Laparoscopic Roux-en-Y gastric bypass versus laparoscopic vertical banded gastroplasty: results of a 2-year follow-up study

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

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

Long-Term (over 13 Years) Follow-Up of Vertical Band Gastroplasty

BACKGROUND

Silastic ring vertical gastroplasty (SRVG) was a popular restrictive procedure 2 and 3 decades ago. However, it was associated with severe complications and a high rate of reoperation due to failure. Examination of long-term outcomes of those patients that underwent SVRG is limited. The aim of our study was to determine the long-term outcomes (over 13 years) of SRVG in our institution and to review the literature of long-term outcomes following SVRG.

METHODS

Following IRB approval, we reviewed patients who underwent SRVG between 1996 and 2001. Weight loss parameters, preoperative comorbidities, were compared to the follow-up data.

RESULTS

In total, 92 patients underwent SRVG, and 89 met the inclusion criteria. Mean age was 52.4 ± 10.6 years and body mass index (BMI) was 46.1 ± 6.5 Kg/m². Preoperative comorbidities rate included diabetes mellitus (19.1%), hypertension (32.5%), hyperlipidemia (21.3%), joints disease (6.7%), mood disorders (7.8%), and dyspeptic disorders (3.3%). Mean length of follow-up was 208.5 ± 16.8 months. Thirty-eight patients (43%) had to be reoperated due to complications and 24 (30%) had an additional bariatric surgery. Follow-up BMI was 34.2 ± 9.8 Kg/m² (p < 0.001). There was no improvement in any of the comorbidities; incidence of joint disease and dyspeptic disorders were significantly higher at the follow-up (p = 0.03, p < 0.001, respectively).

CONCLUSIONS

SRVG procedure was associated with high rates of reoperations and revisions. The majority of our patients showed poor resolution of comorbidities and even worsening of some. Our data confirms that SRVG is not suitable as a bariatric procedure.

Bacterial Lipopolysaccharide, Lipopolysaccharide-Binding Protein, and Other Inflammatory Markers in Obesity and After Bariatric Surgery

Obesity is associated with altered gut microbiota and low-grade inflammation. A key factor in the inflammatory process is endotoxin lipopolysaccharide (LPS). Plasma LPS levels and sensory agent lipopolysaccharide-binding protein (LBP) are shown to be elevated in obesity. This elevation may be due to increased intestinal permeability and incorporation of a high-fat diet accompanied by overfeeding. Bariatric surgery has become a popular treatment option that results in stable weight loss and improvement of obesity-related conditions. Studies outlined in this review show reduced LPS and LBP levels after different bariatric procedures. LPS receptor CD14 and mRNA expression toll-like receptor 2 (TLR2) and toll-like receptor 4 (TLR4) were also shown to have reduced levels following surgery. Changes in LPS and LPS components after bariatric surgery are shown to be linked to the surgical technique of the procedure and restriction of caloric intake. Additionally, changes in the gut microbiota provide some insight to the reduction of inflammatory markers after surgery. The beneficial effects of bariatric surgery are not dependent on weight loss alone. The inflammatory pathway plays a key role in the improvement of metabolic complications following surgery that should be further examined. Additional research is needed to evaluate short- and long-term changes of LPS and LPS components after bariatric surgery, including how those assessments can be applied to clinical practice.

Long-term effects of bariatric surgery on type II diabetes, hypertension and hyperlipidemia: a meta-analysis and meta-regression study with 5-year follow-up

BACKGROUND

The first aim of the study was to estimate weight loss and major modifiable risk factors after bariatric surgery. The second aim was to investigate the relationship between the reduction in cardiovascular risk and weight loss over time.

METHODS

A random effect of meta-analysis and dose-response meta-regression was used to evaluate weight loss and the risk of type II diabetes, hypertension and hyperlipidemia, 2-5 years after surgery.

RESULTS

A search of the literature led to the selection of 22 papers. The body mass index (BMI) at the end of the observation period was 31.7 (95 % CI = 29.7-33.7; I(2) = 6 %). The risk of type II diabetes, hypertension and hyperlipidemia decreased after bariatric surgery, with relative risks of, respectively, 0.33 (95 % CI = 0.26-0.41; I(2) = 42 %), 0.54 (95 % CI = 0.46-0.64; I(2) = 68 %) and 0.33 (95 % CI = 0.22-0.46; I(2) = 74 %). Nonlinear meta-regression revealed different patterns of risk: Hypertension risk reached a minimum when the BMI fell 10 units. The risks of all cardiovascular outcomes reached a plateau, 20-40 months after surgery.

CONCLUSIONS

The reduction in arterial hypertension reached a nadir earlier than the risk of diabetes and hyperlipidemia, thus indicating a possible link between weight reduction and positive hemodynamic effects.

15-year follow-up of vertical banded gastroplasty: comparison with other restrictive procedures

INTRODUCTION

Vertical banded gastroplasty (VBG) has been the procedure of choice for bariatric surgeries since the 1980s. However, long-term results of VBG have been reported with different opinions, and new restrictive procedures have been innovated and showing variable results. The aim of this study is to analyze the long-term results of our VBG patients.

PATIENT AND METHODS

Between June 1998 and May 2002, 652 morbidly obese patients received VBG, with the initial 40 patients having open procedures and the subsequent 612 patients using a laparoscopic approach. Operative complications, weight loss, and late complications were followed and compared with groups of laparoscopic adjustable gastric banding (LAGB) and sleeve gastrectomy (LSG).

RESULTS

Mean age, preoperative weight, and body mass index (BMI) were 30.96 years, 108.83 kg, and 40.63 kg/m(2), respectively. The overall early postoperative complication rate was 3.4% (22/652). The excess weight loss percentages at 1, 2, 5, and 10 years were 61.04, 59.70, 51.11, and 42.0%, respectively. BMI at 1, 2, 5, and 10 years were 29.64, 29.71, 31.33, and 31.73 kg/m(2), respectively. This result is inferior to the 67% excess weight loss in the LSG group, but is higher than the 38% excess weight loss of the LAGB group. The revision rate is 13.19% (86/652) up to now. Revision surgery was required in 28 (14.0%) patients in the LAGB group and 8 (1.3%) in the LSG group.

CONCLUSION

VBG was an operation with acceptable outcome for treating morbid obesity and metabolic disorders. It sets a standard for new restrictive procedures.

Laparoscopic Magenstrasse and Mill gastroplasty. First results of a prospective study

BACKGROUND

The Magenstrasse and Mill (M&M) procedure is a vertical gastroplasty creating a tubular pouch extending from the cardia to the antrum. This "incomplete sleeve" avoids gastric resection or band placement. In this paper, we report our experience of the laparoscopic approach of the technique in a selected obese population excluding prominent grazer and/or sweet eaters.

MATERIAL AND METHODS

One hundred patients (39 males, 61 females) underwent the procedure in a prospective trial. Mean age was 40 years (range 18-68). Mean preoperative BMI was 43.2 kg/m(2) (range 35-62).

RESULTS

The procedure was performed by laparoscopy starting with the creation of a circular opening at the junction of antrum and corpus followed by a vertical stapling to the angle of Hiss. Mean duration of the procedure was 67 (range 40-122) min. No intraoperative complication occurred. Mean hospital stay (SD) was 2.5 (0.9) days. The single postoperative complication consisted in a mild stenosis that responded to endoscopic dilatation. After a mean follow-up of 15 months (range 9-24), mean percentage of excess body weight loss (SD) was 48(14), 59(18) and 68(24)%, respectively at 3, 6, and 12 months. Quality of life appeared satisfactory with a low incidence of gastroesophageal reflux. The procedure was associated with improvement or resolution of diabetes, arterial hypertension, and dyslipemia at 1 year.

CONCLUSIONS

Our experience demonstrated that the M&M procedure could be performed safely laparoscopically. The satisfactory results on weight loss, obesity-associated mordities, and quality of life will need to be confirmed on longer follow-up.

Effect of Bariatric Surgery on Hypertension

Purpose: Obesity is a growing epidemic leading to worldwide public health concerns. Bariatric surgery is an option for patients with a body mass index (BMI) >40 kg/m2 or BMI of >35 kg/m2 with serious comorbid conditions. This meta-analysis examines the effect of bariatric surgery on the improvement or resolution of hypertension. Methods: Two independent investigators conducted a literature search of PubMed (1990-2013) and Cochrane databases using the terms bariatric surgery and hypertension to identify appropriate human adult studies published in English. Studies were included if they reported the number of patients with hypertension prior to undergoing any bariatric surgery procedure and whether the hypertension improved or resolved postsurgery. The number of patients with hypertension and their response rates were extracted and analyzed using RevMan 5.2.5. Results: In all, 31 prospective and 26 retrospective studies met all criteria. The types of bariatric surgery performed included Roux-en-Y, gastric banding, laparoscopic adjustable gastric banding, vertical gastric banding, sleeve gastrectomy, duodenal switch, and biliopancreatic diversion. The time to first follow-up after surgery varied from 1 week to 7 years. Of the 57 studies, 32 reported improvement of hypertension in 32 628 of 51 241 patients (odds ratio [OR] = 13.24; 95% CI = 7.73, 22.68; P < 0.00001); 46 studies reported the resolution of hypertension in 24 902 of 49 844 patients (OR = 1.70; 95% CI = 1.13, 2.58; P = 0.01). A random-effects model was used because the heterogeneity between the studies was high ( I2 = 97%). Conclusion: The results of this meta-analysis indicate that patients who undergo bariatric surgery experience improvement and resolution of their hypertension.

Rejecting the demise of vertical-banded gastroplasty: a long-term single-institute experience

Surgical interventions have proven to be more effective than other measures in the treatment of morbid obesity. The short-term outcomes of the various surgical interventions have been well documented in the literature, with fewer reports on long-term outcomes. The reported long-term outcome of the vertical-banded gastroplasty (VBG) is conflicting. The aim of the present study was to evaluate our long-term experience with VBG. A retrospective review of a prospectively maintained database was conducted. Records of patients who underwent VBG five or more years ago were retrieved. An analysis of the long-term weight changes and reported complications was conducted. The study included 150 patients: 43 males (29%) and 107 females (71%). Their mean age was 30 years old (12-53), and the mean body mass index (BMI) was 47 ± 8.4 kg/m2. Patients were followed up for an average of 8 years (5-11). More than 60 % of patients had good long-term weight loss (EWL > 50%). A significant negative correlation was found between the excess weight loss percent (EWL%) and the pre-operative BMI (p < 0.05). The differences in EWL% between males and females were not significant (p = 0.061). Nevertheless, the change in EWL% over time for both males and females was significant (p = 0.004). Revision surgery was required in seven patients (4.7%). Five patients had conversion of VBG to gastric bypass (3.3%), while two patients (1.3%) had reversal of the procedure. Late complications included mesh erosion in three cases, staple line dehiscence in two patients, and stomal stenosis in six patients. VBG could be a long-term effective intervention for the treatment of morbid obesity. Good selection is the cornerstone for long-term success. Late complication rate is acceptable after VBG. VBG is a specifically useful tool under stringent financial circumstances.

Effect of bariatric surgery on cardiovascular risk profile

Obesity is associated with increased risk for cardiovascular (CV) disease (CVD) and CV mortality. Bariatric surgery has been shown to resolve or improve CVD risk factors, to varying degrees. The objective of this systematic review was to determine the impact of bariatric surgery on CV risk factors and mortality. A systematic review of the published research was performed to evaluate evidence regarding CV outcomes in morbidly obese bariatric patients. Two major databases (PubMed and the Cochrane Library) were searched. The review included all original reports reporting outcomes after bariatric surgery, published in English, from January 1950 to July 2010. In total, 637 studies were identified from the initial screen. After applying inclusion and exclusion criteria, 52 studies involving 16,867 patients were included (mean age 42 years, 78% women). The baseline prevalence of hypertension, diabetes, and dyslipidemia was 49%, 28%, and 46%, respectively. Mean follow-up was 34 months (range 3 to 155), and the average excess weight loss was 52% (range 16% to 87%). Most studies reported significant decreases postoperatively in the prevalence of CV risk factors, including hypertension, diabetes, and dyslipidemia. Mean systolic pressure reduced from to 139 to 124 mm Hg and diastolic pressure from 87 to 77 mm Hg. C-reactive protein decreased, endothelial function improved, and a 40% relative risk reduction for 10-year coronary heart disease risk was observed, as determined by the Framingham risk score. In conclusion, this review highlights the benefits of bariatric surgery in reducing or eliminating risk factors for CVD. It provides further evidence to support surgical treatment of obesity to achieve CVD risk reduction.

10-year follow-up of laparoscopic vertical banded gastroplasty: good results in selected patients

OBJECTIVE

To evaluate the long-term results of laparoscopic vertical banded gastroplasty (VBG) for morbid obesity.

BACKGROUND

Laparoscopic VBG, a safe and straightforward bariatric procedure characterized by good short-term results, has been progressively replaced by other more complex procedures on the basis of a presumed high rate of long-term failure. Nevertheless, some authors have recently reported long-term efficacy in selected patients.

METHODS

All patients who underwent laparoscopic VBG were included in a prospective database. Patients reaching 10-year follow-up received a complete evaluation including clinical, endoscopic, and biochemical examinations.

RESULTS

Between January 1996 and March 1999, 266 morbidly obese patients underwent bariatric procedures. Among them, 213 were selected for laparoscopic VBG; exclusion criteria were as follows: contraindications to pneumoperitoneum, gastroesophageal reflux disease, and psychological contraindications to restrictive procedures. Mean age, preoperative weight, and body mass index were 36.9 years, 123.6 kg, and 45.4 kg/m, respectively. Intraoperative complication rate and conversion rate were 0.9% and 0.9%, respectively. Early postoperative complication rate was 4.2% and early reoperation rate was 0.5%. Mean hospital length of stay was 6.3 days. Mortality was nil. The 10-year follow-up rate was 70.4% (150 patients). Late postoperative complication rate was 14.7%, and 10-year revisional surgery rate was 10.0%. The excess weight loss percentages at 3, 5, and 10 years were 65.0%, 59.9%, and 59.8%, respectively. The resolution and/or improvement rate for comorbidity were 47.5% for hypertension, 55.6% for diabetes, 75% for sleep apnea, and 47.4% for arthritis. Mean Moorehead-Ardelt Quality of Life Questionnaire and BAROS values were 1.4 and 3.8, respectively.

CONCLUSIONS

The present study demonstrates that laparoscopic VBG in carefully selected patients leads to long-term results comparable with more complex and invasive procedures. Given the low postoperative morbidity for laparoscopic VBG, its present clinical role should be, in our opinion, reevaluated.

Age and gender exert differential effects on blood lipids in patients after LAGB and LRYGB

BACKGROUND

Although bariatric surgery is known to exert favorable effects on dyslipidemia, few studies have systematically considered how the demographic variables might modulate the outcomes. The aim of the present study was to examine the interactive effects of gender, age, and surgery type on dyslipidimia in bariatric surgery patients at a tertiary hospital in the United States.

METHODS

In a retrospective review of 294 patients who had undergone laparoscopic Roux-en-Y gastric bypass (LRYGB) or laparoscopic adjustable gastric bypass (LAGB), we examined the changes in lipid profiles and antihyperlipidemic use for ≤4 years postoperatively. The data were analyzed using longitudinal mixed modeling methods, in which the effects on lipid concentrations and medication use were tested in models with gender, surgery type, age, postoperative duration, and all possible interactions entered as factors.

RESULTS

Significant 2-way interactions of surgery type*time were found for total cholesterol and high-density lipoprotein cholesterol, gender*time for high-density lipoprotein cholesterol, and age*time for triglycerides. A 3-way interaction of surgery type*age*time was noted for low-density lipoprotein cholesterol. For older patients, low-density lipoprotein cholesterol was reduced by 20% from baseline in the LRYGB group but did not lessen significantly in the LAGB group. In the younger patients, however, decreases from the preoperative concentrations were not evident in either surgery group. An interaction of surgery type*time on antihyperlipdemic medication use, in which values changed significantly from baseline was found in both groups. However, the pattern in the LRYGB patients opposed that in the LAGB patients.

CONCLUSION

Our results have demonstrated that bariatric surgery imparts a pronounced improvement in the blood lipid profile of recipients; however, these effects might be moderated by other factors, such as age and gender, independently of the baseline weight status of the patients.

Reversible gastric restriction implant: safety and efficacy in a canine model

BACKGROUND

Gastric restrictive procedures are considered effective weight loss treatment for severe obesity. The aim of the study was to evaluate the efficacy and safety of a reversible implant that renders a partial restriction of stomach in a canine model.

METHODS

The device was comprised of two longitudinal parallel non-compressive plates with two C-rings to create a small gastric pouch that opposed gastric distension. Three groups of non-obese mongrel dogs were included: group I (n = 6) underwent surgical implant for 6 weeks, group II (n = 6) underwent surgical implant for 6 weeks, followed by surgical removal of the implant and additional monitoring for 5 weeks, and group III (n = 5) served as sham-operated controls for groups I and II. Food intake and body weight were monitored, and the stomachs were examined histologically postmortem.

RESULTS

The average food intake was significantly decreased by 38.2% in group I as compared to group III throughout the 6 weeks of surgical implant (P < 0.05). The implanted dogs showed a progressive weight loss as compared to sham, which reached 21% by the end of 6 weeks. In group II, after 5 weeks of implant removal, the body weights recovered to approximately 96% of baseline. Histological evidence of the implant site at the gastric walls revealed no significant structural changes, tissue ischemia, hemorrhage, or necrosis.

CONCLUSION

Our results validate the feasibility of a reversible gastric restriction implant in a non-obese canine model, with the potential for achieving significant weight loss within 6 weeks and with no injury to the gastric wall.

Improved heart rate recovery after marked weight loss induced by gastric bypass surgery: two-year follow up in the Utah Obesity Study

BACKGROUND

Obesity is associated with significantly increased cardiovascular mortality that has been attributed, in part, to sympathetic activation. Gastric bypass surgery (GBS) appears to increase long-term survival in the severely obese, but the mechanisms responsible for this increase are still being sought. Heart rate (HR) recovery after exercise reflects the balance of cardiac autonomic input from the sympathetic and parasympathetic systems. Blunted HR recovery is a very powerful predictor of increased mortality, whereas enhanced HR recovery portends a good prognosis.

OBJECTIVE

The purpose of this study was to evaluate the effect of marked weight loss achieved via GBS on HR recovery.

METHODS

Severely obese patients underwent submaximal exercise testing (80% predicted maximum HR) at baseline and 2 years after GBS (n = 153) or nonsurgical treatment (n = 188).

RESULTS

Patients in the GBS group lost an average of 100 ± 37 lb compared to 3 ± 22 lb in the nonsurgical group (P <.001, GBS vs nonsurgical). Resting HR decreased from 73 bpm to 60 bpm in the GBS group and from 74 bpm to 68 bpm in nonsurgical patients (P <.001). HR recovery improved by 13 bpm in the GBS group but did not change in the nonsurgical group (P <.001 GBS vs nonsurgical). In multivariable analysis, the independent correlates of HR recovery at the 2-year time point were resting HR, treadmill time, age, body mass index, and HOMA-IR (an index of insulin resistance).

CONCLUSION

Marked weight loss 2 years after GBS resulted in a significant decrease in resting HR and an enhancement in HR recovery after exercise. These changes likely are attributable to improvement in insulin sensitivity and cardiac autonomic balance. Whether and to what extent this contributes to a reduction in cardiovascular mortality with GBS remains to be determined.

Lifestyle intervention favorably affects weight loss and maintenance following obesity surgery

The present study was designed to evaluate the 3 year effects of a lifestyle intervention on weight loss and maintenance, dietary, and physical activity habits and eating behavior of patients following vertical banded gastroplasty (VBG). Thirty severely obese female volunteers were included in the study and they were randomly assigned to one of two intervention groups: usual care (UC) or lifestyle intervention (LS) group. Patients were followed for 3 years postoperatively. Outcome measures included weight loss, dietary habits, physical activity level (PAL), and eating behavior changes. Weight was significantly lower in the LS group after 12 months (84.4 +/- 3.9 kg vs. 98.4 +/- 4.4 kg, P < 0.05), 24 months (83.0 +/- 3.3 vs. 101.9 +/- 5.3 kg, P < 0.05), and 36 months following surgery (84.2 +/- 3.3 vs. 102.5 +/- 3.5 kg, P < 0.05). Repeated measures ANOVA revealed significant differences between the two groups overall and at specific time points for the PAL and TV viewing. With regard to eating behavior, the LS group scored significantly better in total Dutch Eating Behavior Questionnaire (DEBQ), Restraint Eating and External Eating scales at all postoperative time points. Similarly, significant differences were found between the two groups in dietary intake. These findings outline the importance of lifestyle intervention on weight loss and maintenance following bariatric surgery. The favorable effects of lifestyle intervention may be through adoption of healthier eating behaviors and increased physical activity.

The effect of intragastric balloon on plasma ghrelin, leptin, and adiponectin levels in patients with morbid obesity

CONTEXT

Ghrelin and leptin are hormones regulating appetite and metabolic processes. Adiponectin plays an important role in the modulation of glucose and lipid metabolism.

OBJECTIVE

The objective of the study was to evaluate the levels of plasma ghrelin, leptin, and adiponectin in obese subjects treated with bioenterics intragastric balloon (BIB), low-calorie diet (1500 kcal), and physical exercise.

DESIGN

BIB was placed for 6 months in 21 subjects with body mass index 47.3 +/- 5.7. The control group consisted of 15 morbidly obese subjects treated with a low-calorie diet and physical effort. Plasma hormone levels were determined by RIA.

RESULTS

In the BIB group, the insertion of the balloon caused a considerable reduction in body mass over a 6-month period (17.1 +/- 8.0 kg) as compared with the control group (3.2 +/- 6.4 kg). After 1 month, the levels of ghrelin increased from 621.9 +/- 182.4 to 903.9 +/- 237 pg/ml and thereafter gradually decreased, reaching the starting level 3 months after the removal of the balloon. In the same group, the levels of leptin decreased from 61.3 +/- 36.7 to 39.9 +/- 17.5 ng/ml. In the control group, the corresponding levels of ghrelin and leptin remained relatively stable. During the observation period, in the BIB group, the levels of adiponectin remained unchanged as opposed to a transient increase noted in the control group.

CONCLUSIONS

In patients with morbid obesity, weight loss induced by BIB is associated with a decrease in plasma leptin and a transient elevation of plasma ghrelin. It is likely that the changes in hormones regulating the energy balance caused by BIB can prevent an increase in adiponectin level.

Adolescent obesity and bariatric surgery

PURPOSE OF REVIEW

Examines the effects of bariatric surgery on adolescent obesity.

RECENT FINDINGS

The risks and outcomes of bariatric surgery in adolescence are presently being defined and may be somewhat different from those in adults. Adolescents may have a greater risk of weight regain, and greater risk of noncompliance to treatment after surgery. However, long-term outcomes are not yet available, and the underlying metabolic benefits appear to be substantial and similar to those of adults.

SUMMARY

Morbid obesity in adolescents has severe acute and chronic complications. Bariatric surgery in adolescents seems as well tolerated as in adults when performed in centers with appropriate experience and adequate surgical volume. The pathophysiologic implications of bariatric surgery are profound. A better understanding of the mechanisms leading to postsurgical improvement in insulin resistance and weight loss could lead to the development of other therapies to achieve the same effects with lesser morbidities.

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

OBJECTIVE

Roux-en-Y gastric bypass (RYGB) produces rapid and dramatic weight loss in very heavy obese patients. Up to 20% cannot sustain their weight loss beyond 2 to 3 y after surgery.

METHODS

To identify putative etiologic factors producing post-RYGB weight regain, a literature survey of metabolic changes in very obese and a review of our diet-induced obese RYGB rat model data was done.

RESULTS

Weight regain suggests an imbalance in physiologic mechanisms regulating appetite and metabolic rate. Weight regain occurred in 25% of our rats, produced by return to presurgical energy intake levels. The 75% of rats that sustained weight loss secreted a significantly larger amount of peptide YY (PYY) while suppressing leptin secretion; those that failed were unable to develop or sustain a sufficiently large plasma PYY:leptin ratio. Metabolic consequences of this failure included reversal of initial postsurgical increases in peripheral fatty acid oxidation, anorexigenic activity in the hypothalamic arcuate nucleus and paraventricular nucleus, and the expression of uncoupling protein-2 in adipose tissues, and decreases in hepatic lipogenesis, free tri-iodothyronine secretion, expression of orexigenic activity in the arcuate nucleus and paraventricular nucleus, expression of adenosine monophosphate kinase in adipose tissues, skeletal muscle mitochondrial mass, and endocannabinoid content and appetite.

CONCLUSION

Weight regain after RYGB occurs in approximately 20% of patients and constitutes a serious complication. Weight regain-promoting consequences are attributed to a failure to sustain elevated plasma PYY concentrations, indicating that combining RYGB with pharmacologic stimulation of PYY secretion in patients after RYGB who exhibit inadequate PYY concentration may increase long-term success of surgical weight reduction in morbidly obese adults.

Clinical application of laparoscopic bariatric surgery: an evidence-based review

BACKGROUND

Approximately one-third of U.S. adults are obese. Current evidence suggests that surgical therapies offer the morbidly obese the best hope for substantial and sustainable weight loss, with a resultant reduction in morbidity and mortality. Minimally invasive methods have altered the demand for bariatric procedures. However, no evidence-based clinical reviews yet exist to guide patients and surgeons in selecting the bariatric operation most applicable to a given situation.

METHODS

This evidenced-based review is presented in conjunction with a clinical practice guideline developed by the Society of American Gastrointestinal and Endoscopic Surgeons (SAGES). References were reviewed by the authors and graded as to the level of evidence. Recommendations were developed and qualified by the level of supporting evidence available at the time of the associated SAGES guideline publication. The guideline also was reviewed and co-endorsed by the American Society for Metabolic and Bariatric Surgery.

RESULTS

Bariatric surgery is the most effective treatment for severe obesity, producing durable weight loss, improvement of comorbid conditions, and longer life. Patient selection algorithms should favor individual risk-benefit considerations over traditional anthropometric and demographic limits. Bariatric care should be delivered within credentialed multidisciplinary systems. Roux-en-Y gastric bypass (RGB), adjustable gastric banding (AGB), and biliopancreatic diversion with duodenal switch (BPD + DS) are validated procedures that may be performed laparoscopically. Laparoscopic sleeve gastrectomy (LSG) also is a promising procedure. Comparative data find that procedures with more dramatic clinical benefits carry greater risks, and those offering greater safety and flexibility are associated with less reliable efficacy.

CONCLUSIONS

Laparoscopic RGB, AGB, BPD + DS, and primary LSG have been proved effective. Currently, the choice of operation should be driven by patient and surgeon preferences, as well as by considerations regarding the relative importance placed on discrete outcomes.