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Background: Vagal nerve blockade (vBloc) therapy was shown to be a safe and effective treatment for moderate to severe obesity. This report summarizes the safety and efficacy of vBloc therapy in the prespecified subgroup of patients with moderate obesity., Methods: The ReCharge Trial is a double-blind, randomized controlled clinical trial of participants with body mass index (BMI) of 40-45 or 35-40 kg/m(2) with at least one obesity-related comorbid condition. Participants were randomized 2:1 to implantation with either a vBloc or sham device with weight management counseling. Eighty-four subjects had moderate obesity (BMI 35-40 kg/m(2)) at randomization., Results: Fifty-three participants were randomized to vBloc and 31 to sham. Qualifying obesity-related comorbidities included dyslipidemia (73%), hypertension (58%), sleep apnea (33%), and type 2 diabetes (8%). The vBloc group achieved a percentage excess weight loss (%EWL) of 33% (11% total weight loss (%TWL)) compared to 19% EWL (6% TWL) with sham at 12 months (treatment difference 14 percentage points, 95% CI, 7-22; p < 0.0001). Common adverse events of vBloc through 12 months were heartburn/dyspepsia and implant site pain; the majority of events were reported as mild or moderate., Conclusions: vBloc therapy resulted in significantly greater weight loss than the sham control among participants with moderate obesity and comorbidities with a well-tolerated safety profile.

Background/objectives: Vagal block therapy (vBloc) is effective for moderate to severe obesity at one year., Subjects/methods: The ReCharge trial is a double-blind, randomized controlled clinical trial of 239 participants with body mass index (BMI) of 40 to 45 kg/m or 35 to 40 kg/m with one or more obesity-related conditions. Interventions were implantation of either vBloc or Sham devices and weight management counseling. Mixed models assessed percent excess weight loss (%EWL) and total weight loss (%TWL) in intent-to-treat analyses. At 18 months, 142 (88%) vBloc and 64 (83%) Sham patients remained enrolled in the study., Results: 18-month weight loss was 23% EWL (8.8% TWL) for vBloc and 10% EWL (3.8% TWL) for Sham (P < 0.0001). vBloc patients largely maintained 12-month weight loss of 26% EWL (9.7% TWL). Sham regained over 40% of the 17% EWL (6.4% TWL) by 18 months. Most weight regain preceded unblinding. Common adverse events of vBloc through 18 months were heartburn/dyspepsia and abdominal pain; 98% of events were reported as mild or moderate and 79% had resolved., Conclusions: Weight loss with vBloc was sustained through 18 months, while Sham regained weight between 12 and 18 months. vBloc is effective with a low rate of serious complications.

Rapid shifts in the demographics and techniques of weight loss surgery (WLS) have led to new issues, new data, new concerns, and new challenges. In 2004, this journal published comprehensive evidence-based guidelines on WLS. In this issue, we've updated those guidelines to assure patient safety in this fast-changing field. WLS involves a uniquely vulnerable population in need of specialized resources and ongoing multidisciplinary care. Timely best-practice updates are required to identify new risks, develop strategies to address them, and optimize treatment. Findings in these reports are based on a comprehensive review of the most current literature on WLS; they directly link patient safety to methods for setting evidence-based guidelines developed from peer-reviewed scientific publications. Among other outcomes, these reports show that WLS reduces chronic disease risk factors, improves health, and confers a survival benefit on those who undergo it. The literature also shows that laparoscopy has displaced open surgery as the predominant approach; that government agencies and insurers only reimburse procedures performed at accredited WLS centers; that best practice care requires close collaboration between members of a multidisciplinary team; and that new and existing facilities require wide-ranging changes to accommodate growing numbers of severely obese patients. More than 100 specialists from across the state of Massachusetts and across the many disciplines involved in WLS came together to develop these new standards. We expect them to have far-reaching effects of the development of health care policy and the practice of WLS.

Background: To compare implantable gastric stimulation therapy with a standard diet and behavioral therapy regimen in a group of carefully selected class 2 and 3 obese subjects by evaluating the difference in the percentage of excess weight loss (EWL) between the control and treatment groups. The primary endpoint was the percentage of EWL from baseline to 12 months after randomization. Implantable gastric stimulation has been proposed as a first-line treatment for severely obese patients; however, previous investigations have reported inconclusive results., Methods: A total of 190 subjects were enrolled in this prospective, randomized, placebo-controlled, double-blind, multicenter study. All patients underwent implantation with the implantable gastric stimulator and were randomized to 1 of 2 treatment groups: the control group (stimulation off) or treatment group (stimulation on). The patients were evaluated on a monthly basis. All individuals who enrolled in this study agreed to consume a diet with a 500-kcal/d deficit and to participate in monthly support group meetings., Results: The procedure resulted in no deaths and a low complication rate. The primary endpoint of a difference in weight loss between the treatment and control groups was not met. The control group lost 11.7% +/- 16.9% of excess weight and the treatment group lost 11.8% +/- 17.6% (P = .717) according to an intent-to-treat analysis., Conclusion: Implantable gastric stimulation as a surgical option for the treatment of morbid obesity is a less complex procedure than current bariatric operations. However, the results of the present study do not support its application. Additional research is indicated to understand the physiology and potential benefits of this therapy.

With the epidemic of obesity worldwide, bariatric surgery has rapidly grown in popularity. Currently, a variety of surgical procedures are performed including Roux-en-Y gastric bypass, laparoscopic adjustable gastric banding, vertical banded gastroplasty, and biliopancreatic diversion. All of these procedures have been shown to succeed in achieving significant and sustainable weight loss for the majority of patients. However, these procedures also carry the potential for serious operative morbidity, altered gastrointestinal anatomy or function, or both. Electrical gastric stimulation via the implantable gastric stimulation (IGS) system is a relatively new and novel approach to treat obesity. The operative technique is relatively simple and the system does not alter gastrointestinal anatomy. Preliminary worldwide investigations have demonstrated safety and efficacy. This article will review the current experience with the IGS system.

Background: Little is known about the determinants of individual variability in body weight and fat loss after gastric bypass surgery or about the effects of massive weight loss induced by this surgery on energy requirements., Objectives: The objectives were to determine changes in energy expenditure and body composition with weight loss induced by gastric bypass surgery and to identify presurgery predictors of weight loss., Design: Thirty extremely obese women and men with a mean (+/- SD) age of 39.0 +/- 9.6 y and a body mass index (BMI; in kg/m(2)) of 50.1 +/- 9.3 were tested longitudinally under weight-stable conditions before surgery and after weight loss and stabilization (14 +/- 2 mo). Total energy expenditure (TEE), resting energy expenditure (REE), body composition, and fasting leptin were measured., Results: Subjects lost 53.2 +/- 22.2 kg body weight and had significant decreases in REE (-2.4 +/- 1.0 MJ/d; P < 0.001) and TEE (-3.6 +/- 2.5 MJ/d; P < 0.001). Changes in REE were predicted by changes in fat-free mass and fat mass. The average physical activity level (TEE/REE) was 1.61 at both baseline and follow-up (P = 0.98). Weight loss was predicted by baseline fat mass and BMI but not by any energy expenditure variable or leptin. Measured REE at follow-up was not significantly different from predicted REE., Conclusions: TEE and REE decreased by 25% on average after massive weight loss induced by gastric bypass surgery. REE changes were predicted by loss of body tissue; thus, there was no significant long-term change in energy efficiency that would independently promote weight regain.

Body composition methods were examined in 20 women [body mass index (BMI) 48.7 +/- 8.8 kg/m(2)] before and after weight loss [-44.8 +/- 14.6 (SD) kg] after gastric bypass (GBP) surgery. The reference method, a three-compartment (3C) model using body density by air displacement plethysmography and total body water (TBW) by H(2)18O dilution (3C-H(2)18O), showed a decrease in percent body fat (%BF) from 51.4 to 34.6%. Fat-free mass hydration was significantly higher than the reference value (0.738) in extreme obesity (0.756; P < 0.001) but not after weight reduction (0.747; P = 0.16). %BF by H(2)18O dilution and air displacement plethysmography differed significantly from %BF by 3C-H(2)18O in extreme obesity (P < 0.05) and 3C models using (2)H(2)O or bioelectrical impedance analysis (BIA) to determine TBW improved mean %BF estimates over most other methods at both time points. BIA results varied with the equation used, but BIA better predicted %BF than did BMI at both time points. All methods except BIA using the Segal equation were comparable to the reference method for determining changes over time. A simple 3C model utilizing air displacement plethysmography and BIA is useful for clinical evaluation in this population.

Objective: This study aimed to survey international experts in metabolic and bariatric surgery (MBS) to improve and consolidate the management of biliary disease in patients with severe obesity undergoing MBS. Background: Obesity and rapid weight loss after MBS are risk factors for the development of gallstones. Complications, such as cholecystitis, acute cholangitis, and biliary pancreatitis, are potentially life-threatening, and no guidelines for the proper management of gallstone disease exist. Methods: An international scientific team designed an online confidential questionnaire with 26 multiple-choice questions. The survey was answered by 86 invited experts (from 38 different countries), who participated from August 1, 2023, to September 9, 2023. Results: Two-thirds of experts (67.4%) perform concomitant cholecystectomy in symptomatic gallstones during MBS. Half of experts (50%) would wait 6–12 weeks between both surgeries with an interval approach. Approximately 57% of the experts prescribe ursodeoxycholic acid (UDCA) prophylactically after MBS, and most recommend a 6-month course. More than the half of the experts (59.3%/53.5%) preferred laparoscopic assisted transgastric ERCP as the approach for treating CBD stones in patients who previously had RYGB/OAGB. Conclusion: Concomitant cholecystectomy is preferred by the experts, although evidence in the literature reports an increased complication rate. Prophylactic UDCA should be recommended to every MBS patient, even though the current survey demonstrated that not all experts are recommending it. The preferred approach for treating common bile duct stones is a laparoscopic assisted transgastric ERCP after gastric bypass. The conflicting responses will need more scientific work and clarity in the future. [ABSTRACT FROM AUTHOR]

Patients are increasingly referred for conversion of laparoscopic adjustable gastric band (LAGB) to laparoscopic Roux-en-Y gastric bypass (LRYGB) or sleeve gastrectomy (SG). The safety of a 1- versus 2-stage approach to this revision is debated. We examined the safety and efficacy of 1-stage conversion of LAGB to SG at our institution. University hospital. An institutional database was used to retrospectively identify patients who underwent single-stage LAGB-to-SG conversion between 2010 and 2018. Patients were matched 1:1 for age, sex, and body mass index with primary SG patients during this same period. Primary endpoints were operative time, complication rate, length of hospital say, and weight loss 12 months from surgery. Two-hundred and twenty-nine patients undergoing conversion of LAGB to SG were identified. Median postoperative length of hospital stay was 2 days. Two patients (.8%) developed surgical site infection. One patient (.4%) developed a postoperative myocardial infarction. There were 4 total readmissions (1.7%) and 1 reoperation within 30 days (.4%). There were no statistically significant differences in 30-day complication rates between groups. Weight loss at 12 months was significantly different: Median body mass index loss for conversion patients was 5.1 kg/m2 compared with 8.85 kg/m2 for patients in the primary SG group (P <.0001). Single-stage conversion of LAGB to SG is safe and effective. Patients may not experience the same extent of weight loss as those with primary SG. Our findings represent the largest single-institutional experience to date and support a 1-stage approach whenever feasible. • Conversion of LAGB to SG in a single stage appears safe. • Weight loss after conversion of LAGB to SG may not be as effective as seen with primary SG. [ABSTRACT FROM AUTHOR]

Background: Single anastomosis sleeve ileal (SASI) bypass is a newly introduced bariatric and metabolic procedure. The present multicenter study aimed to evaluate the efficacy of the SASI bypass in the treatment of patients with morbid obesity and the metabolic syndrome. Methods: This is a retrospective, seven-country, multicenter study on patients with morbid obesity who underwent the SASI bypass. Data regarding patients' demographics, body mass index (BMI), percentage of total weight loss (%TWL), percentage of excess weight loss (%EWL), and improvement in comorbidities at 12 months postoperatively and postoperative complications were collected. Results: Among 605 patients who underwent the SASI, 54 were excluded and 551 (390; 70.8% female) were included. At 12 months after the SASI, a significant decrease in the BMI was observed (43.2 ± 12.5 to 31.2 ± 9.7 kg/m2; p < 0.0001). The %TWL was 27.4 ± 13.4 and the %EWL was 63.9 ± 29.5. Among the 279 patients with type 2 diabetes mellitus (T2DM), complete remission was recorded in 234 (83.9%) patients and partial improvement in 43 (15.4%) patients. Eighty-six (36.1%) patients with hypertension, 104 (65%) patients with hyperlipidemia, 37 (57.8%) patients with sleep apnea, and 70 (92.1%) patients with GERD achieved remission. Fifty-six (10.1%) complications and 2 (0.3%) mortalities were recorded. Most complications were minor. All patients had 12 months follow-up. Conclusions: The SASI bypass is an effective bariatric and metabolic surgery that achieved satisfactory weight loss and improvement in medical comorbidities, including T2DM, hypertension, sleep apnea, and GERD, with a low complication rate. [ABSTRACT FROM AUTHOR]

Background: Laparoscopic sleeve gastrectomy (LSG) is a well-established bariatric procedure. A staple line leak is a recognized complication of LSG. Bougie size has been suggested to impact leak rates. In this study, we evaluate the impact of using 32–34F bougie sizes with LSG on early postoperative outcomes including staple line leaks within our practice. Methods: This is a retrospective cohort analysis of a prospectively maintained database of all LSG procedures performed between January 2012 and December 2018 at a single medical center. Data collected and analyzed included bougie size, postoperative leak rate, need for re-operation, 12-month excess weight loss, and 30-day morbidity and mortality. Results: During the study period, 3153 patients underwent LSG, of whom 1977 (62.7%) were female. Mean age and body mass index (BMI) were 42.9 ± 12.2 years (range 15–76 years) and 42.4 ± 5.2 kg/m2 (range 27–73), respectively. No intraoperative complications or mortality occurred. There was one case of perioperative mortality due to bleeding (0.03%). Early postoperative adverse events occurred in 131 patients (4.1%): 17 leaks (0.5%), 75 bleeds (2.4%), and 39 (1.2%) other. Conclusion: The use of smaller-sized (32–34F) bougies had no impact on staple line leaks in the hands of experienced bariatric surgeons at a high-volume center. [ABSTRACT FROM AUTHOR]

Objective: The effects of sleeve gastrectomy (SG) on functional connectivity (FC) and associations with weight loss and eating-related cognitive control were investigated.Methods: In a longitudinal study, 14 SG patients (13 female; 42.1 presurgery BMI) completed study visits 1 month pre surgery and 12 months post surgery. Patients completed the Dutch Eating Behavior Questionnaire and resting-state functional magnetic resonance imaging scanning to measure FC. Data were analyzed using a seed-to-voxel approach in the CONN Toolbox to investigate pre-/postsurgery changes (n = 12) and to conduct predictive analysis (n = 14).Results: Seed-to-voxel analysis revealed changes in magnitude (decreases) and directionality (positively correlated to anticorrelated) of FC pre to post surgery within and between default mode network, salience network, and frontoparietal network nodes [Family-Wise Error (FWE) corrected at P < 0.05]. Baseline FC of the nucleus accumbens (with insula) and hypothalamus (with precentral gyrus) predicted 12-month post-SG % total weight loss (FWE-P < 0.05). Baseline FC of the hippocampus, frontoparietal network, and default mode network nodes predicted improvement in cognitive control of eating behavior 12 months after SG (FWE-P < 0.05).Conclusions: Our findings demonstrate changes in FC magnitude and directionality post versus pre surgery within and between resting-state networks and frontal, paralimbic, and visual areas in SG patients. Baseline FC predicted weight loss and changes in cognitive control of food intake behavior at 12 months. These could serve as predictive biomarkers for bariatric surgery. [ABSTRACT FROM AUTHOR]

Background: Of patients undergoing Roux-en-Y gastric bypass (RYGB), 15-35% of patients fail to achieve "adequate" weight loss or regain significant weight. Multiple solutions have been proposed, but not well studied. We report our experience with limb distalization with lengthening the biliopancreatic (BP) limb and shortening the common channel (CC).Methods: We retrospectively reviewed data from patients undergoing laparoscopic limb distalization for excess weight loss (EWL) <50% or BMI >35 kg/m2 after RYGB from 2012 to 2017. The BP limb was lengthened and CC was shortened to 100-200 cm. Perioperative outcomes such as morbidity, weight loss, nutritional deficiencies, comorbidity remission, and operative details were analyzed.Results: Twenty-two patients were included. The mean BMI prior to RYGB was 54.1 ± 8.5 kg/m2 and 43.0 ± 5.5 kg/m2 prior to limb distalization. The mean follow-up was 18.3 ± 12.9 months with a mean BMI change, %EWL, and %TWL (total weight loss) of 11.8 ± 7.4 kg/m2, 62.3 ± 32.4%, and 25.4 ± 14.4%, respectively. The total mean BMI change, %EWL, and %TWL from RYGB was 22.2 ± 9.9 kg/m2, 77.8 ± 23.6%, and 40.2 ± 13.3%, respectively. Of patients with persistent comorbidities, remission rates of diabetes, hypertension, and gastroesophageal reflux disease were 100%, 17%, and 38%, respectively. The mean operative time was 132.6 ± 54.4 min and mean hospital stay was 2.2 ± 1.3 days. Overall morbidity was 27.3%. Three patients (13.6%) developed nutritional deficiencies requiring reversal surgery.Conclusion: In patients with inadequate weight loss or weight regain after RYGB, limb distalization with lengthening of the BP limb is an effective procedure for additional weight loss and further improvement of comorbidities. Nutritional complications are a risk, but can be minimized with close follow-up and patient compliance. [ABSTRACT FROM AUTHOR]

Weight loss surgery, also referred to as bariatric surgery, has been in existence since the 1950's. Over the decades, it has been demonstrated to successfully achieve meaningful and sustainable weight loss in a large number of patients who undergo these procedures. Additionally, the benefits observed across a number of metabolic disorders such as type 2 diabetes mellitus and hyperlipidemia, are often to a degree, independent of the weight loss, thus the term “metabolic bariatric surgery (MBS)” has become a better descriptor. Throughout its long history, MBS has evolved from an era of high morbidity and mortality to one of laudable safety despite the high-risk nature of the patients undergoing these major gastrointestinal procedures. This article will describe the historic evolution of MBS and concentrate on those events that were instrumental in reducing the morbidity of these operations. [ABSTRACT FROM AUTHOR]

Background: The ReCharge Trial demonstrated that a vagal blocking device (vBloc) is a safe and effective treatment for moderate to severe obesity. This report summarizes 24-month outcomes. Methods: Participants with body mass index (BMI) 40 to 45 kg/m, or 35 to 40 kg/m with at least one comorbid condition were randomized to either vBloc therapy or sham intervention for 12 months. After 12 months, participants randomized to vBloc continued open-label vBloc therapy and are the focus of this report. Weight loss, adverse events, comorbid risk factors, and quality of life (QOL) will be assessed for 5 years. Results: At 24 months, 123 (76 %) vBloc participants remained in the trial. Participants who presented at 24 months ( n = 103) had a mean excess weight loss (EWL) of 21 % (8 % total weight loss [TWL]); 58 % of participants had ≥5 % TWL and 34 % had ≥10 % TWL. Among the subset of participants with abnormal preoperative values, significant improvements were observed in mean LDL (−16 mg/dL) and HDL cholesterol (+4 mg/dL), triglycerides (−46 mg/dL), HbA1c (−0.3 %), and systolic (−11 mmHg) and diastolic blood pressures (−10 mmHg). QOL measures were significantly improved. Heartburn/dyspepsia and implant site pain were the most frequently reported adverse events. The primary related serious adverse event rate was 4.3 %. Conclusions: vBloc therapy continues to result in medically meaningful weight loss with a favorable safety profile through 2 years. Trial Registration: [ABSTRACT FROM AUTHOR]

Class I obesity conveys an increased risk of comorbidities, impairs physical and mental health-related quality of life, and it is associated to an increased psychosocial burden, particularly in women. The need for effective and safe therapies for class I obesity is great and not yet met by nonsurgical approaches. Eligibility to bariatric surgery has been largely based on body mass index (BMI) cut points and limited to patients with more severe obesity levels. However, obese patients belonging to the same BMI class may have very different levels of health, risk, and impact of obesity on quality of life. Individual patients in class I obesity may have a comorbidity burden similar to, or greater than, patients with more severe obesity. Therefore, the denial of bariatric surgery to a patient with class I obesity suffering from a significant obesity-related health burden and not achieving weight control with nonsurgical therapy simply on the basis of the BMI level does not appear to be clinically justified. A clinical decision should be based on a more comprehensive evaluation of the patient's current global health and on a more reliable prediction of future morbidity and mortality. After a careful review of available data about safety and efficacy of bariatric surgery in patients with class I obesity, this panel reached a consensus on ten clinical recommendations. [ABSTRACT FROM AUTHOR]

To update evidence-based best practice guidelines for surgical care in weight loss surgery (WLS). Systematic search of English-language literature on WLS in MEDLINE, EMBASE, and the Cochrane Library between April 2004 and May 2007. Use of key words to narrow the search for a selective review of abstracts, retrieval of full articles, and grading of evidence according to systems used in established evidence-based models. Evidence-based best practice recommendations from the most recent literature on surgical methods and technologies, risks and benefits, outcomes, and surgeon qualifications and credentialing. We identified >135 articles; the 65 most relevant were reviewed in detail. Regular updates of evidence-based recommendations for best practices in WLS are required to address rapid changes in surgical techniques and patient demographics. Key factors in patient safety include surgical risk factors, type of procedure, surgeon training, and facility certification.Obesity (2009) 17 5, 863–870. doi:10.1038/oby.2008.570 [ABSTRACT FROM AUTHOR]

To update evidence-based best practice guidelines for coding and reimbursement and establish policy and access standards for weight loss surgery (WLS). Systematic search of English-language literature on WLS and health-care policy, access, insurance reimbursement, coding, private payers, public policy, and mandated benefits published between April 2004 and May 2007 in MEDLINE, EMBASE, and the Cochrane Library. Use of key words to narrow the search for a selective review of abstracts, retrieval of full articles, and grading of evidence according to systems used in established evidence-based models. We identified 51 publications in our literature search; the 20 most relevant were examined in detail. These included reviews, cost–benefit analyses, and trend and cost studies from administrative databases. Literature on policy issues surrounding WLS are very sparse and largely focused on economic analyses. Reports on policy initiatives in the public and private arenas are primarily limited to narrative reviews of nonsurgical efforts to fight obesity. A substantial body of work shows that WLS improves or reverses most obesity-related comorbidities. Mounting evidence also indicates that WLS confers a significant survival advantage for those who undergo it. WLS is a viable and cost-effective treatment for an increasingly common disease, and policy decisions are more frequently being linked to incentives for national health-care goals. However, access to WLS often varies by payer and region. Currently, there are no uniform criteria for determining patient appropriateness for surgery.Obesity (2009) 17 5, 918–923. doi:10.1038/oby.2008.573 [ABSTRACT FROM AUTHOR]

The objective of this study is to update evidence-based best practice guidelines for specialized facilities and resources for weight loss surgery (WLS). We performed systematic search of English-language literature on WLS and facilities, equipment, and resources published between April 2004 and May 2007 in PubMed, MEDLINE, and the Cochrane Library. Keywords were used to narrow the search for a selective review of abstracts, retrieval of full articles, and grading of evidence according to systems used in established evidence-based models. Evidence-based best practice recommendations from the most recent literature on specialized facilities and resources for WLS were developed. We identified 1,647 papers in our literature search; the 46 most relevant were reviewed in detail. Regular updates of evidence-based recommendations for best practices in facilities and resources for WLS are required to address technology advances and growing recognition of the need for adequate equipment and specially built nursing units. Key factors in patient safety include availability of trained personnel and specialized equipment for the care of extremely obese WLS patients.Obesity (2009) 17 5, 911–917. doi:10.1038/oby.2008.581 [ABSTRACT FROM AUTHOR]

The article focuses on a study that was conducted to find the relationship between dyspnea, pulmonary function test (PFT) results and respiratory derive in morbidly obese patients before and after weight loss. Dyspnea is a common complaint in obese patients, who also frequently suffer from the abnormal (PFT) results without any evidence of lung disease. It was found in the study that the degree of dyspnea commonly observed in obese patients can be explained in terms of the increased ventilatory drive as well as the reduced static lung volumes. It was also revealed in the study that gastroplasty results in significant reduction in body mass index and respiratory drive measurements. In addition, gastroplasty also results in a significant improvement in dyspnea.

Background: Little is known about the determinants of individual variability in body weight and fat loss after gastric bypass surgery or about the effects of massive weight loss induced by this surgery on energy requirements. Objectives: The objectives were to determine changes in energy expenditure and body composition with weight loss induced by gastric bypass surgery and to identify presurgery predictors of weight loss. Design: Thirty extremely obese women and men with a mean (±SD) age of 39.0 ± 9.6 y and a body mass index (BMI; in kg/m²) of 50.1 ± 9.3 were tested longitudinally under weight-stable conditions before surgery and after weight loss and stabilization (14±2 mo). Tdtal energy expenditure (TEE), resting energy expenditure (REE), body composition, and fasting leptin were measured. Results: Subjects lost 53.2 ± 22.2 kg body weight and had significant decreases in REE (-2.4 ± 1.0 MJ/d; P < 0.001) and TEE (-3.6 ± 2.5 MJ/d; P < 0.001). Changes in REE were predicted by changes in fat-free mass and fat mass. The average physical activity level (TEE/REE) was 1.61 at both baseline and follow-up (P = 0.98). Weight loss was predicted by baseline fat mass and BMI but not by any energy expenditure variable or leptin. Measured REE at follow-up was not significantly different from predicted REE. Conclusions: TEE and REE decreased by 25% on average after massive weight loss induced by gastric bypass surgery. REE changes were predicted by loss of body tissue; thus, there was no significant long-term change in energy efficiency that would independently promote weight regain. [ABSTRACT FROM AUTHOR]

FBody composition methods were examined in 20 women [body mass index (BMI) 48.7 ± 8.8 kg/m²] before and after weight loss [-44.8 ± 14.6 (SD) kg] after gastric bypass (GBP) surgery. The reference method, a three-compartment (3C) model using body density by air displacement plethysmography and total body water (TBW) by H[sub 2][sup 18]0 dilution (3C-H[sub 2][sup 18]O), showed a decrease in percent body fat (%BF) from 51.4 to 34.6%. Fat-free mass hydration was significantly higher than the reference value (0.738) in extreme obesity (0.756; P < 0.001) but not after weight reduction (0.747; P = 0.16). %BF by H[sub 2][sup 18]O dilution and air displacement plethysmography differed significantly from %BF by 3C-H[sub 2][sup 18]O in extreme obesity (P < 0.05) and 3C models using ²H[sub 2]O or bioelectrical impedance analysis (BIA) to determine TBW improved mean %BF estimates over most other methods at both time points. BIA results varied with the equation used, but BIA better predicted %BF than did BMI at both time points. All methods except BIA using the Segal equation were comparable to the reference method for determining changes over time. A simple 3C model utilizing air displacement plethysmography and BIA is useful for clinical evaluation in this population. [ABSTRACT FROM AUTHOR]

Surgical approaches to weight loss are a fairly recent phenomenon. We review the most common procedures and their peri- and past-operative complications. Surgeries include jejunoileal bypass, biliopancreatic diversion and variants, gastric bypass, and gastroplasty, as well as several laparoscopic procedures. [ABSTRACT FROM AUTHOR]