Effect of Weight Loss following Bariatric Surgery on Myocardial Dispersion of Repolarization in Morbidly Obese Patients

Background Weight-stable obese subjects have an increased risk of arrhythmias and sudden death, even in the absence of cardiac dysfunction, and the risk of sudden cardiac death (SCD) with increasing weight is seen in both genders. The mechanism of unexplained deaths in obese patients is still unclear and may be related to ventricular repolarization abnormalities. The aim of this study is to determine the effect of severe obesity on spatial and transmural ventricular repolarization and to clarify the influence of bariatric surgery with a consequent substantial weight loss on arrhythmogenic substrate in the morbidly obese population. Methods For the study, we enrolled 100 severely obese patients; 50 age-matched non-obese healthy subjects were also recruited as controls. All subjects underwent conventional 12-lead electrocardiography for analysis of spatial and transmural ventricular repolarization assessed by corrected QT dispersion (QTcd), corrected JT dispersion (JTc-d) and transmural dispersion of repolarization, (TDR). All subjects underwent bariatric surgery and were resubmitted to electrocardiographic, biochemical and anthropometric examination 12 months postoperatively. Results Severely obese patients had greater values in QTc-d, JTc-d and TDR than the normal-weight controls. Bariatric surgery reduced significantly the QTcd value, JTc-d value and TDR value. There was a significant correlation between decrease of heterogeneity of repolarization indexes (QTd, JTd and TDR) and bariatric surgery-induced weight loss. Conclusions In severely obese patients, surgicallyinduced weight loss is associated with significant decrease in the heterogeneity of ventricular repolarization. The reduction of spatial (QTc-d, JTc-d) and transmural dispersion of repolarization (TDR) may be of clinical significance, by reducing the risk of potentially fatal arrhythmias in morbidly obese subjects.     

Clinical Significance of Central Obesity in Laparoscopic Bariatric Surgery

Background: Laparoscopic surgery had increased the interest and growth of bariatric surgery. Whether central obesity has any adverse effect in laparoscopic bariatric surgery is not clear. Methods: 612 morbidly obese patients received laparoscopic bariatric surgery,in a prospectively controlled clinical trial of the outcome of the bariatric surgery. For comparison, subjects were dichotomized into either a central obesity group or peripheral obesity group, based on waist/hip ratio (WHR). Various biochemistry and blood count variables, and perioperative and postoperative results were measured. Results: There were more female (458) than male patients (154). Male patients had higher BMI, and female patients were younger. 56 of 154 male patients (36.4%) belonged to the central obesity (WHR >1.0), and 321 of 458 female patients (70.1%) had central obesity (WHR >0.85). Central obesity was associated with age but not with BMI in males. In females, central obesity was associated with increased BMI. Central obesity predicted increased hyperglycemia and triglyceride levels in both male and female patients. Male patients with central obesity had higher WBC counts than the other patients. Although central obesity was associated with more intra-operative blood loss and prolonged recovery in female patients, there was no increase in complication rate or difference in postoperative weight loss. Conclusion: Central obesity is associated with a higher degree of hyperglycemia, hyperlipidemia and leukocytosis in morbidly obese patients who undergo bariatric surgery. Although there is increased technical difficulty in patients with severe central obesity, laparoscopic bariatric surgery is safe and effective in producing weight loss.     

Pancreas transplantation after bariatric surgery

Obese transplant candidates are at increased risk for perioperative and postoperative complications. In many transplant programs, morbid obesity is considered to be an exclusion criterion for transplantation. The only potential option that would grant these patients access to transplant is weight loss. Non-operative weight loss strategies such as behavioral modifications, exercise, diet, or medication have only very limited success in achieving long-term weight loss. In contrast, bariatric surgery was shown to achieve not only more excessive weight loss, but more importantly, this weight loss can be sustained for longer periods of time. Therefore, bariatric surgery presents an attractive option for weight loss for morbidly obese transplant candidates. We report our experience with four patients who underwent bariatric surgery prior to successful pancreas transplantation. Even though gastric bypass and laparoscopic adjustable gastric band present as equivalent alternatives for weight reduction, we believe that in the population of morbidly obese diabetic patients who are possible candidates for pancreas transplantation, laparoscopic adjustable gastric band placement is the more suitable procedure.     

Impact of bariatric surgery on cardiovascular and musculoskeletal morbidity

BACKGROUND: Obesity is currently recognized as a global epidemic. According to recent statistics, the prevalence of obesity increased from 13.8% of the Canadian population in 1978-1979 to 23.1% in 2004, and the prevalence of morbid obesity increased from .9% in 1978-1979 to 2.7% in 2004. Obesity is a known risk factor for highly prevalent chronic diseases, including cardiovascular and musculoskeletal disorders. The objective of the study was to assess the impact of bariatric surgery on cardiovascular and musculoskeletal morbidity. METHODS: This was an observational study that compared a cohort of 1035 morbidly obese patients treated with bariatric surgery at the Centre for Bariatric Surgery, McGill University Health Centre with a matched cohort of 5746 morbidly obese nonsurgically treated controls. Data were obtained from the Quebec provincial health insurance database (Régie de l'Assurance Maladie du Québec). Morbidity indicators included diagnoses or treatment for cardiovascular or musculoskeletal disorders. RESULTS: Patients who underwent bariatric surgery had a significant 62% mean reduction in excess weight and 32% mean reduction in body mass index (P < .001). Compared with the matched controls, patients who had undergone bariatric surgery had significantly lower rates of diagnoses and treatments related to cardiovascular and musculoskeletal conditions. CONCLUSIONS: These results indicate that bariatric surgery is effective in reducing weight and significantly reduces the risk of cardiovascular and musculoskeletal morbidity.     

Outcome Following Bariatric Surgery in Super versus Morbidly Obese Patients: Does Weight Matter?

Background: Numerous investigators have attempted to identify prognostic indicators for successful outcome following bariatric surgery. The purpose of this study was to determine whether degree of obesity affects outcome in super obese [>225% ideal body weight (IBW)] versus morbidly obese patients (160-225% IBW) undergoing gastric restrictive/bypass procedures. Methods: Since 1984, 157 patients underwent either gastric bypass or vertical banded gastroplasty. Super obese (78) and morbidly obese (79) patients were followed prospectively, documenting outcome and complications. Results: Super obese patients reached maximum weight loss 3 years following bariatric surgery, exhibiting a decrease in body mass index (BMI) from 61 to 39 kg/m² and an average loss of 42% excess body weight (EBW). Morbidly obese patients had a decrease in BMI from 44 to 31 kg/m² and carried 39% EBW at 1 year. After their respective nadirs, each group began to regain the lost weight with the super obese exhibiting a current BMI of 45 kg/m² (61% EBW) versus 34 kg/m² (52% EBW) in the morbidly obese at 72 months cumulative follow-up. Currently, loss of 50% or more of EBW occurred in 53% of super obese patients versus 72% of morbidly obese (P < 0.01). Twenty-six percent of super obese patients returned to within 50% of ideal body weight (IBW) while 71% of morbidly obese were able to reach this goal (P < 0.01). Co-morbidities and complications related to surgery were similar in each group. Conclusions: Super obese patients have a greater absolute weight loss after bariatric surgery than do morbidly obese patients. Using commonly utilized measures of success based on weight, morbidly obese patients tend to have better outcomes following bariatric surgery.     

The perioperative management of morbidly obese patients (a surgeon's perspective)

One hundred and thirteen morbidly obese patients underwent bariatric surgery. Mean preoperative percentage above ideal weight was 98.3% (SD 30.0%). Mean percentage above ideal weight eighteen months after operation was 19.5% (SD 23.8%). Fifteen patients (13.3%) required pre-operative weight loss because of respiratory dysfunction and raised PaCO2. One patient developed asthma in the postoperative period. There were no other clinical postoperative respiratory complications. 40% of patients however did show radiological evidence of basal pulmonary atelectasis on the initial postoperative chest X-ray. All patients had pre-operative cardiological screening: there were no cardiac complications except one case of atrial fibrillation. One patient suffered a proven pulmonary embolus and recovered. Six patients (5.3%) required correction of a pre-operative potassium deficit. No episode of gastric acid aspiration syndrome occurred. 58% of patients presenting for obesity surgery had identifiable psychopathology. Despite strict pre-operative psychiatric screening, 15% of patients coming to operation required postoperative psychiatric management.     

Surgical Treatment of Morbid Obesity in Schizophrenic Patients

Background: Newer antipsychotic medications have greatly improved the treatment of schizophrenia, but they are known to be associated with serious weight gain. Little is known about treatment of morbid obesity in this population. Methods: 5 patients with schizophrenia and morbid obesity were studied.Weight loss was compared with that achieved by 165 non-psychotic patients who also underwent bariatric surgery during a 1-year period. Results: 5 morbidly obese patients with schizophrenia underwent bariatric surgery between February 1999 and April 2003. All patients were well controlled on antipsychotics. The median BMI was 54 (51-70) and all had obesity-related co-morbities. All patients had been previously treated unsuccessfully with conservative methods of weight reduction. 3 patients had a duodenal switch operation, 1 patient had a sleeve gastrectomy, and 1 had conversion of a silastic ring gastroplasty to biliopancreatic diversion. All patients were maintained on their antipsychotic medications until 24 hours before surgery. Median percent excess weight loss at 6 months was comparable to that achieved in the control group. Conclusions: Good control of schizophrenia may be achieved by newer therapies but at the risk of weight gain. The results of bariatric surgery in such patients are comparable to those of non-psychotic morbidly obese patients. Further follow-up is needed, but the results are encouraging.     

Preoperative Evaluation for Bariatric Surgery using Transesophageal Dobutamine Stress Echocardiography

Background: Bariatric surgery is an effective option for weight control in morbid obesity. The goal of this study was to assess cardiac risk prior to bariatric surgery using transesophageal-dobutamine stress echocardiography (TE-DSE). Methods: 7 morbidly obese patients (mean BMI 67.7 ± 15.6) were prospectively evaluated by TE-DSE prior to bariatric surgery. Results: All patients underwent TE-DSE without complications. 6 of 7 patients had no evidence of ischemia on TE-DSE. One patient had abnormal TE-DSE showing inferior ischemia and was treated with beta-blockers and nitrates prior to surgery and had no complications. All patients underwent surgery without cardiac complications. 1 patient died at 18 days of sepsis. Over a mean follow-up period of 11 months, the 6 surviving patients have not experienced any cardiac events. Their average weight loss is 58.2 kg. Conclusion: TE-DSE is a valuable noninvasive technique for predicting cardiac risk in morbidly obese patients undergoing bariatric surgery.     

Surgery decreases long-term mortality, morbidity, and health care use in morbidly obese patients

OBJECTIVE: This study tested the hypothesis that weight-reduction (bariatric) surgery reduces long-term mortality in morbidly obese patients. BACKGROUND: Obesity is a significant cause of morbidity and mortality. The impact of surgically induced, long-term weight loss on this mortality is unknown. METHODS: We used an observational 2-cohort study. The treatment cohort (n = 1035) included patients having undergone bariatric surgery at the McGill University Health Centre between 1986 and 2002. The control group (n = 5746) included age- and gender-matched severely obese patients who had not undergone weight-reduction surgery identified from the Quebec provincial health insurance database. Subjects with medical conditions (other then morbid obesity) at cohort-inception into the study were excluded. The cohorts were followed for a maximum of 5 years from inception. RESULTS: The cohorts were well matched for age, gender, and duration of follow-up. Bariatric surgery resulted in significant reduction in mean percent excess weight loss (67.1%, P < 0.001). Bariatric surgery patients had significant risk reductions for developing cardiovascular, cancer, endocrine, infectious, psychiatric, and mental disorders compared with controls, with the exception of hematologic (no difference) and digestive diseases (increased rates in the bariatric cohort). The mortality rate in the bariatric surgery cohort was 0.68% compared with 6.17% in controls (relative risk 0.11, 95% confidence interval 0.04-0.27), which translates to a reduction in the relative risk of death by 89%. CONCLUSIONS: This study shows that weight-loss surgery significantly decreases overall mortality as well as the development of new health-related conditions in morbidly obese patients.     

Gallstone Formation after Weight Loss following Gastric Banding in Morbidly Obese Dutch Patients

Background: Obesity is a risk factor for the development of gallstones. Rapid weight loss may be an even stronger risk factor. We retrospectively assessed the prevalence and risk factors of gallstone formation after adjustable gastric banding (AGB) in a Dutch population. Methods: All patients who underwent AGB between Jan 1992 and Dec 2000 for morbid obesity were invited to take part in this study. Transabdominal ultrasonography of the gallbladder was performed in those patients without a prior history of cholecystectomy (Group A). Additionally, 45 morbidly obese patients underwent ultrasonography of the gallbladder before weight reduction surgery (Group B). Results: 120 patients were enrolled in the study (Group A). Prior history of cholecystectomy was present in 21 patients: 16 before and 5 after AGB. Ultrasonography was performed in 98 patients: gallstones were present in 26 (26.5%). On multivariate analysis, neither preoperative weight, nor maximum weight loss, nor the interval between operation and the postoperative ultrasonography were determinants of the risk for developing gallstone disease. Prevalence of gallstones was significantly lower in the morbidly obese patients who had not yet undergone weight reduction surgery (Group B). Conclusions: Rapid weight loss induced by AGB, is an important risk factor for the development of gallstones. No additional determinants were found. Every morbidly obese patient undergoing bariatric surgery must be considered at risk for developing gallstone disease.     

Low-Back Pain in Morbidly Obese Patients and the Effect of Weight Loss Following Surgery

Background: Although low-back pain (LBP) is a common health problem and a source of significant discomfort, disability and work absences, its incidence, severity and outcome have not been extensively investigated in morbidly obese patients undergoing bariatric surgery. Methods: 50 morbidly obese candidates for vertical banded gastroplasty (VBG) were asked to fill in a questionnaire, to assess the incidence and severity of any existing LBP symptoms. 50 non-obese patients, admitted to our surgical unit for management of several benign conditions, were also asked to fill in the same questionnaire and served as controls. 24 months after VBG, the morbidly obese patients were again evaluated for their LBP symptoms. Results: LBP was identified in 29 morbidly obese patients (58%) preoperatively and in only 12 (24%) of the lean controls (P<0.01). 2 years after VBG, with a significant excess weight loss (P<0.0001), only 10 patients continued to have LBP but less frequently and requiring reduced doses of medications compared with the preoperative condition. In the remaining 19 patients with preoperative positive LBP history, the postoperative weight loss was associated with complete resolution of the symptoms. Conclusion: The frequency of LBP is significantly higher in morbidly obese patients than in lean subjects. Surgical weight reduction results in significant improvement and even disappearance of this obesity co-morbidity.     

Bariatric surgery reduces incidence of atrial fibrillation: a propensity score–matched analysis

Background

Obesity is associated with an increased risk of atrial fibrillation (AF). Bariatric surgery results insubstantial long-term weight loss and the amelioration of several chronic comorbidities. We hypothesized that weightreduction with bariatric surgery would reduce the long-term incidence of AF.

Initial Experience with the Surgical Management of Morbid Obesity Associated with Symptomatic Gastro-esophageal Reflux: A Comparison between Gastroplasty Alone and Gastroplasty with Anterior Fundoplication

The optimal management of patients with morbid obesity and gastro-esophageal reflux disease (GERD) remains an unresolved issue. We have performed a vertical banded gastroplasty combined with an anterior fundoplication (VBG + AF) in 28 selected morbidly obese patients with moderate or severe heartburn. The patients who underwent VBG + AF are compared to patients who had similar heartburn symptoms and underwent gastroplasty alone during this period. In the VBG + AF group there were two treatment failures (7%). In the gastroplasty group there were 63 patients with 15 treatment failures (24%). These differences were independent of demographic and weight loss variables. These results suggest that VBG + AF may provide a superior option for the management of morbidly obese patients with GERD.     

Effect of Bariatric Surgery on Liver Fibrosis

Background

Although bariatric surgery has been shown to improve hepatic steatosis in morbidly obese patients, the effect of weight loss on hepatic fibrosis has not been determined. Since the prognosis of patients with nonalcoholic fatty liver disease is closely related to the development of hepatic fibrosis, it is important to determine the hepatic histology of these patients after weight loss. We therefore evaluated the prevalence of hepatic fibrosis in morbidly obese patients undergoing bariatric surgery and assessed the correlation of histologic changes with weight loss.

Methods

We retrospectively evaluated 78 morbidly obese patients who underwent gastric bypass. Liver biopsies were taken during surgery and after weight loss, and the correlations between histologic findings and hepatic fibrosis were determined.

Results

Of the 78 patients, 35 (44.8%) had fibrosis at first biopsy, and 24 (30.8%) had hepatic fibrosis after weight loss, including 19 of the 35 patients (54.3%) with fibrosis at first biopsy and 5 of the 43 (11.6%) without hepatic fibrosis at first biopsy (P?=?0.027).

Conclusions

Weight loss in morbidly obese patients was associated with a reduction in the prevalence of hepatic fibrosis.     

Hypogonadism as a New Comorbidity in Male Patient's Selection for Bariatric Surgery: Towards an Extended Concept of Metabolic Surgery?

Hypogonadism and subfertility can be frequently associated to obesity. These endocrine alterations may have consequences in the health and quality of life of obese men since they may result in impaired fertility and poor sexual life. As many clinical reports suggest, weight loss can ameliorate hypogonadism and, more generally, alterations in sex hormones. This effect is evident even when weight loss is induced by bariatric surgery. The evidence that hypogonadism in morbidly obese patients can regress after bariatric surgery should lead us to consider it as a modifiable comorbidity associated to obesity. This would have as a consequence that obese male patients with symptomatic hypogonadism could be candidates for bariatric surgery even with a BMI?<?40 kg/m². Controlled clinical trials, involving obese hypogonadal males, should be encouraged.     

The Intragastric Balloon – Smoothing the Path to Bariatric Surgery

Background: Intragastric balloon placement in association with diet for weight reduction is steadily gaining popularity. However, long-term follow-up studies on the effect of this method in maintaining weight loss are lacking. This study evaluated the long-term outcome following balloon removal in morbidly obese patients who had selected this method for weight loss. Methods: 140 morbidly obese patients who refused bariatric surgery because of fear of complications and mortality, underwent intragastric balloon placement and were followed over a 6- to 30-month period (mean 18.3 months) after balloon extraction. The 34 males and 106 females, with median age 38 years (range 16-62), median weight 122 kg (range 85-203), median BMI 42.3 kg/m² (range 35-61.3) and median excess weight (EW) 59 kg (range 29-132), received a Bioenterics Intragastric Balloon (BIB). Excess weight loss (EWL) ≥25% when the BIB was removed was considered a success. Weight fluctuations and any further interventional therapy requested by the patients after balloon removal were recorded. Results: 100 patients (71.4%) lost ≥25% of their EW on balloon extraction and were categorized as successes, while 40 patients (28.6%) did not achieve that weight loss and were categorized as failures of the method. During the follow-up period, 44 of the originally successful patients (31.4%) regained weight and were categorized as recurrences, while the remaining 56 patients (40%) maintained their EWL of ≥25% and were considered long-term successes. During follow-up, 45 patients (32.1%) requested and underwent bariatric surgery for their morbid obesity (21 Adjustable Gastric Band, 11 Laparoscopic Sleeve Gastrectomy, 13 Laparoscopic Gastric Bypass). Of these, 13 (32.5%) were from the group of 40 patients categorized as failures on BIB removal, 28 (63.6%) were from the group of 44 patients whose obesity recurred, and 4 (7.1%) were from the 56 patents who although they maintained successful weight loss requested further weight reduction. Conclusions: The BIB served as a first step and a smooth introduction to bariatric surgery for morbidly obese patients who initially refused surgical intervention. The incidence of surgical intervention was double in patients who initially experienced the benefits of weight loss and then had obesity recurrence, compared with patients in whom the method failed. Indeed, a significant number of patients were assisted in their efforts to lose and maintain an acceptable weight loss over a 6- to 30-month follow-up period.     

Development of Acute Gouty Attack in the Morbidly Obese Population after Bariatric Surgery

Background: Gout is associated with increased body weight. We evaluated the prevalence of gout and acute gouty attacks in the morbidly obese population who underwent bariatric surgery. Methods: The medical records and operative reports of 1,240 patients who underwent bariatric surgery were reviewed retrospectively for weight parameters, BMI, weight loss, medical history of gout, and onset of acute gouty attacks. Results: Of the 1,240 patients, 5 (0.4%) had been previously diagnosed with gout. 2 of these 5 had acute attacks during the postoperative period, and responded succesfully to intravenous colchicine. Conclusion: Although rare, gout must be considered a co-morbid illness in obese and morbidly obese patients. Surgeons should be familiar with the signs and symptoms of attacks in the postoperative period, and be knowledgeable in the management.     

Ala55Val Polymorphism on UCP2 Gene Predicts Greater Weight Loss in Morbidly Obese Patients Undergoing Gastric Banding

BACKGROUND: Variability in weight loss has been observed from morbidly obese patients receiving bariatric operations. Genetic effects may play a crucial role in this variability. METHODS: 304 morbidly obese patients (BMI > or =39) were recruited, 77 receiving laparoscopic adjustable gastric banding (LAGB) and 227 laparoscopic mini-gastric bypass (LMGB), and 304 matched non-obese controls (BMI < or =24). Initially, all subjects were genotyped for 4 SNPs (single nucleotide polymorphisms) on UCP2 gene in a case-control study. The SNPs significantly associated with morbid obesity (P < 0.05) were considered as candidate markers affecting weight change. Subsequently, effects on predicting weight loss of those candidate markers were explored in LAGB and LMGB, respectively. The peri-operative parameters were also compared between LAGB and LMGB. RESULTS: The rs660339 (Ala55Val), on exon 4, was associated with morbid obesity (P = 0.049). Morbidly obese patients with either TT or CT genotypes on rs660339 experienced greater weight loss compared to patients with CC after LAGB at 12 months (BMI loss 12.2 units vs 8.1 units) and 24 months (BMI loss 13.1 units vs 9.3 units). However, this phenomenon was not observed in patients after LMGB. Although greater weight loss was observed in patients receiving LMGB, this procedure had a higher operative complication rate than LAGB (7.5% vs. 2.8%; P < 0.05). CONCLUSION: Ala55Val may play a crucial role in obesity development and weight loss after LAGB. It may be considered as clinicians incorporate genetic susceptibility testing into weight loss prediction prior to bariatric operations.     

Bariatric surgery reduces cancer risk in morbidly obese patients

BackgroundTo assess the effect of bariatric surgery on the cancer risk of patients with morbid obesity because evidence is mounting of an association between obesity and cancer.MethodsWe performed an observational 2-cohort study. The treatment cohort (n = 1035) included patients who had undergone bariatric surgery from 1986 to 2002. The control group (n = 5746) included age- and gender-matched morbidly obese patients who had not undergone weight-reduction surgery and who were identified from a single-payor administrative database. The subjects with physician or hospital visits for a cancer-related diagnosis or treatment within the 6 months previous to the beginning of the study were excluded. The cohorts were followed up for a maximum of 5 years from study inception.ResultsBariatric surgery resulted in a significant reduction in the mean percentage of excess weight loss (67.1%, P <.001). The surgery patients had significantly fewer physician/hospital visits for all cancer diagnoses (n = 21, 2.0%) compared with the controls (n = 487, 8.45%; relative risk .22, 95% confidence interval .143–.347; P = .001). The physician/hospital visits for common cancers such as breast cancer were significantly reduced in the surgery group (P = .001). For all other cancers, the physician/hospital visits showed a trend toward being lower in the surgery group. Because of the low frequencies, statistical significance could not be demonstrated for individual cancer diagnoses.ConclusionThe data suggest that bariatric surgery improves the cancer outcomes in some morbidly obese patients.     

The comparative effects of bariatric surgery on weight and type 2 diabetes

Background: Epidemiological evidence confirms that risk of developing type 2 diabetes is related to weight gain. Weight reduction is beneficial as relative risk is reduced to 0.13 for weight loss >20 kg. This raises the question of effectiveness of bariatric surgery on 1) weight loss and 2) diabetes-related outcomes in morbidly obese patients. Methods: We reviewed the literature using Medline. Only 2 meta-analyses reporting on both outcomes were included, as well as 50 systematic reviews or primary studies. Results: Meta-analyses mainly based on case series data as well as controlled studies confirm that bariatric surgery is highly effective in obtaining weight reduction in morbidly obese patients up to 60% of the excess weight, along with resolution of preoperative diabetes in more than 75% of cases. Among bariatric surgery techniques, malabsorptive procedures (biliopancreatic diversion and gastric bypass) appear to be more effective on both outcomes than restrictive procedures (gastroplasty and gastric banding). Conclusion: Even if more studies are needed to confirm current evidence, bariatric surgery is effective for controlling diabetes. It appears as an efficient strategy from economic modeling due to savings from reduction in diabetes-related costs.