Changes in body composition with weight loss: obese subjects randomized to surgical and medical programs

Long-term effect of bariatric surgery on body composition in patients with morbid obesity: A systematic review and meta-analysis

We performed a meta-analysis to provide quantitative estimates of fat mass (FM) and fat-free mass (FFM) changes in patients following bariatric surgery over 1 year. A systematic search of PubMed, SCOPUS and Web of Science databases was conducted; the pooled weighted mean difference (WMD) and 95% confidence intervals (CI) were calculated using a random-effects model. Thirty-four studies including Roux en-Y gastric bypass (RYGB), sleeve gastrectomy (SG) biliopancreatic diversion (BPD) and gastric banding (GB) were analyzed. RYGB decreased in body FM (-28.99 kg [31.21, -26.77]) or FM% (-12.73% [-15.14, -10.32]) or FFM (-9.97 kg [-10.93, -9.03]), which were greater than SG and GB. Moreover, the FFM% in RYGB group (11.72% [7.33, 16.11]) was more than SG (5.7% [4.44, 6.95]) and GB (8.1% [6.15, 10.05]) groups. Bariatric surgeries, especially RYGB, might be effective for a decrease in FM and maintenance of FFM in patients with morbid obesity in over 1 year.

Weight Regain After Gastric Plication: Reoperative Sleeve Gastrectomy or Roux-en-Y Gastric Bypass?-Analysis of 116 Consecutive Cases

PURPOSE

In France, laparoscopic gastric plication (GP) has rarely been utilized as a weight loss procedure. Although relatively safe and efficient, its long-term results are still controversial. The goal of this study is to assess the indications and outcomes of revisional surgery post-GP.

MATERIALS AND METHODS

Between February 2010 and September 2017, patient characteristics undergoing GP were prospectively collected from our database. Failure of conservative treatment or presence of anatomical anomaly explaining weight loss insufficiency was an indication for revisional surgery (RS).

RESULTS

A total of 300 patients were included, 41 patients were lost to follow-up (13.7%), 124 patients (41.3%) had total weight loss (TWL) > 30%, and 116 patients (38.7%) underwent RS. Revisional procedures were laparoscopic Roux-en-Y gastric bypass (RYGB) in 72 patients (62.1%) and sleeve gastrectomy (SG) in 44 patients (37.9%). The median interval to RS was 29 months. The mean operative time was 60 min for the SG and 125 min for the RYGB (p < 0.0001). Mortality was nil. Significant morbidity occurred in eight patients (6.9%) including 4 non-abdominal complications, 1 gastric leak, 1 case of hemorrhage, 1 case of hematoma, and 1 intra-abdominal abscess. The mean length of hospital stay (LOS) was 2.9 days (range, 1-11) for the SG group vs 3.2 days (range, 2-8) for the RYGB group (p = 0.608).

CONCLUSION

GP is associated with a relatively high rate of weight regain or insufficient weight loss. When compared to SG, RYGB seems to be the safer revisional procedure with fewer surgical complications.

Association of Bariatric Surgery With Risk of Fracture in Patients With Severe Obesity

IMPORTANCE

Given the complex relationship between body mass index, body composition, and bone density and the correlative nature of the studies that have established the prevailing notion that higher body mass indices may be protective against osteopenia and osteoporosis and, therefore, fracture, the absolute risk of fracture in patients with severe obesity who undergo either Roux-en-Y gastric bypass (RYGB) or sleeve gastrectomy (SG) compared with those who do not undergo bariatric surgery is unknown.

OBJECTIVE

To assess the rates of fractures associated with obesity and compare rates between those who do not undergo bariatric surgery, those who undergo RYGB, and those who undergo SG.

DESIGN, SETTING, AND PARTICIPANTS

In this retrospective multicenter cohort study of Medicare Standard Analytic Files derived from Medicare parts A and B records from January 2004 to December 2014, patients classified as eligible for bariatric surgery using the US Centers of Medicare & Medicaid criteria who either did not undergo bariatric surgery or underwent RYGB or SG were exactly matched in a 1:1 fashion based on their age, sex, Elixhauser Comorbidity Index, hypertension, smoking status, nonalcoholic fatty liver disease, hyperlipidemia, type 2 diabetes, osteoporosis, osteoarthritis, and obstructive sleep apnea status. Data were analyzed from November to December 2019.

EXPOSURES

RYGB or SG.

MAIN OUTCOMES AND MEASURES

The primary outcome measured in this study was the odds of fracture overall based on exposure to bariatric surgery. Secondary outcomes included the odds of type of fracture (humerus, radius or ulna, pelvis, hip, vertebrae, and total fractures) based on exposure to bariatric surgery.

RESULTS

A total of 49 113 patients were included and were equally made up of 16 371 bariatric surgery-eligible patients who did not undergo weight loss surgery, 16 371 patients who had undergone RYGB, and 16 371 patients who had undergone SG. Each group consisted of an equal number of 4109 men (25.1%) and 12 262 women (74.9%) and had an equal distribution of ages, with 11 780 patients (72.0%) 64 years or younger, 4230 (25.8%) aged 65 to 69 years, 346 (2.1%) aged 70 to 74 years, and 15 (0.1%) aged 75 to 79 years. Patients undergoing RYGB were found to have no significant difference in odds of fractures compared with bariatric surgery-eligible patients who did not undergo surgery. Patients undergoing undergone SG were found to have decreased odds of fractures of the humerus (odds ratio [OR], 0.57; 95% CI, 0.45-0.73), radius or ulna (OR, 0.38; 95% CI, 0.25-0.58), hip (OR, 0.49; 95% CI, 0.33-0.74), pelvis (OR, 0.34; 95% CI, 0.18-0.64), vertebrae (OR, 0.60; 95% CI, 0.48-0.74), or fractures in general (OR, 0.53; 95% CI, 0.46-0.62). Compared with patients undergoing SG, patients undergoing RYGB had a significantly greater risk of total fractures (OR, 1.79; 95% CI, 1.55-2.06) and humeral fractures (OR, 1.60; 95% CI, 1.24-2.07).

CONCLUSIONS AND RELEVANCE

In this cohort study, bariatric surgery was associated with a reduced risk of fracture in bariatric surgery-eligible patients. Sleeve gastrectomy might be the best option for weight loss in patients in which fractures could be a concern, as RYGB may be associated with an increased fracture risk compared with SG.

Effects of Roux-en-Y Gastric Bypass on Osteoclast Activity and Bone Density in Morbidly Obese Patients with Type 2 Diabetes

INTRODUCTION

Roux-en-Y gastric bypass (RYGB) is a well-established treatment for morbid obesity and type 2 diabetes. The effects of RYGB on bone metabolism and bone health are largely unknown.

OBJECTIVE

Determine the changes in osteoclast function and bone density 1 year after RYGB as compared with a control group undergoing a diabetes support and education program (DSE).

DESIGN

A prospective cohort study with patients matched for weight and age assigned to RYGB or DSE.

SETTING

Large academic institution.

PATIENTS OR OTHER PARTICIPANTS

Patients with type 2 diabetes mellitus and morbid obesity (body mass index greater than 35 kg/m2).

INTERVENTION

Subjects either received laparoscopic RYBG or DSE, which consisted of nutritional, exercise, and dietary counseling performed by a certified diabetic educator and a nutritionist three times over a year.

MAIN OUTCOME MEASURE

Osteoclast activity, bone mineral density.

RESULTS

One year after, intervention subjects undergoing RYGB have a 280% increase in osteoclast activity as compared with a 7.6% increase in the DSE control group (P < 0.001). Furthermore, there was a statistically significant increase in sclerostin levels in subjects undergoing RYGB compared with an increase in the control group. The total bone mineral density was statistically unchanged within 1 year of intervention in both groups. A statistically significant decrease in bone mineral density in the left ribs (decrease of 6.8%, P < 0.05) and lumbar spine (decrease of 4.0%, P < 0.05) was seen 1 year after RYGB.

CONCLUSIONS

There is a significant increase in osteoclast activity observed 1 year after RYGB; the long-term clinical implications of this increased bone metabolism are unknown.

Comparative Effects of Medical Versus Surgical Weight Loss on Body Composition: a Pilot Randomized Trial

OBJECTIVE

Bariatric surgery leads to more rapid and greater weight loss (WL) compared to medical weight loss (MWL), but the differences in body composition (BC) changes for these modalities remain unclear. Due to the known health risks associated with central adiposity, we compared the changes in regional distribution of fat mass (FM) and lean mass (LM) after surgical versus MWL.

METHODS

In this 1:1:1 randomized trial among 15 persons with type 2 diabetes and body mass index (BMI) 30-39.9 kg/m², we compared changes in BC, by dual-energy X-ray absorptiometry and abdominal computerized tomography, at time of 10%WL or 9 months after intervention (whichever came first). Participants underwent MWL, adjustable gastric banding (AGB), or Roux-en-Y gastric bypass (RYGB). Non-parametric tests evaluated BC differences (FM, LM, and visceral adipose tissue [VAT]) within and across all three arms and between pair-wise comparisons.

RESULTS

Twelve female participants (75% African American) completed the study. Patient age, BMI, and baseline anthropometric characteristics were similar across study arms. AGB lost more LM (MWL - 5.2%, AGB - 10.3%, p = 0.021) and VAT (MWL + 10.9%, AGB - 28.0%, p = 0.049) than MWL. RYGB tended to lose more VAT (MWL +10.9%, RYGB - 20.2%, p = 0.077) than MWL. AGB tended to lose more LM than RYGB (AGB - 12.38%, RYGB - 7.29%, p = 0.15).

CONCLUSIONS

At similar WL, AGB lost more LM and VAT than MWL; RYGB similarly lost more VAT. Given the metabolic benefits of reducing VAT and retaining LM, larger studies should confirm the changes in BC after surgical versus medical WL.

CLINICAL TRIAL REGISTRATION

NCTDK089557 - ClinicalTrials.gov.

Metabolic and Endocrine Consequences of Bariatric Surgery

Obesity is one of the most serious worldwide epidemics of the twenty-first century according to the World Health Organization. Frequently associated with a number of comorbidities, obesity threatens and compromises individual health and quality of life. Bariatric surgery (BS) has been demonstrated to be an effective treatment to achieve not only sustained weight loss but also significant metabolic improvement that goes beyond mere weight loss. The beneficial effects of BS on metabolic traits are so widely recognized that some authors have proposed BS as metabolic surgery that could be prescribed even for moderate obesity. However, most of the BS procedures imply malabsorption and/or gastric acid reduction which lead to nutrient deficiency and, consequently, further complications could be developed in the long term. In fact, BS not only affects metabolic homeostasis but also has pronounced effects on endocrine systems other than those exclusively involved in metabolic function. The somatotropic, corticotropic, and gonadal axes as well as bone health have also been shown to be affected by the various BS procedures. Accordingly, further consequences and complications of BS in the long term in systems other than metabolic system need to be addressed in large cohorts, taking into account each bariatric procedure before making generalized recommendations for BS. In this review, current data regarding these issues are summarized, paying special attention to the somatotropic, corticotropic, gonadal axes, and bone post-operative health.

Bone Health After Bariatric Surgery

Bariatric surgery results in long-term weight loss and improvement or resolution in obesity-related comorbidities. However, mounting evidence indicates that it adversely affects bone health. This review summarizes clinical research findings about the impact of bariatric surgery on skeletal outcomes. The literature is the largest and strongest for the Roux-en-Y gastric bypass (RYGB) procedure, as RYGB was the most commonly performed bariatric procedure worldwide until it was very recently overtaken by the sleeve gastrectomy (SG). Because SG is a newer procedure, its skeletal effects have not yet been well defined. Epidemiologic studies have now demonstrated an increased risk of fracture after RYGB and biliopancreatic diversion with duodenal switch, both of which include a malabsorptive component. As these epidemiologic data have emerged, patient-oriented studies have elucidated the bone tissue-level changes that may account for the heightened skeletal fragility. Bariatric surgery induces early and dramatic increases in biochemical markers of bone turnover. A notable feature of recent patient-oriented clinical studies is the application of advanced skeletal imaging modalities; studies address the limitations of dual-energy X-ray absorptiometry (DXA) by using quantitative computed tomography (QCT)-based modalities to examine volumetric bone mineral density and compartment-specific density and microstructure. RYGB results in pronounced declines in bone mass at the axial skeleton demonstrated by DXA and QCT, as well as at the appendicular skeleton demonstrated by high-resolution peripheral quantitative computed tomography (HR-pQCT). RYGB has detrimental effects on trabecular and cortical microarchitecture and estimated bone strength. Skeletal changes after RYGB appear early and continue even after weight loss plateaus and weight stabilizes. The skeletal effects of bariatric surgery are presumably multifactorial, and mechanisms may involve nutritional factors, mechanical unloading, hormonal factors, and changes in body composition and bone marrow fat. Clinical guidelines address bone health and may mitigate the negative skeletal effects of surgery, although more research is needed to direct and support such guidelines. © 2018 The Authors. JBMR Plus is published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research.

Five-Year Outcomes: Laparoscopic Greater Curvature Plication for Treatment of Morbid Obesity

BACKGROUND

Laparoscopic greater curvature plication (LGCP) is a newer metabolic/bariatric surgical procedure that requires no resection, bypass, or implantable device. We report outcomes in a cohort of LGCP patients at 5-year follow-up.

METHODS

Body mass index (BMI, kg/m²) evolution, excess weight loss (%EWL), excess BMI loss (%EBMIL), and total weight loss (%TWL) were recorded. Repeated measures analysis of variance (ANOVA) was used to assess BMI change over 5 years. Two-step cluster analysis was used to profile LGCP patients according to significant characteristics relative to successful 5-year weight loss.

RESULTS

Of patients entering the study between 2010 and 2011 with complete weight data through 5-year follow-up (86.9%, 212/244), mean age was 45.8 ± 10.9 years; mean baseline BMI, 41.4 ± 5.5 (81.6% women); 58 patients (27.4%) had type 2 diabetes. Mean operative time was 69.0 min; mean hospitalization, 38 h (24-72). ANOVA indicated a significant BMI reduction out to 2 years (p < 0.001), a plateau at 3 and 4 years, and a moderate but significant BMI increase at 5 years (p < 0.01). EBMIL at 1, 2, 3, 4, and 5 years was as follows: 50.7 ± 9.1%, 61.5 ± 8.1%, 60.2 ± 7.0%, 58.5 ± 7.0%, and 56.8 ± 6.3%. At 5 years, 79.2% (168/212) of patients were successful; 20.8% (44/212) experienced a suboptimal weight outcome; mean weight regain, 9.2%. Cluster analysis identified four distinct LGCP patient profiles. Diabetes improvement rate was 65.5%. There were 12 reoperations (4.9%): 4 emergency (1.6%) and 8 (3.3%) elective. There was no mortality.

CONCLUSIONS

At 5-year follow-up, LGCP proved to be safe and effective, with 56.8% EBMIL and a low rate of complications.

Poor Physical Function as a Marker of Sarcopenia in Adults with Class II/III Obesity

BACKGROUND

Adults with class II/III obesity [body mass index (in kg/m2) ≥35] may present with a phenotype characterized by low lean mass and excess fat mass, a condition known as sarcopenic obesity (SO). Little is known about the prevalence and relevance of SO in these individuals, primarily due to a lack of relevant diagnostic criteria.

OBJECTIVE

Here, we explored the definition of SO based on physical function as an outcome of interest in adults with class II/III obesity and applied this definition to compare clinical characteristics between SO and non-SO patients.

METHODS

In this cross-sectional analysis, patients' demographic, anthropometric, and biochemical characteristics, as well as comorbidities and physical activity levels, were collected at an obesity specialty clinic prior to any treatment. Body composition was assessed by dual-energy X-ray absorptiometry. Physical function was assessed by self-reported difficulties with activities of daily living (ADLs) from an 11-item questionnaire. Five SO definitions were tested against reported difficulty with ADLs with the use of receiver operating characteristic (ROC) analysis.

RESULTS

A total of 120 subjects (86% women) aged 46 ± 11 y were included. Based on ROC analysis, SO was best defined by an appendicular skeletal mass (ASM)/weight x 100 (%) <19.35% for women and <24.33% for men, resulting in a prevalence of 25% (n = 30, women 22.3%, men 41.2%). SO was significantly associated with older age, higher waist circumference, higher triglycerides, greater use of antihypertensive medications, and lower physical activity.

CONCLUSIONS

In this sample of adults with class II/III obesity, difficulties with ADLs were best associated with measures of ASM in relation to total body weight. Patients identified with SO using this criterion presented with poorer clinical outcomes such as factors of elevated cardiometabolic risk.

Anthropometric Assessment for Bariatric Procedures in the Private Practice of a Registered Dietitian in Colombia

BACKGROUND

Obesity and its consequences have now reached worldwide pandemic proportions. Among treatments, bariatric interventions are the most effective for weight reduction. Here, we describe the change in anthropometric measurements (AMs) of 615 adult bariatric procedure patients seen in the private practice of a registered dietitian (RD) in Bogotá, Colombia.

METHODS

Observational retrospective study of AMs recorded between 1996 and 2013 for patients who had laparoscopic sleeve gastrectomy (LSG, n = 290), laparoscopic adjustable gastric banding (LAGB, n = 207), and laparoscopic Roux-EN-Y gastric bypass (LRYGB, n = 36) or the non-surgical gastric balloon (GB, n = 82) procedure. Patients had three bimonthly follow-up visits. Paired t tests compared baseline (first) and 6-month (fourth) follow-up visit values.

RESULTS

Differences in AMs between the baseline and fourth visits were statistically significant for the surgical interventions. A mean weight loss of 22 kg, equivalent to a 22% total body weight loss, together with significant reduction of the waist-to-height-ratio (WHtR)(p < 0.001) and body mass index (BMI)(p < 0.001), was observed across all procedures.

CONCLUSIONS

The use of multiple AMs enables a comprehensive assessment of body composition in patients who undergo bariatric procedures. Our study is a useful resource for international future reference and highlights the impact that the RD can have on understanding and influencing the effectiveness of bariatric procedures.

DXA-assessed changes in body composition in obese women following two different weight loss programs

OBJECTIVE

Changes in body composition during weight loss programs might have a significant effect on long-term results. The aim of this study was to test these changes by dual energy x-ray absorptiometry (DXA) in obese women enrolled into two different weight loss medical programs.

METHODS

We prospectively studied 71 women assigned to either an intensive 3-mo cognitive-behavioral therapy (CBT) or a 1-mo nutritional counseling plan (NCP). All patients underwent DXA whole-body scan before treatment and after 3, 6, and 12 mo. Fat mass (FM), non-bone lean mass (LM) and bone mineral content were assessed at whole-body and regional levels. Android visceral adipose tissue (VAT) also was estimated.

RESULTS

Twenty-three patients missed one or more follow-up controls and were excluded from the final analysis. Twenty-seven patients (body mass index [BMI] 41.9 ± 6.7 kg/m²) remained in the CBT group and 21 (BMI 33.4 ± 4 kg/m²) in the NCP group. The progressive decrease of BMI in both groups was associated with reduced whole-body and regional FM, which was more marked in CBT. During follow-up, a progressive decrease of total FM-to-LM and android FM-to-LM ratios were observed both in CBT (Δ12-mo versus baseline -7.8 ± 9.6% and -9.5 ± 12.7%, respectively; P < 0.01) and NCP (Δ12-mo versus baseline -5.9 ± 9.6% and -7 ± 13.4%, respectively; P < 0.05). VAT was the parameter showing the largest decrease (-14.2 ± 17.4% and -11.3 ± 18.2% at 12 mo, respectively in CBT and NCP; P < 0.05).

CONCLUSIONS

Lifestyle-induced weight loss is associated with selective changes in body composition parameters, regardless of initial BMI and treatment program, limiting sarcopenic obesity. DXA may quantify the metabolically healthier redistribution of total and regional FM and VAT.

The Effects of Bariatric Surgery on Bone Metabolism

Most metabolic effects following bariatric surgery are favorable. One area in which the consequences seem to be detrimental is on skeletal health. Mechanisms that have been cited include malabsorption of calcium and vitamin D, decrease in mechanical loading, and changes in gastrointestinal and fat-derived hormone levels. It is important that the impact of these procedures on bone metabolism is closely examined. The significance of the bone loss that occurs, and its possible effect on future fracture risk, should also be evaluated.

Relationships among fat mass, fat-free mass and height in adults: A new method of statistical analysis applied to NHANES data

OBJECTIVES

The positive influence of fat mass (FM) on fat-free mass (FFM) has been quantified previously by various methods involving regression analysis of population data, but some are fundamentally flawed through neglect of the tendency of taller individuals to carry more fat. Differences in FFM due to differences in FM-and not directly related to differences in height-are expressed as ΔFFM/ΔFM, denoted K_F . The main aims were to find a sounder regression-based method of quantifying K_F and simultaneously of estimating mean BMI₀ , the BMI of hypothetical fat-free individuals. Other, related, objectives were to check the linearity of FFM-FM relationships and to quantify the correlation between FM and height.

METHODS

New statistical methods, explored and verified by Monte Carlo simulation, were applied to NHANES data. Regression of height² on FFM and FM produced estimates of mean K_F and indirectly of BMI₀ . Both were then adjusted to allow for variability in K_F around its mean. Its standard deviation was estimated by a novel method.

RESULTS

Relationships between FFM and FM were linear, not semilogarithmic as is sometimes assumed. Mean K_F is similar in Mexican American men and women, but higher in men than women in non-Hispanic European Americans and African Americans. Mean BMI₀ is higher in men than in women. FM correlates more strongly with height than has been found previously.

CONCLUSIONS

A more accurate way of quantifying mean BMI₀ and the dependence of FFM on FM is established that may be easily applied to new and existing population data.

Depo-Provera (depot medroxyprogesterone acetate) use after bariatric surgery

In the US, obesity rates are increasing greatly. The Centers for Disease Control and Prevention estimates that 68.5% of Americans, including 63.9% of adult women older than 20 years, are overweight (body mass index between 25 kg/m² and 29.9 kg/m²) or obese (body mass index >30 kg/m²). In light of this, it is not surprising that the rates of bariatric surgery have also been increasing. When considering the metabolic changes associated with both bariatric surgery and contraceptive use, in combination with the unique medical considerations of obese women, it is indisputable that clear guidelines are needed when counseling obese patients of reproductive age after bariatric surgery. In this literature review, we focus on depot medroxyprogesterone acetate (DMPA) and the implications of its use in obese women, preweight and postweight loss following bariatric surgery. Both DMPA use and bariatric surgery are known to cause bone loss, but it is still unclear whether there is an additive effect of the two factors on bone loss and whether either of these factors directly leads to an increased risk of bone fracture. The current consensus guidelines do not impose a restriction on the use of DMPA after bariatric surgery. DMPA use is associated with weight gain, and it is unclear whether weight loss blunting occurs with the use of DMPA after bariatric surgery. Prior studies had demonstrated an association with weight gain in adolescents, and therefore, those prescribing DMPA use after bariatric surgery in adolescents should proceed with caution. Adult women do not have a similar response to the use of DMPA. DMPA use has rarely been associated with increased risk of venous thromboembolism (VTE). The obesity-associated increase in VTE should be mitigated by surgically induced weight loss. The concurrent use of DMPA in the post bariatric surgical period should not further increase the risk of VTE.

Effects of Gastric Bypass and Gastric Banding on Bone Remodeling in Obese Patients With Type 2 Diabetes

CONTEXT

Roux-en-Y gastric bypass (RYGB) leads to high-turnover bone loss, but little is known about skeletal effects of laparoscopic adjustable gastric banding (LAGB) or mechanisms underlying bone loss after bariatric surgery.

OBJECTIVE

To evaluate effects of RYGB and LAGB on fasting and postprandial indices of bone remodeling.

DESIGN AND SETTING

Ancillary investigation of a prospective study at 2 academic institutions.

PARTICIPANTS

Obese adults aged 21-65 years with type 2 diabetes who underwent RYGB (n = 11) or LAGB (n = 8).

OUTCOMES

Serum C-terminal telopeptide (CTX), procollagen type 1 N-terminal propeptide (P1NP), and PTH were measured during a mixed meal tolerance test at baseline, 10 days and 1 year after surgery. Changes in 25-hydroxyvitamin D, polypeptide YY (PYY), glucagon-like peptide-1, glucose-dependent insulinotropic peptide, and insulin were also assessed.

RESULTS

Fasting CTX increased 10 days after RYGB but not LAGB (+69 ± 23% vs +12±12%, P < .001), despite comparable weight loss at that time. By 1 year, fasting CTX and P1NP increased more after RYGB than LAGB (CTX +221 ± 60% vs +15 ± 6%, P<0.001; P1NP +93 ± 25% vs -9 ± 10%, P < .001) and weight loss was greater with RYGB. Changes in CTX were independent of PTH and 25-hydroxyvitamin D but were associated with increases in fasting PYY. Postprandial suppression of CTX was more pronounced after RYGB than LAGB at 10 days and 1 year postoperatively.

CONCLUSIONS

RYGB is accompanied by early increases in fasting indices of bone remodeling, independent of weight loss or changes in PTH or 25-hydroxyvitamin D. LAGB did not affect bone markers. PYY and other enterohormonal signals may play a role in RYGB-specific skeletal changes.

Visceral fat and body composition changes in a female population after RYGBP: a two-year follow-up by DXA

BACKGROUND

Our aim was to monitor the impact of Roux-en-Y gastric bypass (RYGBP) on body composition over a 24-month period by dual-energy X-ray absorptiometry (DXA).

METHODS

Forty-one women (40.6 ± 10.0 years old; 42.6 ± 6.6 kg/m(2)) entering a bariatric surgery programme were submitted to whole-body DXA (Lunar iDXA) before treatment and after 3, 6, 12 and 24 months. Fat mass (FM), non-bone lean mass (LM), bone mineral content (BMC) and density (BMD) were measured at whole body and regionally. Android visceral adipose tissue (VAT) was estimated by a recently validated software.

RESULTS

Twenty-nine patients (44.3 ± 11.8 years old; BMI, 45.4 ± 8.9 kg/m(2)) concluded the study. Following surgery, the progressive decrease of BMI was associated with reduced whole-body and regional FM. LM showed a moderate decrease at 3 months and stabilized thereafter. A progressive decrease of total FM/LM and android FM/LM ratios were observed in the 3- to 6-month (-19.1 ± 8.4 % and -26.5 ± 10.9 %, respectively; p < 0.0001) and 6- to 12-month periods (-23.5 ± 16.8 % and -29.4 ± 23.9 %, respectively; p < 0.0001). VAT was the parameter showing the largest decrease (-65.6 ± 17.5 % at 12 months; p < 0.0001). Two years after the surgery, a slight but significant decrease of total and regional LM was observed, without any significant change in BMI.

CONCLUSIONS

Body composition significantly changes after RYGBP with a metabolically healthier redistribution of total and regional FM and a positive balance of FM/LM variation. DXA should be considered as a valid supplementary tool for the clinical assessment and follow-up in patients undergoing bariatric surgery.

The efficacy of Bioelectrical Impedance Analysis (BIA) in monitoring body composition changes during treatment of restrictive eating disorder patients

REVIEWS

Treating restrictive eating disorder patients is metabolically and psychologically complex. Determining body composition is an important diagnostic and treatment option for these patients, because it ascertains whether the acquisition of body mass during refeeding is metabolically appropriate - ideally an approximate 20/80% - 25/75% fat/lean body mass ratio. The purpose of this paper is to evaluate the efficacy of Bioelectrical Impedance Analysis (BIA) during the treatment period of patients with restrictive eating disorders. The search engines PubMed, Medline, and MSN were utilized using combinations of key words, "Bioimpedance Analysis", "body composition determination", "eating disorders", and "anorexia".

CONCLUSIONS

The literature indicates that the use of Bioelectrical Impedance Analysis (BIA) in eating disorder patients to be efficacious in determining body composition during the treatment period, and that only assessing weight changes does not necessarily reflect specific changes in various body compartments. Also, utilizing BIA has the advantage of using each patient as his/her own "control", potentially allowing for a more individualized nutrition regimen according to the body composition changes observed during treatment.

Surgery for weight loss in adults

BACKGROUND

Bariatric (weight loss) surgery for obesity is considered when other treatments have failed. The effects of the available bariatric procedures compared with medical management and with each other are uncertain. This is an update of a Cochrane review first published in 2003 and most recently updated in 2009.

OBJECTIVES

To assess the effects of bariatric surgery for overweight and obesity, including the control of comorbidities.

SEARCH METHODS

Studies were obtained from searches of numerous databases, supplemented with searches of reference lists and consultation with experts in obesity research. Date of last search was November 2013.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing surgical interventions with non-surgical management of obesity or overweight or comparing different surgical procedures.

DATA COLLECTION AND ANALYSIS

Data were extracted by one review author and checked by a second review author. Two review authors independently assessed risk of bias and evaluated overall study quality utilising the GRADE instrument.

MAIN RESULTS

Twenty-two trials with 1798 participants were included; sample sizes ranged from 15 to 250. Most studies followed participants for 12, 24 or 36 months; the longest follow-up was 10 years. The risk of bias across all domains of most trials was uncertain; just one was judged to have adequate allocation concealment.All seven RCTs comparing surgery with non-surgical interventions found benefits of surgery on measures of weight change at one to two years follow-up. Improvements for some aspects of health-related quality of life (QoL) (two RCTs) and diabetes (five RCTs) were also found. The overall quality of the evidence was moderate. Five studies reported data on mortality, no deaths occurred. Serious adverse events (SAEs) were reported in four studies and ranged from 0% to 37% in the surgery groups and 0% to 25% in the no surgery groups. Between 2% and 13% of participants required reoperations in the five studies that reported these data.Three RCTs found that laparoscopic Roux-en-Y gastric bypass (L)(RYGB) achieved significantly greater weight loss and body mass index (BMI) reduction up to five years after surgery compared with laparoscopic adjustable gastric banding (LAGB). Mean end-of-study BMI was lower following LRYGB compared with LAGB: mean difference (MD) -5.2 kg/m² (95% confidence interval (CI) -6.4 to -4.0; P < 0.00001; 265 participants; 3 trials; moderate quality evidence). Evidence for QoL and comorbidities was very low quality. The LRGYB procedure resulted in greater duration of hospitalisation in two RCTs (4/3.1 versus 2/1.5 days) and a greater number of late major complications (26.1% versus 11.6%) in one RCT. In one RCT the LAGB required high rates of reoperation for band removal (9 patients, 40.9%).Open RYGB, LRYGB and laparoscopic sleeve gastrectomy (LSG) led to losses of weight and/or BMI but there was no consistent picture as to which procedure was better or worse in the seven included trials. MD was -0.2 kg/m² (95% CI -1.8 to 1.3); 353 participants; 6 trials; low quality evidence) in favour of LRYGB.  No statistically significant differences in QoL were found (one RCT). Six RCTs reported mortality; one death occurred following LRYGB. SAEs were reported by one RCT and were higher in the LRYGB group (4.5%) than the LSG group (0.9%). Reoperations ranged from 6.7% to 24% in the LRYGB group and 3.3% to 34% in the LSG group. Effects on comorbidities, complications and additional surgical procedures were neutral, except gastro-oesophageal reflux disease improved following LRYGB (one RCT). One RCT of people with a BMI 25 to 35 and type 2 diabetes found laparoscopic mini-gastric bypass resulted in greater weight loss and improvement of diabetes compared with LSG, and had similar levels of complications.Two RCTs found that biliopancreatic diversion with duodenal switch (BDDS) resulted in greater weight loss than RYGB in morbidly obese patients. End-of-study mean BMI loss was greater following BDDS: MD -7.3 kg/m² (95% CI -9.3 to -5.4); P < 0.00001; 107 participants; 2 trials; moderate quality evidence). QoL was similar on most domains. In one study between 82% to 100% of participants with diabetes had a HbA1c of less than 5% three years after surgery. Reoperations were higher in the BDDS group (16.1% to 27.6%) than the LRYGB group (4.3% to 8.3%). One death occurred in the BDDS group.One RCT comparing laparoscopic duodenojejunal bypass with sleeve gastrectomy versus LRYGB found BMI, excess weight loss, and rates of remission of diabetes and hypertension were similar at 12 months follow-up (very low quality evidence). QoL, SAEs and reoperation rates were not reported. No deaths occurred in either group.One RCT comparing laparoscopic isolated sleeve gastrectomy (LISG) versus LAGB found greater improvement in weight-loss outcomes following LISG at three years follow-up (very low quality evidence). QoL, mortality and SAEs were not reported. Reoperations occurred in 20% of the LAGB group and in 10% of the LISG group.One RCT (unpublished) comparing laparoscopic gastric imbrication with LSG found no statistically significant difference in weight loss between groups (very low quality evidence).  QoL and comorbidities were not reported. No deaths occurred. Two participants in the gastric imbrication group required reoperation.

AUTHORS' CONCLUSIONS

Surgery results in greater improvement in weight loss outcomes and weight associated comorbidities compared with non-surgical interventions, regardless of the type of procedures used. When compared with each other, certain procedures resulted in greater weight loss and improvements in comorbidities than others. Outcomes were similar between RYGB and sleeve gastrectomy, and both of these procedures had better outcomes than adjustable gastric banding. For people with very high BMI, biliopancreatic diversion with duodenal switch resulted in greater weight loss than RYGB. Duodenojejunal bypass with sleeve gastrectomy and laparoscopic RYGB had similar outcomes, however this is based on one small trial. Isolated sleeve gastrectomy led to better weight-loss outcomes than adjustable gastric banding after three years follow-up. This was based on one trial only.  Weight-related outcomes were similar between laparoscopic gastric imbrication and laparoscopic sleeve gastrectomy in one trial. Across all studies adverse event rates and reoperation rates were generally poorly reported. Most trials followed participants for only one or two years, therefore the long-term effects of surgery remain unclear.

Laparoscopic sleeve gastrectomy compared to a multidisciplinary weight loss program for obesity--effects on body composition and protein status

BACKGROUND

Optimal obesity therapy is a matter of debate. Besides weight reduction, other criteria such as safety and nutritional status are of relevance. Therefore, we compared a favored surgical intervention with the most effective conservative treatment regarding anthropometry and nutritional status.

METHODS

Fifty-four obese patients were included who underwent laparoscopic sleeve gastrectomy (LSG, n = 27) or a 52-week multidisciplinary intervention program (MIP, n = 27) for weight loss. Body weight, body composition assessed by bioelectrical impedance analysis, and serum protein levels were measured before and within 12 months after intervention.

RESULTS

After 1 year of observation, excess weight loss was more pronounced following LSG (65 %) compared to MIP (38 %, p < 0.001). In both groups, body fat was clearly reduced, but a higher reduction occurred in the LSG group. However, protein status deteriorated particularly in the LSG group. Within 1 year, body cell mass declined from 37.1 to 26.9 kg in the LSG group, but only from 35.7 to 32.2 kg in the MIP group. This resulted in an increased mean extracellular mass/body cell mass ratio (1.42 versus 1.00, p < 0.001), in a decreased mean phase angle (4.4° versus 6.6°, p < 0.001), and in a lower prealbumin level in serum (p < 0.02) in the LSG group compared to the MIP group.

CONCLUSIONS

LSG, compared to MIP, was more effective regarding excess weight loss and body fat loss within 1 year, however, induced more pronounced muscle mass and protein loss, possibly requiring particular interventions such as exercise or protein supplements.

Bone metabolism after bariatric surgery

Bariatric surgery is a popular and effective treatment for severe obesity but may have negative effects on the skeleton. This review summarizes changes in bone density and bone metabolism from animal and clinical studies of bariatric surgery, with specific attention to Roux-en-Y gastric bypass (RYGB), adjustable gastric banding (AGB), and sleeve gastrectomy (SG). Skeletal imaging artifacts from obesity and weight loss are also considered. Despite challenges in bone density imaging, the preponderance of evidence suggests that bariatric surgery procedures have negative skeletal effects that persist beyond the first year of surgery, and that these effects vary by surgical type. The long-term clinical implications and current clinical recommendations are presented. Further study is required to determine mechanisms of bone loss after bariatric surgery. Although early studies focused on calcium/vitamin D metabolism and mechanical unloading of the skeleton, it seems likely that surgically induced changes in the hormonal and metabolic profile may be responsible for the skeletal phenotypes observed after bariatric surgery.

Early experience with the Incisionless Operating Platform™ (IOP) for the treatment of obesity : the Primary Obesity Surgery Endolumenal (POSE) procedure

BACKGROUND

We report our initial experience and 6-month outcomes in a single center using the per-oral Incisionless Operating Platform™ (IOP) (USGI Medical) to place transmural plications in the gastric fundus and distal body using specialized suture anchors (the Primary Obesity Surgery Endolumenal [POSE] procedure).

METHODS

A prospective observational study was undertaken with institutional Ethics Board approval in a private hospital in Barcelona, Spain. Indicated patients were WHO obesity class I-II, or III, where patients refused a surgical approach.

RESULTS

Between February 28, 2011 and March 23, 2012, the POSE procedure was successfully performed in 45 patients: 75.6 % female; mean age 43.4 ± 9.2 SD (range 21.0-64.0). At baseline: mean absolute weight (AW, kg), 100.8 ± 12.9 (75.5-132.5); body mass index (BMI, kg/m(2)), 36.7 ± 3.8 (28.1-46.6). A mean 8.2 suture-anchor plications were placed in the fundus, 3.0 along the distal body wall. Mean operative time, 69.2 ± 26.6 min (32.0-126.0); patients were discharged in <24 h. Six-month mean AW was 87.0 ± 10.3 (68.0-111.5); BMI decreased 5.8 to 31.3 ± 3.3 (25.1-38.6) (p < 0.001); EWL was 49.4 %; TBWL, 15.5 %. No mortality or operative morbidity. Minor postoperative side effects resolved with treatment by discharge. Patients reported less hunger and earlier satiety post procedure. Liquid intake began 12 h post procedure with full solids by 6 weeks.

CONCLUSIONS

At 6-month follow-up of a prospective case series, the POSE procedure appeared to provide safe and effective weight loss without the scarring, pain, and recovery issues of open and laparoscopic bariatric surgery. Long-term follow-up and further study are required.

Early experience with the Incisionless Operating Platform™ (IOP) for the treatment of obesity : the Primary Obesity Surgery Endolumenal (POSE) procedure

BACKGROUND

We report our initial experience and 6-month outcomes in a single center using the per-oral Incisionless Operating Platform™ (IOP) (USGI Medical) to place transmural plications in the gastric fundus and distal body using specialized suture anchors (the Primary Obesity Surgery Endolumenal [POSE] procedure).

METHODS

A prospective observational study was undertaken with institutional Ethics Board approval in a private hospital in Barcelona, Spain. Indicated patients were WHO obesity class I-II, or III, where patients refused a surgical approach.

RESULTS

Between February 28, 2011 and March 23, 2012, the POSE procedure was successfully performed in 45 patients: 75.6 % female; mean age 43.4 ± 9.2 SD (range 21.0-64.0). At baseline: mean absolute weight (AW, kg), 100.8 ± 12.9 (75.5-132.5); body mass index (BMI, kg/m(2)), 36.7 ± 3.8 (28.1-46.6). A mean 8.2 suture-anchor plications were placed in the fundus, 3.0 along the distal body wall. Mean operative time, 69.2 ± 26.6 min (32.0-126.0); patients were discharged in <24 h. Six-month mean AW was 87.0 ± 10.3 (68.0-111.5); BMI decreased 5.8 to 31.3 ± 3.3 (25.1-38.6) (p < 0.001); EWL was 49.4 %; TBWL, 15.5 %. No mortality or operative morbidity. Minor postoperative side effects resolved with treatment by discharge. Patients reported less hunger and earlier satiety post procedure. Liquid intake began 12 h post procedure with full solids by 6 weeks.

CONCLUSIONS

At 6-month follow-up of a prospective case series, the POSE procedure appeared to provide safe and effective weight loss without the scarring, pain, and recovery issues of open and laparoscopic bariatric surgery. Long-term follow-up and further study are required.

Bone and mineral metabolism in patients undergoing Roux-en-Y gastric bypass

Despite effective weight reduction, the impact of bariatric surgery on bone is a major concern. Mechanisms include decreased mechanical loading, calcium and vitamin D malabsorption, deficiency in other nutrients, and alterations in fat- and gut-derived hormones. The evidence to support clinical care pathways to prevent bone loss and fractures is at this point weak.

INTRODUCTION

There is a growing concern regarding the potential deleterious impact of bariatric surgery on bone metabolism. This comprehensive review addresses this controversial topic.

METHODS

We reviewed and analyzed articles evaluating bone metabolism and mechanisms for the ensuing putative bone loss in adult patients exclusively undergoing Roux-en-Y gastric bypass (RYGB) surgery, for the period spanning 1942 till September 2012.

RESULTS

Mechanisms identified to contribute to alterations in bone metabolism after bypass surgery include: decreased mechanical loading, calcium and vitamin D malabsorption with secondary hyperparathyroidism, deficiency in other nutrients, in addition to alterations in adipokines, gonadal steroids, and gut-derived hormones favoring bone loss, with the exception of serotonin and glucagon-like peptide-1. The relative contribution of each of these hormones to changes in bone homeostasis after bypass surgery remains undefined. Bone loss reflected by a decline in bone mineral density (BMD) and an increase in bone turnover markers have been reported in many studies, limited for the most part by the exclusive use of dual energy X-ray absorptiometry. Well-designed long-term prospective trials with fractures as an outcome, and studies investigating the magnitude, reversibility, and impact of the observed metabolic changes on fracture outcomes are lacking.

CONCLUSION

Robust conclusions regarding bone loss and fracture outcome after RYGB surgery cannot be drawn at this time. Although not evidence based, baseline evaluation and sequential monitoring with measurement of BMD and calciotropic hormones seem appropriate, with adequate calcium and vitamin D replacement. Beneficial interventions remain unclear.

Fracture risk following bariatric surgery: a population-based study

The effects of bariatric surgery on skeletal health are poorly understood. We found that bariatric surgery patients are more prone to fracture when compared to the general population. While further studies of fracture risk in this population are needed, bone health should be discussed in bariatric surgery clinics.

INTRODUCTION

Bariatric surgery is an increasingly common treatment for medically complicated obesity. Adverse skeletal changes after bariatric surgery have been reported, but their clinical importance remains unknown. We hypothesized that bariatric surgery patients are at increased risk of fracture.

METHODS

We conducted a historical cohort study of fracture incidence among 258 Olmsted County, Minnesota, residents who underwent a first bariatric surgery in 1985-2004. Relative fracture risk was expressed as standardized incidence ratios (SIRs), while potential risk factors were evaluated by hazard ratios (HR) obtained from a time-to-fracture regression model.

RESULTS

The mean (±SD) body mass index at bariatric surgery was 49.0 ± 8.4 kg/m(2), with an average age of 44 ± 10 years and 82% (212) females. Gastric bypass surgery was performed in 94% of cases. Median follow-up was 7.7 years (range, 6 days to 25 years), during which 79 subjects experienced 132 fractures. Relative risk for any fracture was increased 2.3-fold (95% confidence interval (CI), 1.8-2.8) and was elevated for a first fracture at the hip, spine, wrist, or humerus (SIR, 1.9; 95% CI, 1.1-2.9), as well as for a first fracture at any other site (SIR, 2.5; 95% CI, 2.0-3.2). Better preoperative activity status was associated with a lower age-adjusted risk (HR, 0.4; 95% CI, 0.2-0.8) while prior fracture history was not associated with postoperative fracture risk.

CONCLUSIONS

Bariatric surgery, which is accompanied by substantial biochemical, hormonal, and mechanical changes, is associated with an increased risk of fracture.

Bariatric surgery versus non-surgical treatment for obesity: a systematic review and meta-analysis of randomised controlled trials

OBJECTIVE

To quantify the overall effects of bariatric surgery compared with non-surgical treatment for obesity.

DESIGN

Systematic review and meta-analysis based on a random effects model.

DATA SOURCES

Searches of Medline, Embase, and the Cochrane Library from their inception to December 2012 regardless of language or publication status.

ELIGIBILITY CRITERIA

Eligible studies were randomised controlled trials with ≥ 6 months of follow-up that included individuals with a body mass index ≥ 30, compared current bariatric surgery techniques with non-surgical treatment, and reported on body weight, cardiovascular risk factors, quality of life, or adverse events.

RESULTS

The meta-analysis included 11 studies with 796 individuals (range of mean body mass index at baseline 30-52). Individuals allocated to bariatric surgery lost more body weight (mean difference -26 kg (95% confidence interval -31 to -21)) compared with non-surgical treatment, had a higher remission rate of type 2 diabetes (relative risk 22.1 (3.2 to 154.3) in a complete case analysis; 5.3 (1.8 to 15.8) in a conservative analysis assuming diabetes remission in all non-surgically treated individuals with missing data) and metabolic syndrome (relative risk 2.4 (1.6 to 3.6) in complete case analysis; 1.5 (0.9 to 2.3) in conservative analysis), greater improvements in quality of life and reductions in medicine use (no pooled data). Plasma triglyceride concentrations decreased more (mean difference -0.7 mmol/L (-1.0 to -0.4) and high density lipoprotein cholesterol concentrations increased more (mean difference 0.21 mmol/L (0.1 to 0.3)). Changes in blood pressure and total or low density lipoprotein cholesterol concentrations were not significantly different. There were no cardiovascular events or deaths reported after bariatric surgery. The most common adverse events after bariatric surgery were iron deficiency anaemia (15% of individuals undergoing malabsorptive bariatric surgery) and reoperations (8%).

CONCLUSIONS

Compared with non-surgical treatment of obesity, bariatric surgery leads to greater body weight loss and higher remission rates of type 2 diabetes and metabolic syndrome. However, results are limited to two years of follow-up and based on a small number of studies and individuals.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42012003317 (www.crd.york.ac.uk/PROSPERO).

The Official Positions of the International Society for Clinical Densitometry: Indications of Use and Reporting of DXA for Body Composition

The technique of body composition by dual-energy X-ray absorptiometry (DXA) has been used for several years in the research environment. Its ability to accurately and precisely measure lean, fat, and mineral composition in various body compartments has been well validated. Furthermore, the technique is widely available to clinical patients on existing DXA instruments throughout the world through the use of specific software packages and scanning algorithms. There have been few clear statements regarding the clinical indications for body composition measurement in patients outside the research setting. This is in part because of the lack of specific documented interventions that would be affected by body composition test results, beyond usual clinical advice. We have examined a few of the most common, specific scenarios (HIV therapy, sarcopenia, bariatric surgery, obesity) and proposed indications for body composition assessment. We have also discussed contraindications to body composition testing.

Weight loss surgery for mild to moderate obesity: a systematic review and economic evaluation

BACKGROUND

A systematic review and economic evaluation was commissioned to determine the effectiveness and cost-effectiveness of bariatric surgery for mild [class I, body mass index (BMI) 30 to 34.99] or moderate (class II, BMI 35 to 39.99) obesity.

METHODS

We searched 17 electronic resources (to February 2010) and other sources. Studies meeting predefined criteria were identified, data-extracted and assessed for risk of bias using standard methodology. A model was developed to estimate cost-effectiveness.

RESULTS

Two RCTs were included. Evidence from both indicated a statistically significant benefit from laparoscopic adjustable banding (LAGB) compared to a non-surgical comparator for weight loss and in obesity-related comorbidity. Both interventions were associated with adverse events. LAGB costs more than non-surgical management. For people with class I or II obesity and type 2 diabetes (T2D), the incremental cost-effectiveness ratio (ICER) at 2 years is £20,159, reducing to £4,969 at 5 years and £1,634 at 20 years. Resolution of T2D makes the greatest contribution to this reduction. In people with class I obesity, the ICER is £63,156 at 2 years, £17,158 at 5 years, and £13,701 at 20 years. Cost-effectiveness results are particularly sensitive to utility gain from reduction in BMI, factors associated with poorer surgical performance and diabetes health state costs.

CONCLUSIONS

Bariatric surgery appears to be a clinically effective and cost-effective intervention for people with class I or II obesity who also have T2D but is less likely to be cost-effective for people with class I obesity.

Bariatric surgery, bone loss, obesity and possible mechanisms

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

Bariatric surgery versus conventional therapy in obese Korea patients: a multicenter retrospective cohort study

PURPOSE

In Korea, the results of bariatric surgery have not been compared with those of nonsurgical treatment. The purpose of this study was to evaluate the effectiveness and safety of bariatric surgery vs. conventional nonsurgical treatment in severely obese Koreans.

METHODS

In this retrospective cohort study, we reviewed the medical charts of 261 consecutive subjects who underwent bariatric surgery and 224 subjects who were treated with weight control medication and lifestyle modification therapy between January 2008 and February 2011. Measures of clinical effectiveness, including change in weight (%) and comorbid diseases, and occurrence of complications, were investigated for 18 months after bariatric surgery.

RESULTS

Body mass index (BMI) was higher in the surgery group than in the conventionally treated group (mean ± standard deviation, 39.0 ± 6.2 vs. 34.3 ± 3.8). Diabetes was more prevalent in the surgery group than in the conventionally treated group (39.1% vs. 12.9%). The change in weight (%) between baseline and 18 months posttreatment was significantly greater in the surgery group (22.6%) than in the conventional therapy group (6.7%). While 57%, 47%, and 84% of subjects recovered from diabetes, hypertension, and dyslipidemia, respectively, in the surgery group, 10%, 20%, and 24% of subjects recovered from these conditions in the conventional group. Fifty-one subjects (19.5%) in the surgery group reported 61 complications (23.4%).

CONCLUSION

Bariatric surgery in Korea was significantly more effective than conventional treatment for weight loss and recovery from comorbidities such as diabetes, hypertension, and dyslipidemia, with a reasonable complication rate.

Laparoscopic greater curvature plication (LGCP) for treatment of morbid obesity in a series of 244 patients

BACKGROUND

Laparoscopic greater curvature plication (LGCP) is a new metabolic/bariatric surgical procedure that requires no resection, bypass, or implantable device. We report LGCP outcomes in 244 morbidly obese patients.

METHODS

Between 2010 and 2011, patients underwent LGCP. Body mass index (BMI, kilogram per square meter) evolution, excess BMI loss (%EBMIL), excess weight loss (%EWL), complications, and type 2 diabetes mellitus (T2DM) changes were recorded. Repeated-measures analysis of variance (ANOVA) was used to assess weight change at 6, 12, and 18 months. Subgroup analyses were conducted to provide benchmark outcomes at 6 months. Logistic regression was used to identify characteristics predictive of suboptimal weight loss.

RESULTS

Mean baseline BMI (±SD) was 41.4 ± 5.5 (80.7 % women, mean age 46.1 ± 11.0 years, 68 [27.9 %] patients had T2DM). Mean operative time was 70.6 min; mean hospitalization, 36 h (24-72). Sixty-eight patients (27.9 %) experienced postoperative nausea and/or vomiting that was controlled within 36 h. There was no mortality. Major complication rate was 1.2 % (n = 3). Repeated-measures ANOVA indicated significant weight loss across time points (p < 0.001). At 6 months (n = 105), BMI, %EBMIL, and %EWL were 36.1 ± 4.7, 34.8 ± 17.3, and 31.8 ± 15.9. Preoperative BMI was the only predictor of weight loss. Patients with BMI <40 lost more weight than those ≥40, although by 9 months, differences were no longer significant. In patients with preoperative BMI <40, 18-month %EWL approached 50 % and %EBMIL exceeded 50 %. At 6 months, 96.9 % of patients' T2DM was significantly improved/resolved.

CONCLUSIONS

Over the short term, LGCP results in effective weight loss and significant T2DM reduction with a very low rate of complications.

Evaluation of measurement of fat mass reduction after liposuction in obese patients

Body composition measurements are used to evaluate surgical treatment, such as bariatric surgery in overweight patients. Nowadays, there are many different methods to measure body composition available. However, none of them has been validated for use in patients after operation. The aim of the present study was to compare the amount of surgically removed fat with two different methods, bioelectrical impedance analysis (BIA) and total body potassium (TBK). Amount of removed fat during liposuction was measured 1, 2, 3, 4, 14 days, and 1 year postoperatively in 27 obese patients after liposuction. The results were compared with actual removed fat during the operation. The median fat mass removed was 4020 grams (range 1954-9655). Postoperatively there was a varying reduction in fat mass, as measured with BIA and with TBK. There was a clear difference between the range of amounts removed measured with BIA and the range of amount removed measured with TBK. This study indicates that BIA, but not TBK, is an appropriate method to measure fat mass in obese subjects in a surgical setting. BIA seems to underestimate the amount of fat removed, whereas TBK seems to overestimate it.

A review of unmet needs in obesity management

The prevalence of obesity continues to escalate in the USA; however, there is no consensus regarding the optimal therapy for obesity. For the vast majority of severely obese patients, conventional medical therapies (i.e., diet, exercise, behavioral counseling) often fail over the long term. Existing pharmacotherapy adjunctive to behavioral therapy has limited effectiveness and an imperfect safety record. In contrast, bariatric surgery has a high degree of weight loss efficacy, yet only a small fraction of the qualifying obese population undergoes these procedures because of the associated perioperative risks and potential late complications. In addition, the role of bariatric surgery is unclear in certain patient populations, such as patients with lower body mass index (BMI, 30-35 kg/m(2)), the high-risk super-super obese patients (BMI > 60), the morbidly obese adolescent, and obese patients requiring weight reduction in preparation for other procedures, such as orthopedic, transplant, or vascular surgeries. In these circumstances, there is a need for an effective but less invasive treatment to bridge the gap between medical and surgical therapy. This review examines current treatment outcomes, identifies prominent areas of unmet clinical needs, and provides an overview of two minimally invasive "temporary procedures for weight loss" that may eventually address some of the unmet needs in obesity management.

Very-low-energy diets and morbidity: a systematic review of longer-term evidence

Evidence from the literature supports the safe use of very-low-energy diets (VLED) for up to 3 months in supervised conditions for patients who fail to meet a target weight loss using a standard low-fat, reduced-energy approach. There is, however, a need for longer-term outcomes on obesity and associated morbidities following a VLED. The present systematic review aims to investigate longer-term outcomes from studies using VLED, with a minimum duration of 12 months, published between January 2000 and December 2010. Studies conducted in both children and adults, with a mean/median BMI of ≥ 28 kg/m2 were included. PubMed, MEDLINE, Web of Science and Science Direct were searched. Reference lists of studies and reviews were manually searched. Weight loss or prevention of weight gain and morbidities were the main outcomes assessed. A total of thirty-two out of 894 articles met the inclusion criteria. The duration of the studies ranged from 12 months to 5 years. Periods of VLED ranged from 25 d to 9 months. Several studies incorporated aspects of behaviour therapy, exercise, low-fat diets, low-carbohydrate diets or medication. Current evidence demonstrates significant weight loss and improvements in blood pressure, waist circumference and lipid profile in the longer term following a VLED. Interpretation of the results, however, was restricted and conclusions with which to guide best practice are limited due to heterogeneity between the studies. The present review clearly identifies the need for more evidence and standardised studies to assess the longer-term benefits from weight loss achieved using VLED.

Treatment and management of obesity: is surgical intervention the answer?

Obesity is rapidly becoming a major health concern and could be considered equal to smoking as a preventable cause of premature death. The National Institute for Health and Clinical Excellence (NICE 2006) estimated that 1.1 billion people are overweight, a number rivalling those who are underweight globally. Recent statistics for England from the National Health Service (NHS 2011) report that in 2009/10 there were 7,214 bariatric surgical procedures performed on people of varying ages.

Comparison of laparoscopic adjustable gastric banding (LAGB) with other bariatric procedures; a systematic review of the randomised controlled trials

BACKGROUND

Bariatric surgery can provide efficient weight loss and improvement in obesity-related co-morbidities in adults. Laparoscopic adjustable gastric banding (LAGB) comprised 30.3% of all bariatric procedures between 2009 and 2010 in the UK. This review evaluates the level 1 evidence for change in co-morbidities, quality of life (QoL) and weight provided by LAGB compared with other bariatric procedures.

METHOD

Systematic literature search of MEDLINE, EMBASE and CENTRAL (1988 to May 2011) was performed. Only randomised controlled trials (RCTs) were included. Studies with non-surgical comparators, open gastric banding procedures or adolescent participants were excluded. Primary outcome was change in co-morbidities. Secondary outcomes included QoL, weight loss, complications, operation time and length of stay.

RESULTS

Five RCTs met the inclusion criteria. Vertical banded gastroplasty, sleeve gastrectomy and gastric bypass were compared to LAGB. Co-morbidities were reported in two studies and QoL in one. LAGB was comparable to other procedures for both of these outcomes. All five trials showed LABG to be effective in weight loss, however all comparative procedures resulted in greater weight loss. Operative time and length of hospital stay were significantly shorter with LAGB. Short-term complications were found to be consistently lower in the LAGB group. Evidence was divided with respect to long-term complications.

CONCLUSION

Co-morbidities and QoL are poorly reported and showed no difference between LAGB and other bariatric procedures. Evidence suggests that LAGB is not the most effective surgical procedure to reduce weight. LAGB is associated with lower early complications and shorter operative time and length of stay, and therefore may be preferable to patients.

[Clinical practice guidelines for evaluation and treatment of osteoporosis associated to endocrine and nutritional conditions. Bone Metabolism Working Group of the Spanish Society of Endocrinology]

OBJECTIVE

To provide practical recommendations for evaluation and treatment of osteoporosis associated to endocrine diseases and nutritional conditions.

PARTICIPANTS

Members of the Bone Metabolism Working Group of the Spanish Society of Endocrinology, a methodologist, and a documentalist.

METHODS

Recommendations were formulated according to the GRADE system (Grading of Recommendations, Assessment, Development, and Evaluation) to describe both the strength of recommendations and the quality of evidence. A systematic search was made in MEDLINE (Pubmed), using the following terms associated to the name of each condition: AND "osteoporosis", "fractures", "bone mineral density", and "treatment". Papers in English with publication date before 18 October 2011 were included. Current evidence for each disease was reviewed by two group members, and doubts related to the review process or development of recommendations were resolved by the methodologist. Finally, recommendations were discussed in a meeting of the Working Group.

CONCLUSIONS

The document provides evidence-based practical recommendations for evaluation and management of endocrine and nutritional diseases associated to low bone mass or an increased risk of fracture. For each disease, the associated risk of low bone mass and fragility fractures is given, recommendations for bone mass assessment are provided, and treatment options that have shown to be effective for increasing bone mass and/or to decreasing fragility fractures are listed.

Pragmatic study of orlistat 60 mg on abdominal obesity

BACKGROUND/OBJECTIVES

It is well established that combining a reduced calorie, low-fat diet with the lipase inhibitor orlistat results in significantly greater weight loss than placebo plus diet. This weight loss is accompanied by changes in adipose tissue (AT) distribution. As 60 mg orlistat is now available as an over-the-counter medication, the primary objective of this study was to determine whether 60 mg orlistat is effective as a weight loss option in a free-living community population with minimal professional input.

METHODS

AT and ectopic lipid content were measured using magnetic resonance imaging and (1)H MR spectroscopy, respectively, in 27 subjects following 3 months treatment with orlistat 60 mg and a reduced calorie, low-fat diet.

RESULTS

Significant reductions in intra-abdominal AT (-10.6%, P=0.023), subcutaneous (-11.7% P<0.0001) and pericardial fat (-9.8%, P=0.034) volumes and intrahepatocellular lipids (-43.3%, P=0.0003) were observed. These changes in body fat content and distribution were accompanied by improvements in plasma lipids and decreases in blood pressure and heart rate.

CONCLUSION

These findings suggest that over-the-counter 60 mg orlistat, in combination with the type of advice a subject could expect to be given when obtaining 60 mg orlistat in a community setting, does indeed result in potentially clinically beneficial changes in body composition and risk factors for metabolic diseases.

Endocrine and nutritional management of the post-bariatric surgery patient: an Endocrine Society Clinical Practice Guideline

OBJECTIVE

We sought to provide guidelines for the nutritional and endocrine management of adults after bariatric surgery, including those with diabetes mellitus. The focus is on the immediate postoperative period and long-term management to prevent complications, weight regain, and progression of obesity-associated comorbidities. The treatment of specific disorders is only summarized.

PARTICIPANTS

The Task Force was composed of a chair, five additional experts, a methodologist, and a medical writer. It received no corporate funding or remuneration.

CONCLUSIONS

Bariatric surgery is not a guarantee of successful weight loss and maintenance. Increasingly, patients regain weight, especially those undergoing restrictive surgeries such as laparoscopic banding rather than malabsorptive surgeries such as Roux-en-Y bypass. Active nutritional patient education and clinical management to prevent and detect nutritional deficiencies are recommended for all patients undergoing bariatric surgery. Management of potential nutritional deficiencies is particularly important for patients undergoing malabsorptive procedures, and strategies should be employed to compensate for food intolerance in patients who have had a malabsorptive procedure to reduce the risk for clinically important nutritional deficiencies. To enhance the transition to life after bariatric surgery and to prevent weight regain and nutritional complications, all patients should receive care from a multidisciplinary team including an experienced primary care physician, endocrinologist, or gastroenterologist and consider enrolling postoperatively in a comprehensive program for nutrition and lifestyle management. Future research should address the effectiveness of intensive postoperative nutritional and endocrine care in reducing morbidity and mortality from obesity-associated chronic diseases.

Comparison of DXA and water measurements of body fat following gastric bypass surgery and a physiological model of body water, fat, and muscle composition

Measurement of body composition changes following bariatric surgery is complicated because of the difficulty of measuring body fat in highly obese individuals that have increased photon absorption and are too large for the standard dual-energy X-ray absorptiometry (DXA) table. We reproducibly measured body composition from half-body DXA scans and compared the values of total body fat estimated from total body water (TBW) and DXA measurements before and after Roux-en-Y gastric bypass surgery (RYGB). DXA, TBW (deuterium dilution), extracellular water (ECW; bromide dilution), and intracellular water (ICW) measurement (by subtraction) were made before surgery and at 2 wk, 6 wk, 6 mo, and 12 mo after surgery. Twenty individuals completed baseline and at least four follow-up visits. DXA appeared to underestimate the fat and bone mass in extreme obesity (before surgery), whereas at 6 and 12 mo after surgery, the DXA and TBW fat measurements were similar. The ECW-to-ICW ratio was increased in obese individuals and increased slightly more after surgery. We describe a new model that explains this abnormal water composition in terms of the normal physiological changes that occur in body composition in obesity and weight loss. This model is also used to predict the muscle mass loss following RYGB.

New fat free mass - fat mass model for use in physiological energy balance equations

Background

The Forbes equation relating fat-free mass (FFM) to fat mass (FM) has been used to predict longitudinal changes in FFM during weight change but has important limitations when paired with a one dimensional energy balance differential equation. Direct use of the Forbes model within a one dimensional energy balance differential equation requires calibration of a translate parameter for the specific population under study. Comparison of translates to a representative sample of the US population indicate that this parameter is a reflection of age, height, race and gender effects.

Results

We developed a class of fourth order polynomial equations relating FFM to FM that consider age, height, race and gender as covariates eliminating the need to calibrate a parameter to baseline subject data while providing meaningful individual estimates of FFM. Moreover, the intercepts of these polynomial equations are nonnegative and are consistent with observations of very low FM measured during a severe Somali famine. The models preserve the predictive power of the Forbes model for changes in body composition when compared to results from several longitudinal weight change studies.

Conclusions

The newly developed FFM-FM models provide new opportunities to compare individuals undergoing weight change to subjects in energy balance, analyze body composition for individual parameters, and predict body composition during weight change when pairing with energy balance differential equations.

Bariatric surgery: a cost-effective intervention for morbid obesity; functional and nutritional outcomes

Obesity has been described as the health crisis of the 21st century. It is a chronic lifelong medical condition, whose pattern often starts in childhood, and is demographically worsening in every developed country. The cost of treating the many medical conditions associated with obesity threatens to overwhelm healthcare resources. Medical treatments produce at most no more than 10% weight loss in the severely obese, with high failure rates. In this article, we review the available evidence regarding long-term reduction in weight, reduced mortality and improvement in most, if not all, obesity-related comorbidities. There is a need for daily multivitamins and extra minerals, especially with gastric bypass, and nutritional deficiencies of vitamins D and B12, Ca, Fe and folate need monitoring and prevention. Currently there is no medical therapy on the near horizon that will match the effect of surgery, which, if done safely, remains the only effective therapy. Bariatric surgery is cost effective, and health providers should embrace the development and rapid expansion of services.