Weight regain after Roux-en-Y: a significant 20% complication related to PYY

Epigenetic Mechanisms of Obesity: Insights from Transgenic Animal Models

Obesity is a chronic disease with prevalence rates that have risen dramatically over the past four decades. This increase is not due to changes in the human genome but rather to environmental factors that promote maladaptive physiological responses. Emerging evidence suggests that external influences, such as high-fat diets, modify the epigenome-the interface between genes and the environment-leading to persistent alterations in energy homeostasis. This review explores the role of epigenetic mechanisms in obesity, emphasizing insights from transgenic animal models and clinical studies. Additionally, we discuss the evolution of obesity research from homeostatic to allostatic frameworks, highlighting key neuroendocrine regulators of energy balance.

A randomized, double-blind, placebo-controlled trial of weight loss using liraglutide 3.0 mg for weight recurrence after Roux-en-Y gastric bypass

BACKGROUND

Bariatric surgery, such as Roux-en-Y gastric bypass (RYGB) remains the gold standard for treating obesity. Most people regain weight from postsurgery nadir.

OBJECTIVES

Liraglutide 3.0 mg is approved for weight management. This study will examine the effects on liraglutide 3.0 mg on weight regain post-RYGB.

SETTING

University Hospital, United States.

METHODS

A 56-week, double-blind, placebo-controlled study was conducted in 132 subjects, who achieved ≥25% total body weight loss (TBWL) status-post-RYGB and regained ≥10% TBWL after reaching nadir weight (NW). Subjects 18-120 months post-RYGB were randomized to receive liraglutide 3.0 mg/d (n = 89) or placebo (n = 43) with lifestyle counseling regularly for 56 weeks. The co-primary endpoints were the proportion of subjects losing at least 5%, 10%, and 15% TBWL and achieving weight lower than their NW.

RESULTS

53.4% of the placebo group and 65% of the liraglutide group completed the trial due to Severe acute respiratory syndrome coronavirus 2 pandemic. The change in %TBWL from baseline to 56-weeks was -8.8 (8.5, -29.2 to 9.7) and 1.1 (3.5, -7.9 to 5.99) in the liraglutide and placebo groups, respectively. 76% and 17% of subjects achieved ≥5% TBWL at 56 weeks in the liraglutide and placebo groups, respectively; 51% and 26.0% of the liraglutide group achieved ≥10% and ≥15% TBWL, respectively. None of the placebo group lost ≥10% TBWL. Twenty-one percent of subjects receiving liraglutide surpassed postoperative NW. No subjects on placebo met this goal. Nonserious adverse events occurred in 41.6% of subjects on liraglutide. Serious adverse events (SAE) occurred less often on liraglutide.

CONCLUSIONS

Liraglutide was significantly more effective than placebo in treating weight regain that occurs post-RYGB without increased SAE.

Effects of once-weekly subcutaneous retatrutide on weight and metabolic markers: A systematic review and meta-analysis of randomized controlled trials

Aim

To assess the effects of once-weekly subcutaneous retatrutide on weight and metabolic markers and the occurrence of side effects in patients with overweight, obesity and/or type 2 diabetes (T2D).

Methods

PubMed, Embase, Cochrane Library, and ClinicalTrials.gov databases were systematically searched for placebo-controlled, randomized clinical trials (RCTs) published up until February 23, 2024. Weighted mean differences (WMDs) for continuous outcomes and risk ratios (RRs) for binary endpoints were computed, with 95 % confidence intervals (CIs).

Results

A total of three studies were included, comprising 640 patients, of whom 510 were prescribed retatrutide. Compared with placebo, retatrutide significantly reduced body weight (WMD -10.66 kg; 95 % CI -17.63, -3.69), body mass index (WMD -4.53 kg/m2; 95 % CI -7.51, -1.55), and waist circumference (WMD -6.61 cm; 95 % CI -13.17, -0.05). In addition, retatrutide significantly increased the proportion of patients who achieved a weight reduction of ≥5 % (RR 2.92; 95 % CI 2.17-3.93), ≥10 % (RR 9.32; 95 % CI 4.56-19.06), ≥15 % (RR 18.40; 95 % CI 6.00-56.42), and ≥20 % (RR 16.61; 95 % CI 4.17-66.12).

Conclusions

In this meta-analysis, the use of once-weekly subcutaneous retatrutide was associated with a significant reduction in body weight and improvement of metabolic markers in patients with overweight, obesity and/or T2D, compared with placebo, with an increase in non-severe gastrointestinal and hypersensitivity adverse events. Phase 3 RCTs are expected to shed further light on the efficacy and safety of once-weekly subcutaneous retatrutide over the long term.

Effects of circuit weight training by intensity on stress hormones and antioxidant capacity in high-school wrestlers

We aimed to investigate the effects of 8-week circuit weight training by intensity on blood stress hormones and antioxidant capacity in high-school wrestlers. This study involved 27 male wrestlers with >2 years of wrestling experience who were randomly assigned to either a low intensity (n=13) or a high-intensity circuit weight training group (n=14). The participants performed circuit weight training for 60 min per session, 3 times per week for 8 weeks. The low- and high-intensity circuit weight training exercises were performed at 50%-60% and 70%-80% of one-repetition maximum for 10 stations, respectively, and 8-15 repeated sessions per station were performed in order. No changes were observed in adrenocorticotropic hormone (ACTH), cortisol, epinephrine, and norepinephrine levels between the two training groups. When compared to levels before the training, ACTH and epinephrine levels decreased, whereas cortisol levels increased. However, no difference was observed in norepinephrine levels. Further, no differences were observed in malondialdehyde (MDA) and glutathione peroxidase (GPX) levels between the two groups. However, MDA and GPX levels were increased from those before training. Changes in superoxide dismutase levels were observed between the two groups, but the change was significant only in the high-intensity circuit weight training group. Long-term training did not increase lipid peroxidation, but increased the activity of antioxidant enzymes that defend against oxidative stress. The antioxidant defense system in tissues can be regulated by exercise intensity as well as physical training status.

Impact of Recurrent Weight Gain Thresholds on Comorbid Conditions Progression Following Laparoscopic Sleeve Gastrectomy

INTRODUCTION

Defining recurrent weight gain after metabolic bariatric surgery poses a significant challenge. Our study aimed to standardize recurrent weight gain measurements in patients undergoing laparoscopic sleeve gastrectomy (LSG) and ascertain its association with comorbidity progression.

METHODS

We conducted a retrospective data analysis on 122 patients who underwent LSG, tracking their progress over 2-7 years. Data on weight, blood pressure measurements, and laboratory tests were collected, focusing on the postoperative period to identify nadir weight, total weight loss, and recurrent weight gain.

RESULTS

Significant weight loss and comorbidity remission were noted, with diabetes, hypertension, and dyslipidemia showing substantial remission rates of 85.71%, 68.24%, and 85.37%, respectively. The median recurrent weight gain was 6.30 kg within 12 months of the nadir. Progression proportion of diabetes, hypertension, and dyslipidemia were 8.20%, 44.26%, and 40.98%, respectively. Hypertension progression was strongly associated with a recurrent weight gain ≥ 10 kg and ≥ 20% of maximum weight loss. Dyslipidemia progression was significantly correlated with recurrent weight gain ≥ 10 kg and ≥ 20% of maximum weight loss. Diabetes progression was significantly correlated with recurrent weight gain ≥ 10% of pre-surgery body weight and ≥ 25% of maximum weight loss. A ≥ 10% weight gain of maximum weight loss did not significantly impact the progression of these conditions.

CONCLUSION

Recurrent weight gain ≥ 20% of maximum weight loss can be treated as a specific threshold indicating comorbidity progression post-LSG. Standardizing the measurement of recurrent weight gain can help healthcare providers to implement targeted management strategies to optimize long-term health outcomes.

Pharmacological treatment of non-responders following bariatric surgery

Obesity is a complex chronic disease and requires a long-term multidisciplinary management. Even patients undergoing bariatric surgery, one the most effective treatments for obesity, can have insufficient weight loss (IWL) than expected (primary non responder) or weight regain (WR) after a successful primary procedure (secondary non responder). A poor response represents a challenge of bariatric surgery that can induce persistence or recurrence of obesity-related comorbidities, prejudicing benefits of surgery. Increasing evidence suggests that weight loss medications represent a useful strategy in obesity care also after bariatric surgery procedures. This narrative review summarizes the evidence concerning anti-obesity therapy in the management of no-responders to primary bariatric surgery. Available data on liraglutide (one randomized double-blind placebo-controlled trial, three prospective and three retrospective studies), naltrexone/bupropion (three retrospective studies), orlistat (one case control prospective and one retrospective studies) and topiramate and phentermine (five retrospective studies) have been considered. Available data suggest that weight loss medications could offer a significant adjunctive benefit to lifestyle and behavioral modifications in the life-long management of obesity. Newer treatment modalities including the use of anti-obesity drugs provide patients and healthcare providers with more options in the management of poor response after bariatric surgery.

Weight Regain after Metabolic Surgery: Beyond the Surgical Failure

Patients undergoing metabolic surgery have factors ranging from anatomo-surgical, endocrine metabolic, eating patterns and physical activity, mental health and psychological factors. Some of the latter can explain the possible pathophysiological neuroendocrine, metabolic, and adaptive mechanisms that cause the high prevalence of weight regain in postbariatric patients. Even metabolic surgery has proven to be effective in reducing excess weight in patients with obesity; some of them regain weight after this intervention. In this vein, several studies have been conducted to search factors and mechanisms involved in weight regain, to stablish strategies to manage this complication by combining metabolic surgery with either lifestyle changes, behavioral therapies, pharmacotherapy, endoscopic interventions, or finally, surgical revision. The aim of this revision is to describe certain aspects and mechanisms behind weight regain after metabolic surgery, along with preventive and therapeutic strategies for this complication.

Bariatric Surgery in Obesity: Metabolic Quality Analysis and Comparison of Surgical Options

Obesity is a constantly growing health problem which reduces quality of life and life expectancy. Bariatric surgery (BS) for obesity is considered when all other conservative treatment modalities have failed. Comparison of the multidisciplinary programs with BS regarding to the weight loss showed that substantial and durable weight reduction have been achieved only with bariatric surgical treatments. Although laparoscopic sleeve gastrectomy is the most popular BS, it has high long-term failure rates, and it is claimed that one of every three patients will undergo another bariatric procedure within a 10-year period. Although BS provides weight loss and improvement of metabolic comorbidities, in long-term follow-up, weight gain is observed in half of the patients, while decrease in bone mass and nutritional deficiencies occur in up to 90%. Moreover, despite significant weight loss, several psychological aspects of patients are worsened in comparison to preoperative levels. Nearly one-fifth of postoperative patients with "Loss-of-eating control" meet food addiction criteria. Therefore, the benefits of weight loss following bariatric procedures alone are still debated in terms of the proinflammatory and metabolic profile of obesity.

Weight loss trend after bariatric surgery in a population of obese patients

BACKGROUND AND AIMS

Bariatric Surgery (BS) is a therapeutic option in patients with severe obesity whose non-surgical techniques have failed. No work has previously explored trajectories of weight loss and how long this was maintained. Aim of study is to describe effect of BS and nutritional intervention on body weight trend in patients with obesity.

METHODS

792 patients who underwent BS from 1996 to 2021 were included. The Protocol provides Laparoscopic Sleeve Gastrectomy (LSG), Vertical Gastroplasty (VBG) and Roux-en-Y Gastric Bypass (GB). %Total Weight Loss (%TWL) and %Excess Weight Loss (%EWL) were evaluated in three cohort of patients. Cumulative incidence of clinical goal after surgery was calculated at two and five years after BS.

RESULTS

At two years of follow-up, average %TWL and %EWL were 31.2% (95% CI = 29.0-33.4%) and 71% (95% CI = 65.4-76.5%) for VBG, 34.7% (95% CI = 33.8-35.6%) and 78.0% (95% CI = 75.9-89.1%) for GB and 33.8% (95% CI = 32.5-35.1%) and 68.8% (95% CI = 66.1-71.6%) for LSG. At two years from surgery the cumulative incidence of clinical goal was 70.7% (95% CI = 59.1-79.1%) for VBG, 86.4% (95% CI = 82.4-89.6%) for GB and 83.4% (95% CI = 76.0-87.1%) for LSG. At five years from surgery, average % TWL and % EWL were 22.5% (95% CI = 10.2-34.8%) and 58.2% (95% CI = 28.4-88.1%) for VBG, 31.8% (95% CI = 30.2-33.3%) and 70.8% (95% CI = 67.5-74.1%) for GB and 29.5% (95% CI = 26.2-32.8%) and 62.0% (95% CI = 53.4-70.6%) for LSG respectively. At five years after having reached clinical goal the share of people who were able to maintain their weight was 49.5% (95% CI = 30.8-79.6%) for VBG, 69.5% (95% CI = 58.3-82.8%) for GB and 55.9% (95% CI = 42.1-74.3%) for LSG. The median time of clinical goal maintaining was 4.8 years for VBG (95% CI lower limit = 4.1), 6.6 years for GB (95% CI lower limit = 6.2) and 5.3 years for LSG (95% CI lower limit = 4.8).

CONCLUSIONS

Our work confirm effectiveness of BS in patients with obesity and show that who do not reach clinical goal within 2 years, hardly will reach it later and suggest necessity for a medium and long-term follow-up to prevent weight regain.

Peptide YY: A Paneth cell antimicrobial peptide that maintains Candida gut commensalism

The mammalian gut secretes a family of multifunctional peptides that affect appetite, intestinal secretions, and motility whereas others regulate the microbiota. We have found that peptide YY (PYY1-36), but not endocrine PYY3-36, acts as an antimicrobial peptide (AMP) expressed by gut epithelial paneth cells (PC). PC-PYY is packaged into secretory granules and is secreted into and retained by surface mucus, which optimizes PC-PYY activity. Although PC-PYY shows some antibacterial activity, it displays selective antifungal activity against virulent Candida albicans hyphae-but not the yeast form. PC-PYY is a cationic molecule that interacts with the anionic surfaces of fungal hyphae to cause membrane disruption and transcriptional reprogramming that selects for the yeast phenotype. Hence, PC-PYY is an antifungal AMP that contributes to the maintenance of gut fungal commensalism.

Weight Regain After Bariatric Surgery: Scope of the Problem, Causes, Prevention, and Treatment

PURPOSE OF REVIEW

Although bariatric surgery is the most effective treatment of severe obesity, a proportion of patients experience clinically significant weight regain (WR) with further out from surgery. The purpose of this review is to summarize the prevalence, predictors, and causes of weight regain.

RECENT FINDINGS

Estimating the prevalence of WR is limited by a lack of consensus on its definition. While anatomic failures such as dilated gastric fundus after sleeve gastrectomy and gastro-gastric fistula after Roux-en-Y gastric bypass can lead to WR, the most common causes appear to be dysregulated/maladaptive eating behaviors, lifestyle factors, and physiological compensatory mechanisms. To date, dietary, supportive, behavioral, and exercise interventions have not demonstrated a clinically meaningful impact on WR, and there is limited evidence for pharmacotherapy. Future studies should be aimed at better defining WR to begin to understand the etiologies. Additionally, there is a need for non-surgical interventions with demonstrated efficacy in rigorous randomized controlled trials for the prevention and reversal of WR after bariatric surgery.

Literature review on antiobesity medication use for metabolic and bariatric surgery patients from the American Society for Metabolic and Bariatric Surgery Clinical Issues Committee

The following literature search is in response to inquiries made to the American Society for Metabolic and Bariatric Surgery (ASMBS) regarding antiobesity medication (AOM) use in patients who are having or have already had metabolic and bariatric surgery (MBS). These recommendations are based on current clinical knowledge, expert opinion, and published peer-reviewed scientific evidence available at this time. This paper is not intended to establish a local, regional, or national standard of care. The paper will be revised in the future as additional evidence becomes available.

Gut microbiome: Linking together obesity, bariatric surgery and associated clinical outcomes under a single focus

Obesity is increasingly prevalent in the post-industrial era, with increased mortality rates. The gut microbiota has a central role in immunological, nutritional and metabolism mediated functions, and due to its multiplexity, it is considered an independent organ. Modern high-throughput sequencing techniques have allowed phylogenetic exploration and quantitative analyses of gut microbiome and improved our current understanding of the gut microbiota in health and disease. Its role in obesity and its changes following bariatric surgery have been highlighted in several studies. According to current literature, obesity is linked to a particular microbiota profile that grants the host an augmented potential for calorie release, while limited diversity of gut microbiome has also been observed. Moreover, bariatric surgery procedures represent effective interventions for sustained weight loss and restore a healthier microbiota, contributing to the observed fat mass reduction and lean mass increase. However, newer evidence has shown that gut microbiota is only partially recovered following bariatric surgery. Moreover, several targets including FGF15/19 (a gut-derived peptide), could be responsible for the favorable metabolic changes of bariatric surgery. More randomized controlled trials and larger prospective studies that include well-defined cohorts are required to better identify associations between gut microbiota, obesity, and bariatric surgery.

Appetite Changes in Weight Regain and Weight Maintenance After Roux-en-Y Gastric Bypass

PURPOSE

Roux-en-Y gastric bypass (RYGB) surgery produces significant weight loss. However, a number of patients experience weight regain years after surgery. Factors driving weight regain after surgical interventions are currently being explored. Our objective was to investigate appetite-related measures associated with weight regain after RYGB surgery.

MATERIALS AND METHODS

Using a cross-sectional design, 29 participants (49.6 ± 9.1 years of age; current BMI 32.4 ± 4.7 kg/m², 43.6 ± 8.9 months post-RYGB) were stratified into tertiles according to weight regain per month after nadir (weight maintenance (WM), n = 9; low weight regain (LWR), n = 10; and high weight regain (HWR), n = 10). The average weight regain was, by design, significantly different between the groups (WM = 2.2 ± 2.5 kg; LWR = 10.0 ± 3.4 kg; HWR = 14.9 ± 6.3 kg regained, p < 0.05). Appetite (visual analog scales), olfactory performance ("sniffin sticks"), eating behaviors (Three Factor Eating Questionnaire), food reward (Leeds Food Preference Questionnaire), and appetite-related hormones (ghrelin, PYY, GLP-1 and leptin) were measured fasting and in response to a standardized test meal.

RESULTS

Dietary restraint was significantly higher than clinical cutoffs in WM and LWR (p < 0.05). As expected, significant time effects were noted for ghrelin, PYY, and GLP-1, but there were no group differences.

CONCLUSION

The results suggest that appetite-related outcomes are similar across individuals who have maintained weight loss and experienced regain following RYGB.

Preoperative Weight Loss as a Predictor of Bariatric Surgery Postoperative Weight Loss and Complications

BACKGROUND

The association between preoperative weight loss and bariatric surgery outcomes remains unclear. We explored the utility of preoperative weight loss as a predictor of postoperative weight loss success. Additionally, we examined the association of preoperative weight loss with perioperative complication rates.

METHODS

Retrospective chart review of patients who underwent primary sleeve gastrectomy or primary Roux-en-Y gastric bypass for weight loss at a single institution between January 2003 and November 2017. Additional follow-up was obtained by a postoperative standardized patient questionnaire. Statistical analysis consisted of bivariate and multivariate logistic regression analysis.

RESULTS

Our study included 427 patients. Majority were female (n = 313, 73.3%) and underwent sleeve gastrectomy (n = 261, 61.1%). Average age was 45.6 years, and average follow-up was 6.3 years. Greater preoperative weight loss was associated with decreased length of stay (1.8 vs 1.3 days) in patients who underwent sleeve gastrectomy. Multivariable regression analysis revealed that preoperative weight loss was not associated with postoperative weight loss.

CONCLUSIONS

Preoperative weight loss is not predictive of postoperative weight loss success after bariatric surgery. Greater preoperative weight loss was associated with a mild decreased in length of stay but was not associated with a reduction in operative time, overall complication rates, ICU admissions, or intraoperative complications. The inconclusive literature and our findings do not support the medical necessity of weight loss prior to bariatric surgery for the purpose of reducing surgical complications or predicting successful postoperative weight loss success.

Long-Term Weight Outcomes after Bariatric Surgery: A Single Center Saudi Arabian Cohort Experience

BACKGROUND

Obesity is considered a global chronic disease requiring weight management through lifestyle modification, pharmacotherapy, or weight loss surgery. The dramatic increase in patients with severe obesity in Saudi Arabia is paralleled with those undergoing bariatric surgery. Although known to be beneficial in the short term, the long-term impacts of surgery within this group and the sustainability of weight loss after surgery remains unclear.

OBJECTIVES

We aimed to assess the long-term weight outcomes after bariatric surgery.

SETTING

The study was conducted at King Khalid University Hospital (KKUH), King Saud University Medical City (KSUMC) in Riyadh, Saudi Arabia.

METHODS

An observational prospective cohort study on adult patients with severe obesity undergoing bariatric surgery (sleeve gastrectomy (SG) or Roux-en Y gastric bypass (RYGB)) during the period between 2009 and 2015 was conducted. Weight loss patterns were evaluated pre- and post-surgery through clinical and anthropometric assessments. Absolute weight loss was determined, and outcome variables: percent excess weight loss (%EWL), percent total weight loss (%TWL), and percent weight regain (%WR), were calculated. Statistical analysis using univariate and multivariate general linear modelling was carried out.

RESULTS

A total of 91 (46 males and 45 females) patients were included in the study, with the majority belonging to the SG group. Significant weight reductions were observed at 1 and 3 years of follow-up (p < 0.001) from baseline. The %EWL and %TWL were at their maximum at 3 years (72.4% and 75.8%) and were comparable between the SG and RYGB. Decrements in %EWL and %TWL and increases in %WR were seen from 3 years onwards from bariatric surgery until the study period ended. The yearly follow-up attrition rate was 20.8% at 1 year post-surgery, 26.4% at year 2, 31.8% at year 3, 47.3% at year 4, 62.6% at year 5, and 79.1% at end of study period (at year 6).

CONCLUSION

The major challenge to the successful outcome of bariatric surgery is in maintaining weight loss in the long-term and minimizing weight regain. Factors such as the type of surgery and gender need to be considered before and after surgery, with an emphasis on the need for long-term follow-up to enssure the optimal benefits from this intervention.

Metabolic profiles, energy expenditures, and body compositions of the weight regain versus sustained weight loss patients who underwent Roux-en-Y gastric bypass

BACKGROUND

Weight regain (WR) has been an emerging problem after Roux-en Y gastric bypass (RYGB) and little is known about the mechanisms of WR after RYGB.

OBJECTIVE

To evaluate the mechanisms of WR after RYGB through the postprandial gut hormones response, particularly glucagon-like peptide-1 (GLP-1), which regulates appetite control, energy expenditure, body composition, physical activities, dietary intake, and psychological factors.

SETTING

Duke University Medical Center, Durham, North Carolina.

METHODS

A cross sectional study of 34 patients who underwent RYGB at least 2 years and achieved ≥50% of excess weight loss at 1year was conducted. The subjects were categorized into WR group or sustained weight loss group, based upon whether their WR was ≥15% of postoperative lowest weight.

RESULTS

The WR group had less augmented postprandial GLP-1 response but exaggerated hyperinsulinemia. Postprandial peptide YY, ghrelin, and glucose were not different between group. Patients who regained weight required less weight-adjusted energy expenditure and had more percentage body fat and less percentage lean mass. The caloric intake and diet composition were comparable between groups; however, the WR group had higher depression scores, binge eating scales, and hunger rating and spent significantly less time on vigorous exercise.

CONCLUSIONS

The mechanisms of WR in patients who were initially successful after RYGB are complex and involved not only the role of postprandial gut hormone response but are also related to energy expenditure adaptation and body composition changes. Moreover, food preference and physical activity may play roles in weight control after bariatric surgery. Further prospective controlled trial is needed to explore the mechanisms of WR.

Pharmacotherapeutic options for weight regain after bariatric surgery

PURPOSE OF REVIEW

We sought to critically evaluate the recent literature published over the past 3 years on the topic of weight regain after bariatric surgery in children, adolescents, and adults, with an emphasis on clinically- relevant information for pharmacologic treatment of weight regain after metabolic and bariatric surgery.

FINDINGS

There are multiple pharmacotherapeutic agents available to treat obesity in children, adolescents, and adults; these agents have varying efficacy and indications for use and have been studied in a variety of clinical and research scenarios. We present an overview of these findings.

SUMMARY

This review represents a comprehensive compilation of the recently published data on efficacy of anti-obesity pharmacotherapy in the treatment of weight regain after bariatric surgery for children, adolescents, and adults.

Use of Weight Loss Medications in Patients after Bariatric Surgery

PURPOSE OF REVIEW

Weight regain after bariatric surgery is unfortunately a common occurrence. In this article, we have reviewed the data addressing this clinical problem focusing on pharmacological management of weight regain.

RECENT FINDINGS

Data from several small, non-randomized, retrospective, and prospective studies provide evidence that a number of pharmacological options, both FDA approved and off-label, are effective in mitigating and managing weight regain after bariatric surgery. There is a suggestion that the optimal time to initiate weight loss medications may be at the time of weight plateau, rather than after weight regain. Adjuvant pharmacotherapy can help treat weight regain after bariatric surgery. Future studies should investigate the optimal timing for starting weight loss medications, as well as the best medication or combinations of medicines, for managing postoperative weight regain in different patient groups, including those who have undergone different types of bariatric surgeries.

Weight Regain and Insufficient Weight Loss After Bariatric Surgery: Definitions, Prevalence, Mechanisms, Predictors, Prevention and Management Strategies, and Knowledge Gaps-a Scoping Review

Some patients experience weight regain (WR) or insufficient weight loss (IWL) after bariatric surgery (BS). We undertook a scoping review of WR and IWL after BS. We searched electronic databases for studies addressing the definitions, prevalence, mechanisms, clinical significance, preoperative predictors, and preventive and treatment approaches including behavioral, pharmacological, and surgical management strategies of WR and IWL. Many definitions exist for WR, less so for IWL, resulting in inconsistencies in the reported prevalence of these two conditions. Mechanisms and preoperative predictors contributing to WR are complex and multifactorial. A range of the current knowledge gaps are identified and questions that need to be addressed are outlined. Therefore, there is an urgent need to address these knowledge gaps for a better evidence base that would guide patient counseling, selection, and lead to improved outcomes.

Decreased Long-Term Respiratory Infection Risk After Bariatric Surgery: a Comprehensive National Cohort Study

PURPOSE

This study aims to determine whether bariatric surgery (BS) decreases the risk of respiratory tract infections (RTIs) in obese patients.

MATERIALS AND METHODS

This retrospective, population-based, matched cohort study utilized data from the Taiwan National Health Insurance Research Database. All patients 18 to 55 years of age with obesity diagnosed between 2005 and 2010 were enrolled. Patients were separated into two groups based on whether they underwent BS. Two groups were selected using 1:1 propensity score matching according to age, sex, and comorbidities. The general population was also enrolled for comparison. The primary endpoint was the incidence of RTIs, including pneumonia, influenza, and bronchitis. All patients were followed up until the end of 2013, the primary endpoint, or death.

RESULTS

Compared to the non-surgery group, the BS group was at significantly lower risk for RTIs (aHR 0.432, 95% CI 0.340-0.549, p < 0.001) with shorter length of hospital stay (LOH) and lower cost. Regardless of the RTI-related mortality, pneumonia, influenza, and bronchitis rates, BS did have significant protective effects on the non-surgery group. Compared to the general population, the BS group was at higher risk for RTIs (aHR 3.601, 95% CI 2.742-4.728, p < 0.001) with similar LOH and lower cost.

CONCLUSION

Patients with obesity who underwent BS were at significantly lower risk for RTIs than obese patients who did not undergo BS but were at higher risk for RTIs than the general population. BS may result in a long-term reduction of the RTI risk.

The Mitigating Effect of Phentermine and Topiramate on Weight Regain After Roux-en-Y Gastric Bypass Surgery

OBJECTIVE

Weight regain (WR) after Roux-en-Y gastric bypass surgery (RYGB) starts to occur 2 years after surgery, ultimately affecting at least 25% of patients. A limited number of studies have evaluated the impact of antiobesity medications (AOMs) on this phenomenon.

METHODS

This study reviewed the electronic medical records of 1,196 patients who underwent RYGB between 2004 and 2015. WR was evaluated by comparing each patient's weight during subsequent postoperative office visits to nadir weight (lowest weight after RYGB, n = 760), taking into consideration the interval during which WR occurred. Patients who were prescribed AOMs and came to follow-up visits were classified as adherent users, whereas those who missed their follow-up visits were considered nonadherent. This study used a linear mixed model, Cox regression, and generalized equation estimator to determine the impact of AOMs on WR trajectory, hazard ratio for time to event, and odds ratio for repeated event occurrence, respectively.

RESULTS

Despite the lack of a unified protocol for using AOMs, the three statistical models converged to show that phentermine and topiramate, used individually or in combination, can significantly reduce WR after RYGB.

CONCLUSIONS

Phentermine and topiramate are effective in mitigating WR after RYGB. Further studies are needed to help ascertain optimal use of AOMs after bariatric surgery.

Proceedings of the 2017 ASPEN Research Workshop-Gastric Bypass: Role of the Gut

The goal of the National Institutes of Health-funded American Society for Parenteral and Enteral Nutrition 2017 research workshop (RW) "Gastric Bypass: Role of the Gut" was to focus on the exciting research evaluating gut-derived signals in modulating outcomes after bariatric surgery. Although gastric bypass surgery has undoubted positive effects, the mechanistic basis of improved outcomes cannot be solely explained by caloric restriction. Emerging data suggest that bile acid metabolic pathways, luminal contents, energy balance, gut mucosal integrity, as well as the gut microbiota are significantly modulated after bariatric surgery and may be responsible for the variable outcomes, each of which was rigorously evaluated. The RW served as a timely and novel academic meeting that brought together clinicians and researchers across the scientific spectrum, fostering a unique venue for interdisciplinary collaboration among investigators. It promoted engaging discussion and evolution of new research hypotheses and ideas, driving the development of novel ameliorative, therapeutic, and nonsurgical interventions targeting obesity and its comorbidities. Importantly, a critical evaluation of the current knowledge regarding gut-modulated signaling after bariatric surgery, potential pitfalls, and lacunae were thoroughly addressed.

The Role of Bariatric Surgery on Diabetes and Diabetic Care Compliance

PURPOSE OF REVIEW

Bariatric surgery is a durable and long-term solution to treat both obesity and its associated comorbidities, specifically type 2 diabetes mellitus (T2DM). Many studies have demonstrated the benefits of bariatric surgery on T2DM, but weight recidivism along with recurrence of comorbidities can be seen following these procedures. Patient compliance post-bariatric surgery is linked to weight loss outcomes and comorbidity improvement/resolution. The role of compliance with respect to T2DM medication in bariatric patients specifically has not recently been examined. This article seeks to review the role of bariatric surgery on short- and long-term resolution of T2DM, recurrence, and compliance with T2DM medication following bariatric surgery.

RECENT FINDINGS

Seven randomized control trials have examined metabolic surgery versus medical therapy in glycemic control in patients meeting criteria for severe obesity. Six out of seven studies demonstrate a significant advantage in the surgical arms with regards to glycemic control, as well as secondary endpoints such as weight loss, serum lipid levels, blood pressure, renal function, and other parameters. While patient compliance with lifestyle modifications post-bariatric surgery is linked to weight loss outcomes, there are no studies to date that directly evaluate the role of lifestyle modifications and T2DM medication adherence in the management of T2DM post-bariatric surgery. Bariatric surgery is an effective treatment option to achieve long-term weight loss and resolution of obesity-related medical comorbidities, specifically T2DM. Patient compliance to lifestyle modifications post-bariatric surgery is linked to weight loss outcomes and comorbidity resolution. The role of diabetic care compliance in bariatric patient outcomes, however, is poorly understood. Further studies are needed to elucidate the predictors and associated risk factors for non-compliance in this patient population.

Long-term pharmacotherapy of obesity in patients that have undergone bariatric surgery: pharmacological prevention and management of body weight regain

INTRODUCTION

The obesity epidemic continues to grow. Bariatric surgery is part of the arsenal to treat the disease. Surgery results in an effective option for patients with severe obesity but also when obesity is associated with significant comorbidities. Weight regain is frequent after bariatric surgery. Consequently, the addition of anti-obesity drugs to prevent and manage weight regain are commonly recommended even when the quality of the evidence supporting this recommendation is relatively weak. cfsda65

AREAS COVERED

The aim of this review is to summarize the available evidence concerning long-term pharmacotherapy of obesity in patients that have undergone bariatric surgery with a focus on pharmacological prevention and management of weight regain. The etiology and epidemiology of weight regain are summarized, as well as the available information about the benefits and risks of long-term pharmacotherapy in the prevention and management of recidivism.

EXPERT OPINION

The available information, mainly obtained from observational studies and small trials, is encouraging but calls for a prudent approach in the selection of appropriate agents for each individual patient and a careful follow-up to detect adverse reactions or drug interactions. Results from well-designed trials are upcoming. In the meantime, a cautious, individualized approach is advisable.

Endoscopic management of weight regain following Roux-en-Y gastric bypass

INTRODUCTION

With the cumulative increase in the number of patients undergoing bariatric surgery, postoperative weight regain has become a considerable challenge. Mechanisms for weight regain are not fully understood and the process is likely multifactorial in many cases. Endoluminal revisions that reduce gastric pouch size and diameter of the gastrojejunal anastomosis may offer an effective and less invasive management strategy for this population.

AREAS COVERED

We critically review data from case series, retrospective and prospective studies, and meta-analyses pertaining to weight regain after gastric bypass. A variety of endoscopic revision approaches are reviewed, including technique details, procedural safety and efficacy, and post-procedure care.

EXPERT COMMENTARY

Given the proliferation of endoluminal therapies with evidence showing safety and efficacy in the treatment of weight regain, it is likely that endoscopic revision will be the gold standard to treat weight regain in patients with gastric bypass.

Weight Recidivism After Roux-en-Y Gastric Bypass Surgery: An 11-Year Experience in a Multiethnic Medical Center

OBJECTIVE

Weight recidivism following Roux-en-Y gastric bypass (RYGB) is common and is associated with recurrence of comorbidities. Studies with long-term follow-up of recidivism quantified by weight regain (WR) are lacking. A retrospective review of all RYGB at our center from 2004 to 2015 was performed to examine the effects of race and type 2 diabetes on WR following RYGB.

METHODS

Multivariable linear mixed models were used for the effects of time and race on weight, WR relative to nadir weight (WR/nadir), and WR relative to maximal weight loss, and Cox regressions were used for low, moderate, and high WR/nadir.

RESULTS

A total of 1,395 participants were identified. The sample was limited to African American (AA), Caucasian American (CA), and Hispanic American (HA) participants. The effects of time (P < 0.0001), race (P < 0.0001), and race × time interaction (P = 0.0008) on weight trajectory were significant. AA had significantly more WR than CA (P < 0.01). AA and HA had a higher hazard ratio for having low, moderate, and rapid WR/nadir.

CONCLUSIONS

Racial disparities after RYGB include WR and particularly affect AA. Understanding the etiologic factors that contribute to these disparities is important to optimize the long-term clinical outcomes of bariatric surgery.

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.

Future Pharmacotherapy for Obesity: New Anti-obesity Drugs on the Horizon

PURPOSE OF REVIEW

Obesity is a global health crisis with detrimental effects on all organ systems leading to worsening disease state and rising costs of care. Persons with obesity failing lifestyle therapies need to be escalated to appropriate pharmacological treatment modalities, medical devices, and/or bariatric surgery if criteria are met and more aggressive intervention is needed. The progression of severe obesity in the patient population coupled with related co-morbidities necessitates the development of novel therapies for the treatment of obesity. This development is preceded by increased understanding of the underpinnings of energy regulation and neurohormonal pathways involved in energy homeostasis.

RECENT FINDINGS

Though there are approved anti-obesity drugs available in the USA, newer drugs are now in the pipeline for development given the urgent need. This review focuses on anti-obesity drugs in the pipeline including centrally acting agents (setmelanotide, neuropeptide Y antagonist [velneperit], zonisamide-bupropion [Empatic], cannabinoid type-1 receptor blockers), gut hormones and incretin targets (new glucagon-like-peptide-1 [GLP-1] analogues [semaglutide and oral equivalents], amylin mimetics [davalintide, dual amylin and calcitonin receptor agonists], dual action GLP-1/glucagon receptor agonists [oxyntomodulin], triple agonists [tri-agonist 1706], peptide YY, leptin analogues [combination pramlintide-metreleptin]), and other novel targets (methionine aminopeptidase 2 inhibitor [beloranib], lipase inhibitor [cetilistat], triple monoamine reuptake inhibitor [tesofensine], fibroblast growth factor 21), including anti-obesity vaccines (ghrelin, somatostatin, adenovirus36). With these new drugs in development, anti-obesity therapeutics have potential to vastly expand allowing better treatment options and personalized approach to obesity care.

Satiety and gastrointestinal hormones during a Mixed Meal Tolerance Test after gastric bypass surgery: association with plasma amino acid concentrations

BACKGROUND

Circulating amino acids have been associated with both appetite and the secretion of anorexigenic hormones in healthy and obese populations. This effect has not been investigated in subjects having undergone Roux-en-Y gastric bypass surgery (RYGB).

OBJECTIVE

To investigate the association between postprandial plasma concentrations of amino acids and the anorexigenic hormones glucagon-like peptide-1 (GLP-1) and peptide tyrosine tyrosine (PYY), the orexigenic hormone ghrelin, and satiety and hunger in post-RYGB subjects.

SETTING

A Dutch surgical department.

METHODS

Participants after primary RYGB were studied during a Mixed Meal Tolerance Test (MMTT). Satiety and hunger were assessed every 30 minutes on visual analogue scales. Blood samples were collected at baseline, every 10 minutes during the first half hour and every 30 minutes until 210 minutes after the start. The samples were assessed for 24 amino acids and 3 gastrointestinal hormones. Incremental areas under the curve (iAUCs) were calculated. Exploratory analyses were performed in which subjects were divided into high and low responders depending on the median iAUC.

RESULTS

42 subjects, aged 48 ± 11 (mean ± SD) years, 31 to 76 months post-RYGB and with total weight loss of 30 ± 9% completed the MMTT. Subjects with high satiety scores had more than a 25% higher net iAUC of PYY and GLP-1 and at least a 10% higher net iAUC of 10 amino acids compared to subjects with low scores (P < 0.05). The net iAUC of five of these amino acids (i.e. arginine, asparagine, histidine, serine and threonine) was more than 10% higher in subjects with high responses on GLP-1 and/or PYY (P < 0.05).

CONCLUSIONS

Certain postprandial amino acids were associated with satiety and anorexigenic hormones and could therefore play a role in appetite regulation after RYGB; either by a direct effect on satiety, indirectly through gastrointestinal hormones, or both.

Long term maintenance of glucose and lipid concentrations after Roux-en-Y gastric bypass

OBJECTIVE

Roux-en-Y gastric bypass (RYGB) reduces body weight and the comorbidities associated with obesity. The aim of this study was to evaluate whether glucose and lipid profiles were maintained during a 5-year follow-up period after RYGB.

SUBJECTS AND METHODS

Anthropometric and laboratory data from 323 patients who had undergone this operation were analyzed. Differences in laboratory variables between the baseline and 12, 24, 36, 48 and 60 months postoperatively (PO) were assessed using a one-way ANOVA test to compare the three groups. Delta significance using one-way ANOVA was performed to assess anthropometric variable in the postoperative period (p < 0.05).

RESULTS

77 patients (24%) were included in Group 1 (G1), 101 (32%) in Group 2 (G2), and 141 (44%) in Group 3 (G3). The majority of patients, 71.7% in G1, 82.8% in G2, and 70% in G3, showed high triglycerides (TG) before surgery. A decrease in weight loss was observed in all groups followed by an increase in body weight in G2 and G3 at 36, 48 and 60 months. Laboratory results for G1, G2 and G3 showed no significant differences between groups at baseline and during the post-operative period.

CONCLUSION

Our results suggest that weight regain after RYGB has no significant impact on the long-term evolution of the lipid profile and glycemia.

Baseline Anthropometric and Metabolic Parameters Correlate with Weight Loss in Women 1-Year After Laparoscopic Roux-En-Y Gastric Bypass

BACKGROUND

In this study, we explored in a prospective cohort of morbidly obese women undergoing laparoscopic Roux-en-Y gastric bypass (LRYGP) correlations between baseline anthropometrics, metabolic parameters, resting energy expenditure (REE), body composition, and 1-year % excess body mass index loss (%EBMIL). We also investigated risk factors for insufficient %EBMIL.

METHODS

One hundred three consecutive women were prospectively evaluated at baseline (age 40.6 ± 11.2, weight 113.9 kg ± 15.3, BMI 43.3 ± 4.9 kg/m²) and 1 year after LRYGP. Weight, excess weight, brachial circumference, waist circumference, fat mass (FM) and fat-free mass (FFM) (measured with bioelectrical impedance analysis), REE, inflammation, insulin resistance, and lipid disturbances were determined before and 1 year after LRYGP.

RESULTS

At 1 year, mean weight loss was 39.8 kg ± 11.7 and mean EBMIL was 15.2 kg/m² ± 4.2. Mean %EBMIL was 86% ± 21% (range 30-146%). Baseline brachial circumference, waist circumference and triceps skinfold thickness decreased significantly at 1 year (P < 0.001). Blood glucose and insulin levels, HDL cholesterol, LDL cholesterol, triglycerides, and CRP also decreased significantly (P < 0.001). The mean loss of initial FFM and FM was 9.1 kg ± 8.2 (15%) and 30.7 kg ± 11.8 (53%), respectively. REE on body weight ratio (REE/BW) increased from 15.3 kcal/kg ± 2.8 to 18.4 kcal/kg ± 2.5 (p < 0.0001) and REE on FFM ratio decreased from 31.2 to 28.7 kcal/day/kg (p < 0.001). Preoperative waist circumference (r = -0.3; P < 0.001), blood glucose level (r = -0.37; P < 0.001), and CRP (r = -0.28; P = 0.004) were negatively correlated with EBMIL% 1 year after surgery. Among baseline body composition parameters, only preoperative FM was negatively correlated with %EBMIL (r = -0.23; p = 0.02). One year after surgery FM change was negatively correlated with EBMIL% (r = -0.49; P < 0.001) while FFM/BW ratio was positively correlated with %EBMIL (r = 0.71; P < 0.001). Increase in REE/BW at 1 year was positively correlated with %EBMIL (r = 0.47; p < 0.001). On multivariate analysis, baseline blood glucose level (OR = 1.77; CI 95%: [1.3-2.4]) was the only predictive factor of EBMIL <60% at 1 year.

CONCLUSION

LRYGB has beneficial effects on clinical, biological parameters, and body composition. Increasing the proportion of FFM on total BW and REE/BW is associated with better results in terms of weight loss. Baseline glucose level may be helpful in identifying poor responders to LRYGBP.

TRIAL REGISTRATION

NCT02820285y ( https://clinicaltrials.gov/ct2/show/NCT02820285?term=Characterization+of+Immune+Semaphorin+in+Non-Alcoholic+Fatty+Liver+Disease+and+NASH&rank=1 ).

Current concepts in management of weight regain following bariatric surgery

INTRODUCTION

Although bariatric surgery is the most effective and durable treatment for obesity, weight regain is common.

AREAS COVERED

In this article, we have critically reviewed data from retrospective and prospective studies pertaining to prevalence and predictors of weight regain following bariatric surgery, as well as the utility of behavioral and pharmacotherapeutic interventions to address post-surgical weight regain.

EXPERT COMMENTARY

The initial step in management of post-surgical weight regain is a comprehensive evaluation of the patient including a thorough assessment of contributing factors. While lifestyle interventions including diet, exercise and behavior modification are fundamental, they have limited efficacy which can be enhanced by pharmacotherapy. The optimal time to commence pharmacotherapy may be at weight plateau to maximize weight loss outcomes after bariatric surgery. Further prospective studies are needed to determine the best combination of behavioral and pharmacological therapies, and also the timing of pharmacotherapeutic intervention.

Regulation of Energy Homeostasis After Gastric Bypass Surgery

The obesity epidemic continues to escalate each year in the United States more than anywhere else in the world. The existing pharmaceutical and other nonsurgical treatments for morbid obesity produce suboptimal physiologic outcomes compared with those of Roux-en-Y gastric bypass (RYGB) surgery. RYGB has been the gold standard of bariatric surgery because the beneficial long-term outcomes, which include sustainable weight loss and type 2 diabetes mellitus (T2DM) resolution, are far superior to those obtained with other bariatric surgeries. However, the current understanding of RYGB's mechanisms of actions remains limited and incomplete. There is an urgent need to understand these mechanisms as gaining this knowledge may lead to the development of innovative and less invasive procedures and/or medical devices, which can mirror the favorable outcomes of RYGB surgery. In this review, we highlight current observations of the metabolic and physiologic events following RYGB, with a particular focus on the role of the anatomical reconfiguration of the gastrointestinal tract after RYGB.

Does the ileal brake mechanism contribute to sustained weight loss after bariatric surgery?

Bariatric surgery is currently the most effective strategy for treating morbid obesity. Weight regain following significant weight loss, however, remains a problem, with the outcome proportional to the period of follow-up. This review revisits a well-established physiological neurohormonally-mediated feedback loop, the so called ileal brake mechanism, with a special emphasis on the gut hormone peptide tyrosine tyrosine. The manuscript not only highlights the potential role of the ileal brake mechanism in weight loss and weight maintenance thereafter following obesity surgery, it also provides a compelling argument for using this appetite suppressing feedback loop to enable sustained long-term weight loss in patients undergoing surgery for morbid obesity.

Short- and Long-Term Effects of Weight Loss on the Complement Component C3 After Laparoscopic Gastric Bypass in Obese Patients

BACKGROUND

The C3 complement component (C3c) is increasingly recognized as a cardiometabolic risk factor, but how it is affected after weight loss through gastric bypass is a question yet to be answered.

METHODS

A total of 66 obese patients underwent laparoscopic gastric bypass. Anthropometric parameters, total cholesterol (TC), triglycerides, high-density lipoprotein cholesterol (HDLc), low-density lipoprotein cholesterol (LDLc), glucose, insulin, HOMA-IR, liver enzymes, high-sensitivity C-reactive protein (hsCRP), and C3c levels were evaluated at baseline and at 1 and 5 years post-surgery.

RESULTS

All anthropometric and biochemical parameters improved significantly after surgery, although a deterioration was detected with respect to the percentage of excess of weight loss, insulin, TC, LDLc, and lactate dehydrogenase 5 years post-surgery. Despite this, a remission rate of 84 % was observed in the presence of metabolic syndrome after 5 years follow-up. hsCRP and C3c were reduced significantly after surgery and maintained throughout the experimental period. In addition, C3c was correlated with BMI and insulin at all time points. The multivariate regression model, in which C3c was a dependent variable, revealed that aspartate aminotransferase and BMI were independent variables at baseline, alkaline phosphatase and insulin were independent at 1 year post-surgery, and insulin, BMI, and TC were independent at 5 years post-surgery.

CONCLUSIONS

C3c may be a marker of the chronic inflammatory process underlying insulin resistance. Its association with BMI and liver enzymes supports a major role in metabolic activity, although future research is needed to clarify the nature of the molecular mechanisms involved and the physiological significance of these findings.

Predictive factors of weight regain following laparoscopic Roux-en-Y gastric bypass

BACKGROUND

Strategies to address weight recidivism following Roux-en-Y gastric bypass (RYGB) could be developed if patients at risk were identified in advance. This study aimed to determine factors that predict weight regain.

METHODS

Retrospective review was performed of patients who underwent laparoscopic RYGB at a single institution over 10 years. Group-based modeling was used to estimate trajectories of weight regain after nadir and stratify patients based on percent weight change (%WC).

RESULTS

Three trajectories were identified from 586 patients: 121 had ongoing weight loss, 343 were weight stable, and 122 regained weight. Male sex (p = 0.020) and white race (p < 0.001) were associated with stable weight or weight regain. Being from a neighborhood of socioeconomic advantage (p = 0.035) was associated with weight regain. Patients with weight regain experienced improved percent weight loss (%WL) at nadir (p < 0.001) and ΔBMI (p = 0.002), yet they had higher weight and BMI and lower %WL and ΔBMI than the other two groups during long-term follow-up. On multivariate analyses, those who regained weight were more likely from socioeconomically advantaged neighborhoods (OR 1.82, CI 1.18-2.79).

CONCLUSIONS

Several patient-related characteristics predicted an increased likelihood of weight regain. Further studies are needed to elucidate how these factors contribute to weight recidivism following bariatric surgery.

Central and peripheral control of food intake

The maintenance of the body weight at a stable level is a major determinant in keeping the higher animals and mammals survive. Th e body weight depends on the balance between the energy intake and energy expenditure. Increased food intake over the energy expenditure of prolonged time period results in an obesity. Th e obesity has become an important worldwide health problem, even at low levels. The obesity has an evil effect on the health and is associated with a shorter life expectancy. A complex of central and peripheral physiological signals is involved in the control of the food intake. Centrally, the food intake is controlled by the hypothalamus, the brainstem, and endocannabinoids and peripherally by the satiety and adiposity signals. Comprehension of the signals that control food intake and energy balance may open a new therapeutic approaches directed against the obesity and its associated complications, as is the insulin resistance and others. In conclusion, the present review summarizes the current knowledge about the complex system of the peripheral and central regulatory mechanisms of food intake and their potential therapeutic implications in the treatment of obesity.

The Role of PYY in Pancreatic Islet Physiology and Surgical Control of Diabetes

Bariatric surgery in obese individuals leads to rapid and lasting remission of type 2 diabetes (T2D). This phenomenon occurs independently of weight loss possibly via a combination of factors. The incretin hormone GLP-1 has so far been recognised as a critical factor. However, recent data have indicated that elevation in another gut hormone, peptide tyrosine tyrosine (PYY), may drive the beneficial effects of surgery. Here we discuss recent findings on PYY-mediated control of glucose homeostasis and its role in diabetes, in the context of what is known for GLP-1. Identification of factors that increase the expression of PYY following bariatric surgery and elucidation of its role in diabetes reversal may have clinical relevance as a nonsurgical therapy for T2D.

Does Bariatric Surgery Improve Obesity Associated Comorbid Conditions

Obesity is a constantly growing health problem which reduces quality of life and life expectancy. Bariatric surgery for obesity is taken into account when all other conservative treatment modalities have failed. Comparison of the multidisciplinary programs with bariatric surgery regarding to weight loss showed that substantial and durable weight reduction have been achieved only with bariatric surgical treatments. However, the benefits of weight loss following bariatric procedures are still debated regarding the pro-inflammatory and metabolic profile of obesity.

Weight Loss Outcomes in Laparoscopic Vertical Sleeve Gastrectomy (LVSG) Versus Laparoscopic Roux-en-Y Gastric Bypass (LRYGB) Procedures: A Meta-Analysis and Systematic Review of Randomized Controlled Trials

PURPOSE

Laparoscopic Roux-en-Y gastric bypass (LRYGB) and laparoscopic vertical sleeve gastrectomy (LVSG) have been proposed as cost-effective strategies to manage morbid obesity. The aim of this meta-analysis was to compare the postoperative weight loss outcomes reported in randomized control trials (RCTs) for LVSG versus LRYGB procedures.

MATERIAL AND METHODS

RCTs comparing the weight loss outcomes following LVSG and LRYGB in adult population between January 2000 and November 2015 were selected from PubMed, Medline, Embase, Science Citation Index, Current Contents, and the Cochrane database. The review was prepared in accordance with Preferred Reporting of Systematic Reviews and Meta-Analyses (PRISMA).

RESULTS

Nine unique RCTs described over 10 publications involving a total of 865 patients (LVSG, n=437; LRYGB, n=428) were analyzed. Postoperative follow-up ranged from 3 months to 5 years. Twelve-month excess weight loss (EWL) for LVSG ranged from 69.7% to 83%, and for LRYGB, ranged from 60.5% to 86.4%. A number of studies reported slow weight gain between the second and third years of postoperative follow-up ranging from 1.4% to 4.2%EWL. This trend was seen to continue to 5 years postoperatively (8% to 10%EWL) for both procedures.

CONCLUSIONS

In conclusion, LRYGB and LVSG are comparable with regards to the weight loss outcomes in the short term, with LRYGB achieving slightly greater weight loss. Slow weight recidivism is observed after the first postoperative year following both procedures. Long-term reporting of outcomes obtained from well-designed studies using intention-to-treat analyses are identified as a major gap in the literature at present.

Weight Regain After Gastric Bypass: Influence of Gut Hormones

BACKGROUND

The Roux-en-Y gastric bypass (RYGB) is the gold standard bariatric operation. However, a major concern in late follow-up is the substantial weight regain. Understanding the role of gastrointestinal hormone secretion in this situation is relevant.

METHODS

The aim of the present study was to evaluate the influence of gastrointestinal hormones comparing postprandial secretion of ghrelin, glucose-dependent insulinotropic polypeptide (GIP), glucagon-like peptide 1 (GLP-1), and leptin between patients with weight regain and those with favorable weight control. Twenty-four patients with follow-up from 27 to 59 months were divided into two groups according to sustained weight loss: group A (14 patients) had sustained weight losses, and group B (10 patients) had significant weight regain. Basal serum levels of ghrelin, GIP, GLP-1, and leptin after fasting and 30, 60, 90, and 120 min after a standard meal were measured.

RESULTS

There was no difference in the ghrelin secretion. There was a difference in the GIP secretion, with a higher percentage increase in 30 min in group A (330% × 192.2%; p = 0.01). There were also differences in the GLP-1 secretion, with higher increases in absolute (p = 0.03) and percentage values after 30 min in group A (124% × 46.5%; p = 0.01). There was also a difference between baseline leptin values, with higher levels in group B (p = 0.02).

CONCLUSIONS

The secretion of gut hormones in patients with weight regain after RYGB is different from that in patients with satisfactory weight outcome. After meal stimulation, reduced levels of GIP and GLP-1 may indicate the influence of gut hormones in the process of weight regain.