|Year : 2015 | Volume
| Issue : 2 | Page : 90-96
Effect of intragastric balloon-induced weight loss on body composition, fatty liver, and comorbidities in Egyptian middle-aged obese women: a 6-month follow-up study
Mohammed M Shamseya MD , Marwa A Madkour
Department of Clinical and Experimental Internal Medicine, Faculty of Medicine, Medical Research Institute, University of Alexandria, Alexandria, Egypt
|Date of Submission||21-Feb-2015|
|Date of Acceptance||13-Aug-2015|
|Date of Web Publication||23-Nov-2015|
Mohammed M Shamseya
Department of Clinical and Experimental Internal Medicine, Faculty of Medicine, Medical Research Institute, University of Alexandria, Alexandria
Source of Support: None, Conflict of Interest: None
Paralleling the increasing prevalence of obesity in the Egyptian population, metabolic syndrome and liver steatosis are also on the rise. Body composition measurement is used to describe the percentages of fat, bone, water, and muscle in human bodies. The available classic weight loss treatments such as low-calorie diet, exercise, behavioral modification, and pharmacotherapy usually achieve only limited weight loss. The BioEnterics Intragastric Balloon (BIB) is an endoscopic liquid-filled device for the treatment of obesity.
The aim of this study was to examine the safety of BIB insertion in a group of obese middle-aged Egyptian women treated with intragastric balloon to induce weight loss for 6 months and report its effect on their anthropometric measurements, body composition, fatty liver, and comorbidities.
Patients and methods
During the period from February 2012 until August 2013, 47 consecutive middle-aged female patients were enrolled for BIB insertion. Inclusion criteria were mainly based on the BMI (≥30.0 kg/m 2 ) and on associated comorbidities. Apart from physical and anthropometric evaluation, body composition analysis was performed using a bioelectrical impedance analyzer to estimate fat mass, body fat percentage, and fat-free mass. The Adult Treatment Panel III criteria were used to diagnose metabolic syndrome, and ultrasound evaluation of the liver for the presence and grade of steatosis was performed. BIB placement was carried out after diagnostic endoscopy, under intravenous conscious or unconscious sedation.
The total percentage of complications from BIB insertion was 12.8%, which were mostly mild and reversible. Three (6.4%) patients had their gastric balloon removed early (two voluntarily and one due to de-novo peptic ulcer) and were excluded from the study, whereas the remaining 44 patients continued their 6-month therapy duration. Overall, BIB insertion significantly reduced weight from a mean value of 96.82 ± 14.18 kg at baseline to 83.45 ± 12.03 kg after 6 months (P < 0.001). The mean value for the amount of weight lost at endpoint was 13.36 ± 3.29 kg, whereas the mean value for BMI lost at the time of BIB removal was 5.12 ± 1.20 kg/m 2 , which was a significant reduction compared with baseline values (P < 0.001). No significant change occurred in the liver size over the 6-month study period (P = 0.12), whereas a significant decrease in the grade of steatosis was noted. Body fat mass and body fat percentage with bioelectrical impedance analyzer were significantly reduced (P < 0.001). However, there was also a significant decline in fat-free mass (P < 0.001). Significant favorable changes in the biochemical markers of metabolic syndrome, homeostasis model assessment of insulin resistance index, and liver profile also occurred. An overall 4.6% of patients showed resolution, whereas 31.8% showed improvement in the features of metabolic syndrome.
This study provides anthropometric, biochemical, and body composition evidence on significant improvement in metabolic syndrome, obesity-associated comorbidities, and fatty liver after weight loss induced by the minimally invasive and relatively safe technique. However, it is recommended to continue a weight-reducing diet after BIB removal for achieving long-term effectiveness and to add exercise programs to dietary restriction for promoting more favorable change in body composition.
Keywords: BIB, body composition, intragastric balloon, obesity, metabolic syndrome, weight
|How to cite this article:|
Shamseya MM, Madkour MA. Effect of intragastric balloon-induced weight loss on body composition, fatty liver, and comorbidities in Egyptian middle-aged obese women: a 6-month follow-up study. Egypt J Obes Diabetes Endocrinol 2015;1:90-6
|How to cite this URL:|
Shamseya MM, Madkour MA. Effect of intragastric balloon-induced weight loss on body composition, fatty liver, and comorbidities in Egyptian middle-aged obese women: a 6-month follow-up study. Egypt J Obes Diabetes Endocrinol [serial online] 2015 [cited 2017 Oct 17];1:90-6. Available from: http://www.ejode.eg.net/text.asp?2015/1/2/90/170207
| Introduction|| |
The WHO estimated that, by the year 2015, 2.3 billion people will be overweight and 700 million will be obese worldwide . The Middle East, including the Gulf area and North Africa, is no exception to the worldwide increase in obesity. In 1996, a study  showed that the Egyptian population had the highest BMI in the world, averaging 26.3 kg/m 2 . In 2002, 45% of urban Egyptian women and 20% of the rural population were proved obese .
The rates of obesity grew in Egypt mainly because since the 1990s fats and carbohydrates became more heavily consumed. Furthermore, food is traditionally the center of social events and special occasions in the Egyptian society, whereas the health conscious exercise culture is confined only to the higher socioeconomic class. As parents teach this lifestyle to their children, the prevalence of obesity among children and adolescents increases . In addition, women are more likely to be overweight or obese due to the cultural appreciation of heavier female bodies and the perception of appropriate female behavior and occupations, particularly in rural areas ,.
Contrary to past concepts, obesity is now considered a chronic resistant disease with major morbidity and mortality. Paralleling the increasing prevalence of obesity in the general population the metabolic syndrome is now on the rise. Hypertension, coronary artery disease, diabetes, hypercholesterolemia, osteoarthritis, and nonalcoholic fatty liver disease (NAFLD) have become major issues of concern worldwide ,. The clinical implications of this alarming prevalence of NAFLD are derived from the fact that it may progress to cirrhosis, liver failure, and hepatocellular carcinoma .
The most commonly used indicators for obesity are BMI, waist circumference (WC), and waist-to-hip ratio (WHR). Body composition measurement is used to describe the percentages of fat, bone, water, and muscle in human bodies. Body composition [particularly body fat percentage (BF%)] can be measured in several ways, including skinfold thickness, dual energy X-ray absorptiometry, and bioelectrical impedance analyzer (BIA) .
According to the current guidelines, weight-reduction programs in overweight and obese individuals should include an initial 6-month period of weight loss, followed by a second phase of weight maintenance over 24 months ,,. The goal of the weight loss phase is to achieve a sustained minimum of 10% weight loss to prevent or to reduce the risk for cardiovascular and other obesity-related disorders. The first approach in addressing the multifaceted problem of obesity should consist of a combination of a calorie-restricted diet, physical activity, and behavior modification ,. For motivated patients who seriously attempt but fail to achieve a weight loss of 5-10% in 3-6 months, pharmacotherapy is recommended. According to the American National Institute of Health, bariatric surgery should be offered to patients with BMI higher than 40 kg/m 2 , or BMI higher than 35 kg/m 2 with obesity-related medical conditions, such as diabetes, cardiovascular disease, and obstructive sleep apnea . However, there is an intermediate group of patients who do not respond to medical therapy and who are not yet surgical candidates. For this group, another option, the intragastric balloon, has received more attention in the last two decades. Moreover, it has been recommended as an adjuvant for weight reduction before all kinds of planned surgical procedures in the morbidly obese, to reduce surgical risk ,.
The BioEnterics Intragastric Balloon (BIB) is an endoscopic device for temporary treatment of obesity. Randomized sham-controlled trials have shown that this liquid-filled intragastric balloon decreases preprandial hunger, increases postprandial satiety, and promotes weight loss in the short term, whereas on the long term it helps individuals modify their eating habits by providing a self-education tool ,.
We prospectively followed up a group of obese middle-aged Egyptian women treated with intragastric balloon to induce weight loss for 6 months and reported its effect on their anthropometric measurements, body composition, fatty liver, and comorbidities.
| Patients and methods|| |
During the period from February 2012 until August 2013, 47 consecutive middle-aged female patients attending the Hepatology and Gastrointestinal Endoscopy Unit (Medical Research Institute, Alexandria University, Alexandria, Egypt) for BIB placement were enrolled in the study. Inclusion criteria were mainly based on the BMI (≥30.0 kg/m 2 ) and on associated comorbidities. Written informed consent was obtained from all treated patients. Medical, dieting, and weight histories were taken (plus a bariatric surgeon and a psychiatrist consultation if necessary), followed by physical examination and anthropometry. On the basis of BMI values, obesity was categorized as follows: class IV, BMI of 50 kg/m 2 or greater; class III, BMI of 40-49.9 kg/m 2 ; class II, BMI of 35-39.9 kg/m 2 ; and class I, BMI of 30-34.9 kg/m 2 . A BIA (Tanita TBF-310; Tanita Corporation, Tokyo, Japan) was used to estimate fat mass (FM), BF%, and fat-free mass (FFM) .
Exclusion criteria were as follows: endocrinal or genetic cause for the obese state, malignancy within the previous 5 years, pregnancy, drug abuse, chronic therapy with steroids, NSAIDs, anticoagulants, or antiobesity drugs. Contraindications specifically related to the balloon included gastrointestinal lesions [e.g. a large (>5 cm) hiatal hernia], Los Angeles grade C-D esophagitis, peptic ulceration, varices or gastric antral vascular ectasia, and previous bariatric or abdominal surgery (because of the potential presence of adhesions). Blood samples were obtained for evaluating fasting blood glucose, serum insulin, lipid profile, liver transaminases, and g-glutamyl transpeptidase at baseline and after therapy completion. The homeostasis model assessment of insulin resistance (HOMA-IR) index was calculated as fasting plasma glucose (mg/dl) multiplied by fasting serum insulin (mU/l) divided by 405 .
The Adult Treatment Panel III criteria were used to diagnose metabolic syndrome. The presence of at least three of the following five conditions was diagnostic of metabolic syndrome: WC greater than 88 cm (for women); serum triglyceride level of at least 150 mg/dl; high-density lipoprotein cholesterol level of less than 50 mg/day (for women); blood pressure of at least 130/85 mmHg; or serum fasting glucose level of at least 110 mg/dl .
Ultrasound evaluation of the liver for the presence and grade of steatosis was performed before balloon insertion and after removal using a convex-type real-time electronic transducer (Siemens G50; Siemens, Seoul, South Korea). The severity of liver steatosis was estimated with a comparative assessment of image brightness of the liver relative to the kidneys (mild), blurring of hepatic veins (moderate), or far gain attenuation (severe) .
BIB placement was performed (Allergan, Irvine, California, USA) after diagnostic endoscopy, under intravenous conscious or unconscious sedation . The BIB was inflated under direct vision with saline (500-700 ml) mixed with methylene blue (10 ml) solution. The patient was monitored for 3 h to verify tolerance to the balloon. During the following 3 days, patients were contacted daily through telephone. Nausea, vomiting, abdominal cramps, and acid reflux were expected for 72 h and were not considered a complication. They were treated with antiemetic, antispasmodic, and/or acid suppressant medications. Instructions for a 72-h postinsertion liquid diet were provided, followed by a 1000 Kcal diet (carbohydrates 146 g, lipid 68 g, and proteins 1 g/kg ideal weight) under the supervision of professional dietitians (Nutrition Clinic, High Institute of Public Health, Alexandria University, Alexandria, Egypt). After 6 months, endoscopy was performed and balloon removal was carried out. During the 6-month therapy duration patients were followed up monthly for assessment and recording of complications, comorbidities, and weight loss.
| Results|| |
Forty-seven middle-aged female patients were enrolled in the study for BIB placement. Their ages ranged from 43 to 59 years with a mean value of 51.4 ± 7.2 years, and only two (4.3%) patients were smokers.
[Table 1] presents the main complications encountered after the first week of BIB insertion and throughout the 6-month therapy duration, including early balloon removal. During the first 72 h after BIB insertion, 33 (70.2%) patients reported nausea, vomiting, acid reflux, and mild abdominal pain, which were successfully managed with medical therapy in the majority of cases. Three (6.4%) patients had their gastric balloon removed early (two voluntarily and one due to de-novo peptic ulcer) and were excluded from the study, whereas the remaining 44 patients continued their 6-month therapy duration. [Figure 1] shows the steps for endoscopic insertion of BIB in one of the patients.
|Figure 1: Steps for endoscopic insertion of BioEnterics Intragastric Balloon (BIB) in one of the patients. (a) Endoscopic picture of the gastric lumen showing BIB Placement Catheter Assembly while the balloon is still uninflated. The balloon must be below the lower esophageal sphincter and well within the stomach cavity. (b) Endoscopic picture of the gastric lumen showing partially infl ated BIB in situ (300 ml of sterile saline). (c) Endoscopic picture of the gastric lumen showing fully inflated BIB in situ (700 ml of sterile saline). (d) Endoscopic picture of the gastric lumen showing fully inflated BIB in situ at the end of 6-month therapy duration.|
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|Table 1: Reported complications after 1 week from BioEnterics Intragastric Balloon insertion|
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[Table 2] and [Figure 2] demonstrate the anthropometric measurements of patients at baseline (before BIB insertion) and endpoint (at the time of BIB removal). The baseline mean BMI value was 37.38 ± 4.65 kg/m 2 . None of our patients were of class IV obesity (BMI≥50 kg/m 2 ); 12 out of 44 (27.3%) patients were referred for morbid obesity (class III) to reduce body weight before surgery. Class I obesity was documented in 15 (34.1%) patients and class II in 17 (38.6%). Overall, BIB insertion significantly reduced weight from a mean value of 96.82 ± 14.18 kg at baseline to 83.45 ± 12.03 kg after 6 months (P < 0.001). The mean value of the weight lost was 13.36 ± 3.29 kg, whereas the mean value for BMI lost at the time of BIB removal was 5.12 ± 1.20 kg/m 2 , which was a significant reduction in endpoint compared with baseline values (P < 0.001). The percentage of weight loss was calculated in reference to initial total body weight, whereas the percentage of excess weight loss was calculated in relation to initial excess weight. The number of participants achieving 10% or greater percentage of weight loss threshold was 42 (95.4%). WC and WHR were also significantly reduced at the endpoint of the study compared with baseline values (P < 0.001).
|Figure 2: Anthropometric study of patients at baseline and endpoint. (a) Waist and hip measurements at baseline and endpoint (P < 0.001). (b) Waistto- hip ratio at baseline and endpoint (P < 0.001). (c) Body weight measurements at baseline and endpoint (P < 0.001). (d) BMI at baseline and endpoint (P < 0.001).|
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Ultrasound evaluation of fatty liver
[Table 3] summarizes the abdominal ultrasound of fatty liver changes in patients at baseline and endpoint. No significant change occurred in the liver size over the 6-month study period (P = 0.12). However, a significant decrease was noted in the grade of steatosis (P = 0.03), and three (6.8%) patients showed complete resolution of ultrasound features of steatosis.
|Table 3: Ultrasound study of liver steatosis in patients at baseline and endpoint|
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[Table 4] summarizes the laboratory test results of patients at baseline and endpoint of the study, showing significant changes in the biochemical markers of metabolic syndrome. Following weight loss, fasting blood glucose, serum insulin, HOMA-IR index, cholesterol, and triglyceride concentrations were lowered, whereas high-density lipoprotein was elevated. Liver profile parameters showed significant reduction, particularly serum g-glutamyl transpeptidase.
Body composition analysis
[Table 5] summarizes the results of body composition analysis of patients using BIA at baseline and endpoint of the study, with significant reduction in the body FM and BF% (P < 0.001). However, there was also a significant decline in FFM (P < 0.001).
|Table 5: Body composition study of patients with bioelectrical impedance analyzer at baseline and endpoint|
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Metabolic syndrome and comorbidities
[Table 6] and [Figure 3] illustrate the different comorbidities diagnosed in our patients at baseline and their re-evaluation 6 months later at the time of balloon removal. All participants who completed the study (n = 44) had one or more pre-existing comorbidities, which were either recognized through medical history taking from the patient, or incidentally diagnosed de novo during patient screening before balloon placement. Metabolic syndrome-associated, as well as other frequently reported, comorbidities such as respiratory symptoms (obstructive sleep apnea and/or exertional dyspnea) and joint pains were included. The resolution of comorbidities was defined as normalization of laboratory values or disappearance of physical symptoms and signs resulting in complete cessation of pharmacological therapy. Improvement in comorbidities was defined as requiring lower drug dosage, or shifting to milder therapy. All types of comorbidities showed statistically significant resolution/improvement at the time of BIB removal. Patients who showed resolution/improvement in comorbidities demonstrated significantly higher body weight loss (P = 0.02) and BF% loss (P < 0.001) compared with those who showed no change in comorbidities. No correlation was found between the presence of comorbidities at baseline and the occurrence of complications from BIB insertion (P = 0.17).
|Figure 3: Comorbidities at baseline and endpoint (%). HDL, high-density lipoprotein; TG, triglycerides.|
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| Discussion|| |
The classic weight loss treatment lines include low-calorie diet, exercise, behavioral modification, and pharmacotherapy. Because these modalities achieve modest and usually transient weight loss, bariatric surgery and other interventional modalities (such as the intragastric balloon) have emerged in the last two decades as an adjuvant line of therapy for patients with high BMI, particularly those with obesity-related medical conditions, such as diabetes, cardiovascular disease, and obstructive sleep apnea .
The effectiveness and safety of intragastric balloon have been a matter of debate for quite some time. In our work, the total percentage of complications from BIB insertion was 12.8%, which were mostly mild and reversible. This was not different from the results of Imaz et al. , who extracted data from 3442 patients treated with BIB and found that the majority of complications were mild. Although they admitted that the early removal rate was significant (4.2%), half of these removals, however, were voluntary. As regards the effectiveness of BIB in reducing weight, a review article in 2007 of nine randomized, controlled trials on 395 obese patients found little benefit of intragastric balloon placement for weight loss . However, another extensive meta-analysis  in 2008 collected data from 15 studies that used BIB on 3608 patients and estimated a pooled weight loss of 14.7 kg and a pooled BMI loss of 5.7 kg/m 2 . Our results showed similar numbers; the average weight lost at the time of BIB removal was 13.36 ± 3.29 kg, whereas the average BMI lost was 5.12 ± 1.20 kg/m 2 , demonstrating a significant reduction from baseline values for both parameters. It remains to be established, however, whether the beneficial effect of BIB-induced weight loss also translates into reduced rates of different obesity-related morbidities. Our participants who had the BIB placed and were kept on a 1000 Kcal diet throughout the follow-up period mostly showed a positive outcome as regards insulin sensitivity, hepatic steatosis, and features of the metabolic syndrome. Compared with baseline, 9.1% of our patients became normoglycemic, 18.2% became normotensive, 6.8% attained normal serum level of triglycerides, and 9.1% achieved normal high-density lipoprotein. Significant favorable changes in insulin sensitivity (in terms of HOMA-IR index) and liver steatosis (in terms of ultrasound image and liver enzymes) also occurred. In addition, 13.6% were totally cured from their respiratory symptoms and 22.7% were completely relieved from joint pains. Keeping in mind that the main contributory factor in the development of the metabolic syndrome is the accumulation of fat around the abdominal viscera and inside the intra-abdominal solid organs, this beneficial effect of BIB on comorbidities, fatty liver, and liver enzymes is likely attributed to loss of visceral fat. By reducing the size of the gastric reservoir, the intragastric device might induce a negative energy balance between dietary energy intake and energy expenditure .
In our study we did not include controls for comparison, but our primary aim was to examine the safety of BIB insertion, as well as its effect on liver steatosis and some components of the metabolic syndrome. In addition, we acknowledge that our assessment of liver steatosis with ultrasound and not using histology might have been suboptimal for the evaluation of the actual impact on liver tissue steatosis, which was mainly attributed to the refusal of most patients to undergo the invasive procedure of liver biopsy for no significant reason. This frequently encountered obstacle was in fact also reported in a study by Mattar et al. , in which 70 patients underwent liver biopsy after dramatic surgically induced weight loss. Although their results proved significant and widespread improvement or resolution of NAFLD and NASH, the authors admitted to their compulsion to obtain liver biopsies intraoperatively despite the possible technical and operator bias.
Another objective of our study was to measure the effect of BIB-induced weight loss for 6 months on body composition. A significant decline in body FM and BF% was recorded in our patients. However, there was also a significant reduction in FFM. Although the commonly used indicators for obesity are BMI, WC, and WHR, these indicators are limited by their inability to distinguish fat from muscle. BIA is a method used to determine the body composition, particularly body fat, FFM, and BF%. These measurements are equally important for any given weight-loss trial, not only because the reduction in body fat ultimately leads to a decrease in risk factors for metabolic syndrome but also because a concomitant decline in lean tissue can frequently be observed during a weight-reduction program - as was encountered in our study. Given that the FFM represents a key determinant of resting metabolic rate (RMR), thus a decrease in lean tissue could hinder the progress of weight loss by reducing the RMR. Losing FM when maintaining a constant FFM and RMR should be, therefore, a desirable goal for weight-reduction programs to achieve long-term effectiveness. Studies have proved that exercise training has great implications on decreasing the percentage of body fat while sustaining FFM. Hence, the addition of exercise programs to dietary restriction would act synergistically to encourage more favorable changes in body composition than separate diet or physical activity .
In conclusion, this study provides anthropometric, biochemical, and body composition evidence on significant improvement in metabolic syndrome, obesity-associated comorbidities, and fatty liver after weight loss induced by a minimally invasive and relatively safe technique. However, BIB insertion alone (similar to any other short-term weight loss modality) could be limited by high rates of relapse and weight regain after removal. Therefore, it is recommended to continue a weight-reducing diet after BIB removal for achieving long-term effectiveness, and to add exercise programs to dietary restriction for promoting more favorable change in body composition.
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Conflicts of interest
There are no conflicts of interest.
| References|| |
Martorell R, Khan LK, Hughes ML, Grummer-Strawn LM. Obesity in women from developing countries. Eur J Clin Nutr 2000; 54:247-252.
Galal OM. The nutrition transition in Egypt: obesity, undernutrition and the food consumption context. Public Health Nutr 2002; 5:141-148.
Batnitzky A. Obesity and household roles: gender and social class in Morocco. Sociol Health Illn 2008; 30:445-462.
Al-Nuaim AA, Bamgboye EA, Al-Rubeaan KA, Al-Mazrou Y. Overweight and obesity in Saudi Arabian adult population, role of socio-demographic variables. J Community Health 1997; 22:211-223.
Hu KC, Wang HY, Liu SC, Liu CC, Hung CL, Bair MJ, et al
. Nonalcoholic fatty liver disease: updates in noninvasive diagnosis and correlation with cardiovascular disease. World J Gastroenterol 2014; 20:7718-7729.
Marchesini G, Bugianesi E, Forlani G, Cerrelli F, Lenzi M, Manini R, et al
. Nonalcoholic fatty liver, steatohepatitis, and the metabolic syndrome. Hepatology 2003; 37:917-923.
Shibahara J, Ando S, Sakamoto Y, Kokudo N, Fukayama M Hepatocellular carcinoma with steatohepatitic features: a clinicopathological study of Japanese patients. Histopathology 2014; 64:951-962.
Erceg DN, Dieli-Conwright CM, Rossuello AE, Jensky NE, Sun S, Schroeder ET. The Stayhealthy bioelectrical impedance analyzer predicts body fat in children and adults. Nutr Res 2010; 30:297-304.
World Health Organization. Obesity: Preventing and managing the global epidemic. WHO Obesity Technical Report Series 894
. Geneva, Switzerland: World Health Organization; 2000.
Anonymous. Clinical guidelines on the identification, evaluation, and treatment of overweight and obesity in adults. The evidence report. National Institutes of Health. Obes Res 1998; 6:51S-209S.
World Health Organization. Obesity: Preventing and managing the global epidemic. Report of a WHO consultation on obesity. WHO/NUT/NCD/98.1. WHO Technical Support Series
. Geneva, Switzerland: World Health Organization; 1998:1-276.
Strychar I. Diet in the management of weight loss. Can Med Assoc J 2006; 174:56-63.
Glenny AM, O′Meara S, Melville A, Sheldon TA, Wilson C. The treatment and prevention of obesity: a systematic review of the literature. Int J Obes Relat Metab Disord 1997; 21:715-737.
National Institute of Health Conference. Gastrointestinal surgery for severe obesity. Consensus development conference panel. Ann Intern Med 1991; 115:956-961.
Ackroyd R, Mouiel J, Chevallier JM, Daoud F. Cost-effectiveness and budget impact of obesity surgery in patients with type-2 diabetes in three European countries. Obes Surg 2006; 16:1488-1503.
Franz MJ, VanWormer JJ, Crain AL, Boucher JL, Histon T, Caplan W, et al
. Weight-loss outcomes: a systematic review and meta-analysis of weight-loss clinical trials with a minimum 1-year follow-up. J Am Diet Assoc 2007; 107:1755-1767.
Sanmiguel CP, Haddad W, Aviv R, Cunneen SA, Phillips EH, Kapella W, et al
. The TANTALUS system for obesity: effect on gastric emptying of solids and ghrelin plasma levels. Obes Surg 2007; 17:1503-1509.
Mathus-Vliegen EM, Tytgat GN. Intragastric balloon for treatment-resistant obesity: safety, tolerance, and efficacy of 1-year balloon treatment followed by a 1-year balloon-free follow-up. Gastrointest Endosc 2005; 61:19-27.
Beeson WL, Batech M, Schultz E, Salto L, Firek A, Deleon M, et al
. Comparison of body composition by bioelectrical impedance analysis and dual-energy X-ray absorptiometry in Hispanic diabetics. Int J Body Compos Res 2010; 8:45-50.
Matthews DR, Hosker JP, Rudenski AS, Naylor BA, Treacher DF, Turner RC. Homeostasis model assessment: insulin resistance and beta-cell function from fasting plasma glucose and insulin concentrations in man. Diabetologia 1985; 28:412-419.
Ford ES, Giles WH, Dietz WH. Prevalence of the metabolic syndrome among US adults: findings from the third National Health and Nutrition Examination Survey. JAMA 2002; 287:356-359.
Palmentieri B, de Sio I, La Mura V, Masarone M, Vecchione R, Bruno S, et al.
The role of bright liver echo pattern on ultrasound B-mode examination in the diagnosis of liver steatosis. Dig Liver Dis 2006; 38:485-489.
Genco A, Bruni T, Doldi SB, Forestieri P, Marino M, Busetto L, et al
. BioEnterics Intragastric Balloon: the Italian Experience with 2,515 Patients. Obes Surg 2005; 15:1161-1164.
Imaz I, Martínez-Cervell C, García-Alvarez EE, Sendra-Gutiérrez JM, González-Enríquez J Safety and effectiveness of the intragastric balloon for obesity. A meta-analysis. Obes Surg 2008; 18:841-846.
Fernandes M, Atallah AN, Soares BGO, et al.
Intragastric balloon for obesity. Cochrane Database Syst Rev 2007; 24:CD004931.
Forlano R, Ippolito AM, Iacobellis A, Merla A, Valvano MR, Niro G, et al
. Effect of the BioEnterics intragastric balloon on weight, insulin resistance, and liver steatosis in obese patients. Gastrointest Endosc 2010; 71:927-933.
Mattar SG, Velcu LM, Rabinovitz M, Demetris AJ, Krasinskas AM, Barinas-Mitchell E, et al
. Surgically-induced weight loss significantly improves nonalcoholic fatty liver disease and the metabolic syndrome. Ann Surg 2005; 242:610-617.
Stiegler P, Cunliffe A. The role of diet and exercise for the maintenance of fat-free mass and resting metabolic rate during weight loss. Sports Med 2006; 36:239-262.
[Figure 1], [Figure 2], [Figure 3]
[Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6]