Surgical approaches to the treatment of obesity

Cohort profile: study design and baseline characteristics of an observational longitudinal weight loss cohort and biorepository of patients undergoing sleeve gastrectomy in the USA

PURPOSE

We developed a comprehensive sleeve gastrectomy (SG) weight loss study cohort and biorepository to uncover mechanisms, biomarkers and predictive factors of weight loss, weight maintenance and amelioration of obesity-related comorbidities. For this purpose, we collected psychosocial, anthropometric, clinical data and a variety of samples pre-surgery, intraoperatively and 1.5, 3, 12 and 24 months post-surgery. For longer-term assessment, the collection of psychosocial and anthropometric data was extended to 10 years. Here, we present in-depth characterisation of the cohort and detailed overview of study procedures as a foundation for future analyses.

PARTICIPANTS

We consented 647 participants between June 2017 and March 2020 from two bariatric surgery clinics in New York City-one major urban hospital and one private hospital. Of 355 participants who provided baseline data, 300 underwent SG. Of these, 79% are females with an average age of 38 years, 68% are Hispanic, 20% are non-Hispanic Black and 11% are non-Hispanic White.

FINDINGS TO DATE

We collected intraoperative adipose and stomach tissues from 282 patients and biosamples (blood, urine, saliva, stool) from 245 patients at 1.5 months, 238 at 3 month, 218 at 12 months and 180 at 24 months post-surgery. We are currently collecting anthropometric and psychosocial data annually until 10 years post-surgery. Data analysis is currently underway.

FUTURE PLANS

Our future research will explore the variability in weight loss outcomes observed in our cohort, particularly among Black and Hispanic patients in comparison to their White counterparts. We will identify social determinants of health, metabolic factors and other variables that may predict weight loss success, weight maintenance and remission of obesity-related comorbidities. Additionally, we plan to leverage our biorepository for collaborative research studies. We will complete long-term follow-up data by December 2031. We plan to apply for funding to expand biosample collection through year 10 to provide insights into the mechanisms of long-term weight maintenance.

Non-invasive mapping of brown adipose tissue activity with magnetic resonance imaging

Thermogenic brown adipose tissue (BAT) has a positive impact on whole-body metabolism. However, in vivo mapping of BAT activity typically relies on techniques involving ionizing radiation, such as [18F]fluorodeoxyglucose ([18F]FDG) positron emission tomography (PET) and computed tomography (CT). Here we report a noninvasive metabolic magnetic resonance imaging (MRI) approach based on creatine chemical exchange saturation transfer (Cr-CEST) contrast to assess in vivo BAT activity in rodents and humans. In male rats, a single dose of the β3-adrenoceptor agonist (CL 316,243) or norepinephrine, as well as cold exposure, triggered a robust elevation of the Cr-CEST MRI signal, which was consistent with the [18F]FDG PET and CT data and 1H nuclear magnetic resonance measurements of creatine concentration in BAT. We further show that Cr-CEST MRI detects cold-stimulated BAT activation in humans (both males and females) using a 3T clinical scanner, with data-matching results from [18F]FDG PET and CT measurements. This study establishes Cr-CEST MRI as a promising noninvasive and radiation-free approach for in vivo mapping of BAT activity.

Roux-en-Y gastric bypass in a transgender patient: a case report

The frequency of transgender individuals seeking gender affirming care is increasing over the last decade. Transgender patients suffer from obesity and psychiatric illness at elevated levels compared with the general population. A 54-year-old male-to-female transition patient presented with morbid obesity, hyperlipidaemia, and weight gain 2 years after their gender-transition and hormonal therapy. She received a Roux-en-Y gastric bypass (RYGB). At 7 months postoperatively, the patient has experienced 49% excess body weight loss, her body dissatisfaction had resolved and has completed further plastic surgery. The RYGB is an effective method for weight loss as well as benefits from cardiovascular disease, cancer, metabolic related conditions, and psychosocial wellbeing. Holistic treatment in conjunction with dietetic and psychology services can help maintain long-term weight management. Bariatric surgery combined with a multidisciplinary care team addressing medical and psychiatric concerns is integral to achieving and maintaining weight loss and gender identity.

Efficacy and safety of endoscopic sleeve gastroplasty and laparoscopic sleeve gastrectomy with 12+ months of adjuvant multidisciplinary support

Background

The laparoscopic sleeve gastrectomy (LSG) and the incisionless endoscopic sleeve gastroplasty (ESG) weight loss procedures require further investigation of their efficacy, safety and patient-centered outcomes in the Australian setting.

Methods

The aim was to examine the 6- and 12-month weight loss efficacy, safety, and weight-related quality of life (QoL) of adults with obesity who received the ESG or LSG bariatric procedure with 12+ months of adjuvant multidisciplinary pre- and postprocedural support. Data were from a two-arm prospective cohort study that followed patients from baseline to 12-months postprocedure from a medical center in Queensland. Percent excess weight loss (%EWL) was the primary outcome. Secondary outcomes were body composition (fat mass, fat-free mass, android:gynoid ratio, bone mineral content) via dual energy X-ray absorptiometry, weight-related QoL, lipid, glycemic, and hepatic biochemistry, and adverse events.

Results

16 ESG (19% attrition; 81.2% female; aged:41.4 (SD: 10.4) years; BMI: 35.5 (SD: 5.2) kg/m²) and 45 LSG (9% attrition; 84.4% female; aged:40.4 (SD: 9.0) years; BMI: 40.7 (SD: 5.6) kg/m²) participants were recruited. At 12-months postprocedure, ESG %EWL was 57% (SD: 32%; p < 0.01) and LSG %EWL was 79% (SD: 24%; p < 0.001). ESG and LSG cohorts improved QoL (19.8% in ESG [p > 0.05]; 48.1% in LSG [p < 0.05]), liver function (AST: − 4.4 U/L in ESG [p < 0.05]; − 2.7 U/L in LSG [p < 0.05]), HbA1c (− 0.5% in ESG [p < 0.05]; − 0.1% in LSG [p < 0.05]) and triglycerides (− 0.6 mmol/L in ESG [p > 0.05]; − 0.4 mmol/L in LSG [P < 0.05]) at 12-months. Both cohorts reduced fat mass (p < 0.05). The ESG maintained but LSG decreased fat-free mass at 6-months (p < 0.05); and both cohorts lost fat-free mass at 12-months (p < 0.05). There were no adverse events directly related to the procedure. The ESG reported 25% mild-moderate adverse events possibly related to the procedure, and the LSG reported 27% mild-severe adverse events possibly related to the procedure.

Conclusions

In this setting, the ESG and LSG were safe and effective weight loss treatments for obese adults alongside multidisciplinary support. Patients who elected the ESG maintained fat-free mass at 6-months but both cohorts lost fat-free mass at 12-months postprocedure. Patients who elected the LSG had large and significant improvements to weight-related quality of life. Further well-powered studies are required to confirm these findings.

Trial registration

This study was registered prospectively at the Australia New Zealand Clinical Trials Registry on 06/03/2018, Registration Number ACTRN12618000337279.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12875-022-01629-7.

Inflammasome activation as a link between obesity and thyroid disorders: Implications for an integrated clinical management

Obesity is strongly associated with chronic low-grade inflammation. Obese patients have an increased risk to develop thyroid autoimmunity and to became hypothyroid, suggesting a pathogenetic link between obesity, inflammation and autoimmunity. Moreover, type 2 diabetes and dyslipidemia, also characterized by low-grade inflammation, were recently associated with more aggressive forms of Graves' ophthalmopathy. The association between obesity and autoimmune thyroid disorders may also go in the opposite direction, as treating autoimmune hyper and hypothyroidism can lead to weight gain. In addition, restoration of euthyroidism by L-T4 replacement therapy is more challenging in obese athyreotic patients, as it is difficult to maintain thyrotropin stimulation hormone (TSH) values within the normal range. Intriguingly, pro-inflammatory cytokines decrease in obese patients after bariatric surgery along with TSH levels. Moreover, the risk of thyroid cancer is increased in patients with thyroid autoimmune disorders, and is also related to the degree of obesity and inflammation. Molecular studies have shown a relationship between the low-grade inflammation of obesity and the activity of intracellular multiprotein complexes typical of immune cells (inflammasomes). We will now highlight some clinical implications of inflammasome activation in the relationship between obesity and thyroid disease.

A comparative study of eating behaviours within and between conventional metabolic (bariatric) surgery procedures

AIMS AND OBJECTIVES

To compare eating behaviours within and between gastric bypass, sleeve gastrectomy and gastric band procedures and to investigate associations between eating behaviours and body weight.

BACKGROUND

Eating behaviours are subjective constructs representing physiological need and the hedonic need to eat. After metabolic surgery, eating behaviours have been observed to change. Little is known about whether eating behaviour change differs according to the metabolic procedure performed.

DESIGN

Adults (n = 204) with severe obesity from three countries were followed 1 year after metabolic surgical procedures (n = 121).

METHODS

We measured eating behaviours using the Three-Factor Eating Questionnaire and used linear mixed models to compare eating behaviours within and between three procedure groups. We complied with the STROBE checklist for reporting observational studies.

RESULTS

Within groups, there were statistically significant increases in restraint and decreases in disinhibition and hunger. Between groups, we observed differences in disinhibition associated with the band procedure. There were no significant differences between any group for body weight or body mass index a year post-surgery. Disinhibition was the only eating behaviour associated with body weight, body mass index and the per cent of weight loss.

CONCLUSIONS

Eating behaviours in adults with severe obesity who underwent any of the three metabolic procedures were associated with eating behaviour change 1 year post-surgery. Disinhibition was the only eating behaviour that was associated with body weight.

RELEVANCE TO CLINICAL PRACTICE

Irrespective of the procedure, we found participants had a statistically significant increase in restraint and decreases in disinhibition and hunger 1 year post-surgery. Despite the significant reduction in disinhibition within the band group, this behaviour was more pronounced post-surgery compared with other groups. Although the reduction in hunger showed the greatest change, it was not associated with weight outcomes. This is relevant clinical knowledge for nurses who support bariatric surgical patients.

Effect of a multidisciplinary rehabilitation program for patients receiving weight management interventions on eating behaviours and health-related quality of life

The rapid rise in obesity prevalence is life-style related and tackling this problem requires a pro-active multi-faceted approach to management. A private health care provider in Melbourne, Australia, developed a multidisciplinary rehabilitation program for patients who had undergone bariatric surgery or receiving pharmacological weight loss treatments. The study aim was to assess the programs' effect on patients' quality of life, mental well-being, and eating behaviours.

METHODS

A prospective, observational, before and after study design was used. A total of 54 patients, 27 who had bariatric surgery and 27 receiving pharmacotherapy participated. Outcome measures were: change in weight and BMI, intuitive eating scale, impact of weight on quality of life scale and the depression, anxiety and stress scale.

RESULTS

Both medical and surgical patients reported improvements in their health-related quality of life and eating behaviours. Despite this, at program completion 71.4% of patients who had bariatric surgery reported severe anxiety and 52.4% severe stress levels.

CONCLUSION

Participation in a rehabilitation program that provided patients with peer support and access to expert advice supported patients to make healthy eating choices and improved their quality of life. The high prevalence of stress and anxiety related symptoms highlights the need to provide individuals who have undergone bariatric surgery with ongoing mental health support.

The Skeletal Consequences of Bariatric Surgery

PURPOSE OF REVIEW

This review outlines the recent findings regarding the impact of bariatric surgery on bone. It explores potential mechanisms for skeletal changes following bariatric surgery and strategies for management.

RECENT FINDINGS

Bone loss following bariatric surgery is multifactorial. Probable mechanisms include skeletal unloading, abnormalities in calciotropic hormones, and changes in gut hormones. Skeletal changes that occur after bariatric surgery are specific to procedure type and persist for several years post-operatively. Studies suggest that while bone loss begins early, fracture risk may be increased later in the post-operative course, particularly after Roux-en-Y gastric bypass (RYGB). Further research is needed to assess the extent to which skeletal changes following bariatric surgery result in fragility. Current management should be geared toward prevention of bone loss, correction of nutritional deficiencies, and incorporation of weight bearing exercise. Pharmacologic treatment should be considered for high-risk patients.

Sympathetic activity in obesity: a brief review of methods and supportive data

The increase in the prevalence of obesity and the concomitant rise in obesity-related illness have led to substantial pressure on health care systems throughout the world. While the combination of reduced exercise, increased sedentary time, poor diet, and genetic predisposition is undoubtedly pivotal in generating obesity and increasing disease risk, a large body of work indicates that the sympathetic nervous system (SNS) contributes to obesity-related disease development and progression. In obesity, sympathetic nervous activity is regionalized, with activity in some outflows being particularly sensitive to the obese state, whereas other outflows, or responses to stimuli, may be blunted, thereby making the assessment of sympathetic nervous activation in the clinical setting difficult. Isotope dilution methods and direct nerve recording techniques have been developed and utilized in clinical research, demonstrating that in obesity there is preferential activation of the muscle vasoconstrictor and renal sympathetic outflows. With weight loss, sympathetic activity is reduced. Importantly, sympathetic nervous activity is associated with end-organ dysfunction and changes in sympathetic activation that accompany weight loss are often reflected in an improvement of end-organ function. Whether targeting the SNS directly improves obesity-related illness remains unknown, but merits further attention.

Serum IGF-binding protein 2 (IGFBP-2) concentrations change early after gastric bypass bariatric surgery revealing a possible marker of leptin sensitivity in obese subjects

PURPOSE

Expression of IGFBP-2 in mice is regulated by leptin. Over-expression of IGFBP-2 is associated with reduced caloric intake and resistance to weight gain. Hormonal variations contributing to weight loss occur very early after bariatric surgery but have not been fully elucidated. We evaluated IGFBP-2 serum changes after bariatric surgery and their relationship with leptin variations to test the hypothesis that an increase of leptin sensitivity may explain some of the effects of gastric bypass.

METHODS

This is a historical prospective study. Fifty-one obese patients (41 women e 10 men), 9 non-obese surgical controls and 41 lean matched controls were studied. Serum IGFBP-2 and leptin were measured after bariatric bypass surgery at various time points up to 18 months, after non-bariatric laparoscopic surgery in a control group, and in lean matched controls.

RESULTS

Compared to lean controls, serum IGFBP-2 levels were lower in obese patients. After gastric bypass, IGFBP-2 significantly increased at 3 days and became normal before the occurrence of relevant changes in body weight, remaining stable up to 18 months after surgery. IGFBP-2/leptin ratio increased early after surgery and became normal after one year.

CONCLUSIONS

After gastric bypass, serum IGFBP-2 increases in a window of time when variations of hormones mediating the effects of bariatric surgery occur. Our results suggest that IGFBP-2, a leptin-regulated protein, may be an in-vivo marker of leptin action. If this is the case, an early improvement of leptin sensitivity might contribute to the anorectic effect of gastric bypass.

A meta-analysis of the effects of bariatric surgery on fracture risk

Bariatric surgery effectively treats morbid obesity. However, the negative effect of this surgery on the bone is concerning. The aim of this meta-analysis was to investigate the fracture risk associated with bariatric surgery in morbidly obese subjects. Relevant studies published from database inception to September 2017 were identified in PubMed, Embase and the Cochrane Library. The Newcastle-Ottawa Scale was used to evaluate the quality of the observational studies, and the Jadad score evaluated randomized controlled trials. Among the 1003 studies initially identified, five observational trials and one randomized controlled trial were eligible for inclusion. All studies included in the meta-analysis were considered high quality. Risk for any type of fracture was higher in the surgical group than in the non-surgical group (risk ratio [RR] 1.29, 95% confidence interval [CI] 1.18-1.42). After surgery, the fracture risk in non-vertebral sites was significantly increased, especially in the upper limbs (RR 1.42, 95% CI 1.08-1.87; and RR 1.68, 95% CI 1.15-2.45). Compared with those with restrictive procedures, subjects who underwent mixed restrictive and malabsorptive procedures tended to have an increased fracture risk (RR 1.54, 95% CI 0.96-2.46). To conclude, bariatric surgery is associated with an increased risk of total and non-vertebral fractures, especially in the upper limbs.

A history of obesity leaves an inflammatory fingerprint in liver and adipose tissue

BACKGROUND/OBJECTIVES

Dieting is a popular yet often ineffective way to lower body weight, as the majority of people regain most of their pre-dieting weights in a relatively short time. The underlying molecular mechanisms driving weight regain and the increased risk for metabolic disease are still incompletely understood. Here we investigate the molecular alterations inherited from a history of obesity.

METHODS

In our model, male high-fat diet (HFD)-fed obese C57BL/6J mice were switched to a low caloric chow diet, resulting in a decline of body weight to that of lean mice. We measured body composition, as well as metrics of glucose, insulin and lipid homeostasis. This was accompanied by histological and gene expression analysis of adipose tissue and liver to assess adipose tissue inflammation and hepatosteatosis. Moreover, acute hypothalamic response to (re-) exposure to HFD was assessed by qPCR.

RESULTS & CONCLUSIONS

Within 7 weeks after diet switch, most obesity-associated phenotypes, such as body mass, glucose intolerance and blood metabolite levels were reversed. However, hepatic inflammation, hepatic steatosis as well as hypertrophy and inflammation of perigonadal, but not subcutaneous, adipocytes persisted in formerly obese mice. Transcriptional profiling of liver and perigonadal fat revealed an upregulation of pathways associated with immune function and cellularity. Thus, we show that weight reduction leaves signs of inflammation in liver and perigonadal fat, indicating that persisting proinflammatory signals in liver and adipose tissue could contribute to an increased risk of formerly obese subjects to develop the metabolic syndrome upon recurring weight gain.

Health Outcomes and Explant Rates After Laparoscopic Adjustable Gastric Banding: A Phase 4, Multicenter Study over 5 Years

OBJECTIVE

This study aimed to evaluate the real-world safety and effectiveness of the LAP-BAND (Apollo Endosurgery Inc., Austin, Texas) adjustable gastric banding system (LBS) for 5 years following implantation.

METHODS

This prospective, longitudinal, phase 4, multicenter study involved 652 patients who had implantation of the LBS system. The primary outcome was the percentage of subjects who had LBS explant over 5 years. The secondary outcomes included the rate of reoperations, clinical and biochemical measures, and patient-reported outcome measures over 5 years.

RESULTS

The study cohort consisted of 79.3% females with a mean age of 44 years and a mean BMI of 45.4 kg/m² . The primary end point was met with an explant rate of 8.74% (95% CI: 6.6%-10.9%) at 5 years. The rates for completer-only analysis and imputed missing data analysis were 12.81% (95% CI: 9.7%-15.9%) and 12.85% (95% CI: 10.2%-15.5%), respectively. All were significantly lower than the historic rate of 39.4% (P < 0.001). There were 43 patients who required reoperations or revisions excluding explants (6.6%). A mean weight loss of 18.7% was maximally achieved by 2 years, and weight loss was maintained through to 5 years. All patient-reported outcomes showed improvement following LBS treatment throughout 5 years.

CONCLUSIONS

This study validates the long-term safety and effectiveness of LBS for the treatment of patients with obesity and its related conditions.

Effects of obesity treatments on bone mineral density, bone turnover and fracture risk in adults with overweight or obesity

BACKGROUND

New evidence suggests that obesity is deleterious for bone health, and obesity treatments could potentially exacerbate this.

MATERIALS AND METHODS

This narrative review, largely based on recent systematic reviews and meta-analyses, synthesizes the effects on bone of bariatric surgery, weight loss pharmaceuticals and dietary restriction.

RESULTS AND CONCLUSIONS

All three obesity treatments result in statistically significant reductions in hip bone mineral density (BMD) and increases in bone turnover relative to pre-treatment values, with the reductions in hip BMD being strongest for bariatric surgery, notably Roux-en Y gastric bypass (RYGB, 8%-11% of pre-surgical values) and weakest for dietary restriction (1%-1.5% of pre-treatment values). Weight loss pharmaceuticals (orlistat or the glucagon-like peptide-1 receptor agonist, liraglutide) induced no greater changes from pre-treatment values than control, despite greater weight loss. There is suggestive evidence that liraglutide may increase bone mineral content (BMC) - but not BMD - and reduce fracture risk, but more research is required to clarify this. All three obesity treatments have variable effects on spine BMD, probably due to greater measurement error at this site in obesity, suggesting that future research in this field could focus on hip rather than spine BMD. Various mechanisms have been proposed for BMD loss with obesity treatments, notably reduced nutritional intake/absorption and insufficient exercise, and these are potential avenues for protection against bone loss. However, a pressing outstanding question is whether this BMD reduction contributes to increased fracture risk, as has been observed after RYGB, and whether any such increase in fracture risk outweighs the risks of staying obese (unlikely).

The impact of Roux-en-Y gastric bypass surgery on normal metabolism in a porcine model

BACKGROUND

A growing body of literature on Roux-en-Y gastric bypass surgery (RYGB) has generated inconclusive results on the mechanism underlying the beneficial effects on weight loss and glycaemia, partially due to the problems of designing clinical studies with the appropriate controls. Moreover, RYGB is only performed in obese individuals, in whom metabolism is perturbed and not completely understood.

METHODS

In an attempt to isolate the effects of RYGB and its effects on normal metabolism, we investigated the effect of RYGB in lean pigs, using sham-operated pair-fed pigs as controls. Two weeks post-surgery, pigs were subjected to an intravenous glucose tolerance test (IVGTT) and circulating metabolites, hormones and lipids measured. Bile acid composition was profiled after extraction from blood, faeces and the gallbladder.

RESULTS

A similar weight development in both groups of pigs validated our experimental model. Despite similar changes in fasting insulin, RYGB-pigs had lower fasting glucose levels. During an IVGTT RYGB-pigs had higher insulin and lower glucose levels. VLDL and IDL were lower in RYGB- than in sham-pigs. RYGB-pigs had increased levels of most amino acids, including branched-chain amino acids, but these were more efficiently suppressed by glucose. Levels of bile acids in the gallbladder were higher, whereas plasma and faecal bile acid levels were lower in RYGB- than in sham-pigs.

CONCLUSION

In a lean model RYGB caused lower plasma lipid and bile acid levels, which were compensated for by increased plasma amino acids, suggesting a switch from lipid to protein metabolism during fasting in the immediate postoperative period.

Vitamin D alteration associated with obesity and bariatric surgery

Obesity and severe obesity constitute growing serious health problems reaching epidemic proportion in most countries. Interactions and relationships between obesity and bone tissue and its metabolism are complex but are more and more studied and recognized. Obesity is associated with an altered hormonal profile including particularly bone-regulating hormones like vitamin D. Bariatric surgery procedures, thanks to their effectiveness to achieve therapeutic endpoints for comorbidities associated with obesity, have had an increasing success. However, these surgeries by producing mechanical restriction and or malabsorption syndrome lead to nutritional deficiencies including vitamin D. In this review, we aim to (1) discuss the nutritional deficiency of vitamin D in the obese, (2) to summarize the different surgical options in bariatric surgery and to present the evidence concerning these procedures and their associated profile in vitamin D post-operative insufficiency, (3) to present the different recommendations in clinical practice to prevent or treat vitamin D deficiencies or insufficiencies in patients treated by bariatric surgery and finally to introduce emerging assumptions on the relationship between vitamin D, microbiota composition and circulating bile acids. Impact statement Obesity and severe obesity constitute growing serious health problems reaching epidemic proportion in most countries with a prevalence increasing from 6.4 in 1975 to 14.9% in 2014. This present review summarizes currently available data on vitamin D deficiencies in the obese population before and after bariatric surgery. The important evidence emerging from our evaluation confirms that obese patients are at risk of multiple nutritional deficiencies, especially vitamin D deficiency, before bariatric surgery. Our survey confirms that the precise role of the gut microbiome and its associated changes on the vitamin D metabolism after the different bariatric surgery procedures has not yet been studied. Furthermore, whether differences in the microbiota may alter the therapeutic responses to vitamin D is not known.

Recent Trends in Endoscopic Management of Obesity

Obesity remains a tremendous public health, clinical, and scientific challenge globally. Conventional approaches in the management of obesity offer limited potential for sustained weight loss. Bariatric surgery, although it represents the most effective weight loss treatment, has its own risks and is associated with substantial costs and limited patient applicability. Endoscopic weight loss procedures are considered as the major breakthrough in the management of obesity. Endoluminal interventions performed entirely through the gastrointestinal tract have evolved as a result of an attempt to replicate some of the anatomical features and the physiological effects of the traditional weight loss surgery while being reversible, less invasive, and more cost-effective. Restrictive procedures act to decrease gastric volume by space-occupying devices and/or by suturing or stapling techniques that alter gastric anatomy, whereas malabsorptive procedures tend to create malabsorption by preventing food contact with the duodenum and proximal jejunum. Other procedures act by influencing gastric function (gastric botulinum injections, gastric pacing, and vagal nerve blocking) or by gastric aspiration. It is important to underline that the majority of endoscopic weight loss procedures are still being evaluated and are not yet available routinely. Even though some of the techniques and devices that have recently emerged have demonstrated promising short-term results, evidence on their safety and long-term efficacy from well-designed and well-conducted research should be given before they can become an inherent part of everyday clinical practice. Given the rapid development of endoscopic weight loss procedures, this review considers the current state and recent trends in endoscopic management of obesity.

Type 2 Diabetes in the Elderly: Challenges in a Unique Patient Population

In the older patient population, rates of Type 2 Diabetes (T2D) and obesity are reaching epidemic proportions. In fact, older patients will soon constitute the majority of patients with T2D in most developed countries. The higher prevalence of T2D in older individuals is seen in both men and women and across racial and ethnic groups. However, certain ethnic groups are disproportionately affected and successful strategies must account for these fundamental differences. T2D in old age is associated with traditional diabetes-associated complications including micro- and macro vascular disease, but is also closely related to numerous other comorbidities including cognitive impairment, urinary incontinence, sarcopenia, and increased fall risk. An overall state of chronic inflammation and dysregulated immune system may underlie these increased risks; yet our understanding of immunometabolism during the aging process remains incomplete. In addition, optimal recognition and treatment of diabetes in the elderly is hampered by a lack of relevant, high-quality studies, as the majority of clinical trial data establishing risk profiles, glycemic targets, and therapeutic interventions for T2D are not applicable for large segments of the older patient population. Simply acknowledging this gap is inadequate. We need strong evidence-based data upon which to successfully identify diabetic patients and then intervene in ways that are targeted to specific individuals within a heterogeneous group of elderly patients with T2D.

Nutritional and Protein Deficiencies in the Short Term following Both Gastric Bypass and Gastric Banding

BACKGROUND

The number of morbidly obese patients undergoing bariatric surgery (BS) has increased dramatically in recent years. Therefore, monitoring food intake and its consequences in terms of nutritional status is necessary to prevent nutritional deficiencies. The aim of this study was to analyze the effect of food restriction on nutritional parameters in the short-term (≤3 months) period after BS in morbid obesity.

METHOD

In a prospective study, we followed 22 obese women who underwent Roux-en-Y gastric bypass (GBP) or adjustable gastric banding (AGB) at baseline (T0) and 1 (T1) and 3 (T3) months after surgery. We evaluated food intake, nutrient adequacy and serum concentrations of vitamins and minerals known to be at risk for deficiency following BS.

RESULTS

Before surgery, we observed suboptimal food intakes, leading to a risk of micronutrient deficiencies. Serum analysis confirmed nutritional deficiencies for iron and thiamine for 27 and 23% of the patients, respectively. The drastic energy and food reduction seen in the short term led to very low probabilities of adequacy for nutrients equivalent across both surgeries. Serum analysis demonstrated a continuous decrease in prealbumin during the follow-up, indicating mild protein depletion in 21 and 57% of GBP patients and 50 and 63% of AGB patients, respectively, at T1 and T3. Regarding vitamins and minerals, systematic supplementation after GBP prevented most nutritional deficiencies. By contrast, AGB patients, for whom there is no systematic supplementation, developed such deficiencies.

CONCLUSIONS

Our results suggest that cautious monitoring of protein intake after BS is mandatory. Furthermore, AGB patients might also benefit from systematic multivitamin and mineral supplementation at least in the short term.

Leg to leg bioelectrical impedance analysis of percentage fat mass in obese patients-Can it tell us more than we already know?

BACKGROUND

Bioelectrical impedance analysis (BIA) is well tolerated, inexpensive, and readily available, but can it be used to detect with clinical precision aberrant changes in the proportion of fat mass to fat-free mass during weight loss?

OBJECTIVES

To assess the variance in percentage body fat mass explained by the readily available inputs and assess residual variance provided by leg-to-leg BIA scales.

METHODS

Using cross-sectional data from a cohort of 665 patients of Indian ethnicity presenting for bariatric surgery, we examine the determinants of percentage body fat as provided by leg-to-leg output from Tanita SC-330 BIA scales.

RESULTS

Four input factors-sex, weight, height, and age-contributed to provide 92% and 95% explanation in output variance for percentage fat mass (%FM) and actual fat mass, respectively, in 665 patients. Body mass index alone explained 89% and 81% of variance in %FM output for women and men, respectively. Neither weight distribution, as indicated by waist and hip circumference or waist to hip ratio, nor plasma lipids or markers of glucose metabolism contributed additional variance in %FM when controlled for the 4 key inputs.

CONCLUSIONS

Simple, known input variables dominate the leg-to-leg BIA output of %FM, and this may compromise the detection of aberrant changes in %FM and fat-free mass with substantial weight loss. For clinical research, validated methods not largely dependent on known inputs should be used for evaluating changes in body composition after substantial weight loss.

Neuroendocrine adaptations to bariatric surgery

The global epidemic of obesity and its related disease in combination with robust physiological defence of intentional weight loss generates a pressing need for effective weight loss therapies. Bariatric surgery, which works very effectively at delivering substantial sustained weight loss, has been an enigma with respect to mechanism of action. Naive concepts of restriction and malabsorption do not explain the efficacy of the most commonly used bariatric procedures. This century has seen increased interest in unravelling the mystery of the mechanisms underlying surgery associated weight loss with a focus on integrative gastrointestinal (GI) physiology, gut-brain signalling, and beyond weight loss effects on metabolism. GI interventions, some very minor, can alter GI wall stretch and pressure receptors; a range of GI hormones affecting hunger and satiety; bile acid metabolism and signalling; the characteristics of GI microbiome; portal vein nutrient sensing; and circulating concentrations of amino acids. Understanding the mechanisms involved should present targets for less invasive effective therapies.

LAP-BAND for BMI 30-40: 5-year health outcomes from the multicenter pivotal study

BACKGROUND

We performed a 5-year multicenter study to evaluate the safety and effectiveness of the LAP-BAND System surgery (LBS) in patients with obesity with a body mass index (BMI) of 30-39.9 kg m(-)(2). This pivotal study was designed to support LBS application to the US Food and Drug Administration for broadening the indications for surgery and the lower BMI indication was approved with 1-year data in 2011, with the intention to complete the 5-year evaluation.

OBJECTIVES

To present broad health outcome data including weight change, patient reported outcomes, comorbidity change and complications during the 5-year study.

SETTING

The study was conducted at seven US private practice clinical trial sites.

METHODS

We enrolled 149 BMI 30-39.9 subjects into a 5-year, multicenter, longitudinal, prospective post-approval study. Data for those completing each time point are presented.

RESULTS

The predefined target of at least 30% excess weight loss was achieved by more than 76% of subjects by 1-year and at every year thereafter during the 5-year study. Mean percentage weight loss at 5 years was 15.9±12.4%. Sustained weight loss was accompanied by sustained improvement in generic and weight-specific quality of life, symptoms of depression and the prevalence of binge-eating disorder. The number of subjects with normal fasting triglyceride, high-density lipoprotein cholesterol, plasma glucose and HbA1c increased significantly between baseline and 5 years. Fifty-four months after LBS implantation, the rate of device explants without replacement was 5.4%; however, the rate of explants increased to 12.1% by month 60 owing to no cost-elective band removals offered to subjects at study exit. No deaths or unanticipated adverse device effects were reported.

CONCLUSIONS

The LBS is safe and effective for people with BMI 30-39.9 with demonstrated improvements in weight loss, comorbidities and quality of life, and with a low explant rate through 5 years following treatment.

Efficacy of laparoscopic sleeve gastrectomy and intensive medical management in obese patients with type 2 diabetes mellitus

BACKGROUND

There are a dearth of studies comparing laparoscopic sleeve gastrectomy (LSG) and intensive medical treatment (IMT) in obese type 2 diabetes mellitus (T2DM) patients. This study compares these modalities in terms of weight loss, metabolic parameters and quality of life (QOL) score.

METHODS

We evaluated the efficacy of LSG (n = 14) vs. IMT (n = 17) comprising of low calorie diet, exenatide, metformin and if required insulin detemir in 31 obese T2DM patients with BMI of 37.9 ± 5.3kg/m(2) and target HbA1c < 7 %. The mean (±SD) age of the patients was 49.6 ± 11.9 years and 74 % were women. The mean duration of diabetes was 8.5 ± 6.1 years and mean HbA1c was 8.6 ± 1.3 %. Primary end point was excess body weight loss (EBWL) at the final follow-up.

RESULTS

The mean duration of follow-up was 12.5 ± 5.0 (median 12) months. EBWL was 61.2 ± 17.6 % and 27.4 ± 23.6 % in LSG and IMT group respectively (p < 0.001). Glycemic outcomes improved in both with mean HbA1c of 6.6 ± 1.5 % in LSG and 7.1 ± 1.2 % in IMT group. In LSG group, there was resolution of diabetes and hypertension in 36 and 29 % of patients respectively while none in the IMT group. HOMA-IR, hsCRP, ghrelin and leptin decreased while adiponectin increased significantly in LSG compared to IMT group. QOL score improved in LSG as compared to IMT.

CONCLUSIONS

In obese T2DM patients, LSG is superior to IMT in terms of weight loss, resolution of comorbidities and QOL score.

The effects of gastrointestinal surgery on gut microbiota: potential contribution to improved insulin sensitivity

Bariatric surgery induces weight loss and major improvement in insulin-resistance through many mechanisms some of which are weight independent. It is now well acknowledged that gut microbiota is involved in the development of obesity and its related metabolic diseases, at least in mice. However, its causal role in human obesity progression remains to be demonstrated. Few studies now pointed at changes in microbiota composition after bariatric surgery, suggesting links between gut microbiota switch and metabolic improvement observed after surgery. As such new potential mechanisms of actions have been proposed. The aim of this review is to describe microbiota modifications observed after bariatric surgery and its potential relationships with improved insulin resistance. We here list some hypotheses, which will need further demonstration.

Roux-en-y gastric bypass attenuates hepatic mitochondrial dysfunction in mice with non-alcoholic steatohepatitis

OBJECTIVE

No therapy for non-alcoholic steatohepatitis (NASH) has been approved so far. Roux-en-y gastric bypass (RYGB) is emerging as a therapeutic option, although its effect on NASH and related hepatic molecular pathways is unclear from human studies. We studied the effect of RYGB on pre-existent NASH and hepatic mitochondrial dysfunction-a key player in NASH pathogenesis-in a novel diet-induced mouse model nicely mimicking human disease.

DESIGN

C57BL/6J mice were fed a high-fat high-sucrose diet (HF-HSD).

RESULTS

HF-HSD led to early obesity, insulin resistance and hypercholesterolaemia. HF-HSD consistently induced NASH (steatosis, hepatocyte ballooning and inflammation) with fibrosis already after 12-week feeding. NASH was accompanied by hepatic mitochondrial dysfunction, characterised by decreased mitochondrial respiratory chain (MRC) complex I and IV activity, ATP depletion, ultrastructural abnormalities, together with higher 4-hydroxynonenal (HNE) levels, increased uncoupling protein 2 (UCP2) and tumour necrosis factor-α (TNF-α) mRNA and free cholesterol accumulation. In our model of NASH and acquired mitochondrial dysfunction, RYGB induced sustained weight loss, improved insulin resistance and inhibited progression of NASH, with a marked reversal of fibrosis. In parallel, RYGB preserved hepatic MRC complex I activity, restored ATP levels, limited HNE production and decreased TNF-α mRNA.

CONCLUSIONS

Progression of NASH and NASH-related hepatic mitochondrial dysfunction can be prevented by RYGB. RYGB preserves respiratory chain complex activity, thereby restoring energy output, probably by limiting the amount of oxidative stress and TNF-α. These data suggest that modulation of hepatic mitochondrial function contributes to the favourable effect of RYBG on established NASH.

Haemostatic and fibrinolytic changes in obese subjects undergoing bariatric surgery: the effect of different surgical procedures

BACKGROUND

Little is known about effects of different bariatric surgery procedures on haemostatic and fibrinolytic parameters.

MATERIAL AND METHODS

Consecutive obese subjects undergoing gastric bypass (GBP) or sleeve gastrectomy (SG) were enrolled. In all patients, levels of haemostatic factors (FII, FVII, FVIII, FIX, FX, vWF, fibrinogen), fibrinolytic variables (PAI-1, t-PA and D-dimer) and natural anticoagulants (AT, protein C and protein S) were evaluated before and 2 months after surgery.

RESULTS

A total of 77 GBP and 79 SG subjects completed the study. At baseline no difference in coagulation parameters was found between the two groups. After both GBP and SG, subjects showed significant changes in haemostatic and fibrinolytic variables and in natural anticoagulant levels. The Δ% changes in FVII, FVIII, FIX, vWF, fibrinogen, D-dimer, protein C and protein S levels were significantly higher in subjects who underwent GBP than in those who underwent SG. Multivariate analysis confirmed that GBP was a predictor of higher Δ% changes in FVII (β=0.268, p=0.010), protein C (β=0.274, p=0.003) and protein S (β=0.297, p<0.001), but not in all the other variables. Following coagulation factor reduction, 31 subjects (25.9% of GBP and 13.9% of SG; p=0.044) showed overt FVII deficiency; protein C deficiency was reported by 34 subjects (32.5% of GBP vs 11.4% of SG, p=0.033) and protein S deficiency by 39 (37.6% of GBP vs 12.6% of SG, p=0.009). Multivariate analyses showed that GBP was associated with an increased risk of deficiency of FVII (OR: 3.64; 95% CI: 1.73-7.64, p=0.001), protein C (OR: 4.319; 95% CI: 1.33-13.9, p=0.015) and protein S (OR: 5.50; 95% CI: 1.71-17.7, p=0.004).

DISCUSSION

GBP is associated with an increased risk of post-operative deficiency in some vitamin K-dependent coagulation factors. Whereas such deficiency is too weak to cause bleeding, it is significant enough to increase the risk of thrombosis.

Nature, Nurture, and Expertise

Rather than investigating the extent to which training can improve performance under experimental conditions ('what could be'), we ask about the origins of expertise as it exists in the world ('what is'). We used the twin method to investigate the genetic and environmental origins of exceptional performance in reading, a skill that is a major focus of educational training in the early school years. Selecting reading experts as the top 5% from a sample of 10,000 12-year-olds twins assessed on a battery of reading tests, three findings stand out. First, we found that genetic factors account for more than half of the difference in performance between expert and normal readers. Second, our results suggest that reading expertise is the quantitative extreme of the same genetic and environmental factors that affect reading performance for normal readers. Third, growing up in the same family and attending the same schools account for less than a fifth of the difference between expert and normal readers. We discuss implications and interpretations ('what is inherited is DNA sequence variation'; 'the abnormal is normal'). Finally, although there is no necessary relationship between 'what is' and 'what could be', the most far-reaching issues about the acquisition of expertise lie at the interface between them ('the nature of nurture: from a passive model of imposed environments to an active model of shaped experience').

Clinical factors associated with weight loss outcomes after Roux-en-Y gastric bypass surgery

OBJECTIVE

Gastric bypass surgery is an effective therapy for extreme obesity. However, substantial variability in weight loss outcomes exists that remains largely unexplained. Our objective was to determine whether any commonly collected preoperative clinical variables were associated with weight loss following Roux-en-Y gastric bypass (RYGB) surgery.

METHODS

The analysis was based on a prospectively recruited observational cohort of 2,365 patients who underwent Roux-en-Y gastric bypass surgery from 2004 to 2009. Weight loss was stratified into three major phases, early (0-6 months), nadir, and long-term (>36 months). Multivariate regression models were constructed using a database of over 350 variables.

RESULTS

A total of 12-14 preoperative variables were independently associated (P < 0.05) with each of the temporal weight loss phases. Preoperative variables associated with poorer nadir and long-term weight loss included higher baseline BMI, higher preoperative weight loss, iron deficiency, use of any diabetes medication, nonuse of bupropion medication, no history of smoking, age >50 years, and the presence of fibrosis on liver biopsy.

CONCLUSIONS

Several variables previously associated with poorer weight loss after RYGB surgery including age, baseline BMI, and type 2 diabetes were replicated. Several others suggest possible clinical interventions for postoperative management of RYGB patients to improve weight loss outcomes.

Long-term outcomes of laparoscopic adjustable silicone gastric banding (LAGB) in moderately obese patients with and without co-morbidities

BACKGROUND

Overweight and obesity independently increase cardiovascular risk, while even modest weight loss can result in clinically significant improvements in cardiovascular risk and reduce long-term mortality. Lowering the body mass index (BMI) threshold for bariatric surgery to those with moderate obesity might be one way to lower the burden of this disease. The aim of this study was to evaluate the efficacy and safety of laparoscopic adjustable silicone gastric banding (LAGB) in moderately obese subjects with or without obesity-related co-morbidities.

METHODS

Thirty-four patients with BMI between 30 and 35 kg/m(2) (5 males/29 females, mean age 36 ± 10 years, mean preoperative weight 87.9 ± 7.1 kg, mean BMI 32.6 ± 1.6 kg/m(2) and mean percentage excess weight 48.7 ± 9 %) who underwent LAGB via pars flaccida between June 1, 2002 and August 31, 2010 were included. Good response was defined as BMI <30 kg/m(2) or percentage estimated weight loss (%EWL) >50. Poor response was defined as BMI >30 kg/m(2) or %EWL less than 50 after a minimum of 1 year.

RESULTS

Mean weight, BMI and %EWL were recorded at 1, 3, 5 and 7 years and were 77.4 ± 7.6, 69.9 ± 10.8, 70.9 ± 9.3 and 73.3 ± 12.0 kg; 28.8 ± 2.9, 26.4 ± 3.2, 26.5 ± 3.4 and 27.4 ± 5.0 kg/m(2); and 36 ± 23, 46.1 ± 33.8, 58.6 ± 31.5 and 45 ± 57, respectively (p < 0.01). Co-morbidities were diagnosed in 17/34 (50 %) patients at baseline and underwent remission or improvement in all cases after 1 year.

CONCLUSIONS

LAGB in a safe and effective procedure in patients with a BMI <35 kg/m(2).

Five-year weight loss experience of outpatients receiving laparoscopic adjustable gastric band surgery

BACKGROUND

This study evaluated the efficacy and safety of laparoscopic adjustable gastric banding (LAGB) in a large cohort of morbidly obese patients followed for up to 5 years.

METHODS

Morbidly obese patients, ≥ 16 years of age, who underwent LAGB surgery at the Surgical Weight Loss Clinic in Ontario, Canada, between May 2005 and January 2011 were eligible for this retrospective chart review. Electronic files were searched to identify all patients who met the inclusion/exclusion criteria. Demographics, weights at baseline and follow-up visits (up to 60 months following surgery), and post-operative complications were documented. As follow-up visits occurred at unevenly spaced intervals within and across patients, modeling methods were used to more accurately assess mean % weight loss (WL) and % excess weight loss (EWL) over time.

RESULTS

This study included 2,815 patients (82 % female, mean age 43 years, mean baseline BMI 44.6 kg/m(2)) followed for a mean of 21.8 ± 15.4 months. Complications developed in 238 patients (8.5 %), the most frequent being prolapse/slippage (4.2 %), tubing/access port problems (1.2 %), and explantation (1.2 %). Mean %WL and %EWL progressed continuously over the first 2.5 years post-LAGB, plateauing at 20 and 49 %, respectively, for up to 5 years of follow up. Factors associated with increased weight loss were time since surgery, greater baseline weight (excess weight), older age at time of surgery, and male gender.

CONCLUSIONS

Weight loss was maintained for up to 5 years in our population of patients who underwent LAGB for the treatment of morbid obesity.

Bone loss after bariatric surgery: causes, consequences, and management

Bariatric surgery is an effective and increasingly common treatment for severe obesity and its many comorbidities. The side-effects of bariatric surgery can include detrimental effects on bone and mineral metabolism. Bone disease in patients who have had bariatric surgery is affected by preoperative abnormalities in bone and mineral metabolism related to severe obesity. Changes that arise after bariatric surgery are specific to procedure type: the most pronounced abnormalities in calciotropic hormones and bone loss are noted after procedures that result in the most malabsorption. The most consistent site for bone loss after all bariatric procedures is at the hip. There are limitations of dual-energy x-ray absorptiometry technology in this population, including artefact introduced by adipose tissue itself. Bone loss after bariatric surgery is probably multifactorial. Proposed mechanisms include skeletal unloading, abnormalities in calciotropic hormones, and changes in gut hormones. Few data for fracture risk in the bariatric population are available, and this is a crucial area for additional research. Treatment should be geared toward correction of nutritional deficiencies and study of bone mineral density in high-risk patients. We explore the skeletal response to bariatric surgery, potential mechanisms for changes, and strategies for management.

Surgical management of obesity in patients with morbid obesity and nonalcoholic fatty liver disease

Most patients with severe complex obesity presenting for bariatric-metabolic surgery have nonalcoholic fatty liver disease (NAFLD). NAFLD is associated with central obesity, insulin resistance, type 2 diabetes, hypertension, and obesity-related dyslipidemia. Weight loss should be a primary therapy for NAFLD. However, evidence supporting intentional weight loss as a therapy for NAFLD is limited. Bariatric-metabolic surgery provides the most reliable method of achieving substantial sustained weight loss and the most commonly used procedures are associated with reduced steatosis and lobular inflammatory changes, but there are mixed reports regarding fibrosis. Surgery should complement treatment of obesity-related comorbidity, but not replace established therapy.

Single-incision laparoscopic sleeve gastrectomy versus multiport laparoscopic sleeve gastrectomy: analysis of 80 cases in a single center

BACKGROUND

Through efficacy and improved safety, multiport laparoscopic sleeve gastrectomy (LAPS-G) has emerged as an important and broadly available treatment option for people with severe and complex obesity. Because a single-incision laparoscopic sleeve gastrectomy (SILS-G) would be less invasive, we applied this novel surgical technique for a selected number of patients enrolled into our minimally invasive bariatric program.

SUBJECTS AND METHODS

A retrospective review of prospectively collected data from 80 morbidly obese patients who qualified for SILS-G or LAPS-G was performed from January 2011 to May 2012.

RESULTS

SILS-G and LAPS-G were performed in 40 patients, respectively. All patients were female. Mean age was 41 (range, 19-73) years (SILS-G, 37 [19-62] years; LAPS-G, 43 [24-73] years; P=not significant). Preoperative body mass index was 40.8 (35.1-45.0) kg/m(2) in the SILS-G group and 43.8 (35.0-47.8) kg/m(2) in the LAPS-G group (P=not significant). Total operative time was significantly lower in the SILS-G group (85±21 minutes) compared with the LAPS-G group (97±26 minutes) (P<.05). Median percentage excess weight loss was comparable in both groups (SILS-G, 57.2%; LAPS-G, 53.7%) at 6.6 months after surgery. Mean hospital stay was 5 days (SILS-G, 5 [4-24] days; LAPS-G, 6 [4-14] days; P=not significant). Complication rates were low in both groups: leakage, 2.5% in SILS-G and 0% in LAPS-G; bleeding, 2.5% in SILS-G and 2.5% in LAPS-G; and trocar-site hernia, 0% in both groups. Patients operated on with single-incision laparoscopy had a significantly better cosmetic outcome as assessed by a scar satisfaction assessment questionnaire (P<.01).

CONCLUSIONS

SILS-G is a feasible and safe operative procedure that leads to a significant reduction of total operative time compared with a multiport access procedure. Further potential benefits associated with single-incision laparoscopic surgery remain to be investigated objectively.

Eating disorder examination-questionnaire factor structure and construct validity in bariatric surgery candidates

BACKGROUND

The Eating Disorder Examination-Questionnaire (EDE-Q) is increasingly used in studies with bariatric surgery patients although little is known about psychometric properties of this self-report measure in this clinical group. The current study evaluated the factor structure and construct validity of the EDE-Q in bariatric surgery candidates.

METHODS

Participants were a consecutive series of 174 obese bariatric surgery candidates who completed the EDE-Q and a battery of behavioral and psychological measures.

RESULTS

Confirmatory factor analysis (CFA) revealed an inadequate fit for the original EDE-Q structure but revealed a good fit for an alternative structure suggested by recent research with obese samples. CFA supported a seven-item, three-factor structure; the three factors were interpreted as dietary restraint, shape/weight overvaluation, and body dissatisfaction. The three factors converged with other relevant collateral measures.

CONCLUSIONS

These factor analytic findings, which replicate recent findings from studies with diverse obese samples, demonstrated convergent validity. Implications of these findings for clinical assessment and research with bariatric surgery patients are discussed.

Two similar cases of internal hernia after laparoscopic Roux-en-Y gastric bypass surgery

Internal hernia after laparoscopic Roux-en-Y gastric bypass (LRYGB) surgery can lead to acute small bowel obstruction or chronic recurrent abdominal pain. We present two cases of internal hernias after antecolic antegastric LRYGB. Both patients presented to the emergency room with acute diffuse abdominal pain. Other than that, a physical examination and routine laboratory workup did not reveal any pathological finding. An abdominal CT was performed in both cases. It showed mesenteric torsion as a sign of internal hernia in one case, but remained inconclusive in the other patient. Immediate diagnostic laparoscopy was performed in both cases. Intraoperatively, both patients revealed an internal hernia, where the common channel herniated through the mesojejunal space. The conversion to upper median minilaparotomy was necessary for hernia reduction in both cases. No bowel resection was required and both patients recovered fully.

Adiponectin oligomers as potential indicators of adipose tissue improvement in obese subjects

OBJECTIVE

Adiponectin is an adipocytokine that exerts beneficial effects on obesity and related disorders by two receptors (ADIPORs). Adiponectin is produced as a monomer that circulates in serum as different oligomers. The oligomerization state and the tissue expression of adiponectin and ADIPORs are linked to its biological activities. In this study, the levels of total adiponectin and its oligomers were evaluated in relation to obesity and surgical weight loss. The expression of adiponectin and ADIPORs was analyzed in visceral and subcutaneous adipose tissues of obese patients.

DESIGN AND METHODS

In 25 obese patients and 44 age- and sex-matched controls, the serum levels of adiponectin and its oligomers were measured and compared by ELISA, western blotting, and gel filtration. The expression of adiponectin and ADIPORs in both adipose tissues was evaluated by real-time quantitative PCR and western blotting.

RESULTS

The amount of each adiponectin oligomer, including the monomer, increases after weight loss. The reduced circulating levels of adiponectin and its oligomers are not associated with the adipose tissue depot-specific expression of adiponectin and ADIPORs.

CONCLUSIONS

Our results suggest that in patients, adiposity is associated with the serum concentrations of adiponectin and its oligomers but not with adipose tissue depot-specific expression of adiponectin and ADIPORs. In particular, the increase in adiponectin monomer levels could probably be related to the improvement of the whole-body energy metabolism then being involved in the improvement of adipose tissue function after weight loss. This work indicates the importance of assessing the whole adiponectin oligomeric profile as further potential indicators of adipose tissue functions in obesity.

Role of the gastroenterologist in managing obesity

Obesity has become a major public health problem as a consequence of its prevalence, negative impact on morbidity, mortality and quality of life and its associated direct and indirect healthcare costs. The etiology of obesity is multifactorial and reflects complex interactions of genetic, neurohumoral, environmental, behavioral and possibly, microbial factors. Available treatments for obesity include diet and exercise, behavioral modification, medications and surgery. Gastroenterologists are becoming increasingly involved in the care of obese patients. Although much of this care has historically centered on the preoperative and postoperative care of the bariatric patient, gastroenterologists are also evaluating and managing a variety of gastrointestinal symptoms and disorders that occur more commonly among obese individuals and are increasingly involved in the primary treatment of obesity. In this review, the gastrointestinal symptoms and disorders that are associated with obesity will be reviewed, the gastrointestinal contribution to the pathogenesis of obesity will be described and the current treatment options of obesity and where the gastroenterologist typically plays a role in the management will be discussed.

Weight loss induced by Roux-en-Y gastric bypass but not laparoscopic adjustable gastric banding increases circulating bile acids

CONTEXT

It has been hypothesized that increased plasma bile acids (BAs) contribute to metabolic improvements after Roux-en-Y gastric bypass (RYGB) surgery by the G protein-coupled receptor TGR5-mediated effects on glucagon-like peptide-1 secretion and thyroid hormones.

OBJECTIVE

The objective of this study was to evaluate the importance of bariatric surgery-induced alterations in BA physiology on factors that regulate glucose homeostasis (insulin secretion and sensitivity) and energy metabolism (resting energy expenditure and thyroid hormone axis). DESIGN, PARTICIPANTS, INTERVENTION, AND MAIN OUTCOME MEASURE: Eighteen extremely obese subjects were studied before and after 20% weight loss, induced by either laparoscopic adjustable gastric banding (LAGB) (n = 10) or RYGB surgery (n = 8).

RESULTS

Plasma BAs more than doubled after RYGB [fasting: 1.08 (0.26-1.42) to 2.28 (1.59-3.28) μmol/L, P = .03; postprandial: 2.46 ± 1.59 to 6.00 ± 2.75 μmol/L, P = .01] but were either lower or did not change after LAGB [fasting: 1.80 (1.49-2.19) to 0.92 (0.73-1.15) μmol/L, P = .02; postprandial: 3.71 ± 2.61 to 2.82 ± 1.75 μmol/L, P = .14]. Skeletal muscle expression of TGR5 targets, Kir6.2 and cyclooxygenase IV, increased after RYGB but not LAGB. Surgery-induced changes in BAs were associated with increased peak postprandial plasma glucagon-like peptide-1 (r(2) = 0.509, P = .001) and decreased serum TSH (r(2) = 0.562, P < .001) but did not correlate with the change in insulin response to a meal (r(2) = 0.013, P = .658), insulin sensitivity (assessed as insulin stimulated glucose disposal during a hyperinsulinemic-euglycemic clamp procedure) (r(2) = 0.001, P = .995), or resting energy expenditure (r(2) = 0.004, P = .807).

CONCLUSIONS

Compared with LAGB, RYGB increases circulating BAs and TGR5 signaling, but this increase in BAs is not a significant predictor of changes in glucose homeostasis or energy metabolism.

Single-incision Laparoscopic Sleeve Gastrectomy

Laparoscopic sleeve gastrectomy has gained popularity and acceptance among bariatric surgeons, mainly as a result of its low morbidity and mortality. Single-incision laparoscopic surgery (SILS), the most recent development in minimally invasive surgery, allows operations to be carried out through only a single incision using special ports. To further minimize the trauma of access incisions, we applied the SIL sleeve gastrectomy on a selected number of patients enrolled into our minimally invasive bariatric program. Between June 2010 and May 2012, 40 consecutive female patients underwent SIL sleeve gastrectomy. All data (demographic, morphologic, operative, and follow-up data) were prospectively collected in a computerized data bank. All patients were female. Mean age was 37 years (range, 19 to 62 years), preoperative body mass index was 40.8 kg/m2 (range, 35.1 to 45.0 kg/m2), and excess weight loss was 57.2 per cent at 6.6 months after surgery. Total operative time was 85 ± 21 minutes and mean hospital stay was 5 days (range, 4 to 24 days). Of the patients, two (5%) sustained postoperative complications such as leakage from the suture line and hemorrhage one in each case. There was no trocar site hernia. SIL sleeve gastrectomy seems to be an effective surgical option for the treatment of morbid obesity. During the first 6 months after the operation, weight loss was excellent. These results are at present comparable to those of multiport sleeve gastrectomy. SIL sleeve gastrectomy is safe and feasible and can be performed without changing the existing principles of this procedure.

Efficacy of intragastric balloon in obese Egyptian patients and the value of extended liquid diet period in mounting the weight loss

Abstract Background: The surgical management of morbid obesity is faced by several challenges. Alternative therapeutic strategies could have an important role in the perioperative risk reduction. The BioEnterics(®) intragastric balloon (BIB) (Inamed Health, Santa Barbara, CA) has been described as being effective in weight reduction and is used as a bridge before bariatric surgery. This study examined the efficacy of BIB in obese Egyptian patients and the value of the extended low caloric liquid diet program in weight loss.

SUBJECTS AND METHODS

A retrospective review of a prospectively maintained bariatric database was conducted. Weight changes and complications data were analyzed. Indications for BIB placement were discussed.

RESULTS

Records of 55 patients (11 males and 44 females) were retrieved. The mean initial body mass index (BMI) was 45.3±11 kg/m(2). The mean of excess body weight percentage was 111.96±53.2%. Nausea was reported in 30 patients (54.5%). Epigastric discomfort was reported in 23 patients (41.8 %), and vomiting was reported in 27 patients (49.1%). Six patients (10.9%) had an early removal of the balloon, whereas 4 (7.2%) had delayed removal (more than 6 months). The mean excess weight loss percentage (EWL%) was 17.2%. There was significant reduction in patients' BMI from 45.3 to 38.3 kg/m(2) (P<.001). There was no significant correlation between the EWL% and the gender, age, or initial BMI. Two patients had second balloon insertions without complications. There was no significant difference in the EWL% between the 1-week liquid diet group and the extended (4-week) low caloric diet group.

CONCLUSIONS

The BIB is effective and safe in weight reduction in obese Egyptian patients. The impact of extended liquid dieting period is not significant.

Bariatric surgery, bone loss, obesity and possible mechanisms

Bariatric surgery remains the most effective treatment for severely obese patients. However, the potential long-term effects of bariatric surgical procedures on health, including bone health, are only partially understood. The goal of this review was to present data on the impact of bariatric surgery on bone metabolism and to analyse possible reasons for the loss of bone mass that frequently occurs after bariatric surgery. Such factors include nutritional deficiencies, rapid weight loss per se, effects of fat-derived adipokines and gut-derived appetite-regulatory hormones. However, the relative roles of these factors in skeletal regulation and the mechanisms by which they work are not yet fully defined. Our review was focussed on the complex relationship between body weight, fat mass and bone mass, as well as peripheral and central mediators potentially involved in the dual regulation of both energy and bone homeostasis. We also review the data on the inverse relationship between central obesity, bone marrow fat and osteoporosis. As the number of bariatric operations increases, it is imperative to recognize mechanisms responsible for bariatric surgery-induced bone loss, with careful monitoring of bone health including long-term fracture incidence in patients undergoing these procedures.

Bariatric surgery and the kidney-much benefit, but also potential harm

Bariatric surgery is increasingly performed on overweight individuals. A significant benefit with respect to cardiovascular (CV) events and survival has been documented. After weight loss, reduction of albuminuria/proteinuria is almost consistently seen; small studies documented retardation of the glomerular filtration rate (GFR) loss after bariatric surgery; reduction of blood pressure (BP) is less consistent. It has been known for a long time that the frequency of oxalate stones is increased after bariatric surgery. The main renal threat of hyperoxaluria is renal oxalosis, often irreversible, causing persisting renal failure. The causes are reduced oxalate binding by calcium due to saponification of calcium causing fat malabsorption, increased permeability for oxalate because of increased permeability of colon mucosa triggered by increased bile salts and reduced colonization of the colon by oxalobacter formigenes. These mechanisms are susceptible to treatment.