Bariatric Surgery Reverses Natural Killer (NK) Cell Activity and NK-Related Cytokine Synthesis Impairment Induced by Morbid Obesity

Background Obesity is related to a higher rate of infections and some types of cancer. Here we analyzed the impact of obesity and weight loss induced by Roux-en-Y gastric bypass (RYGB) on immunological parameters, i.e., cytokine productions and natural killer cell function. Methods We analyzed 28 morbidly obese patients before and 6 months after RYGB. Biochemical parameters were analyzed in plasma. The percent of natural killer (NK) cells, their cytotoxicity, and the production of cytokines by peripheral blood mononuclear cells were analyzed. The percent of NK cells was determined by flow cytometry and cytokine production determined by enzyme-linked immunosorbent assay. NK cytotoxicity was determined by the lactate dehydrogenase release assay. Results The weight loss 6 months following surgery was 35.3 +/- 4.5 kg. RYGB also improves biochemical parameters. No significant difference was found in the percent of NK cells after surgery. We found an increase in the production of interferon-gamma, interleukin (IL)-12 and IL-18, but not in IL-2, 6 months after RYGB. Cytotoxic activity of NK cells was significantly enhanced 6 months after RYGB [17.1 +/- 14.7% before RYGB vs 51.8 +/- 11.3% at 6 months after, at 40: 1 effector to target cell ratio; p<0.001]. We observed significant post-surgical improvement in the cytotoxic activity curve in 22 out of 28 patients (78.6%), irrespective of the target to effector cell ratio. Conclusions The weight loss induced by RYGB modifies the production of cytokines related with NK cell function and improves its activity.

Effect of Weight Loss on Aerobic Capacity in Patients with Severe Obesity Before and After Bariatric Surgery

Severe obesity has been associated with adverse effects on physical capacity. In a prospective study, the aerobic capacity of severely obese patients was measured in order to observe the physiological response to weight loss from bariatric surgery. Sixty-five consecutive patients (40.4 +/- 8.4 years old; 93.8% female; body mass index = 49.4 +/- 5.4 kg/m(2)) were evaluated before bariatric surgery and then 6 and 12 months after surgery. Aerobic capacity was assessed with a scientific treadmill to measure maximal oxygen consumption (VO(2max)), heart rate, blood pressure, time on the treadmill, and distance walked (modified Bruce test). For the three observational periods, VO(2max) was 25.4 +/- 9.3, 29.8 +/- 8.1, and 36.7 +/- 8.3 ml/kg/min; time on the treadmill was 5.4 +/- 1.4, 6.4 +/- 1.6, and 8.8 +/- 1.0 min; and distance walked was 401.8 +/- 139.1, 513.4 +/- 159.9, and 690.5 +/- 76.2 m. For these variables, significant results (p = 0.0000) were observed for the two postoperative periods in relation to the preoperative period. Severely obese individuals increased their aerobic capacity after successful bariatric surgery. The data also suggests that a positive and progressive relationship between weight loss and improvement in fitness as a moderate loss of weight 6 months after surgery already showed some benefit and an additional reduction in weight was associated with a better performance in the aerobic capacity tests at the 12-month follow-up.

Trends in morbid obesity and in bariatric surgeries covered by the Brazilian public health system

Background Obesity is an increasingly serious public health problem on a global level. Morbid obesity, defined as a body mass index greater than 40 kg/m2, is associated with increased mortality and a high burden of obesity-related morbidities. Methods To study the prevalence of morbid obesity in Brazil, three national anthropometric surveys were reanalyzed. Data about bariatric surgeries were obtained from the Ministry of Health Hospital Information System, which is available online. Results A 255% rise in the prevalence of morbid obesity was observed, starting at 0.18% in 1975-1976 and growing to 0.33% in 1989 and 0.64% in 2002-2003. There was a higher rate in the South in the first two surveys, but the prevalence in the Southeast rose steadily, reaching 0.77% in 2002-2003 and overtaking the South. Since 1999, the Brazilian Unified Health System has covered surgical treatment for morbid obesity. From 2000 to 2006, there was a sixfold increase in the number of surgeries, which topped the 2,500 mark in 2006. The geographic distribution of these surgeries is heavily concentrated in the Southeast, the most developed region of Brazil, where there is also the highest prevalence of morbid obesity. This was followed by the Southern region. Conclusions The figures for the rise in morbid obesity in Brazil are startling, especially the increase among men. This is a situation that calls for further study, alongside measures to encourage the adoption of healthy lifestyles. Preventive measures aimed at slowing down or reversing the obesity epidemic are urgently required

Surgical Treatment of Morbid Obesity: Mid-term Outcomes of the Laparoscopic Ileal Interposition Associated to a Sleeve Gastrectomy in 120 Patients

The aim of this study was to evaluate the mid-term outcomes of the laparoscopic ileal interposition associated to a sleeve gastrectomy (LII-SG) for the treatment of morbid obesity. The procedure was performed in 120 patients: 71 women and 49 men with mean age of 41.4 years. Mean body mass index (BMI) was 43.4 +/- 4.2 kg/m(2). Patients had to meet requirements of the 1991 NIH conference criteria for bariatric operations. Associated comorbidities were observed in all patients, including dyslipidemia in 51.7%, hypertension in 35.8%, type 2 diabetes in 15.8%, degenerative joint disease in 55%, gastroesophageal reflux disease in 36.7%, sleep apnea in 10%, and cardiovascular problems in 5.8%. Mean follow-up was 38.4 +/- 10.2 months, range 25.2-61.1. There was no conversion to open surgery nor operative mortality. Early major complications were diagnosed in five patients (4.2%). Postoperatively, 118 patients were evaluated. Late major complications were observed in seven patients (5.9%). Reoperations were performed in six (5.1%). Mean postoperative BMI was 25.7 +/- 3.17 kg/m(2), and 86.4% were no longer obese. Mean %EWL was 84.5 +/- 19.5%. Hypertension was resolved in 88.4% of the patients, dyslipidemia in 82.3%, and T2DM in 84.2%. The LII-SG provided an adequate weight loss and resolution of associated diseases during mid-term outcomes evaluation. There was an acceptable morbidity with no operative mortality. It seems that chronic ileal brake activation determined sustained reduced food intake and increased satiety over time. LII-SG could be regularly used as a surgical alternative for the treatment of morbid obesity.

Spirometric Function Improves in the Morbidly Obese After 1-Year Post-surgery

Obesity can negatively affect pulmonary function tests, with or without clinical symptoms, but the impact of bariatric weight loss is still debated. Aiming to document such profile in a consecutive homogeneous population, a prospective cohort study was undertaken. Sixty-one patients (100% females, age 40 +/- 8 years, BMI 49 +/- 5 kg/m(2) and without respiratory disease) were enrolled. Spirometric analysis was carried out to compare preoperative respiratory pattern with outcome after 6 and 12 months. Variables included vital capacity (VC), expiratory reserve volume (ERV), forced expiratory volume (1 s) (FEV1), FEV1/FVC ratio and maximum voluntary ventilation (MVV). Correlation of results with weight loss was examined. The following initial variables exhibited significant difference when compared to the 12-month postoperative control: FVC (P = 0.0308), FEV1/FVC (P = 0.1998), MVV (P = 0.0004) and ERV (P = 0.2124). Recovery of FVC and FEV1/FVC occurred earlier by 6 months. The most seriously depressed preoperative finding was ERV, which even after 1 year still remained inadequate. (1) Pulmonary limitations were diagnosed in approximately one third of the population. (2) Changes were demonstrated for FVC, FEV1/FVC, ERV and MVV. (3) FEV1 and FEV1/FVC were acceptable due to the absence of an obstructive pattern. (4) Two variables increased by 6 months (FEV1/FVC and ERV), whereas recovery for others was confirmed after 1 year. (5) The only exception was ERV which continued below the acceptable range.

Bariatric Surgery in Adolescents: Preliminary 1-year Results with a Novel Technique (Santoro III)

Background Bariatric surgery (BS) was recognized as the only treatment for morbid obesity in adolescents. Classic surgical procedures are based on mechanical restriction and/or malabsorption, resulting in a large number of possible complications and demanding lifelong medical attention. A novel BS design, the Santoro III procedure, relies on modifying secretion of the satiogenic hormones GLP-1 and PYY. This approach avoids common BS complications such as prostheses, narrow anastomoses, excluded segments, and malabsorption. This study describes the 1-year follow-up of the first ten adolescents operated on using the Santoro III technique in a pediatric surgical service. Methods Ten adolescents, mean age 16.1 +/- 1.7 years with body mass index (BMI) greater than 40 kg/m(2) (range 44 to 72 kg/m(2)), refractory to at least 2 years of medical weight loss treatment were selected by a multidisciplinary team to undergo BS. This operation consists of a sleeve gastrectomy with enteroomentectomy and partial gastro-ileal derivation. Results After 1 year, mean body weight decreased from 140.3 to 88.6 kg, and BMI decreased from 52.8 +/- 9.5 kg/m(2) to 33.4 +/- 7.7 kg/m(2), with percent of excess BMI lost as 83.9 +/- 17.1%. Glucose, insulin, total cholesterol, LDL-cholesterol, and triglyceride levels decreased significantly, while HDL-cholesterol, hemoglobin, and albumin levels remained unchanged. There were no mortalities or reoperations. The two complications that presented during the trial (intraperitoneal abscess and polyneuritis) resolved with medical treatment without sequelae. All the patients returned to their normal activities and their BMI began to stabilize approximately 2 years following surgery. Conclusions The Santoro III procedure is an attractive option for adolescent BS, with promising 1-year follow-up results. These initial studies should be monitored for long-term outcomes and confirmed on a larger group of patients.

The Incapacity of the Surgeon to Identify NASH in Bariatric Surgery Makes Biopsy Mandatory

Nonalcoholic steatohepatitis (NASH) is a morbid condition highly related to obesity. It is unclear if the macroscopic liver appearance correlates with the histopathologic findings. The goal of this prospective study was to determine the relationship between the intraoperative liver appearance and the histopathologic diagnosis of NASH in morbidly obese subjects undergoing bariatric surgery. We also aimed to determine variables that could predict NASH preoperatively. Consecutive 51 subjects undergoing bariatric surgery without evidence of other liver disease underwent intraoperative liver biopsy. An intraoperative liver visual (macroscopic and tactile examination) was recorded. The liver aspect was compared with the liver histologic findings. Histological assessment was categorized into two groups: NASH and non-NASH (including normal histology and simple steatosis). Clinical and biochemical parameters were obtained from the patient databases and were compared between groups to identify preoperatively predictive factors of NASH. From 51 patients, only one presented totally normal histology. Forty-three (86.2%) presented simple steatosis, and seven (13.7%) were classified as NASH. Clinical parameters were not different between groups. At biochemical analysis, only VLDL cholesterol level was significantly higher in the NASH group (p = 0.037) but yet within the normal range. Association between macroscopic liver appearance and the presence of histological NASH is poor (sensitivity of 14%, specificity of 56%, positive predictive value of 5%, and negative predictive value of 80%). No predictor of NASH was found. Surgeons` evaluation could not identify NASH individuals. Routine liver biopsy during bariatric operations is mandatory to differentiate NASH and nonalcoholic fatty liver disease.

Enterohormonal changes after digestive adaptation: Five-year results of a surgical proposal to treat obesity and associated diseases

Background Recent physiological knowledge allows the design of bariatric procedures that aim at neuroendocrine changes instead of at restriction and malabsorption. Digestive adaptation is a surgical technique for obesity based in this rationale. Methods The technique includes a sleeve gastrectomy, an omentectomy and a jejunectomy that leaves initial jejunum and small bowel totaling at least 3 m (still within normal variation of adult human bowel length). Fasting ghrelin and resistin and fasting and postprandial GLP-1 and PYY were measured pre- and postoperatively. Results Patients: 228 patients with initial body mass index (BMI) varying from 35 to 51 kg/m(2); follow-up: I to 5 years; average EBMIL% was 79.7% in the first year; 77.7% in the second year; 71.6% in the third year; 68.9% in the fourth year. Patients present early satiety and major improvement in presurgical comorbidities, especially diabetes. Fasting ghrelin and resistin were significantly reduced (P<0.05); GLP-1 and PYY response to food ingestion was enhanced (P<0.05). Surgical complications (4.4%) were resolved without sequela and without mortality. There was neither diarrhea nor detected malabsorption. Conclusions Based on physiological and supported by evolutionary data, this procedure creates a proportionally reduced gastrointestinal (GI) tract that amplifies postprandial neuroendocrine responses. It leaves basic GI functions unharmed. It reduces production of ghrelin and resistin and takes more nutrients to be absorbed distally enhancing GLP-1 and PYY secretion. Diabetes was improved significantly without duodenal exclusion. The patients do not present symptoms nor need nutritional support or drug medication because of the procedure, which is safe to perform.

Nutritional Course of Patients Submitted to Bariatric Surgery

Background Surgical treatment has proved to be effective for weight loss, improving the quality of life of obese individuals. However, metabolic and nutritional deficiencies may occur during the late postoperative period. The objective of the present study was to assess the metabolic and nutritional profile of grade III obese individuals for 12 months after Roux-en-Y gastric bypass (RYGBP). Methods Forty-eight patients with mean body mass index (BMI) of 51.9 +/- 7.8 kg/m(2) were submitted to RYGBP. Anthropometric, food intake, and biochemical data were obtained before and for 12 months after surgery. Results There was an average weight and body fat reduction of 35% and 46%, respectively. Calorie intake was reduced, ranging from 773 +/- 206 to 1035 +/- 345 kcal during the study. Protein intake remained below recommended values throughout follow-up, corresponding to 0.5 +/- 0.3 g/kg/current body weight/day during the 12th month. Iron and fiber intake was significantly reduced, remaining below recommended levels throughout the study. Serum cholesterol, low-density lipoprotein cholesterol, and glycemia were reduced. Albumin deficiency was present in 15.6% of subjects at the beginning of the study vs 8.9% at the end, calcium deficiency was present in 3.4% vs 16.7%, and iron deficiency was present in 12.2% vs 14.6%. Conclusions RYGBP was effective for weight loss and for the reduction of obesity rates and risk factors for comorbidities. The diet of these patients, who frequently present inadequate intake of macronutrients and micronutrients, should receive special attention. Patient follow-up and assessment at short intervals are necessary for an early correction of nutritional deficiencies.

Early Identification of Infectious Complications in Bariatric Surgery by the Determination of Peritoneal and Systemic Cytokines

Obesity has become a global epidemic and bariatric surgery is one of the therapeutic tools to deal with it. Postoperative complications can occur, such as staple line dehiscence and anastomotic leaks, leading to increased patient mortality. The diagnosis of these complications is frequently difficult. The objective of the present study was to determine whether peritoneal and systemic cytokines could early detect those complications. All patients who underwent open Roux-en-Y gastric bypass from February 2007 to August 2008 were prospectively evaluated. Blood and peritoneal effluent from the drain were collected for the determination of cytokine levels. We also evaluated the clinical signs and the leukograms of the patients. A total of 107 obese patients were studied. Ninety patients had no complications; 17 had at least one infectious complication which include five cases of staple line dehiscence. Until the third postoperative day, the vital signs and the leukogram did not predict the onset of infectious complications, but the cytokines (interleukin-1 beta and interleukin-6) were early markers of these complications. Cytokines are good predictors of poor postoperative evolution in bariatric surgery since peritoneal cytokines diagnose better these infectious complications even before changes in blood count and before the occurrence of clinical manifestations.

Change in Predicted 10-Year Cardiovascular Risk Following Roux-en-Y Gastric Bypass Surgery: Who Benefits?

The risk of developing cardiovascular disease is higher in obese than in non-obese individuals. Surgery for obesity is effective in reducing weight and resolution of diabetes, hypertension, and dyslipidemia. Our aim was to assess the estimated 10-year cardiovascular risk of obese patients before and after treatment of obesity with a gastric bypass. Weight, body mass index systolic and diastolic blood pressure, lipid profile, glycemia, and history of cardiovascular disease were obtained for obese patients before and 2 years after Roux-en-Y gastric bypass surgery. Ten-year cardiovascular risk was calculated using the Framingham score. Forty-two patients were included in the study. We observed a significant reduction (p < 0.05) of 10-year cardiovascular risk mainly associated with weight reduction and improvement of comorbidities associated with obesity. The benefits were greater among patients who already presented known risk factors such as diabetes and hypertension. Superobese patients benefited as early as 2 years after surgery, when weight loss was greater. Weight loss secondary to surgery was sustained after 2 years and promoted improvement of comorbidities, with an important reduction of 10-year cardiovascular risk especially among patients with previous risk factors.

Effects of Inspiratory Muscle Training on Muscular and Pulmonary Function After Bariatric Surgery in Obese Patients

This study seeks to assess the effect of inspiratory muscle training (IMT) on pulmonary function, respiratory muscle strength, and endurance in morbidly obese patients submitted to bariatric surgery. Thirty patients were randomly assigned to sham muscular training, or to IMT with a threshold device (40% of maximum inspiratory pressure, MIP), for 30 min/day, from the 2nd until 30th postoperative (PO) day. All of them were submitted to a standard respiratory kinesiotherapy and early deambulation protocol. Data on spirometry, maximum static respiratory pressures, and respiratory muscle endurance were collected on the PO days 2, 7, 14, and 30 in a blinded matter. IMT enabled increases in PO MIP and endurance, and an earlier recovery of the spirometry parameters FEV(1), PEF, and FEF(25-75%). Comparing to preoperative values, MIP was increased by 13% at the 30th PO day in the trained group, whereas control group had a reduction of 8%, with higher values for the IMT group (30th PO, IMT-130.6 +/- 22.9 cmH(2)O; controls-112.9 +/- 25.1 cmH(2)O; p < 0.05). Muscular endurance at the 30th PO day was increased in the trained group comparing to preoperative value (61.5 +/- 39.6 s vs 114.9 +/- 55.2 s; p < 0.05), a finding not observed in the control group (81.7 +/- 44.3 vs 95.2 +/- 42.0 s). IMT improves inspiratory muscle strength and endurance and accounts for an earlier recovery of pulmonary airflows in morbidly obese patients submitted to bariatric surgery.

Roux-en-Y Bypass Gastroplasty: Markers of Oxidative Stress 6 Months After Surgery

This study examined the effect of weight loss on energy intake, vitamin C, E, beta-carotene (diet/blood), reduced glutathione (GSH), C-reactive protein (CRP), thiobarbituric acid reactive substances (TBARS), catalase, and myeloperoxidase, in patients with Roux-en-Y bypass gastroplasty. Prospective clinical study with control (C) and bariatric (B) groups (n = 20 each). Age was 38.8 +/- 11.1 (C) and 37.8 +/- 11.2 years (B), and body mass indices (BMI) were 22.4 +/- 2.4 and 48.1 +/- 8.7 kg/m(2), respectively. Group C was assessed on a single occasion and B at three time points (basal period and 3 and 6 months after gastroplasty). BMI was decreased at three (38.3 +/- 1.7, P = 0.018) and 6 months after surgery (34.9 +/- 1.7, P < 0.001). Mean weight loss was 20.53 +/- 1.1 after three and 27.96 +/- 1.3 kg after 6 months. Serum vitamin C and beta-carotene (P < 0.01 and P < 0.001, respectively) were increased at 6 months compared to basal. Basal serum vitamin C (P = 0.001) and beta-carotene (P < 0.001) were lower compared to controls. Serum vitamin E corrected for cholesterol and triglycerides was higher in group B at three (P = 0.01) and 6 months (P = 0.001) and lower at basal (P < 0.001) compared to controls. GSH was higher in controls (P < 0.001) compared to basal. Catalase (P = 0.01) and TBARS (P < 0.001) were higher in group B at 6 months. TBARS were higher (P < 0.001) at basal compared to controls. Myeloperoxidase and CRP decreased in group B after three (P = 0.028, P = 0.010) and 6 months (P < 0.001, P = 0.001), respectively. Roux-en-Y bypass gastroplasty led to decreased proinflammatory parameters together with increased nutritional antioxidants, catalase, and TBARS, and decreased GSH 6 months after surgery.

Trends in Morbid Obesity and in Bariatric Surgeries Covered by the Brazilian Public Health System

Obesity is an increasingly serious public health problem on a global level. Morbid obesity, defined as a body mass index greater than 40 kg/m(2), is associated with increased mortality and a high burden of obesity-related morbidities. To study the prevalence of morbid obesity in Brazil, three national anthropometric surveys were reanalyzed. Data about bariatric surgeries were obtained from the Ministry of Health Hospital Information System, which is available online. A 255% rise in the prevalence of morbid obesity was observed, starting at 0.18% in 1975-1976 and growing to 0.33% in 1989 and 0.64% in 2002-2003. There was a higher rate in the South in the first two surveys, but the prevalence in the Southeast rose steadily, reaching 0.77% in 2002-2003 and overtaking the South. Since 1999, the Brazilian Unified Health System has covered surgical treatment for morbid obesity. From 2000 to 2006, there was a sixfold increase in the number of surgeries, which topped the 2,500 mark in 2006. The geographic distribution of these surgeries is heavily concentrated in the Southeast, the most developed region of Brazil, where there is also the highest prevalence of morbid obesity. This was followed by the Southern region. The figures for the rise in morbid obesity in Brazil are startling, especially the increase among men. This is a situation that calls for further study, alongside measures to encourage the adoption of healthy lifestyles. Preventive measures aimed at slowing down or reversing the obesity epidemic are urgently required.

Prospective and Randomized Comparison of Two Techniques of Staple Line Reinforcement During Open Roux-en-Y Gastric Bypass: Oversewing and Bioabsorbable Seamguard (R)

Aims: Surgical staple line dehiscence usually leads to severe complications. Several techniques and materials have been used to reinforce this stapling and thus reduce the related complications. The objective was to compare safety of two types of anastomotic reinforcement in open gastric bypass. Methods: A prospective, randomized study comparing an extraluminal suture, fibrin glue, and a nonpermanent buttressing material, Seamguard (R), for staple line reinforcement. Fibrin glue was excluded from the study and analysis after two leaks, requiring surgical reintervention, antibiotic therapy, and prolonged patient hospitalization. Results: Twenty patients were assigned to the suture and Seamguard reinforcement groups. The groups were similar in terms of preoperative characteristics. No staple line dehiscence occurred in the two groups, whereas two cases of dehiscence occurred in the fibrin glue group. No mortality occurred and surgical time was statistically similar for both techniques. Seamguard made the surgery more expensive. Conclusion: In our service, staple line reinforcement in open bariatric surgery with oversewing or Seamguard was considered to be safe. Seamguard application was considered to be easier than oversewing, but more expensive.