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Concept: Bariatrics


Severe obesity affects 4% to 6% of US youth and is increasing in prevalence. Bariatric surgery for the treatment of adolescents with severe obesity is becoming more common, but data on cost-effectiveness are limited.

Concepts: Obesity, Overweight, Weight loss, Bariatric surgery, Laparoscopic surgery, Gastric bypass surgery, Bariatrics, Adjustable gastric band


OBJECTIVES To analyze the effect of laparoscopic sleeve gastrectomy (LSG) on patients with gastroesophageal reflux disease (GERD) and to compare the results of LSG vs gastric bypass (GB) among patients with known GERD. DESIGN, SETTING, AND PATIENTS We performed a retrospective review of the Bariatric Outcomes Longitudinal Database from January 1, 2007, through December 31, 2010, including inpatient and all outpatient follow-up data. We compared patients undergoing LSG with a concurrent cohort undergoing GB. MAIN OUTCOMES AND MEASURES Rates of improvement or worsening of GERD symptoms, development of new-onset GERD, and weight loss and complications. RESULTS A total of 4832 patients underwent LSG and 33 867 underwent GB, with preexisting GERD present in 44.5% of the LSG cohort and 50.4% of the GB cohort. Most LSG patients (84.1%) continued to have GERD symptoms postoperatively, with only 15.9% demonstrating GERD resolution. Of LSG patients who did not demonstrate preoperative GERD, 8.6% developed GERD postoperatively. In comparison, GB resolved GERD in most patients (62.8%) within 6 months postoperatively (P < .001). Among the LSG cohort, the presence of preoperative GERD was associated with increased postoperative complications (15.1% vs 10.6%), gastrointestinal adverse events (6.9% vs 3.6%), and increased need for revisional surgery (0.6% vs 0.3%) (all P < .05). The presence of GERD had no effect on weight loss for the GB cohort but was associated with decreased weight loss in the LSG group. CONCLUSIONS AND RELEVANCE Laparoscopic sleeve gastrectomy did not reliably relieve or improve GERD symptoms and induced GERD in some previously asymptomatic patients. Preoperative GERD was associated with worse outcomes and decreased weight loss with LSG and may represent a relative contraindication.

Concepts: Obesity, Gastroesophageal reflux disease, Bariatric surgery, Bariatrics


Rates of adolescent obesity and overweight are high. The offspring of overweight parents are at increased risk of becoming obese later in life. Investigating neural correlates of familial obesity risk and current overweight status in adolescence could help identify biomarkers that predict future obesity and that may serve as novel targets for obesity interventions.

Concepts: Cancer, Nutrition, Obesity, Prediction, Overweight, Adipose tissue, Bariatrics, ARIA Charts


Overweight and obesity in children is a global problem. Besides physical effects, obesity has harmful psychological effects on children.

Concepts: Cancer, Nutrition, Obesity, Mass, Body mass index, Intelligence quotient, Body shape, Bariatrics


Many obese subjects suffer from an increased hedonic drive to consume palatable foods, i.e., hedonic hunger, and often show unfavorable dietary habits. Here, we investigated changes in the hedonic hunger and dietary habits after Roux-en-Y gastric bypass (RYGB) surgery.

Concepts: Nutrition, Obesity, Bariatric surgery, Gastric bypass surgery, Bariatrics, Duodenum, Surgical procedures, Beriberi


Background  Roux-en-Y gastric bypass (RYGB) surgery is very effective in reducing excess body weight and improving glucose homeostasis in obese subjects. Changes in the pattern of gut hormone secretion are thought to play a major role, but the mechanisms leading to both changed hormone secretion and beneficial effects remain unclear. Specifically, it is not clear whether changes in the number of hormone-secreting enteroendocrine cells, or changes in the releasing stimuli, or both, are important. Methods  We estimated numbers of enteroendocrine cells after immunohistochemical staining in fixed tissue samples from rats at 10-11 months after RYGB. Key Results  Numbers of glucagon-like peptide-1 (GLP-1) (L-cells, co-expressing peptide YY (PYY)), cholecystokinin (CCK), neurotensin, and 5-HT-immunoreactive cells were significantly increased in the Roux and common limbs, but not the biliopancreatic limb in RYGB rats compared with sham-operated, obese rats fed high-fat diet, and chow-fed controls. This increase was mostly accounted for by general hyperplasia of all intestinal wall layers of the nutrient-perfused Roux and common limbs, and less to increased density of expression. The number of ghrelin cells in the bypassed stomach was not different among the three groups. Conclusions & Inferences  The findings suggest that the number of enteroendocrine cells increases passively as the gut adapts, and that the increased total number of L- and I-cells is likely to contribute to the higher circulating levels of GLP-1, PYY, and CCK, potentially leading to suppression of food intake and stimulation of insulin secretion. Whether changes in releasing stimuli also contribute to altered circulating levels will have to be determined in future studies.

Concepts: Nutrition, Insulin, Obesity, Bariatric surgery, Gastric bypass surgery, Bariatrics, Duodenum, Beriberi


Observational studies suggest that bariatric surgery is the most effective intervention for achieving a significant and durable weight loss. In patients with type 2 diabetes, such surgery is often associated with remission of their diabetes. The mechanism(s) by which surgeries such as Roux-en-Y Gastric Bypass (RYGB) leads to favorable effects on glucose metabolism remain unknown. RYGB is associated with altered secretion of enteroendocrine hormones, leading to the belief that these hormones contribute to the improvement in insulin secretion and action as well as satiation after this procedure. However, it is important to consider the not insignificant effects of caloric restriction and the mechanical changes to the upper gut in determining the outcomes of such surgery.

Concepts: Insulin, Diabetes mellitus, Obesity, Surgery, Bariatric surgery, Gastric bypass surgery, Bariatrics, Duodenum


INTRODUCTION: Obesity is a chronic disease associated with oxidative stress. Bariatric surgery for the treatment of obesity may affect biomarkers of oxidative stress. OBJECTIVES: The aim of the present study was to evaluate the effect of Roux-en-Y gastric bypass (RYGB) on blood markers of oxidative stress, such as vitamins C and E, β-carotene, reduced glutathione (GSH), catalase (CAT), ferric reducing antioxidant potential (FRAP), and thiobarbituric acid-reactive substances (TBARS). METHODS: A prospective controlled clinical trial was carried out. The participants were distributed into two groups: a control group (n=35), which was evaluated once, and a bariatric group (n=35), which was evaluated at baseline as well as 6, 12, and 24 months after surgery. RESULTS: After surgery, the BMI decreased from 47.05±1.46 to 30.53±1.14 kg/m (P<0.001), but 25.7% of the participants regained weight after 24 months. In relation to the baseline, postsurgery reductions were found in vitamin C (31.9±4.6%, P<0.001), β-carotene (360.7±368.3%, P<0.001), vitamin E (22.8±4.1%, P<0.001), GSH (6.6±5.2%, P=0.090), CAT (12.7±5.6%, P=0.029), and FRAP (1.2±3.8%, P=0.085) 2 years after RYGB. TBARS levels decreased after 12 months (71.6±2.9%, P<0.001) in relation to the baseline but increased by 195.0±28.2% between the 12th and the 24th month (P<0.001). CONCLUSION: The present findings show that oxidative stress returned 2 years after RYGB. Concentrations of vitamin C, β-carotene, GSH, CAT, and FRAP were decreased, whereas the concentration of TBARS decreased in the first year but increased in the following year, which may be partly explained by the imbalance between antioxidants and pro-oxidants.

Concepts: Antioxidant, Obesity, Oxidative stress, Glutathione, Vitamin C, Bariatric surgery, Gastric bypass surgery, Bariatrics



Rivaroxaban is a direct factor Xa inhibitor, which is rapidly absorbed in the upper gastrointestinal (GI) tract. In large trials, it has been shown to be effective and safe in VTE treatment. However, in these trials patients with morbid obesity were not reported and it is unknown if the standard dosage of 20 mg rivaroxaban is sufficient for bariatric patients, especially after bariatric surgery, which may impact the resorption of rivaroxaban. We report the case of a bariatric patient with high venous thromboembolism risk and instable INR after recent bariatric surgery, who was switched from Vitamin-K antagonists to rivaroxaban. After intake of 20 mg rivaroxaban, plasma concentration were repeatedly measured until 3 h after the second dose using a commercially available chromogenic aXa-assay. Furthermore, INR and aPTT were measured. Peak concentrations of 224.22 ng/ml were observed. After 6 h, plasma concentration decreased to 86.9 ng/ml and remained stable until 12 h (86.32 ng/ml). After 24 h, a trough level of 35.54 ng/ml was observed. The patients INR did immediately increase and remained significantly elevated throughout the day with a slow decrease. Since peak values of rivaroxaban plasma concentrations were in the expected range of published data, we conclude that resorption of rivaroxaban was immediate and not significantly impaired by bariatric surgery of the upper GI tract. Consequently, no dose adjustments seem to be necessary in this high-risk population.

Concepts: Obesity, Overweight, Warfarin, Weight loss, Bariatric surgery, Digestion, Gastric bypass surgery, Bariatrics