Gut peptides before and following Roux-En-Y gastric bypass: A systematic review and meta-analysis

A systematic search was conducted in Medline Ovid, Embase, Scopus, and Cochrane Central Register of Controlled Trials up until March 2021 following PRISMA guidelines. Studies included evaluated ghrelin, GLP-1, PYY or appetite sensation via visual analogue scales (VASs) before and after Roux-en-Y gastric bypass (RYGB) in adults. A multilevel model with random effects for study and follow-up time points nested in study was fit to the data. The model included kcal consumption as a covariate and time points as moderators. Among the 2559 articles identified, k = 47 were included, among which k = 19 evaluated ghrelin, k = 40 GLP-1, k = 22 PYY, and k = 8 appetite sensation. Our results indicate that fasting ghrelin levels are decreased 2 weeks post-RYGB (p = 0.005) but do not differ from baseline from 6 weeks to 1-year post-RYGB. Postprandial ghrelin and fasting GLP-1 levels were not different from pre-surgical values. Postprandial levels of GLP-1 increased significantly from 1 week (p < 0.001) to 2 years post-RYGB (p < 0.01) compared with pre-RYGB. Fasting PYY increased at 6 months (p = 0.034) and 1 year (p = 0.029) post-surgery; also, postprandial levels increased up to 1 year (p < 0.01). Insufficient data on appetite sensation were available to be meta-analyzed.

A rare presentation of gastro-pleural fistula after Roux-en-Y gastric bypass, simultaneous fistula of gastric pouch, and remnant to the pleural space

Key Clinical Message

Although gastro-pleural fistulas after bariatric surgeries are rare, they are life-threatening complications that should be suspected in patients who present with gastrointestinal or respiratory symptoms after bariatric surgery.

Abstract

Previous studies showed an incidence rate of 0.2%-0.37% for gastro-pleural fistulas after bariatric surgery. We report a 56-year-old female with a rare presentation of gastro-pleural fistula after Roux-en-Y gastric bypass, simultaneous fistula of the gastric pouch, and remnant to the pleural space.

Helicobacter pylori-negative extra-nodal marginal zone B-cell lymphoma of Mucosa-Associated Lymphoid Tissue (MALT) type following Roux-en-Y Gastric Bypass (RYGB)

Gastric MALT lymphoma is a common type of non-Hodgkin's lymphoma that has the potential for cure in patients found to have concomitant Helicobacter pylori (H. pylori) infection. This case report explores the evaluation, diagnosis, and treatment of H. pylori-negative MALT lymphoma in a patient with a history of a RYGB.

Bariatric surgery outcomes in Medicare beneficiaries

Background

The Medicare population is increasing while the prevalence of obesity remains high. Bariatric surgery is the most efficacious treatment of obesity and its comorbidities. The objective of this investigation was to assess trends in utilization, readmission, mortality, and cost of bariatric surgery in the Medicare population.

Methods

Utilizing the Medicare Provider Analysis and Review database, patients with clinically severe obesity undergoing laparoscopic Roux‐en‐Y gastric bypass (RYGB), laparoscopic sleeve gastrectomy (SG), and laparoscopic adjustable gastric banding (LAGB) from 2011–2015 were identified. Trends in procedure selection, readmissions, mortality, and cost were examined. A multivariable logistic regression analysis to evaluate factors associated with readmission and mortality was performed.

Results

Of the 73,718 patients identified, 53,949 (73%) of patients were enrolled in Medicare due to disability, 19,191 (26%) due to age, and 578 (<1%) due to end stage renal disease (ESRD). Utilization of SG increased (1% in 2011 to 61% in 2015), while utilization of RYGB (68% to 32%) and LAGB (31% to 1%) decreased. Length of stay (LOS) was highest after RYGB (2.54 days), and lowest after LAGB (1.32 days). LOS decreased from 2.23 days in 2011 to 2.12 days in 2015. Thirty‐day readmissions were 8.24% for the disabled, 5.5% for the elderly, 12.8% with ESRD. Odds of readmission increased with black race, higher body mass index (BMI), and RYGB. Readmission decreased from 8% in 2011 to 7% in 2015. Thirty‐day mortality was 0.22% in the disabled, and 0.28% in the elderly. Odds of 30‐day mortality increased among men, those with higher BMI, some comorbidities, and those who underwent RYGB. Cost of SG decreased while cost of RYGB increased.

Conclusions

Among the Medicare population, an increase in SG while a decrease in RYGB and LAGB utilization was noted from 2011–2015. Readmissions and cost have decreased, while mortality has remained low.

Chenodeoxycholic acid stimulates glucagon-like peptide-1 secretion in patients after Roux-en-Y gastric bypass

Postprandial secretion of glucagon‐like peptide‐1 (GLP‐1) is enhanced after Roux‐en‐Y gastric bypass (RYGB), but the precise molecular mechanisms explaining this remain poorly understood. Plasma concentrations of bile acids (BAs) increase after RYGB, and BAs may act as molecular enhancers of GLP‐1 secretion through activation of TGR5‐receptors. We aimed to evaluate GLP‐1 secretion after oral administration of the primary bile acid chenodeoxycholic acid (CDCA) and the secondary bile acid ursodeoxycholic acid (UDCA) (which are available for oral use) in RYGB‐operated participants. Eleven participants (BMI 29.1 ± 1.2, age 37.0 ± 3.2 years, time from RYGB 32.3 ± 1.1 months, weight loss after RYGB 37.0 ± 3.1 kg) were studied in a placebo‐controlled, crossover‐study. On three different days, participants ingested (1) placebo (water), (2) UDCA 750 mg, (3) CDCA 1250 mg (highest recommended doses). Oral intake of CDCA increased plasma concentrations of GLP‐1, C‐peptide, glucagon, peptide YY, neurotensin, total bile acids, and fibroblast growth factor 19 significantly compared with placebo (all P < 0.05 for peak and positive incremental area‐under‐the‐curve (piAUC)). All plasma hormone concentrations were unaffected by UDCA. Neither UDCA nor CDCA changed glucose, cholecystokinin or glucose‐dependent insulinotropic polypeptide (GIP) concentrations. In conclusion, our findings demonstrate that the primary bile acid chenodeoxycholic acid is able to enhance secretion of gut hormones when administered orally in RYGB‐operated patients—even in the absence of nutrients.

Changes of blood glucose and gastrointestinal hormones 4 months after Roux-en-Y gastric bypass surgery in Chinese obese type 2 diabetes patients with lower body mass index

Aims/Introduction

The goal of this study was to evaluate the effect of Roux‐en‐Y gastric bypass (RYGB) on hyperglycemia and gastrointestinal hormones in Chinese obese type 2 diabetic patients with body mass index (BMI) between 28 and 35 kg/m².

Materials and Methods

A total of eight obese type 2 diabetes patients with BMI 28–35 kg/m² who underwent RYGB and 10 obese normal glucose tolerance (NGT) patients with no surgery were identified. BMI and blood glucose on baseline, and 2–4 months postoperative, changes of glucagon‐like peptide‐1 (GLP‐1), glucose‐dependent insulinotropic polypeptide (GIP), peptide YY (PYY), and oxyntomodulin (OXM) were recorded. Efficacy of RYGB was defined by the percentage of excess weight loss (%EWL) and amelioration of type 2 diabetes.

Results

The %EWL was 53.00 ± 26.25% in 2 month and 63.65 ± 33.71% in 4 month. Glycated hemoglobin changed from 7.2 ± 1.0% preoperative to 6.2 ± 0.9% in 2 month and 6.3 ± 1.2% in 4 month postoperative. The improvement rate of type 2 diabetes 4 months after RYGB was 83.3%. After surgery, area under the curve (AUC) GLP‐1 120 increased with no significance. AUC PYY 120 changed from 10.37 ± 5.45 pmol/L/min preoperative to 22.19 ± 10.61 pmol/L/min in 2 month and 22.04 ± 7.73 pmol/L/min in 4 month postoperative. Postoperative AUC OXM 120 was also higher than that of the preoperative level. AUC GIP 120 decreased from 13.06 ± 8.45 pg/mL/min preoperative to 8.71 ± 3.28 pg/ml/min in 2 month and 6.88 ± 2.33 pg/mL/min in 4 month postoperative.

Conclusions

Roux‐en‐Y gastric bypass has a beneficial effect on weight loss and glucose metabolism in obese type 2 diabetes patients with lower BMI. Postoperative concentrations of GLP‐1, PYY and OXM increased, whereas GIP decreased.