Fasting Plasma Ghrelin Concentrations 6 Months after Gastric Bypass are not Determined by Weight Loss or Changes in Insulinemia

Background: Ghrelin is a gastric peptide with potent orexigenic effects. Circulating ghrelin concentrations are increased in obese subjects, but increase after weight loss. However, in patients undergoing Roux-en-Y gastric bypass (RYGBP), a decrease in ghrelin levels has been reported. The effect of comparable weight loss induced by either adjustable gastric banding (AGB), RYGBP or conventional dietary treatment (Conv) on ghrelinemia was studied. Methods: 24 matched obese male patients in whom similar weight loss had been achieved by either AGB (n=8), RYGBP (n=8) or Conv (n=8) were studied before and 6 months after treatment start. The independence of ghrelin concentrations from body mass index (BMI) and weight loss was further analyzed in a group of patients with total gastrectomy (TtGx, n=6). Results: Comparable weight loss after 6 months exerted significantly different effects on plasma ghrelin concentrations, depending on the procedure applied (AGB: 424.6 ± 32.8 pg/ml; RYGBP: 131.4 ± 13.5; Conv: 457.3 ± 18.7; P<0.001). Without significant differences in body weight and BMI, patients who had undergone the RYGBP exhibited a statistically significant decrease in fasting ghrelin concentrations, while the other two procedures (AGB and Conv) showed a weight loss-induced increase in ghrelin levels. Despite significant differences in BMI between RYGBP and TtGx patients after 6 months (31.9 ± 2.2 vs 22.0 ± 0.7 kg/m², respectively; P<0.05), both groups showed similar ghrelin concentrations. Conclusion: The reduction in circulating ghrelin concentrations in RYGBP patients after 6 months of surgery are not determined by an active weight loss or an improved insulin-sensitivity but rather depend on the surgically-induced bypass of the ghrelin-producing cell population of the fundus.     

The Decrease in Plasma Ghrelin Concentrations following Bariatric Surgery Depends on the Functional Integrity of the Fundus

Background: Gastric bypass surgery, which involves the production of a reduced stomach pouch,has been shown to markedly suppress circulating ghrelin concentrations. Since bypassing the ghrelin-producing cell population may be relevant to the disruption of fundic-derived factors participating in food intake signaling, the effect of weight loss induced by either adjustable gastric banding (AGB), Roux-en-Y gastric bypass (RYGBP) or biliopancreatic diversion (BPD) was studied. Methods: 16 matched obese patients [35.0 + 2.4 years; initial body weight 124.8 ± 5.7 kg; body mass index (BMI) 47.1 ± 2.2 kg/m²] in whom similar weight loss had been achieved by either AGB (n=7), RYGBP (n=6) or BPD (n=3) were studied. Blood was obtained for biochemical and hormonal analyses. Body composition was assessed by air-displacement-plethysmography. Results: Comparable weight loss (AGB: 26.1 ± 5.1 kg; RYGBP: 32.1 ± 5.0; BPD: 31.7 ± 6.1; P=NS) and decrease in percentage body fat (AGB: 10.0 ± 1.5%; RYGBP: 14.2 ± 2.8; BPD: 10.3 ± 1.0; P=NS) induced by bariatric surgery exerted significantly different (P=0.004) effects on plasma ghrelin concentrations, depending on the surgical procedure applied (AGB: 480 ± 78 pg/ml; RYGBP: 117 ± 34; BPD: 406 ± 86). Without significant differences in BMI, body fat, glucose, triglycerides, cholesterol, insulin and leptin levels, patients who had undergone the RYGBP exhibited statistically significant diminished circulating fasting plasma ghrelin concentrations compared with the other two bariatric techniques which conserve direct contact of the fundus with ingested food (P=0.003 vs AGB and P=0.020 vs BPD). Conclusion: Fasting circulating ghrelin concentrations in patients undergoing diverse bariatric operations depend on the degree of dysfunctionality of the fundus.     

Revision of Failed Laparoscopic Adjustable Gastric Banding to Roux-en-Y Gastric Bypass

Background: The most common bariatric surgical operation in Europe, laparoscopic adjustable gastric banding (LAGB), is reported to have a high incidence of long-term complications. Also, insufficient weight loss is reported. We investigated whether revision to Roux-en-Y gastric bypass (RYGBP) is a safe and effective therapy for failed LAGB and for further weight loss. Methods: From Jan 1999 to May 2004, 613 patients underwent LAGB. Of these, 47 underwent later revisional Roux-en-Y gastric bypass (RYGBP). Using a prospectively collected database, we analyzed these revisions. All procedures were done by two surgeons with extensive experience in bariatric surgery. Results: All patients were treated with laparoscopic (n=26) or open (n=21) RYGBP after failed LAGB. Total follow-up after LAGB was 5.5±2.0 years. For the RYGBP, mean operating time was 161±53 minutes, estimated blood loss was 219±329 ml, and hospital stay was 6.7±4.5 days. There has been no mortality. Early complications occurred in 17%. There was only one late complication (2%) – a ventral hernia. The mean BMI prior to any form of bariatric surgery was 49.2±9.3 kg/m², and decreased to 45.8±8.9 kg/m² after LAGB and was again reduced to 37.7±8.7 kg/m² after RYGBP within our follow-up period. Conclusion: Conversion of LAGB to RYGBP is effective to treat complications of LAGB and to further reduce the weight to healthier levels in morbidly obese patients.     

Laparoscopic Conversion of the Gastric Bypass into a Normal Anatomy

Background: Laparoscopic Roux-en-Y gastric bypass (RYGBP) is considered as a non-reversible procedure. We report the laparoscopic conversion of RYGBP into a normal anatomy. Methods: In June 2004, a laparoscopic RYGBP was performed in a 46-year-old female sweet-eater with BMI 46 kg/m². After 7 months, the patient reported a significant and incapacitating dumping syndrome without postprandial hypoglycemia. She requested conversion to a normal anatomy; hence, a laparoscopic RYGBP reversal was performed. The BMI at the time was 27 kg/m². Results: Operative time was 95 minutes and intra-operative blood loss was 150 ml. The patient had an uneventful recovery and was discharged home on the 5th postoperative day. At 6 months follow-up, her BMI was 27 kg/m², and barium swallow showed good passage with good gastric motility. After 1 year, the BMI is still unchanged and she is doing well. Conclusion: Restoration of normal anatomy after RYGBP is feasible.     

Band Erosion after Laparoscopic Gastric Banding: Occurrence and Results after Conversion to Roux-en-Y Gastric Bypass

Background: Laparoscopic adjustable gastric banding is a popular bariatric operation. Unfortunately, long-term complications such as slippage, infection, and intragastric migration (erosion) may occur. With erosion, band removal is mandatory. Options to prevent weight regain are delayed implantation of a new band, or conversion to another bariatric procedure such as Roux-en-Y gastric bypass (RYGBP) or biliopancreatic diversion. We present our experience with band erosion and immediate or delayed conversion to RYGBP. Methods: With a multidisciplinary team approach and prospective data collection, a comparison was made between patients with and without band erosion. The patients who were converted to RYGBP for band erosion were analyzed. Results: Gastric banding was performed on 347 patients between 1995 and 2002. Median follow-up is 52 months. Band erosion developed in 24 patients (6.8 %).The latter were heavier before gastric banding (BMI 45.9 vs 43.3, P <0,01). No band had ever been overinflated. Band erosion was diagnosed after a mean of 22.5 months (3-51). At time of diagnosis, mean BMI of 33.5 kg/m² (22.5-48) and average excess weight loss (EWL) of 52.9% (25-97) did not differ from that of the remaining patients at the respective time interval. The band was removed in all cases. Conversion to RYGBP was performed at the same time in 11, and a few months later in 2 patients. Operative morbidity included 1 leak (reoperation) and 4 wound infections. All but 1 patient lost further weight after reoperation, or at least maintained their weight. At last follow-up, mean EWL in relation to the pre-banding weight was 65.1%, and 69.2% of the patients had an EWL >50%, which compares favorably with the results obtained after primary RYGBP. Conclusions: In our series with a median follow-up >4 years, band erosion was more common than usually reported. Band removal with immediate or delayed conversion to RYGBP is feasible with an acceptable morbidity, and prevents weight regain in most cases. These results support further use of this approach for band erosion.     

Adjustable Gastric Banding as a Revisional Bariatric Procedure after Failed Gastric Bypass

Background: Inadequate weight loss after proximal gastric bypass presents a clinical challenge to bariatric surgeons. Pouch size, stoma size and limb length are the variables that can be surgically altered. Aside from conversion to distal bypass, which may have significant negative nutritional sequelae, revisional surgery for this group of patients has not often been reported. The addition of adjustable silicone gastric banding (ASGB) to Roux-en-Y gastric bypass (RYGBP) may be a useful revision strategy because it has potential safety benefits over other revisional approaches. Materials and Methods: We report on 8 patients who presented with inadequate weight loss or significant weight regain after proximal gastric bypass. All patients underwent revision with the placement of an ASGB around the proximal gastric pouch. Bands were adjusted at 6 weeks postoperatively and beyond as needed. Complications and weight loss at the most recent follow-up visit were evaluated. Results: Mean age and body mass index (BMI) at the time of revision were 39 ± 9.9 years and 44.0 ± 4.5 kg/m² respectively. No patients were lost to follow-up, and they lost an average of 38.1 ± 10.4% and 44.0 ± 36.3% of excess weight and 49.1 ± 20.9% and 52.0 ± 46.0% of excess BMI in 12 and 24 months respectively. Patients lost an average of 62.0 ± 20.5% of excess weight from the combined surgeries in 67 (48–84) months. The only complication was the development of a seroma overlying the area of the port adjustment in one patient. There have been no erosions or band slippages to date. Conclusions: These results indicate that the addition of an ASGB causes significant weight loss in patients with poor weight loss outcome after RYGBP. The fact that no anastomosis or change in absorption is required may make this an attractive revisional strategy. Long- term evaluation in a larger population is warranted.     

Concurrent Gastric Bypass and Repair of Anterior Abdominal Wall Hernias

Background: Many patients seeking surgical treatment for morbid obesity present with anterior abdominal wall hernias. Although principles of hernia repair involve a tension-free repair with the use of prosthetic mesh, there is concern about the use of mesh in gastric bypass surgery due to potential contamination with the contents of the gastrointestinal tract and resultant mesh infection. We report our series of patients undergoing Roux-en-Y gastric bypass (RYGBP) and simultaneous anterior abdominal wall hernia repair. Methods: All patients who underwent simultaneous RYGBP surgery and anterior abdominal wall hernia repair were reviewed. Results: 12 patients underwent concurrent RYGBP and anterior wall hernia repair. There were 5 women and 7 men with average age 54.9 ± 8.5 years (range 35 to 64) and average body mass index (BMI) 50.4 ± 10.3 kg/m² (range 38 to 70). Two open and 10 laparoscopic RYGBP operations were performed. Nine patients (75%) underwent incisional hernia repairs and 3 patients (25%) underwent umbilical hernia repair concurrent with gastric bypass. Average size of defect was 14.7 ± 13.4 cm². One patient had primary repair and 11 patients had prosthetic mesh repair: polypropylene in 3 patients (25%) and polyester in 8 patients (67%). With a 14.1 ± 9.3 month follow-up, there have been no mesh infections and 2 recurrences, one in the patient who underwent primary repair and one in a patient repaired with polyester mesh but with two previous failed incisional hernia repairs. Conclusion: Concurrent RYGBP and repair of anterior abdominal wall hernias is safe and feasible. In order to optimize success, tension-free principles of hernia repair with the use of prosthetic mesh should be followed since no mesh infections occurred in our series.     

Incidence of Regurgitation after the Banded Gastric Bypass

Background: Frequent regurgitation is a common complication following Roux-en-Y gastric bypass (RYGBP). This study investigated the risk of becoming a chronic regurgitator, by considering silicone ring size and lower esophageal sphincter (LES) function, and their relationship with weight loss. Methods: 80 morbidly obese patients were randomly selected to undergo surgery using ring length of 62 mm (40 patients, group A) or 77 mm (40 patients, group B), with 6 months' postoperative follow-up. Preoperative esophageal manometry parameters were correlated with occurrence of chronic postoperative regurgitation. Patients were considered to present chronic regurgitation when this occurred on >10 days/month. Results: The groups were homogeneous regarding age, gender, race, weight, BMI (47.8±6.1 vs 50.2±6.4 kg/m²) and obesity-related diseases. There were 15% more chronic regurgitators in group A than in group B. Chronic regurgitators in group A lost more weight than chronic regurgitators in group B (P=0.026) or non-chronic regurgitators in group A (P=0.016). A greater proportion of chronic regurgitators had LES hypotonia (mean respiratory pressure <14 mmHg) than did non-chronic regurgitators (P=0.008). Logistic regression demonstrated that the chance of being a chronic regurgitator in group A was 4.5 times greater than in group B (P=0.046), and that the chance of a chronic regurgitator having LES hypotonia was seven times greater than of having normal LES pressure (P=0.006). Conclusion: Silicone ring size and LES hypotonia are independent prognostic factors for chronic regurgitation following RYGBP. Ring size and chronic regurgitation contribute significantly towards weight loss during the first 6 postoperative months.     

Intragastric Stimulation is Ineffective after Failed Adjustable Gastric Banding

Background: Gastric pacing has gained popularity as an effective and safe minimally invasive procedure to treat morbid obesity. This study evaluates the outcome of gastric pacing as a bariatric re-do procedure in patients who developed failure after adjustable gastric banding (AGB) due to band migration. Methods: 8 patients were enrolled in this analysis. After implantation of an AGB, they had developed band failure due to band migration. The implantable gastric stimulator (IGS) was implanted laparoscopically as a second-line operation after gastroscopic removal of the band. Results: Median time (range) from AGB complication to implantation of the IGS was 42 (10.3-50.3) months. During that time, all 8 patients had regained significant weight. All IGS devices could be implanted laparoscopically, without intra- or perioperative complications. The minimal body weight following IGS implantation was reached after 5 (0-12) months. The median observation time was 23 (11.3-27.5) months. 1 year after IGS implantation (n=7), median weight was 116 (98-165) kg, equivalent to a median BMI of 41.1 (36.055.8) kg/m², which is not statistically different to preoperative values and therefore prompted us to stop our ongoing trial. In all but 2 patients, the IGS device was explanted. During the same procedure, patients underwent a gastric sleeve resection (n=4) or a Roux-en-Y gastric bypass (n=2). Conclusion: The implantation of an IGS was an ineffective second-line operation after AGB migration.     

Prevalence of Subclinical Hypothyroidism in a Morbidly Obese Population and Improvement after Weight Loss Induced by Roux-en-Y Gastric Bypass

Background:There are many studies concerning thyroid function in obesity, and some of them describe higher TSH levels in obese subjects. Few studies evaluated long-term changes in thyroid function caused by weight loss after bariatric surgery. Our aims were to evaluate the prevalence of subclinical hypothyroidism (SH) in a morbidly obese population and to analyze the effect of weight loss induced by Roux-en-Y gastric bypass (RYGBP) on TSH and thyroid hormone (TH) levels. Methods: TSH, free thyroxine (fT4) and total triiodothyronine (T3) levels were analyzed before and 12 months after RYGBP in patients with grade III or grade II obesity with co-morbidities. Subjects taking TH and/or with positive antithyroid antibodies and/or with overt hypothyroidism were excluded. Results: 72 subjects (62F/10M), with mean age 39.6±9.8 years and mean BMI 53.0±10.4 kg/m² were studied. The prevalence of SH before RYGBP was 25% (n=18). There was a significant post-surgical decrease in BMI in the whole population, as well as in SH patients. In the SH group and normal TSH group, there was a decrease in TSH and T3, but not in fT4. TSH was not correlated with initial BMI or percent change in BMI. TSH concentrations reached normal values in all SH patients after RYGBP. Conclusion: Our data confirm that severe obesity is associated with increased TSH. The decrease in TSH was independent of BMI, but occurred in all SH patients. A putative effect of weight reduction on the improvement of SH in all patients may be an additional benefit of bariatric surgery.     

The Proximal Gastric Pouch Invariably Contains Acid-Producing Parietal Cells in Roux-en-Y Gastric Bypass

Background: Roux-en-Y gastric bypass (RYGBP) is well tolerated and effective in ameliorating diseases common to morbidly obese patients. A potential drawback, however, is the risk for stomal ulcers, probably due to acid and peptic digestion of the mucosa in the proximal Roux limb. Methods: In 23 RYGBP patients (mean BMI 45 kg/m², age 39 years), the gastro-jejunostomy was performed by circular stapler and the gastric suture ring retrieved for histological examination. 13 consecutive patients received our standard totally transected 4 × 3 cm proximal gastric pouch. The anvil was passed transgastricly and reference biopsies were taken from the gastrotomy in the corpus of the stomach. In the last 10 patients, the pouch size was reduced to 2 × 3 cm by a modified surgical technique. Results: All suture rings from the standard pouches consisted of corpus-fundus mucosa with a large amount of parietal cells, histologically identical to the reference biopsies from the gastrotomy. Also, the 10 suture rings from the modified small pouches contained corpus-fundus mucosa. In 5 of these samples, cardiac mucosa was found, but only in a small segment (6 mm). In addition, 3 patients had esophageal epithelium in the suture ring. Conclusion: The proximal pouch invariably contains acid-producing parietal cells. In order to reduce acid production and, hence, the risk of stomal ulcers, the pouch has to be made as small as possible.     

Severe Protein-Calorie Malnutrition after Bariatric Procedures

Background: Serious nutritional complications after Roux-en-Y gastric bypass (RYGBP) are infrequent. In a retrospective study of patients operated during a 68-month period, malnutrition was investigated to analyze circumstances associated with nutritional failure. Methods: In 236 consecutive RYGBPs, 11 patients with severe malnutrition were identified (4.7%) with age 45.1 ± 10.6 years (10 females/1 male) and initial BMI 54.6 ± 8.4 kg/m². Results: In these 11 patients, the derangement was diagnosed 17.9 ± 15.8 months after RYGBP, following defined events in 63.6% (gastric stenosis, associated diseases ) or mostly exaggeration of expected symptoms in 36.4% (vomiting without endoscopic abnormalities). BMI then was 31.4 ± 8.6 kg/m² (42.5 ± 9.9% total reduction, or 2.4 ± 2.1% decrease/month), and serum albumin and hemoglobin were 24.0 ± 8.2 g/L and 97.0 ± 23.0 g/L respectively. Edema was present in 45.4% (5/11), hospitalization was required in 54.5% (6/11), and 18.2% (2/11) eventually died. Conclusions: Serious malnutrition was unusual but not exceedingly rare in this series. Exogenous precipitating factors were clearly identified in 63.6% of the patients. Careful clinical and nutritional follow-up is recommended to prevent these uncommon but potentially dangerous complications.     

Increased Serum Amyloid A Concentrations in Morbid Obesity Decrease after Gastric Bypass

Background: Obesity is considered a state of low-grade chronic inflammation, which may favor the development of cardiovascular diseases. Serum amyloid A (SAA) is an acute phase protein synthesized in response to infection, inflammation, injury, and stress. The aim of the present study was to compare the circulating concentrations of SAA and the mRNA expression in omental adipose tissue between lean and obese individuals and to analyze the effect of weight loss after gastric bypass. Methods: 16 lean volunteers (BMI 20.5 ± 0.6 kg/m²) and 24 obese patients (BMI 47.0 ± 1.2 kg/m²) were included in the study. Serum concentrations of SAA were measured by ELISA. In addition, the concentrations of SAA in 18 morbidly obese patients (7 male/11 female; BMI 44.6 ± 1.9 kg/m²) were measured before and after weight loss following Roux-en-Y gastric bypass (RYGBP). SAA expression in omental adipose tissue was quantified by RT-PCR in biopsies from obese patients undergoing RYGBP and from age-matched lean individuals subjected to Nissen fundoplication. Results: Obese patients exhibited significantly increased circulating SAA concentrations (6.6 ± 0.5 vs 39.3 ± 9.1 μg/ml; P<0.01) compared to lean subjects. A significant positive correlation was found between logSAA and body fat (r=0.631, P<0.0001). Obese patients showed significantly increased (P<0.05) mRNA expression of SAA in omental adipose tissue compared to lean subjects. Weight loss significantly decreased SAA concentrations after RYGBP (final BMI 28.5 ± 0.9 kg/m², P<0.0001 vs initial) from 47.5 ± 14.5 to 15.7 ± 2.9 μg/ml (P<0.05). Conclusion: It can be concluded that serum SAA and mRNA expression of SAA in omental adipose tissue are increased in obese patients contributing to the obesity-associated cardiovascular disease risk. Moreover, weight loss reduces SAA concentrations, which may contribute to the beneficial effects accompanying weight reduction.     

Pre- and Post-prandial Plasma Ghrelin Levels Do Not Correlate with Satiety or Failure to Achieve a Successful Outcome after Roux-en-Y Gastric Bypass

Background: We tested the hypothesis that the amount of weight lost after Roux-en-Y gastric bypass (RYGBP) correlates with plasma ghrelin levels. Methods: 36 morbidly obese patients were studied 3 years after RYGBP (6 men, 30 women) with mean initial BMI 51 kg/m² and 8 healthy controls (2 men, 6 women) with mean BMI 25 kg/m². Subjects consumed a light breakfast, and the first blood sample was drawn at 1200 hrs immediately before lunch and the second sample at 1400 hrs. Satiety was assessed using a Visual Analog Scale (VAS). Patients were stratified as success (current BMI <35) or failures (current BMI ≥35). Results: Plasma ghrelin levels were significantly lower in patients after RYGBP (269 ± 66 pcg/ml) compared with lean controls (616 ± 112 pcg/ml, P<0.001). Ghrelin levels pre or post meals were not different between patients who had a successful weight loss (preoperative BMI 47, current BMI 29, 72% EWL) or those who achieved a less then ideal weight loss (preoperative BMI 48, current BMI 41, 29% EWL). There was no correlation between any of the VAS scores and plasma ghrelin. There was a strong inverse correlation between pre-prandial ghrelin levels and the preoperative or current BMI. Conclusion: Failure to lose weight after RYGBP does not correlate with pre- or post-prandial ghrelin plasma levels. Ghrelin levels were inversely proportional to BMI and did not correlate with satiety. These data do not support a role for higher plasma ghrelin levels for inadequate weight loss after RYGBP.     

A biodegradeable membrane from porcine intestinal submucosa to reinforce the gastrojejunostomy in laparoscopic Roux-en-Y gastric bypass: preliminary report

Backround: A Silastic ring has been used to prevent dilation of the gastrojejunostomy in Roux-en-Y gastricbypass (RYGBP). The use of a bio-membrane may prevent dilation of the anastomosis without the risks associated with prostheses. The aim of this studywas to evaluate the feasibility and safety of applying such a bio-mem brane around the gastrojejunostomy junostomy in Laparoscopic RYGBP (LRYGBP). Methods: We used a new bio-membrane, that is dreived from porcine small intestinal submucosa (SIS)and acts as a scaffolding for the ingrowth of connective tissue. Over a 4-month period, 14 LRYGBP patients had their proximal anastom osis wrapped with 10 x 2.5 cm SIS by a single surgeon. We compared these patients to a control group of LRYGBP patients matched for BMI. Results: The average age of the patients was 35.0 years (control group: 45.1 years). The patients had a mean initial BMI of 44.7 kg/m² (±5.9) standard error, and the control subjects had a mean initial BMI of 46.7 kg/m² (±6.5). SIS application took a mean time of 11 (±3) minutes without any intraoperative complication. The median hospital stay was 3.5 days in the experimental group and 3.7 days in controls. Three patients developed a symptomatic stenosis at the gastrojejunostomy following surgery. In the control group there were two stenoses. At an average follow-up of 87 days (controls: 95 days), the mean reduction in BMI was 7.8 (± 0.8) kg/m² [controls 8.6 kg/m² (± 1.5)]. Conclusion: Application of SIS around the gastrojejunostomy in patients undergoing LRYGBP is feasible and safe. Further follow-up is required, however, to evaluate the effectiveness in preventing dilation of the anastomosis.     

A Prospective Comparison of Vertical Banded Gastroplasty and Roux-en-Y Gastric Bypass in a Non-Superobese Population

Background: In the non-superobese population, consensus is currently unavailable in bariatric surgery. We report the results of a prospective comparison of vertical banded gastroplasty (VBG) and Roux-en-Y gastric bypass (RYGBP) in a non-superobese population. Methods: From 1994 to 2000, 179 patients with clinically severe obesity underwent various surgical procedures in our department. During this time a prospective study was undertaken in order to compare VBG with RYGBP in morbidly obese patients with a BMI <50 kg/m². Based on specific criteria including eating behavior, 68 patients were selected to undergo RYGBP and 35 VBG. All patients have undergone complete follow-up evaluation at 1, 3, 6, and 12 months postoperatively and every year thereafter. Results: All patients have now completed their 5th postoperative year. Mean follow-up period to date is 96.5±12.2 months for VBG and 67.6±11.3 months for RYGBP. 3 patients (8.6%) in the VBG group and 9 patients (13.2%) in the RYGBP group are lost to follow-up. Mean excess weight loss (EWL) was always better in the RYGBP group (P=0.0013). The percentage of failure, defined as EWL <25%, was not significantly different between the two procedures. No statistically significant differences were observed between the 2 groups in the total number of non-metabolic complications, and the only statistically significant difference observed in metabolic complications was vitamin B₁₂ deficiency after RYGBP. Frequency of vomiting was significantly less and quality of eating significantly better in RYGBP than in VBG patients. Conclusion: This prospective long-term study, with nearly complete follow-up, suggests that in the non-superobese population, preoperative eating habits may play a role in choosing the most appropriate bariatric operation for each patient. Although RYGBP is associated with better mean weight loss outcomes, the percentage of patients who achieved and maintained ≥50% EWL after VBG in this pre-selected patient population was not significantly different. Each type of operation has advantages and disadvantages, and, if properly chosen, a purely restrictive procedure can be successful for some patients. Therefore, it can be said that the decision regarding which bariatric procedure to perform in non-superobese patients must be based on in-depth preoperative evaluation as well as the patients' own preferences and outcome expectations.     

Predictors of Weight Status following Laparoscopic Gastric Bypass

Background: Weight loss after bariatric surgery varies and depends on many factors, such as time elapsed since surgery, baseline weight, and co-morbidities. Methods: We analyzed weight data from 494 patients who underwent laparoscopic Roux-en-Y gastric bypass (RYGBP) by one surgeon at an academic institution between June 1999 and December 2004. Linear regression was used to identify factors in predicting % excess weight loss (%EWL) at 1 year. Results: Mean patient age at time of surgery was 44 ± 9.6 (SD), and the majority were female (83.8%). The baseline prevalence of co-morbidities included 24% for diabetes, 42% for hypertension, and 15% for hypercholesterolemia. Baseline BMI was 51.5 ± 8.5 kg/m². Mean length of hospital stay was 3.8 ± 4.6 days. Mortality rate was 0.6%. Follow-up weight data were available for 90% of patients at 6 months after RYGBP, 90% at 1 year, and 51% at 2 years. Mean %EWL at 1 year was 65 ± 15.2%. The success rate (≥50 %EWL) at 1 year was 85%. Younger age and lower baseline weight predicted greater weight loss. Males lost more weight than females. Diabetes was associated with a lower %EWL. Depression did not significantly predict %EWL. Conclusion: The study demonstrated a 65 %EWL and 85% success rate at 1 year in our bariatric surgery program. Our finding that most pre-surgery co-morbidities and depression did not predict weight loss may have implications for pre-surgery screening.     

Systematic Review of Medium-Term Weight Loss after Bariatric Operations

Background: Although bariatric surgery is known to be effective in the short term, the durability of that effect has not been convincingly demonstrated over the medium term (>3 years) and the long term (>10 years). The authors studied the durability of weight loss after bariatric surgery based on a systematic review of the published literature. Methods: All reports published up to September, 2005 were included if they were full papers in refereed journals published in English, of outcomes after Roux-en-Y gastric bypass (RYGBP), and its hybrid procedures of banded bypass (Banded RYGBP) and longlimb bypass (LL-RYGBP), biliopancreatic diversion with or without duodenal switch (BPD±DS) or laparoscopic adjustable gastric banding (LAGB). All reports that had at least 100 patients at commencement, and provided ≥3 years of follow-up data were included. Results: From a total of 1,703 reports extracted, 43 reports fulfilled the entry criteria (18 RYGBP; 18 LAGB; 7 BPD). Pooled data from all the bariatric operations showed effective and durable weight loss to 10 years. Mean %EWL for standard RYGBP was higher than for LAGB at years 1 and 2 (67 vs 42; 67 vs 53) but not different at 3, 4, 5, 6 or 7 years (62 vs 55; 58 vs 55; 58 vs 55; 53 vs 50; and 55 vs 51). There was 59 %EWL for LAGB at 8 years, and 52 %EWL for RYGBP at 10 years. Both the BPD±DS and the Banded RYGBP appeared to show better weight loss than standard RYGBP and LAGB, but with statistically significant differences present at year 5 alone. The LL-RYGBP was not associated with improved %EWL. Important limitations include lack of data on loss to follow-up, failure to identify numbers of patients measured at each data point and lack of data beyond 10 years. Conclusions: All current bariatric operations lead to major weight loss in the medium term. BPD and Banded RYGBP appear to be more effective than both RYGBP and LAGB which are equal in the medium term.     

Role of Gastric Acid in Stomal Ulcer after Gastric Bypass

Background: The pathogenetic mechanisms of stomal ulcer after Roux-en-Y gastric bypass (RYGBP) are unclear. In order to study the role of gastric acid, we measured acidity in the proximal pouch using a pH-sensitive probe. Methods: 6 patients (5 females, mean age 45 years old at time of operation) with endoscopically confirmed stomal ulcer, were studied 2 to 6 years after RYGBP. All complained of epigastric pain that improved during proton pump inhibitor (PPI) therapy. Control subjects were 6 females (50 years old) who had had RYGBP at least 5 years earlier and denied symptoms of epigastric pain or heartburn. The pH-sensitive probe (Digitrapper-pH, Medtronic) was passed through the nose to the proximal pouch, guided by the calculated distance and pH response. The probe was left in place for 4 hours. The percentage of time with pH <4 was calculated. Results: The probe could be accurately positioned in the proximal pouch both in symptomatic patients and in controls as evidenced by the acid pH reaction. The proximal pouches of patients with stomal ulcer were significantly more exposed to acid compared to controls. The median percentage of time with pH <4 was 69% and 20% in the stomal ulcer and the control group, respectively (P<0.01). Barium follow-through excluded gastro-gastric fistula in stomal ulcer patients. Conclusion: RYGBP patients with stomal ulcer have increased acid production in their proximal pouch in comparison with asymptomatic RYGBP patients. Gastric acid appears to have an important role in the pathogenesis of stomal ulcer.     

Changes in Insulin Sensitivity in Morbidly Obese Patients with or without Metabolic Syndrome after Gastric Bypass

Background: We evaluated the medium term changes in insulin sensitivity in morbidly obese patients with and without metabolic syndrome before and after Roux-en-Y gastric bypass (RYGBP) with silastic ring (Capella-Fobi). Methods: A longitudinal, clinical intervention study was conducted in 40 patients between 18 and 65 years old, with obesity class II and III (BMI ≥35-52 kg/m²), divided into 2 groups: no metabolic syndrome (NMS, n=21) and metabolic syndrome (MS, n=19). Anthropometric measurements, biochemical tests and classification of MS according to the NCEP criteria, were performed pre-operatively and at 3 and 6 months postoperatively. Results: In the preoperative period, 87% of the patients presented obesity class III (BMI 47±5 kg/m²) while 13% of the patients had obesity class II (37±2 kg/m²), and 19 patients (47.5%) presented MS. In the preoperative period, there were no differences among patients with MS and NMS in relation to the anthropometrics and body composition measurements. However, triglyceridemia, glycemia and insulinemia were higher in the MS group compared to the NMS group (P<0.05), although there was no difference in HOMA between the groups. HDL-cholesterol was lower in the MS group (p<0.05). In both postoperative study periods, all patients had significant reduction of anthropometric variables, body composition and biochemical variables. There were no differences between MS and NMS (p>0.05) groups. However, insulinemia decreased more in the postoperative period in the MS group compared to the NMS group (p<0.05). MS frequency in the MS group diminished to 26% after 3 postoperative months and no patient presented features of MS after 6 months postoperatively. Conclusions: Based on these observation: 1) patients of class II and III obesity present peripheral resistance to hyperinsulinemia without hyperglycemia; 2) RYGBP is able to reduce anthropometric measurements and body composition in a similar way for patients who have, or have not, MS; 3) there is rapid normalization of biochemistry of carbohydrates and lipids; 4) patients with previous MS lose the criteria needed for this diagnosis after 6 postoperative months.