Werd Al-Najim

Psychological characteristics, eating behavior, and quality of life assessment of obese patients undergoing weight loss interventions

Background and Aims: Bariatric surgery is the most effective treatment for obesity. However, not all patients have similar weight loss following surgery and many researchers have attributed this to different pre-operative psychological, eating behavior, or quality-of-life factors. The aim of this study was to determine whether there are any differences in these factors between patients electing to have bariatric surgery compared to less invasive non-surgical weight loss treatments, between patients choosing a particular bariatric surgery procedure, and to identify whether these factors predict weight loss after bariatric surgery. Material and Methods: This was a prospective study of 90 patients undergoing gastric bypass, vertical sleeve gastrectomy, or adjustable gastric banding and 36 patients undergoing pharmacotherapy or lifestyle interventions. All patients completed seven multi-factorial psychological, eating behavior, and quality-of-life questionnaires prior to choosing their weight loss treatment. Questionnaire scores, baseline body mass index, and percent weight loss at 1 year after surgical interventions were recorded. Results and Conclusions: Surgical patients were younger, had a higher body mass index, and obesity had a higher impact on their quality of life than on non-surgical patients, but they did not differ in the majority of eating behavior and psychological parameters studied. Patients opting for adjustable gastric banding surgery were more anxious, depressed, and had more problems with energy levels than those choosing vertical sleeve gastrectomy, and more work problems compared to those undergoing gastric bypass. Weight loss after bariatric surgery was predicted by pre-operative scores of dietary restraint, disinhibition, and pre-surgery energy levels. The results of this study generate a number of hypotheses that can be explored in future studies and accelerate the development of personalized weight loss treatments.

The Effect of a Subcutaneous Infusion of GLP-1, OXM, and PYY on Energy Intake and Expenditure in Obese Volunteers

Background: Roux-en-Y gastric bypass (RYGB) surgery is currently the most effective treatment of obesity, although limited by availability and operative risk. The gut hormones Glucagon-like peptide-1 (GLP-1), Peptide YY (PYY), and Oxyntomodulin (OXM) are elevated postprandially after RYGB, which has been postulated to contribute to its metabolic benefits. Objective: We hypothesized that infusion of the three gut hormones to achieve levels similar to those encountered postprandially in RYGB patients might be effective in suppressing appetite. The aim of this study was to investigate the effect of a continuous infusion of GLP-1, OXM, and PYY (GOP) on energy intake and expenditure in obese volunteers. Methods: Obese volunteers were randomized to receive an infusion of GOP or placebo in a single-blinded, randomized, placebo-controlled crossover study for 10.5 hours a day. This was delivered subcutaneously using a pump device, allowing volunteers to remain ambulatory. Ad libitum food intake studies were performed during the infusion, and energy expenditure was measured using a ventilated hood calorimeter. Results: Postprandial levels of GLP-1, OXM, and PYY seen post RYGB were successfully matched using 4 pmol/kg/min, 4 pmol/kg/min, and 0.4 pmol/kg/min, respectively. This dose led to a mean reduction of 32% in food intake. No significant effects on resting energy expenditure were observed. Conclusion: This is, to our knowledge, the first time that an acute continuous subcutaneous infusion of GOP, replicating the postprandial levels observed after RYGB, is shown to be safe and effective in reducing food intake. This data suggests that triple hormone therapy might be a useful tool against obesity.

Food Intake and Eating Behavior After Bariatric Surgery

Obesity is an escalating global chronic disease. Bariatric surgery is a very efficacious treatment for obesity and its comorbidities. Alterations to gastrointestinal anatomy during bariatric surgery result in neurological and physiological changes affecting hypothalamic signaling, gut hormones, bile acids, and gut microbiota, which coalesce to exert a profound influence on eating behavior. A thorough understanding of the mechanisms underlying eating behavior is essential in the management of patients after bariatric surgery. Studies investigating candidate mechanisms have expanded dramatically in the last decade. Herein we review the proposed mechanisms governing changes in eating behavior, food intake, and body weight after bariatric surgery. Additive or synergistic effects of both conditioned and unconditioned factors likely account for the complete picture of changes in eating behavior. Considered application of strategies designed to support the underlying principles governing changes in eating behavior holds promise as a means of optimizing responses to surgery and long-term outcomes.

Shifts in Food Preferences After Bariatric Surgery: Observational Reports and Proposed Mechanisms

Purpose of ReviewBariatric surgery is currently the most effective treatment for obesity. Roux-en-Y gastric bypass (RYGB) is the most commonly performed bariatric procedure and results in long-term weight loss. Alterations in food preference and choices may contribute to the long-term benefits of RYGB. This manuscript reviews the available literature documenting changes in food preference in both humans and experimental animals after RYGB and discusses the current theory on the underlying mechanisms involved.Recent FindingsObesity is associated with an increased preference for sweet and high-fat foods, and the most consistent evidence has been the shift away from these calorie-dense foods in both animal and human studies after RYGB. Self-reporting is the most common method used to record food preferences in humans, while more direct approaches have been used in animal work. This methodological heterogeneity may give rise to inconsistent findings.SummaryFuture studies in humans should focus on direct measures to permit corroboration of mechanistic insights gained from animal studies.

Integrated insights into the role of alpha-melanocyte stimulatory hormone in the control of food intake and glycaemia

HighlightsAmbient plasma glucose serves as an inductive signal for the regulated release of pituitary &agr;‐MSH into the bloodstream.Direct effects of &agr;‐MSH in skeletal muscle improve glucose clearance in pre‐clinical models.Skeletal muscle MC5R signalling as a novel target for anti‐hyperglycaemic agent development. ABSTRACT Identifying peptide hormones with multipotent actions on both weight and glycaemia can have a significant impact on therapeutic options in the treatment of obesity and diabetes. This has been exemplified by recent advances involving pharmacological exploitation of glucagon‐like peptide 1 biology. Herein, we summarise evidence supporting the potential candidacy in this light of alpha‐melanocyte stimulatory hormone, an endogenous peptide hormone and a breakdown product of the neuropeptide pro‐opiomelanocortin. We reference its well described central actions in the control of food intake and moreover highlight new data pointing to an important role for this peptide hormone in the periphery, in relation to glycaemic control.

Current and emerging pharmacotherapy for prediabetes: are we moving forward?

ABSTRACT Introduction: Prediabetes is a state wherein blood glucose levels are above normal but below the diagnostic threshold for diabetes. Seventy percent of patients with prediabetes develop type 2 diabetes in their lifetime. Despite this, prediabetes frequently goes undiagnosed. Areas covered: This review focuses on the pharmacological treatment of prediabetes and the prevention of progression to diabetes. A literature search was carried out on PubMed and Embase to review randomized controlled trials examining treatment of prediabetes. Emerging pharmacological therapies with potential benefit are discussed. Expert opinion: Lifestyle intervention is the cornerstone for preventing progression to diabetes, but metformin remains the first line pharmacological intervention. There appears to be minimal additive effect of combining metformin with lifestyle changes. It would be interesting to assess whether using combination pharmacological approaches plus or minus lifestyle interventions have any additive benefit. Despite the good level of evidence available, the penetrance of any interventions remains very low in part due to the prodromal categorization of the prediabetic state.

A randomised controlled trial of a duodenal-jejunal bypass sleeve device (EndoBarrier) compared with standard medical therapy for the management of obese subjects with type 2 diabetes mellitus

Introduction The prevalence of obesity and obesity-related diseases, including type 2 diabetes mellitus (T2DM), is increasing. Exclusion of the foregut, as occurs in Roux-en-Y gastric bypass, has a key role in the metabolic improvements that occur following bariatric surgery, which are independent of weight loss. Endoscopically placed duodenal-jejunal bypass sleeve devices, such as the EndoBarrier (GI Dynamics, Lexington, Massachusetts, USA), have been designed to create an impermeable barrier between chyme exiting the stomach and the mucosa of the duodenum and proximal jejunum. The non-surgical and reversible nature of these devices represents an attractive therapeutic option for patients with obesity and T2DM by potentially improving glycaemic control and reducing their weight. Methods and analysis In this multicentre, randomised, controlled, non-blinded trial, male and female patients aged 18–65 years with a body mass index 30–50 kg/m2 and inadequately controlled T2DM on oral antihyperglycaemic medications (glycosylated haemoglobin (HbA1c) 58–97 mmol/mol) will be randomised in a 1:1 ratio to receive either the EndoBarrier device (n=80) for 12 months or conventional medical therapy, diet and exercise (n=80). The primary outcome measure will be a reduction in HbA1c by 20% at 12 months. Secondary outcome measures will include percentage weight loss, change in cardiovascular risk factors and medications, quality of life, cost, quality-adjusted life years accrued and adverse events. Three additional subgroups will investigate the mechanisms behind the effect of the EndoBarrier device, looking at changes in gut hormones, metabolites, bile acids, microbiome, food hedonics and preferences, taste, brain reward system responses to food, eating and addictive behaviours, body fat content, insulin sensitivity, and intestinal tissue gene expression. Trial registration number ISRCTN30845205, ClinicalTrials.gov Identifier NCT02459561.