

Proximal Roux-en-Y gastric bypass: Addressing the myth of limb length

BACKGROUND

Some studies suggest that changes in weight or metabolic outcomes are affected by the lengths of the gastrointestinal limbs in the Roux-en-Y gastric bypass.

METHODS

Participants (N = 1,770) underwent primary Roux-en-Y gastric bypass and were followed ≤7 years in the Longitudinal Assessment of Bariatric Surgery-2, a multicenter US cohort study. Alimentary limb and biliopancreatic limb lengths were measured according to research protocol; common channel was measured in a subsample (N = 547). Aimentary limb, biliopancreatic limb, and common channel ratio to total small bowel length were calculated.

RESULTS

Median presurgery body mass index was 46 (25th-75th percentile: 43-51) kg/m2. Medians (25th-75th percentiles) for alimentary limb length were 125 cm (100-150), for biliopancreatic limb length were 50 cm (50-60), and common channel length were 410 cm (322-520). Statistics for ratios to the small bowel length were 0.23 (0.18-0.27) for alimentary limb, 0.09 (0.07-0.10) for biliopancreatic limb, and 0.69 (0.63-0.73) for common length. There were no significant associations between alimentary limb, biliopancreatic limb, common channel, alimentary limb ratio, biliopancreatic limb ratio or common channel ratio, and either weight loss or improvement in cardiometabolic outcomes.

CONCLUSION

The common channel length in Roux-en-Y gastric bypass is highly variable between individuals. None of the limb lengths in this study, nor alimentary limb, biliopancreatic limb, or common channel ratios, seem to be related to weight loss or metabolic improvements >7 years.

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.

Outcomes of Long Pouch Gastric Bypass (LPGB): 4-Year Experience in Primary and Revision Cases

BACKGROUND

One of the most important complications of the one anastomosis gastric bypass (OAGB) is enterobilio acid reflux (EBAR). We report the concept of the long pouch Roux-en-Y gastric bypass (LPRYGB) meaning a Roux-en-Y with a long pouch and a 100-cm alimentary limb to avoid EBAR, with a long biliopancreatic limb to increase metabolic effects.

METHODS

A total of 300 LPRYGB cases in a 4-year period, with a 90% follow-up rate, were analysed. Anthropometric, technical feasibility, morbidity, weight loss and comorbidity outcomes were analysed.

RESULTS

The percentage total weight loss (%TWL) was 30.5% at 4 years of follow-up (32.3% in primary and 28.3% in revisions). Six intra-operative (2%) and 28 postoperative complications (9.3%) were seen. Out of this 28 complications, 11 (3.6%) were late complications. Reoperations were performed in 15 patients (5.0%). Clinically relevant EBAR was present in 3 cases only (1%) 4 years after the operation.

CONCLUSIONS

The LPRYGB combines the main advantages of the OAGB (light restriction and moderate malabsorption) with the anti-reflux effect from the Roux-en-Y diversion.

Nutritional safety of oncometabolic surgery for early gastric cancer patients: a prospective single-arm pilot study using a historical control group for comparison

BACKGROUND

Oncometabolic surgery (OS) is a modification of the Roux-en Y reconstruction method, in which the lengths of the biliopancreatic and Roux limbs are longer than that with conventional surgery (CS). Although OS is performed to improve postoperative glycemic control in gastric cancer patients with type 2 diabetes mellitus (T2DM), its postoperative nutritional safety has not been clarified. This prospective pilot study evaluated the safety and feasibility of OS in early gastric cancer patients.

METHODS

This study evaluated 20 patients with clinical T1N0 stage and preoperative body mass index (BMI) ≥ 32.5 kg/m², or ≥ 27.5 kg/m² with comorbidities, who underwent OS. Primary outcomes were cumulative incidences of anemia and deficiencies in iron and vitamin B12 after 1 year. The outcomes were compared to those of a matched historical control group.

RESULTS

The cumulative incidences of anemia (15.0% vs. 10.0%, P = 0.99), iron deficiency (15.0% vs. 10.0%, P = 0.99), and vitamin B12 deficiency (10.0% vs. 0%, P = 0.47) did not differ significantly in the OS and CS groups. However, median vitamin B12 concentration tended to be lower (395.8 vs. 493.7 pg/mL, P = 0.06) and reductions in vitamin B12 concentration tended to be greater (174.7 vs. 123.0 pg/mL, P = 0.07) in the OS group. BMI loss was similar in the two groups (2.9 vs. 2.8 kg/m², P = 0.80). Remission rates of hypertension (68.8% vs. 41.2%, P = 0.22) and T2DM (77.8% vs. 50.0%, P = 0.58) were higher in the OS group.

CONCLUSION

Nutritional parameters did not differ significantly in the OS and CS groups. Vitamin B12 levels should be carefully monitored after OS.

Protein deficiency after gastric bypass: The role of common limb length in revision surgery

BACKGROUND

Bariatric surgery, especially the gastric bypass procedure, is an effective therapy for morbid obesity, but may reduce protein absorption and induce protein deficiency (PD). A recent study reported an issue about common limb length for PD.

OBJECTIVE

This study aimed to examine the prevalence of PD after gastric bypass surgery and investigate the role of common limb length in PD-related revision surgery.

SETTING

Hospital-based bariatric center.

METHODS

From 2001 to 2016, 2397 patients with morbid obesity who underwent bariatric/metabolic surgery with 1-year follow-up were recruited. Serum albumin and total protein were measured before and 1 year after surgery. Medical records of patients who underwent revision surgery due to PD were reviewed.

RESULTS

The overall prevalence of PD was .5% preoperatively. The prevalence of PD increased to 2.0% at 1 year after surgery. The incidence was highest in one-anastomosis gastric bypass (2.8%) followed by Roux-en-Y gastric bypass (1.8%). Until the end of follow-up, all 19 patients who underwent revision surgery for intractable PD had a relatively short common limb length of <400 cm. After elongation of the common limb length to >400 cm in revision surgery, PD improved in all patients.

CONCLUSIONS

A subset of patients can develop PD after gastric bypass surgery when the common limb length is <400 cm. In patients with intractable PD after gastric bypass surgery, revision surgery for elongation of common limb length to >400 cm is mandatory to avoid PD-related complications.

Gut adaptation after metabolic surgery and its influences on the brain, liver and cancer

Metabolic surgery is the best treatment for long-term weight loss maintenance and comorbidity control. Metabolic operations were originally intended to change anatomy to alter behaviour, but we now understand that the anatomical changes can modulate physiology to change behaviour. They are no longer considered only mechanically restrictive and/or malabsorptive procedures; rather, they are considered metabolic procedures involving complex physiological changes, whereby gut adaptation influences signalling pathways in several other organs, including the liver and the brain, regulating hunger, satiation, satiety, body weight, glucose metabolism and immune functions. The integrative physiology of gut adaptation after these operations consists of a complex mechanistic web of communication between gut hormones, bile acids, gut microbiota, the brain and both enteric and central nervous systems. The understanding of nutrient sensing via enteroendocrine cells, the enteric nervous system, hypothalamic peptides and adipose tissue and of the role of inflammation has advanced our knowledge of this integrative physiology. In this Review, we focus on the adaptation of gut physiology to the anatomical alterations from Roux-en-Y gastric bypass and vertical sleeve gastrectomy and the influence of these procedures on food intake, weight loss, nonalcoholic fatty liver disease (NAFLD) and cancer. We also aim to demonstrate the underlying mechanisms that could explain how metabolic surgery could be used as a therapeutic option in NAFLD and certain obesity-related cancers.

Diabetic and Elder Patients Experience Superior Cardiovascular Benefits After Gastric Bypass Induced Weight Loss

Background/Objetives: Obesity and obesity related co-morbidities are well-recognized risks for cardiovascular (CV) disease and mortality. Weight loss improves CV risk factors and the efficacy of bariatric surgery in decreasing CV mortality is now well-established. Our aim was to assess CV risk progression and occurrence of CV events in a cohort of patients that underwent Roux-en-Y gastric bypass (RYGB) for obesity treatment in a single academic public center. Subjects and Methods: Ten year CV risk was estimated using the Framingham Equation at baseline and 2 years after RYGB surgery in our patients cohort (n = 260). In the subgroup with a follow-up time longer than 4 years after surgery (n = 185; mean 5.4 ± 0.1 years), CV risk adjusted for the time length after RYGB was similarly estimated and the occurrence of CV events for outcome adjudication was monitored during the same time period by reviewing the hospital patients' record, the electronic national health system patient register and our center outpatient clinic records. Results: Ten year CV risk was significantly reduced 2 years after surgery when compared to baseline, with reductions of 1.65 ± 0.25% in the risk of CV disease. Patients with prior type 2 diabetes and aged 50 years or older experienced a significantly superior CV risk reduction, with diabetic patients experiencing a reduction of their 10-year CV disease risk of 3.58 ± 1.11% vs. a reduction of 1.31 ± 0.20% in non-diabetic patients and with the 10-year risk of CV disease dropping 3.41 ± 0.75% in patients older than 50 vs. a reduction of 0.99 ± 0.18 in patients up to 50 years. For the subgroup of patients with a longer follow-up time, baseline CV risk estimation predicted the occurrence of 6.08 ± 0.56 cardiovascular disease (CVD) events, 3.87 ± 0.39 coronary heart disease (CHD) events, 1.49 ± 0.22 myocardial infarctions (MI), 0.71 ± 0.09 strokes, 0. 28 ± 0.05 deaths from CHD and 0.35 ± 0.05 deaths from CVD. No CV events were adjudicated in this subgroup during follow-up. Conclusions: RYGB significantly improves CV risk and prevents the occurrence of CV events. For similar weight loss, diabetic and elder patients experience a superior CV risk improvement and may have additional CV benefits after bariatric surgery.