Impact of Laparoscopic Roux-en-Y Gastric Bypass on Metabolic Syndrome, Inflammation, and Insulin Resistance in Super Versus Morbidly Obese Women

Bariatric Surgery and Remission of Metabolic Syndrome: A Meta-analysis of Randomised Controlled Trials and Prospective Studies

BACKGROUND

Studies have discussed the efficacy of bariatric surgery (BS) in remission of individual components of metabolic syndrome (MS). We aimed to analyse the prevalence of MS following BS.

METHODS

On October 5, 2023, we conducted a literature search on PubMed, Scopus, Web of Science, and Cochrane. RevManv5.4 was used for the analysis.

RESULTS

MS patients who underwent BS had lower odds of MS within the first year post-BS (OR 0.14, 95%CI 0.12-0.17); patients who had a preoperative BMI < 50 showed a higher reduction in MS post-BS compared with patients who suffered from super obesity (OR 0.12 versus OR 0.17). Older patients (age > 42) had lower odds of MS post-BS compared with younger patients (OR 0.05 versus OR 0.17). There was not a difference in MS prevalence between 1 and 2 years postoperatively (OR 1.07, 95%CI 0.72-1.58). Asians reported the highest reduction in MS post-BS (OR 0.08). MS patients who received medical treatment had three times the odds of having MS compared with patients who underwent BS. Patients who had BS reported a decline in their anti-hypertensives and oral anti-diabetic drugs (OR 0.26, 95%CI 0.15-0.46, OR 0.11, 95%CI 0.07-0.16, respectively). There was not a significant difference in MS prevalence between patients who underwent RYGB and those who had SG (OR 2.16, 95%CI 0.74-6.26).

CONCLUSIONS

BS is superior to medical treatment in the remission of MS. Age, preoperative BMI, and country of origin affect the rates of MS remission. BS results in a sustainable resolution of MS across 1, 2, and 5 years post-surgery. A tailored approach is warranted to achieve the best outcomes.

Bariatric surgery in the prevention of obesity-associated cancers: mechanistic implications

Obesity is associated with an increased risk of at least 13 different cancers, as well as worse cancer outcomes and increased cancer mortality. As rates continue to rise both in the United States and worldwide, obesity is poised to become the leading lifestyle-related risk factor for cancer. Currently, the most effective treatment for patients with severe obesity is bariatric surgery. Multiple cohort studies have demonstrated a consistent >30% decreased risk of cancer incidence in women, but not men, following bariatric surgery. However, the physiologic mechanisms driving obesity-associated cancer and the cancer-protective effect of bariatric surgery are not clearly defined. In this review, we highlight emerging concepts in the mechanistic understanding of obesity-associated cancer. Evidence from both human studies and preclinical animal models suggest that obesity drives carcinogenesis through dysregulation of systemic metabolism, immune dysfunction, and an altered gut microbiome. Additionally, we present related findings to suggest that bariatric surgery may disrupt and even reverse many of these mechanisms. Finally, we discuss the use of preclinical bariatric surgery animal models in the study of cancer biology. The prevention of cancer is emerging as an important indication for bariatric surgery. Elucidating the mechanisms through which bariatric surgery limits carcinogenesis is critical to developing a variety of interventions that intercept obesity-driven cancer.

How Does Fat Mass Change in the First Year After Bariatric Surgery? A Systemic Review and Meta-Analysis

This systematic review and meta-analysis investigated the time-course effect of different type of bariatric surgeries (BS) up to 1 year post-surgery on fat mass (FM) and body fat percentage (BFP) in patients with morbid obesity. We searched PubMed, Scopus, EMBASE, ISI web of science, and Cochrane databases from October 2002 until May 2020 with no restriction in the English language, to find studies examining the effect of BS on FM (kg) and BFP (%) in morbid obese patients. Meta-analysis of 103 studies carried out on data of 18,166 and 14,575 morbid obese patients following BS, showed that BS was associated with a substantial decrease in FM and BFP, respectively, in 1 month (- 8.17 kg [95% CI - 9.07, - 7.27] and - 1.51% [95% CI - 2.56, - 0.46]), 3 months (- 15.75 [95% CI - 17.49, - 14.0] and - 4.90 [95% CI - 5.97, - 3.83]), 6 months (- 22.51 [95% CI - 23.93, - 21.09] and - 8.56% [95% CI - 9.63, - 7.49]), and 12 months (- 29.69 [95% CI - 31.3, - 28.09] and - 13.49% [95% CI - 14.52, - 12.40]) after the surgery. In conclusion, BS was associated with sustained declines in FM and BFP, from 1 to 12 months, with no indication of plateau phase post-surgery post-operatively. The present study emphasizes that post-bariatric care should have more focus on FM loss during 1-year post-surgery to identify the patients at risk for fat loss plateau.

Temporospatial shifts in the human gut microbiome and metabolome after gastric bypass surgery

Although the etiology of obesity is not well-understood, genetic, environmental, and microbiome elements are recognized as contributors to this rising pandemic. It is well documented that Roux-en-Y gastric bypass (RYGB) surgery drastically alters the fecal microbiome, but data are sparse on temporal and spatial microbiome and metabolome changes, especially in human populations. We characterized the structure and function (through metabolites) of the microbial communities in the gut lumen and structure of microbial communities on mucosal surfaces in nine morbidly obese individuals before, 6 months, and 12 months after RYGB surgery. Moreover, using a comprehensive multi-omic approach, we compared this longitudinal cohort to a previously studied cross-sectional cohort (n = 24). In addition to the expected weight reduction and improvement in obesity-related comorbidities after RYGB surgery, we observed that the impact of surgery was much greater on fecal communities in comparison to mucosal ones. The changes in the fecal microbiome were linked to increased concentrations of branched-chain fatty acids and an overall decrease in secondary bile acid concentrations. The microbiome and metabolome data sets for this longitudinal cohort strengthen our understanding of the persistent impact of RYGB on the gut microbiome and its metabolism. Our findings highlight the importance of changes in mucosal and fecal microbiomes after RYGB surgery. The spatial modifications in the microbiome after RYGB surgery corresponded to persistent changes in fecal fermentation and bile acid metabolism, both of which are associated with improved metabolic outcomes.

Adipose Tissue Distribution, Inflammation and Its Metabolic Consequences, Including Diabetes and Cardiovascular Disease

Adipose tissue plays essential roles in maintaining lipid and glucose homeostasis. To date several types of adipose tissue have been identified, namely white, brown, and beige, that reside in various specific anatomical locations throughout the body. The cellular composition, secretome, and location of these adipose depots define their function in health and metabolic disease. In obesity, adipose tissue becomes dysfunctional, promoting a pro-inflammatory, hyperlipidemic and insulin resistant environment that contributes to type 2 diabetes mellitus (T2DM). Concurrently, similar features that result from adipose tissue dysfunction also promote cardiovascular disease (CVD) by mechanisms that can be augmented by T2DM. The mechanisms by which dysfunctional adipose tissue simultaneously promote T2DM and CVD, focusing on adipose tissue depot-specific adipokines, inflammatory profiles, and metabolism, will be the focus of this review. The impact that various T2DM and CVD treatment strategies have on adipose tissue function and body weight also will be discussed.

Study of changes of obesity-related inflammatory cytokines after laparoscopic sleeve gastrectomy

BACKGROUND

Chronic inflammation in adipose tissue may play a substantial role in the pathogenesis of obesity-related metabolic disorders. The present study aims to evaluate the changes in adipocytokines, bile acids, fibroblast growth factor 19 (FGF-19) and pro-inflammatory cytokines 6 months after laparoscopic sleeve gastrectomy (LSG).

METHODS

This prospective study included 75 obese patients with body mass index >35 kg/m2 who underwent LSG. All patients were recruited preoperatively and followed up post-operatively at 6 months, with laboratory assessment of their cytokines including adiponectin, leptin, resistin, bile acid, interleukin (IL)-6, IL-8, tumour necrosis factor-α, monocyte chemotactic protein-1, high-sensitivity C-reactive protein, plasminogen activator inhibitor-1, serum amyloid-A and FGF-19.

RESULTS

There were statistically highly significant changes regarding anthropometric parameters (weight, body mass index and waist-to-hip ratio), blood glucose and lipid profile as well as liver enzymes at 6 months post-sleeve gastrectomy. The present study showed that the levels of serum adiponectin and FGF-19 significantly increased at 6 months of follow-up after surgery (P < 0.001), while the levels of serum leptin, resistin, high-sensitivity C-reactive protein, plasminogen activator inhibitor-1 and serum amyloid-A significantly decreased at 6 months of follow-up after surgery (P < 0.001). There were no significant differences regarding serum bile acid, IL-6, IL-8, tumour necrosis factor-α and monocyte chemotactic protein-1.

CONCLUSION

Weight loss after LSG is associated with significant improvement of the adipokine levels towards anti-diabetic and anti-inflammatory profiles. Future studies should use a larger sample size and longer follow-up periods.

Contribution of Adipose Tissue Inflammation to the Development of Type 2 Diabetes Mellitus

The objective of this comprehensive review is to summarize and discuss the available evidence of how adipose tissue inflammation affects insulin sensitivity and glucose tolerance. Low-grade, chronic adipose tissue inflammation is characterized by infiltration of macrophages and other immune cell populations into adipose tissue, and a shift toward more proinflammatory subtypes of leukocytes. The infiltration of proinflammatory cells in adipose tissue is associated with an increased production of key chemokines such as C-C motif chemokine ligand 2, proinflammatory cytokines including tumor necrosis factor α and interleukins 1β and 6 as well as reduced expression of the key insulin-sensitizing adipokine, adiponectin. In both rodent models and humans, adipose tissue inflammation is consistently associated with excess fat mass and insulin resistance. In humans, associations with insulin resistance are stronger and more consistent for inflammation in visceral as opposed to subcutaneous fat. Further, genetic alterations in mouse models of obesity that reduce adipose tissue inflammation are-almost without exception-associated with improved insulin sensitivity. However, a dissociation between adipose tissue inflammation and insulin resistance can be observed in very few rodent models of obesity as well as in humans following bariatric surgery- or low-calorie-diet-induced weight loss, illustrating that the etiology of insulin resistance is multifactorial. Taken together, adipose tissue inflammation is a key factor in the development of insulin resistance and type 2 diabetes in obesity, along with other factors that likely include inflammation and fat accumulation in other metabolically active tissues. © 2019 American Physiological Society. Compr Physiol 9:1-58, 2019.

Increased Prevalence of Irritable Bowel Syndrome in a Cohort of French Morbidly Obese Patients Candidate for Bariatric Surgery

BACKGROUND

Only a few recent reports have suggested a correlation between obesity and irritable bowel syndrome (IBS). We aimed to determine the prevalence and severity of IBS in a prospective cohort of obese patients undergoing bariatric surgery in Nice Hospital (France).

METHODS

One hundred obese patients were included prospectively before bariatric surgery. A diagnosis of IBS and each subtype was performed according to Rome-III criteria using a Bristol scale for stool consistency. Patients provided information on IBS-related comorbidities, including chronic fatigue, migraine, lower back pain, gastroesophageal reflux disease (GERD), genitourinary problems, and dyspepsia. Patients completed questionnaires to assess the severity of IBS, GERD, psychological factors (anxiety, depression), fatigue, and quality of life.

RESULTS

Thirty patients fulfilled the Rome-III criteria for IBS. There was no difference in age, gender, or BMI between obese patients with or without IBS. Obese patients with IBS reported a significantly higher prevalence of GERD, migraines, lower back pain, genitourinary problems, chronic fatigue, and dyspepsia. Obese patients with IBS had significant higher scores of fatigue, anxiety, depression, and poorer quality of life. Obese patients that had both IBS and GERD had significantly higher IBS severity scores than those without GERD. In a logistic regression model including BMI, anxiety, depression, gender, and GERD score, only anxiety was significantly and independently associated with IBS.

CONCLUSIONS

Thirty percent of obese patients had IBS: its severity was not correlated with BMI. However, anxiety was independently associated with IBS, suggesting that psychological factors are key features of IBS, whatever the presence of obesity.

Impact of Roux-en-Y gastric bypass on lipid and inflammatory profiles

OBJECTIVE

To evaluate the behavior of acute phase proteins and lipid profile in patients undergoing Roux-en-Y gastric bypass.

METHODS

We conducted a prospective study, consisting of three moments: M1 - preoperative (24 hours before surgery); M2 - 30 days after surgery; and M3 - 180 days after surgery. We carried measured height and BMI, as well as determined the concentrations of acute phase proteins (C-reactive protein (CRP), albumin and Alpha-1-acid glycoprotein) and total cholesterol, LDL-c, HDL-c and triacylglycerol.

RESULTS

participants comprised 25 individuals, with a mean age of 39.28 ± 8.07, 72% female. At all times of the study there was statistically significant difference as for weight loss and BMI. We found a significant decrease in CRP concentrations between the moments M1 and M3 (p = 0.041) and between M2 and M3 (p = 0.018). There was decrease in Alpha-1-GA concentrations between M1 and M2 (p = 0.023) and between M1 and M3 (p = 0.028). The albumin values increased, but did not differ between times. Total cholesterol and triacylglycerol decreased significantly ay all times. LDL-c concentrations decreased and differed between M1 and M2 (p = 0.001) and between M1 and M3 (p = 0.001). HDL-c values increased, however only differing between M1 and M2 (p = 0.050).

CONCLUSION

Roux-en-Y gastric bypass promoted a decrease in plasma concentrations of CRP and Alpha-1-acid glycoprotein, improving lipid and inflammatory profiles.

The short-term and long-term effects of bariatric/metabolic surgery on subcutaneous adipose tissue inflammation in humans

CONTEXT

The mechanisms mediating the short- and long-term improvements in glucose homeostasis following bariatric/metabolic surgery remain incompletely understood.

OBJECTIVE

To investigate whether a reduction in adipose tissue inflammation plays a role in the metabolic improvements seen after bariatric/metabolic surgery, both in the short-term and longer-term.

DESIGN

Fasting blood and subcutaneous abdominal adipose tissue were obtained before (n=14), at one month (n=9), and 6-12months (n=14) after bariatric/metabolic surgery from individuals with obesity who were not on insulin or anti-diabetes medication. Adipose tissue inflammation was assessed by a combination of whole-tissue gene expression and flow cytometry-based quantification of tissue leukocytes.

RESULTS

One month after surgery, body weight was reduced by 13.5±4.4kg (p<0.001), with improvements in glucose tolerance reflected by a decrease in area-under-the-curve (AUC) glucose in 3-h oral glucose tolerance tests (-105±98mmol/L * min; p=0.009) and enhanced pancreatic β-cell function (insulinogenic index: +0.8±0.9pmol/mmol; p=0.032), but no change in estimated insulin sensitivity (Matsuda insulin sensitivity index [ISI]; p=0.720). Furthermore, although biomarkers of systemic inflammation and pro-inflammatory gene expression in adipose tissue remained unchanged, the number of neutrophils increased in adipose tissue 15-20 fold (p<0.001), with less substantial increases in other leukocyte populations. By the 6-12month follow-up visit, body weight was reduced by 34.8±10.8kg (p<0.001) relative to baseline, and glucose tolerance was further improved (AUC glucose -276±229; p<0.001) along with estimated insulin sensitivity (Matsuda ISI: +4.6±3.2; p<0.001). In addition, improvements in systemic inflammation were reflected by reductions in circulating C-reactive protein (CRP; -2.0±5.3mg/dL; p=0.002), and increased serum adiponectin (+1358±1406pg/mL; p=0.003). However, leukocyte infiltration of adipose tissue remained elevated relative to baseline, with pro-inflammatory cytokine mRNA expression unchanged, while adiponectin mRNA expression trended downward (p=0.069).

CONCLUSION

Both the short- and longer-term metabolic improvements following bariatric/metabolic surgery occur without significant reductions in measures of adipose tissue inflammation, as assessed by measuring the expression of genes encoding key mediators of inflammation and by flow cytometric immunophenotyping and quantification of adipose tissue leukocytes.

The role of body mass index class in cholecystectomy after acute cholecystitis: An American College of Surgeons National Surgical Quality Improvement Program analysis

BACKGROUND

Obesity is a risk factor for cholelithiasis leading to acute cholecystitis which is treated with cholecystectomy. The purpose of this study was to analyze the associations between body mass index class and the intended operative approach (laparoscopic versus open) for and outcomes of cholecystectomy for acute cholecystitis.

METHODS

We conducted a retrospective cohort study using the American College of Surgeons National Surgical Quality Improvement Program data from 2008-2013. The effects of body mass index class on intended procedure type (laparoscopic versus open), conversion from laparoscopic to open operation, and outcomes after cholecystectomy were examined using multivariable logistic regression.

RESULTS

Data on 20,979 patients who underwent cholecystectomy for acute cholecystitis showed that 18,228 (87%) had a laparoscopic operation; 639 (4%) of these patients required conversion to an open approach; and 2,751 (13%) underwent intended open cholecystectomy. There was an independent association between super obesity (body mass index 50+) and an intended open operation (odds ratio 1.53, 95% confidence interval 1.14-2.05, P = .01). An intended open procedure (odds ratio 3.10, 95% confidence interval 2.40-4.02, P < .0001) and conversion (odds ratio 3.45, 95% confidence interval 2.16-5.50, P < .0001) were associated with increased risk of death/serious morbidity in a model, even when controlling for all other important factors. In the same model, body mass index class was not associated with increased death/serious morbidity. Outcomes after conversion were not substantially worse than outcomes after intended open cholecystectomy.

CONCLUSION

This study supports the possibility that an intended open approach to acute cholecystitis, not body mass index class, is associated with worse outcomes after cholecystectomy. An initial attempt at laparoscopy may benefit patients, even those at the highest end of the body mass index spectrum.

Sleeve gastrectomy versus Roux-en-Y gastric bypass for type 2 diabetes and morbid obesity: double-blind randomised clinical trial protocol

INTRODUCTION

Type 2 diabetes (T2D) in association with obesity is an increasing disease burden. Bariatric surgery is the only effective therapy for achieving remission of T2D among those with morbid obesity. It is unclear which of the two most commonly performed types of bariatric surgery, laparoscopic sleeve gastrectomy (LSG) and laparoscopic Roux-en-Y gastric bypass (LRYGB), is most effective for obese patients with T2D. The primary objective of this study is to determine whether LSG or LRYGB is more effective in achieving HbA1c<6% (<42 mmol/mol) without the use of diabetes medication at 5 years.

METHODS AND ANALYSIS

Single-centre, double-blind (assessor and patient), parallel, randomised clinical trial (RCT) conducted in New Zealand, targeting 106 patients. Eligibility criteria include age 20-55 years, T2D of at least 6 months duration and body mass index 35-65 kg/m(2) for at least 5 years. Randomisation 1:1 to LSG or LRYGB, used random number codes disclosed to the operating surgeon after induction of anaesthesia. A standard medication adjustment schedule will be used during postoperative metabolic assessments. Secondary outcomes include proportions achieving HbA1c<5.7% (39 mmol/mol) or HbA1c<6.5% (48 mmol/mol) without the use of diabetes medication, comparative weight loss, obesity-related comorbidity, operative complications, revision rate, mortality, quality of life, anxiety and depression scores. Exploratory outcomes include changes in satiety, gut hormone and gut microbiota to gain underlying mechanistic insights into T2D remission.

ETHICS AND DISSEMINATION

Ethics approval was obtained from the New Zealand regional ethics committee (NZ93405) who also provided independent safety monitoring of the trial. Study commenced in September 2011. Recruitment completed in October 2014. Data collection is ongoing. Results will be reported in manuscripts submitted to peer-reviewed journals and in presentations at national and international meetings.

TRIAL REGISTRATION NUMBERS

ACTRN12611000751976, NCT01486680; Pre-results.

Improvements in glycemic control after gastric bypass occur despite persistent adipose tissue inflammation

OBJECTIVE

Type 2 diabetes commonly goes into remission following Roux-en-Y gastric bypass (RYGB). As the mechanisms remain incompletely understood, a reduction in adipose tissue inflammation may contribute to these metabolic improvements. Therefore, whether RYGB reduces adipose tissue inflammation compared with equivalent weight loss from an intensive lifestyle intervention was investigated.

METHODS

Sixteen people with obesity and type 2 diabetes were randomized to RYGB or lifestyle intervention. Fasting blood and subcutaneous abdominal adipose tissue were obtained before and after the loss of ∼7% of baseline weight. Adipose tissue inflammation was assessed by whole-tissue gene expression and flow cytometry-based quantification of tissue leukocytes.

RESULTS

At 7% weight loss, insulin and metformin use were reduced among the RYGB but not the Lifestyle cohort, while fasting glucose and insulin declined in both. Adipose tissue inflammation increased modestly after RYGB and to a similar extent following nonsurgical weight loss. In both groups, the number of neutrophils increased severalfold (P < 0.001), mRNA levels of the proinflammatory cytokine interleukin-1β increased (P = 0.037), and mRNA expression of the anti-inflammatory and insulin-sensitizing adipokine adiponectin decreased (P = 0.010).

CONCLUSIONS

A reduction in adipose tissue inflammation is not one of the acute weight loss-independent mechanisms through which RYGB exerts its antidiabetes effects.

Psychopharmacology and Bariatric Surgery

Currently, it has been demonstrated that psychotropic drugs, particularly antidepressants, are frequently prescribed for patients who seek bariatric surgery. Many bariatric surgery patients have a history of a mood disorder. Unlike medications for diabetes, hypertension or hyperlipidemia, which are generally reduced and at times discontinued, postsurgery antidepressants use is only slightly reduced. The Roux-en-Y procedure is most frequently associated with alteration in drug exposure. Medication disintegration, dissolution, absorption, metabolism and excretion have been found to be altered in postbariatric patients, although data are sparse at this time. This paper will review the current evidence regarding the effect of bariatric surgery on drug treatment including mechanism of interference as well as the extent of changes identified to date. Data will be presented as controlled trials followed by case series and reports.

Predictors of metabolic syndrome persistence 1 year after laparoscopic Roux-en-Y gastric bypass

BACKGROUND

Laparoscopic Roux-en-Y gastric bypass (LRYGB) is effective in reversing the metabolic syndrome (MS) in up to 90% of patients.

OBJECTIVES

The aim of this study was to determine predictors of MS persistence 1 year after LRYGB.

SETTING

University Hospital, France.

METHODS

Ninety-one patients with a mean age of 44.4 years and a mean body mass index (BMI) of 43.1 kg/m² meeting the criteria for MS were enrolled in this prospective study. Anthropometric, metabolic, and inflammatory biological parameters were assessed before and 1 year after LRYGB. Patients were divided into 2 groups according to the persistence (MS nonresponders) or resolution of MS (MS responders) 1 year after LRYGB and a comparison was performed at baseline and 1 year after surgery.

RESULTS

Sixty-nine patients (75.8%) underwent remission, while 22 (24.2%) showed persistence of MS 1 year after LRYGB. At baseline the MS nonresponders group presented significantly higher values of fasting plasma glucose (7.8 versus 5.3 mmol/L, P = .004), glycosylated hemoglobin (HbA1c, 7.3% versus 5.9%, P = .0004), triglycerides (TG, 2.37 versus 1.33 mmol/L, P = .006), and homeostasis model assessment of insulin resistance (HOMA-IR, 442.5 versus 256, P = .006). The rate of diabetes was significantly higher in this group (68.2% versus 36.8%, P = .0086), as well as the number of MS components per patient. One year after LRYGB, the MS nonresponders showed a significantly lower excess BMI lost (EBMIL) (56.1% versus 82.4%, P = .00008). On multivariate analysis, baseline levels of TG, glucose metabolism markers and EBMIL were associated with the persistence of MS.

CONCLUSION

Baseline levels of TG, plasma fasting glucose, and HbA1c, as well as history of type 2 diabetes and EBMIL, represent predictors of MS persistence 1 year after LRYGB.

Excess body mass index loss predicts metabolic syndrome remission after gastric bypass

BACKGROUND

Metabolic syndrome (MS) is a condition associated with obesity that identifies individuals with increased cardiovascular risk. Gastric bypass improves several MS components, such as glucose, lipid metabolism and hypertension. The aim of this study was to evaluate the effect of long-limb gastric bypass on the remission of MS criteria associated with morbid obesity.

METHODS

Obese patients who met the "harmonized" criteria for MS (n = 153) that underwent laparoscopic Roux-en-Y gastric bypass (LRYGB) with a long biliopancreatic limb were prospectively evaluated with regards to body weight, body mass index (BMI), percentage of excess BMI lost (% EBMIL), fasting glucose, blood pressure and lipid profile up to 36 months after surgery.

RESULTS

Before surgery, patients had a BMI of 44.3 ± 0.5 kg/m2; 66% were under anti-diabetic treatment; 78.4% were under anti-hypertensive treatment and 44.3% were under anti-dyslipidemic treatment. After a mean follow-up time of 2.4 ± 0.1 years, MS remission rates were 32.7% at 6 months, 69.7% at 12 months, 63.4% at 24 months, and 59.2% at 36 months; when only 32.9%, 43.4% and 15.8% of patients were still under anti-diabetic, anti-hypertensive and anti-dyslipidemic treatment, respectively. The %EBMIL and BMI were the parameters that showed the highest accuracy to predict the MS remission at all-time points after the surgery.

CONCLUSIONS

Long limb gastric bypass in obese patients results in significant and sustained weight loss which predicts a high remission rate of MS and allows the discontinuation of drug therapy for several metabolic disturbances in most patients.

Effects of sleeve gastrectomy in high fat diet-induced obese mice: respective role of reduced caloric intake, white adipose tissue inflammation and changes in adipose tissue and ectopic fat depots

BACKGROUND

Sleeve gastrectomy (SG) has become a popular bariatric procedure. The mechanisms responsible for weight loss and improvement of metabolic disturbances have still not been completely elucidated. We investigated the effect of SG on body weight, adipose tissue depots, glucose tolerance, and liver steatosis independent of reduced caloric intake in high-fat-diet-induced obese mice.

METHODS

C57BI/6 J mice fed a high fat diet (45 %) for 33 weeks were divided into three groups: sleeve gastrectomy (SG, 13 mice), sham-operated ad libitum fed (SALF, 13 mice) and sham-operated pair fed (PFS, 13 mice). The animals were humanely killed 23 days after surgery.

RESULTS

In SG mice, food intake was reduced transiently, but weight loss was significant and persistent compared to controls (SG vs. PFS, P < 0.05; PFS vs. SALF, P < 0.05). SG mice showed improved glucose tolerance and lower levels of liver steatosis compared with controls (area under the curve, SG vs. PFS, P < 0.01; PFS vs. SALF, P < 0.05) (liver steatosis, SG vs. PFS, P < 0.05; PFS vs. SALF, P < 0.01). This was associated with a decrease in the ratios of the weight of pancreas, epididymal and inguinal adipose tissues to body weight, and an increase in the ratio of brown adipose tissue weight to body weight. Epididymal adipose tissue was also infiltrated by fewer activated T cells and by more anti-inflammatory regulatory T cells. Serum levels of fasting acyl ghrelin were still significantly decreased 3 weeks after surgery in SG mice compared to PFS mice (P < 0.05).

CONCLUSIONS

Reduced white adipose tissue inflammation, modification of adipose tissue development (brown vs. white adipose tissue), and ectopic fat are potential mechanisms that may account for the reduced caloric intake independent effects of SG.

Evolution of low-grade systemic inflammation, insulin resistance, anthropometrics, resting energy expenditure and metabolic syndrome after bariatric surgery: a comparative study between gastric bypass and sleeve gastrectomy

BACKGROUND

Laparoscopic sleeve gastrectomy (LSG) for morbid obesity is gaining in popularity as it offers several advantages over laparoscopic Roux-en-Y gastric bypass (LRYGBP), but comparative data between these two procedures have rarely been reported.

METHODS

This case control study compared the incidence of low-grade systemic inflammation, insulin resistance, anthropometrics, resting energy expenditure and metabolic syndrome in 30 patients undergoing LRYGBP and 30 patients undergoing LSG, matched for age, sex, body mass index (BMI), and glycosylated hemoglobin (HbA1c).

RESULTS

At 1-year after surgery, the percent of excess weight loss was 67.8 ± 20.9 for LRYGBP and 61.6 ± 19.4 for LSG. Patients undergoing LRYGBP showed significantly lower plasma levels of C-reactive protein (3.3 ± 2.7 mg/dL vs. 5.3 ± 3.9 mg/dL; P < 0.05), waist circumference (97.4 ± 16.0 vs. 105.5 ± 14.7 cm; P < 0.05), total cholesterol (4.6 ± 1.0 vs. 5.7 ± 0.9 mmol/L; P < 0.01) and LDL cholesterol (2.6 ± 0.8 vs. 3.6 ± 0.8 mmol/L; P < 0.01). Insulin resistance (HOMA index 1.6 ± 1.0 after LRYGBP vs. 2.3 ± 2.4 after LSG), resting energy expenditure (1666.7 ± 320.5 after LRYGBP vs. 1600.4 ± 427.3 Kcal after LSG) and remission of metabolic syndrome (92.9% after LRYGBP vs. 80% after LSG) were not different between the two groups.

CONCLUSION

In this study, patients undergoing LRYGBP demonstrated significantly improved lipid profiles, decreased systemic low-grade inflammation compared with those undergoing LSG at 1-year follow-up.

Relationship between acute phase proteins and serum fatty acid composition in morbidly obese patients

Background. Obesity is considered a low-grade inflammatory state and has been associated with increased acute phase proteins as well as changes in serum fatty acids. Few studies have assessed associations between acute phase proteins and serum fatty acids in morbidly obese patients. Objective. To investigate the relationship between acute phase proteins (C-Reactive Protein, Orosomucoid, and Albumin) and serum fatty acids in morbidly obese patients. Methods. Twenty-two morbidly obese patients were enrolled in this study. Biochemical and clinical data were obtained before bariatric surgery, and fatty acids measured in preoperative serum. Results. Orosomucoid was negatively correlated with lauric acid (P = 0.027) and eicosapentaenoic acid (EPA) (P = 0.037) and positively with arachidonic acid (AA) (P = 0.035), AA/EPA ratio (P = 0.005), and n-6/n-3 polyunsaturated fatty acids ratio (P = 0.035). C-Reactive Protein (CRP) was negatively correlated with lauric acid (P = 0.048), and both CRP and CRP/Albumin ratio were negatively correlated with margaric acid (P = 0.010, P = 0.008, resp.). Albumin was positively correlated with EPA (P = 0.027) and margaric acid (P = 0.008). Other correlations were not statistically significant. Conclusion. Our findings suggest that serum fatty acids are linked to acute phase proteins in morbidly obese patients.

Genome-wide association of single-nucleotide polymorphisms with weight loss outcomes after Roux-en-Y gastric bypass surgery

CONTEXT

Roux-en-Y gastric bypass (RYGB) is among the most effective treatments for extreme obesity and obesity-related complications. However, despite its potential efficacy, many patients do not achieve and/or maintain sufficient weight loss.

OBJECTIVE

Our objective was to identify genetic factors underlying the variability in weight loss outcomes after RYGB surgery.

DESIGN

We conducted a genome-wide association study using a 2-stage phenotypic extreme study design.

SETTING

Patients were recruited from a comprehensive weight loss program at an integrated health system.

PATIENTS

Eighty-six obese (body mass index >35 kg/m(2)) patients who had the least percent excess body weight loss (%EBWL) and 89 patients who had the most %EBWL at 2 years after surgery were genotyped using Affymetrix version 6.0 single-nucleotide polymorphism (SNP) arrays. A second group from the same cohort consisting of 164 patients in the lower quartile of %EBWL and 169 from the upper quartile were selected for evaluation of candidate regions using custom SNP arrays.

INTERVENTION

We performed RYGB surgery.

MAIN OUTCOME MEASURES

We assessed %EBWL at 2 years after RYGB and SNPs.

RESULTS

We identified 111 SNPs in the first-stage analysis whose frequencies were significantly different between 2 phenotypic extremes of weight loss (allelic χ(2) test P < .0001). Linear regression of %EBWL at 2 years after surgery revealed 17 SNPs that approach P < .05 in the validation stage and cluster in or near several genes with potential biological relevance including PKHD1, HTR1A, NMBR, and IGF1R.

CONCLUSIONS

This is the first genome-wide association study of weight loss response to RYGB. Variation in weight loss outcomes after RYGB may be influenced by several common genetic variants.

Effects of bariatric surgery on adipokine-induced inflammation and insulin resistance

Over a third of the US population is obese and at high risk for developing type 2 diabetes, insulin resistance, and other metabolic disorders. Obesity is considered a chronic low-grade inflammatory condition that is primarily attributed to expansion and inflammation of adipose tissues. Indeed, adipocytes produce and secrete numerous proinflammatory and anti-inflammatory cytokines known as adipokines. When the balance of these adipokines is shifted toward higher production of proinflammatory factors, local inflammation within adipose tissues and subsequently systemic inflammation occur. These adipokines including leptin, visfatin, resistin, apelin, vaspin, and retinol binding protein-4 can regulate inflammatory responses and contribute to the pathogenesis of diabetes. These effects are mediated by key inflammatory signaling molecules including activated serine kinases such as c-Jun N-terminal kinase and serine kinases inhibitor κB kinase and insulin signaling molecules including insulin receptor substrates, protein kinase B (PKB, also known as Akt), and nuclear factor kappa B. Bariatric surgery can decrease body weight and improve insulin resistance in morbidly obese subjects. However, despite reports suggesting reduced inflammation and weight-independent effects of bariatric surgery on glucose metabolism, mechanisms behind such improvements are not yet well understood. This review article focuses on some of these novel adipokines and discusses their changes after bariatric surgery and their relationship to insulin resistance, fat mass, inflammation, and glucose homeostasis.

Efficiency of laparoscopic sleeve gastrectomy on metabolic syndrome disorders: two years results

OBJECTIVES

There are very few studies evaluating the efficacy of sleeve gastrectomy on the metabolic syndrome, truly a worldwide pandemic. The main objective of this study was to retrospectively determine the evolution of the metabolic syndrome and its associated comorbidities (type 2 diabetes, arterial hypertension, and dyslipidemia) at 24 months after sleeve gastrectomy. The secondary objective was to determine the predictive factors for resolution of this syndrome.

MATERIAL AND METHODS

Between July 2004 and February 2008, 241 patients with morbid obesity (males: 17%) underwent sleeve gastrectomy in our center. Patients were seen in combined medical and surgical outpatient postoperative follow-up consultation at 3, 6, 12 and 24 months. Patients were classed as responders or not, according to whether or not the metabolic syndrome (as defined according to the National Cholesterol Education Program-Adult Treatment Panel III [NCEP-ATPIII]) disappeared at 24 months follow-up.

RESULTS

Thirty-six patients (15% of all patients, 30% of males) presented initially with metabolic syndrome. Twenty-six patients (72%) still had metabolic syndrome at 6 months, 17 patients (47%) at 12 months, and 13 patients (36%) at 24 months. The main parameters that regressed after sleeve gastrectomy were type 2 diabetes and hypertriglyceridemia. In univariate analysis, only one parameter (systolic blood pressure) appeared to be a factor of non-resolution of the metabolic syndrome at 24 months.

CONCLUSION

Our study showed that sleeve gastrectomy reduced the incidence of the metabolic syndrome and several of its components.

The duodenal switch for morbid obesity: modification of cardiovascular risk markers compared with standard bariatric surgeries

BACKGROUND

Obesity is associated with cardiovascular risk factors such as lipid levels and increased levels of C-reactive peptide (CRP). We hypothesized that duodenal switch (DS) would show equivalent or superior risk reduction compared with standard bariatric surgeries.

METHODS

Patients underwent DS, sleeve gastrectomy (SG), or gastric bypass (GB) over a 2-year period. Body mass index (BMI), lipid panel, and CRP were measured preoperatively and then 3, 6, and 12 months postoperatively.

RESULTS

A total of 130 patients were identified; 42 underwent DS, 40 underwent SG, and 48 underwent GB. All groups had similar sex and comorbidity profiles, but the mean preoperative BMI was greatest in the DS group (mean = 52). At all intervals weight loss was greater in the DS group (P < .01), with a final BMI of 31 for the DS group, 31 for the SG group, and 28 for the GB group. Cholesterol and low-density lipoprotein showed significantly greater improvement at all time points with DS compared with SG and GB (P < .01). Baseline CRP levels among DS patients were double that of SG and GB, but rapidly declined to equivalent levels by 3 months and normalized in 79%.

CONCLUSIONS

The DS procedure resulted in a superior reduction in cardiovascular and proinflammatory risk markers compared with GB and SG.

Metabolic syndrome after bariatric surgery. Results depending on the technique performed

BACKGROUND

There is a lack of long-term studies for metabolic syndrome after bariatric surgery. Our aim is to show the evolution of the parameters that define the metabolic syndrome after bariatric surgery, up to 10 years of follow-up, in order to clarify what technique gets better results with fewer complications.

METHODS

The IDF definition of the metabolic syndrome was used for this study. One hundred twenty-five morbid obese and superobese patients underwent vertical banded gastroplasty. Two hundred sixty-five morbid obese and superobese patients had biliopancreatic diversion (Scopinaro and modified biliopancreatic diversions), and 152 morbid obese patients underwent laparoscopic gastric bypass. A mean follow-up of up to 7 years was done in all groups.

RESULTS

Prior to surgery, metabolic syndrome was diagnosed in 114 patients of Scopinaro group (76%), in 85 patients of modified biliopancreatic diversion group (73.9%), in 81 patients of laparoscopic gastric bypass (53.4%), and in 98 patients of vertical banded gastroplasty (78.4%). When metabolic syndrome parameters were evaluated at 7 years of follow-up, owing to weight gain, these results changed nearby to preoperative values in both laparoscopic gastric bypass and vertical banded gastroplasty groups.

CONCLUSION

According to our results, the best technique to resolve metabolic syndrome is the modified biliopancreatic diversion. Due to its high morbidity, it only must be considered in superobese patients. In obese patients, the laparoscopic gastric bypass may be a less agressive choice, but it should be coupled with lifestyle changes to keep away from the weight gain in the long run. Restrictive procedures may be indicated only in a few well-selected cases.

Serial changes in inflammatory biomarkers after Roux-en-Y gastric bypass surgery

BACKGROUND

A number of proteins secreted from adipose tissue, known as adipokines, are involved in the inflammatory process. The expression and secretion of adipokines are altered with obesity, leading to a pro-inflammatory state, with an enhanced vascular immune response. Although weight loss reduces inflammation, the time course for these changes during massive weight loss after bariatric surgery is not well described. We examined the changes in the biomarkers of inflammation after laparoscopic Roux-en-Y gastric bypass (RYGB) in morbidly obese individuals in a university hospital.

METHODS

The fasting levels of plasma inflammatory adipokines, including leptin, adiponectin, C-reactive protein (CRP), interleukin-6, tumor necrosis factor-α (TNF-α), and soluble receptor 1 for TNF-α were measured before surgery (baseline) and 3 weeks, 3 months, and 6 months after surgery in 15 morbidly obese patients who underwent Roux-en-Y gastric bypass without a major complication.

RESULTS

The mean weight loss at 6 months was 25.7% ± 4.5% of the total body weight. The body mass index decreased from a mean of 55.1 ± 6.6 kg/m(2) to 40.5 ± 5.5 kg/m(2). The concentrations of leptin, CRP, and soluble receptor 1 for TNF-α decreased, and the adiponectin levels had increased from the baseline measures by 6 months postoperatively. The baseline and 6-month TNF-α and CRP levels correlated with each other. No other significant associations among the biomarkers were seen.

CONCLUSION

RYGB reduced the pro-inflammatory biomarkers and increased the anti-inflammatory mediators of obesity, independent of the magnitude of weight loss. The lack of correlations between the changes in biomarkers and weight loss suggests that the driving force behind the changes in the inflammatory markers is multifactorial and needs further investigation to clarify the health changes that occur after RYGB.

Reversal of inflammation-induced impairment of glucose uptake in adipocytes by direct effect of CB1 antagonism on adipose tissue macrophages

Macrophage infiltration into adipose tissue (AT-MP) is thought to induce insulin resistance and diabetes in obesity. Here, we investigated the effect of the antiobesity drug SR141716 (a CB1 antagonist) on macrophage-mediated inhibition of insulin signaling in adipocytes. THP1 macrophages (THP1) were stimulated in vitro with lipopolysaccharide (LPS) and SR141716 or vehicle. The resulting conditioned medium (CM) was analyzed and incubated on human adipocytes. CM from LPS-stimulated THP1 inhibited insulin-induced AKT phosphorylation in adipocytes, in contrast to CM from nonactivated THP1. Moreover, it contained higher concentrations of tumor necrosis factor-α (TNFα) and lower levels of the anti-inflammatory cytokine IL-10. SR141716 reduced TNFα production and increased IL-10 secretion, resulting in a rescue of insulin signaling in adipocytes. To confirm these findings in vivo, AT-MP CM from cafeteria diet-fed or Zucker diabetic fatty (ZDF) rats that had received SR141716 for 3 weeks were isolated, analyzed, and incubated with adipocytes. Cafeteria diet induced macrophage-mediated inhibition of insulin signaling in adipocytes. Interestingly, SR141716 rescued insulin-induced glucose uptake in adipocytes. Finally, AT-MP CM from obese ZDF rats inhibited insulin-stimulated glucose uptake in adipocytes in contrast to AT-MP CM from lean ZDF rats. After treatment with SR141716, AT-MP CM rescued insulin-induced glucose uptake in adipocytes. In summary, our data indicate that CB1 receptor antagonism in macrophages modified their cytokine production and improved the insulin responsiveness of adipocytes that had been incubated with macrophage CM. Thus, SR141716 ameliorated adipose tissue insulin resistance by direct action on AT-MP demonstrating a novel peripheral mode of action of CB1 antagonism.

Bariatric surgery and its impact on sleep architecture, sleep-disordered breathing, and metabolism

Over the last several decades, the prevalence of obesity has increased significantly worldwide. This has translated into an increased prevalence of obesity-associated morbidities including sleep-disordered breathing and metabolic disorders. While the medical management of obesity is relatively ineffective, bariatric surgery is the most successful method for sustained weight loss and markedly reduces obesity-related morbidity and mortality. The anatomical changes created with different types of procedures lead to variable weight loss and improvement of co-morbidities; however the latter does not appear to be exclusively dependent on the amount of weight loss. Bariatric surgery does not always lead to complete resolution of obstructive sleep apnea and age, gender and severity of the obstructive sleep apnea predict the residual disease after peak weight loss. Metabolic disorders and specifically diabetes often improve dramatically early after the procedure, before any significant weight loss has occurred. The modified gastrointestinal anatomy and physiology may explain this phenomenon.

Obesity in older mothers, gestational weight gain, and risk estimates for preterm phenotypes

OBJECTIVE

To assess whether advanced maternal age modifies the relationship between maternal pregravid weight status, gestational weight gain patterns, and the occurrence of spontaneous preterm birth (SPB) and medically indicated preterm birth (MIPB).

METHODS

Retrospective cohort analysis of vital statistics data from the state of Florida for the period 2004 through 2007 comprising 311,422 singleton pregnancies (two age groups: 20-24 years old or younger women and >or=35 years or older women). Mothers were classified into five clusters based on their pre-pregnancy body mass index (BMI) values: non-obese (less than 30), class I obese (30.0<or=BMI<or=34.9), class II obese (35.0<or=BMI<or=39.9), class III obese (40<or=BMI<or=49.9), and super-obese (BMI>or=50.0).

RESULTS

MIPB occurred more frequently among older than younger women [11.8% vs. 6.4%, respectively (p<0.0001)) whereas SPB occurred more frequently among younger women [11.3% vs. 10.5%, respectively (p<0.0001)). Maternal obesity increased the risk for MIPB but not for SPB. Regardless of BMI status, the risk of MIPB was elevated among older mothers, particularly among those with suboptimal (<0.23 kg/week) and supraoptimal (>0.68 kg/week) gestational weight gain. A dose-response relationship with increasing gestational weight gain was evident (p<0.01); the greatest risk for MIPB occurred among older mothers with weekly gestational weight gain in excess of 0.79 kg (OR=7.76, 95% CI=5.73-10.5).

CONCLUSION

The occurrence of medically indicated preterm birth is positively associated with increased maternal pregravid body weight, older maternal age and extremes of gestational weight gain. Targeted pre- and inter-conception weight management efforts should be particularly encouraged in older mothers.

Endocrine and metabolic response to gastric bypass

PURPOSE OF REVIEW

Diabetes resolves in 80% of individuals undergoing successful Roux-en-Y gastric bypass. Absolute caloric restriction alone resulting from gastric anatomic changes indeed leads to weight loss; however, immediate effects in glycemic control often precede substantial weight loss typically associated with insulin sensitivity. One putative explanation relates to hormonal effects accompanying Roux-en-Y gastric bypass. We reviewed the existing and recent literature to investigate the hormonal changes accompanying Roux-en-Y gastric bypass.

RECENT FINDINGS

Changes in levels of five candidate enteric hormones have been recently associated with early postoperative glycemic control following Roux-en-Y gastric bypass; the strongest effects are seen with variations in glucagon-like peptide-1, glucose-dependent insulinotropic peptide and ghrelin.

SUMMARY

The unique hybridization of static anatomic restriction and dynamic absorptive bypass lends a duality to the beneficial effects of Roux-en-Y gastric bypass. This duality likely explains the short-term and long-term resolution of diabetes in patients undergoing Roux-en-Y gastric bypass.