Controversies in bariatric surgery

The rationale for a duodenal switch as the primary surgical treatment of advanced type 2 diabetes mellitus and metabolic disease

Metabolic surgery improves glycemic control in patients with type 2 diabetes (T2DM) and severe obesity. Sleeve gastrectomy with loop duodenal switch (SLDS), a loop modification of biliopancreatic diversion with duodenal switch, is aimed to reduce the malabsorption, without compromising the efficacy. This study was designed to analyze the metabolic efficacy following SLDS.

Eighty patients, who underwent SLDS for T2DM and severe obesity between January 2014 and February 2020 were retrospectively analyzed. Complete T2DM remission was defined as HbA1_C < 6% in the absence of anti-diabetic medications. T2DM remission was analyzed at the 6-month and 1-year follow-ups in terms of various predictors. Prediction of T2DM remission by ABCD, DiaRem and IMS scores was analyzed. Lower ABCD scores and higher DiaRem and IMS scores indicate severe T2DM.

Following SLDS, HbA1_C significantly reduced from 8.7% to 5.5% at the 6-month and 5.1% at the 1-year follow-ups. T2DM remission was 82.5% at the 6-month and 90.8% at the 1-year follow-ups. Preoperative glycemic control positively predicted, while T2DM duration and preoperative insulin use negatively predicted T2DM remission. Higher ABCD score, lower DiaRem and IMS scores predicted higher T2DM remission. Severe hypoalbuminemia was 20% in patients with 250 cm common channel and 02% in patients with ≥300 cm common channel at the 1-year follow-up.

SLDS is an effective surgery to treat T2DM with severe obesity. Shorter T2DM duration, better preoperative glycemic control and the absence of insulin use were associated with better T2DM remission. Malabsorption was significantly lesser, when common channel was ≥300 versus 250 cm.

The DiaRem score has proven to be a reliable predictor tool for diabetes remission in Roux-en-Y gastric bypass (RYGB), as well as laparoscopic adjustable gastric band (LAGB) and laparoscopic sleeve gastrectomy (LSG). To our knowledge there are no studies that analyze DiaRem in patients undergoing biliopancreatic diversion with duodenal switch (BPD/DS).

To test the validity of the DiaRem score as a predictor of type 2 diabetes remission at 1 year post surgery in patients who underwent LABG, LSG, RYGB, and BPD/DS, as well as to develop and test a novel model that uses DiaRem to predict type 2 diabetes remission by procedure type (LABG, LSG, RYGB, and BPD/DS).

University Medical Center, United States.

A retrospective review of institutional records identified patients who underwent primary bariatric procedures (LAGB, LSG, RYGB, and BPD/DS) between January 1, 2000 to April 10, 2017, had a diagnosis of diabetes and had complete preoperative and 1-year postoperative follow-up information. A univariable logistic regression model was fit to assess the association between DiaRem score and diabetes remission. A multivariable logistic regression model was created, including procedure type and other preoperative characteristics. The area under the receiver operating curve (AUROC) was calculated to analyze the performance of both models for the entire cohort as well as a BPD/DS only subgroup.

A total study cohort of 602 was obtained. The majority of patients underwent RYGB (456; 75.7%), followed by LSG (84; 14.0%), BPD/DS (35; 5.8%), and LAGB (27; 4.5%). The multivariable regression model with RYGB as the reference procedure, showed that BPD/DS results in higher odds of type 2 diabetes remission at 1 year post surgery (adjusted odds ratio [OR] 3.29, 95% confidence interval [CI] 1.27, 8.51), while LSG (adjusted OR .52, 95%CI .29, .93) and LAGB resulted in lower odds (adjusted OR.23, 95% CI.09,.60). The univariable DiaRem model and the novel model were determined to be moderately strong in classifying diabetes remission in the entire cohort (AUROC: .79, 95% CI: .75, .83 and .82, 95% CI: .79, .85, respectively) as well as in the BPD/DS sub-group (AUROC: .85, 95% CI: .70, .99 and .84, 95% CI .69, .99, respectively).

Our study shows that the DiaRem score is a reliable tool to predict diabetes remission, amongst a wide variety of different procedures as well as specifically those receiving BPD/DS. Our novel model, which takes into account procedure type, not only shows that BPD/DS patients have the highest odds of diabetes remission than other procedures, but also that this model performs significantly better at predicting diabetes remission than DiaRem alone.

The sleeve gastrectomy (SG), Roux-en-Y gastric bypass (RYGB), and single-anastomosis duodenal-ileal bypass with SG (SADI-S) are recognized bariatric procedures. A comparison has never been made between these 3 procedures and especially in different body mass index (BMI) categories.

The study aimed to analyze a large cohort of patients undergoing either laparoscopic (L) SG, LRYGB, or LSADI-S to evaluate and compare weight loss and glycosylated hemoglobin level. The secondary aim was to compare the nutritional outcomes between LRYGB and LSADI-S.

Private practice, United States.

This is a retrospective review of 878 patients who underwent LSG, LRYGB, or LSADI-S from April 2014 through October 2015 by 5 surgeons in a single institution. For weight loss analysis, the patients were categorized into 4 different categories as follows: patients regardless of their preoperative BMI, patients with preoperative BMI <45 kg/m², patients with preoperative BMI 45 to 55 kg/m², and patients with preoperative BMI >55 kg/m².

A total of 878 patients were identified for analysis. Of 878 patients, 448 patients, 270 patients, and 160 patients underwent LSG, LRYGB, and LSADI-S, respectively. Overall, at 12 and 24 months, the weight loss was highest with LSADI-S, followed by LRYGB and LSG in all 4 categories. At 2 years, the patients lost 19.5, 16.1, and 11.3 BMI points after LSADI-S, LRYGB, and LSG, respectively. In addition, the weight loss was highest in patients with preoperative BMI <45 kg/m² and lowest in patients with preoperative BMI >55 kg/m² at 12 and 24 months. Also, there were no statistically significant differences between the nutritional outcomes between LRYGB and LSADI-S. The LSADI-S had significantly lower rates of abnormal glycosylated hemoglobin than LRYGB and LSG at 12 months (P < .001).

The weight loss outcomes and glycosylated hemoglobin rates were better with LSADI-S than LRYGB or LSG. The nutritional outcomes between LRYGB and LSADI-S were similar.

Bariatric surgery has proven to be the most durable treatment for obesity, and it also provides improvement of obesity's associated co-morbidities. Although several mechanisms for its metabolic effects have been studied, the implications of the surgically constructed anatomy on its functioning physiology have not been elucidated. This leaves some uncertainty regarding the recommended limb lengths in Roux-en-Y gastric bypass. The alimentary limb length and function has been studied extensively, but few have studied the influences of the biliopancreatic limb length.

To present a systematic review of the literature comparing variations in length of BP limb and results in order to determine BP limb length influence.

Academic Hospital, United States.

We present a systematic review of all the articles comparing variations of the biliopancreatic limb length and their results.

Thirteen articles were identified and analyzed. Most of the articles are prospective studies. Weight loss was superior in longer limbs.

Based on our review of the subject, we can conclude that the release of enterohormones in response to a food load in the distal small bowel seems to play an important role in the remission of co-morbidities. Hence, the length of the biliopancreatic limb might affect this process.

The Roux-en-Y gastric bypass (RYGB) is a very effective treatment for obesity and its related co-morbidities. However, some patients fail to achieve>50% of their excess weight loss (EWL), and others regain much of the weight that they lost.

The purpose of this study was to analyze early outcomes after conversion of RYGB to duodenal switch (DS) in terms of weight loss, change in co-morbidities, and complications.

This is a retrospective analysis from 1 surgeon at a single private institution.

We analyzed data from 32 obese patients retrospectively who underwent revision for failed RYGB. Nine patients underwent DS with Roux-en-Y reconstruction (RYDS), and 23 patients underwent single anastomosis DS between October 2012 and December 2015. Regression analyses were performed for all follow-up weight-loss data.

The patients experienced mean EWL of 16.2% over an average of 16 years (range: 0–38) with their primary RYGB surgery. Of 32 patients who underwent revision DS, 22 patients are beyond the 1-year postoperative mark (follow-up 81.8%), and 15 patients are beyond the 2-year postoperative mark (follow-up 73.3%). One patient was lost to follow-up. The patients experienced mean EWL of 31.2%, 45.1%, 51%, 54.2%, 56%, and 56.4% at 3, 6, 9, 12, 18, and 24 months, respectively, after their revisional surgery. Mean total weight loss achieved at 12 and 24 months was 27.7% and 29.2%, respectively. There was no statistical significant difference in mean %EWL at 12 months (P = .468) and 24 months (P = .266) between RYDS and single anastomosis DS.

A laparoscopic revision from RYGB to DS is an effective weight-loss operation with midterm follow-up of 2 years. Though long-term follow-up is warranted to measure recidivism, the initial data seem favorable.