Jonathan Barry

Extended thromboprophylaxis reduces incidence of postoperative venous thromboembolism in laparoscopic bariatric surgery

BACKGROUND Venous thromboembolism (VTE) after laparoscopic bariatric surgery is a significant cause of morbidity and mortality. The objective of the present study was to study the incidence of symptomatic VTE in extended thromboprophylaxis regimens using dalteparin at an independent hospital in England, United Kingdom. METHODS A prospective database of all patients undergoing bariatric surgery was retrospectively analyzed. All patients underwent VTE prophylaxis regimen using perioperative and extended postoperative low-molecular-weight heparin (dalteparin 2500 IU preoperatively, followed by 5000 IU daily postoperatively). The treatment period was 1 week for laparoscopic gastric banding or 3 weeks for all other procedures. Inferior vena cava filters were used in selected patients with thrombophilia, a history of pulmonary embolism, or >1 episode of deep vein thrombosis. The endpoint was the incidence of symptomatic VTE. RESULTS A total of 735 patients underwent laparoscopic bariatric surgery, all of whom received dalteparin. The postoperative VTE incidence was 0%. The 30-day and 90-day all-cause mortality rate was 0%. A total of 3 adverse bleeding events occurred. CONCLUSION An extended VTE prophylaxis regimen using low-molecular-weight heparin is simple and effective and was associated with a low incidence of bleeding complications.

Does bariatric surgery adversely impact on diabetic retinopathy in persons with morbid obesity and type 2 diabetes? A pilot study

AIMS To assess the incidence and progression of diabetic retinopathy (DR) 12 months post bariatric surgery in persons with morbid obesity and type 2 diabetes. METHODS A retrospective pilot analysis of electronic hospital records between 1998 and 2012. RESULTS 40 of 148 subjects had pre- and post-surgery DR screening. Of those without DR pre-surgery 1.5% (n = 26) progressed to minimum background DR (BDR) post surgery. Those with minimum BDR (n = 9) pre-surgery revealed no progression, with 55.6% (n = 5) showing evidence of regression. One person with moderately severe BDR and two with pre-proliferative DR (PPDR) prior to surgery experienced progression. Two persons with PPDR prior to surgery remained under the hospital eye services and were therefore not eligible to be re-assessed by the screening service. CONCLUSIONS There was a low incidence of new DR and progression of DR in those either without evidence of retinopathy or with minimal BDR prior to surgery with some subjects showing evidence of regression. There was however a risk of progression of DR in those with moderate BDR or worse, and should therefore be monitored closely post-surgery.

Temporal changes in glucose homeostasis and incretin hormone response at 1 and 6 months after laparoscopic sleeve gastrectomy

BACKGROUND Bariatric surgery is an effective treatment for morbid obesity. Current literature reports significant improvements in glucose homeostasis after malabsorptive surgery. There is limited evidence on the effects of laparoscopic sleeve gastrectomy (SG) on glucose-insulin homeostasis and postoperative incretin hormone response. The objective of this study was to examine the metabolic effects of SG on temporal changes in insulin and glucose homeostasis, incretin hormones and hepatic insulin clearance in patients with impaired glucose tolerance (IGT) and type 2 diabetes (T2 DM). METHODS A nonrandomized prospective study comprising 22 participants undergoing SG (body mass index [BMI] 50.1 kg/m(2), glycated hemoglobin [HbA1c] 53 mmol/mol) and 15 participants undergoing biliopancreatic diversion (BPD) (BMI 62.1 kg/m(2), HbA1c 58 mmol/mol). Serial measurements of glucose, insulin, C-peptide, glucagon like peptide-1 (GLP-1) and glucose-dependent insulinotropic hormone (GIP) were performed during oral glucose tolerance testing preoperatively and 1 and 6 months postoperatively. Areas under the curve (AUC) were examined at 30, 60, and 120 minutes. RESULTS Within the SG group, significant improvements were observed respectively at 1 and 6 months in glucose control (HbA1c: -0.9%, -1.3%), measures of insulin sensitivity (fasting insulin: -4.8 mU/L, -8.5 mU/L; fasting C-peptide: -0.6 pmol/L, -1.1 pmol/L; Homeostasis Model Assessment [HOMA-IR]: -0.144, -0.174; HOMA %S:+29.6,+92.4), hepatic insulin clearance (+0.07,+0.13) and postprandial GLP-1 response (AUC0-30 pmol h L(-1):+300,+331, AUC0-60:+300,+294, AUC0-120:+316,+295). These results were comparable to the BPD group. CONCLUSIONS SG is associated with significant early improvements in insulin sensitivity and incretin hormone response and results in significant improvements in IGT/T2 DM.

Changes in inflammatory markers after sleeve gastrectomy in patients with impaired glucose homeostasis and type 2 diabetes

BACKGROUND Bariatric surgery is an effective treatment for morbid obesity. Obesity and type 2 diabetes are associated with chronic inflammation. There is lack of data examining the effects of sleeve gastrectomy (SG) on inflammatory biomarkers. Our aim was to study the effects of SG on specific cytokines associated with obesity including interleukin-6 (IL-6), interleukin-10 (IL-10), leptin, adiponectin, and C-reactive protein (CRP) preoperatively, 1 and 6 months after surgery. METHODS A nonrandomized prospective study comprising of 22 participants with impaired glucose homeostasis and type 2 diabetes undergoing SG (body mass index 50.1 kg/m(2), glycated hemoglobin [HbA1c] 53 mmol/mol). Serial measurements of IL-6, IL-10, leptin, adiponectin, and CRP were performed during oral glucose tolerance testing preoperatively, 1 and 6 months postoperatively. RESULTS We observed significant improvements at 1 and 6 months in leptin (P≤.001) and CRP (P = .003) after SG. We also observed a significant reduction in IL-6 at 6 months (P = .001). No statistically significant differences were observed for adiponectin and IL-10. CONCLUSION This study is the first to examine the detailed changes in the inflammatory cytokines after SG. Our study shows significant improvements in the inflammatory biomarkers after SG in patients with impaired glucose homeostasis and type 2 diabetes.

Bariatric surgery as a treatment for idiopathic intracranial hypertension: a systematic review

BACKGROUND Idiopathic intracranial hypertension (IIH) is a chronic neurologic disease that may result in persistent and debilitating symptoms that are refractory to conventional treatments. OBJECTIVES The aim of this study was to systematically review the effect of bariatric weight reduction surgery as a treatment for IIH. METHODS A comprehensive literature search was conducted using the following databases: MEDLINE, EMBASE, PubMed, Scopus, Web of Sciences, and the Cochrane Library. No restrictions were placed on these searches, including the date of publication. RESULTS A total of 85 publications were identified, and after initial appraisal, 17 were included in the final review. Overall improvement in symptoms of IIH after bariatric surgery was observed in 60 of the 65 patients observed (92%). Postoperative lumbar puncture opening pressure was shown to decrease by an average of 18.9 cmH2O in the 12 patients who had this recorded. CONCLUSION Bariatric surgery for weight loss is associated with alleviation of IIH symptoms and a reduction in intracranial pressure. Furthermore, an improvement was observed in patients where conventional treatments, including neurosurgery, were ineffective. Further prospective randomized studies with control groups and a larger number of participants are lacking within the published studies to date. There is, therefore, a strong rationale for the use of bariatric surgery in individuals with IIH for the effective treatment of this condition, as well as the efficacy of weight loss for various other obesity co-morbidities.

Changes in Cognitive Function Following Bariatric Surgery: a Systematic Review

Increased body mass is directly associated with reduced cognitive function. The aim of this study was to systematically review the effect of bariatric weight loss surgery on cognitive function. A comprehensive and unrestricted literature search was conducted using the following databases: MEDLINE, EMBASE, PubMed, Scopus, Web of Sciences, and the Cochrane Library. A total of 414 publications were identified, of which 18 were included in the final review. Cognitive function as measured by a number of different assessment tools was shown to improve following surgically induced weight loss in most studies. Significant and rapid weight loss resulting from bariatric surgery is associated with prompt and sustained improvements in cognitive function including memory, executive function, and cognitive control.

Changes in markers of oxidative stress and DNA damage in human visceral adipose tissue from subjects with obesity and type 2 diabetes

AIMS In the past 30 years, prevalence of obesity has almost trebled resulting in an increased incidence of type 2 diabetes mellitus and other co-morbidities. Visceral adipose tissue is believed to play a vital role, but underlying mechanisms remain unclear. Our aim was to investigate changes in markers of oxidative damage in human visceral adipose tissue to determine levels of oxidative burden that may be attributed to obesity and/or diabetes. METHODS Visceral adipose tissue samples from 61 subjects undergoing abdominal surgery grouped as lean, obese and obese with type 2 diabetes mellitus, were examined using 3 different markers of oxidative stress. Malondialdehyde (MDA) concentration was measured as a marker of lipid peroxidation, telomere length and Comet assay as markers of oxidative DNA damage. RESULTS No significant difference in MDA concentration, telomere length and DNA damage was observed between groups, although longer telomere lengths were seen in the obese with diabetes group compared to the obese group (P<0.05). Lower MDA concentration and longer telomere length were seen in subjects with diabetes compared to those without (P<0.05). DNA damage, analysed via Comet assay, was significantly lower in subjects with diabetes compared to those without (P<0.05). CONCLUSION A paradoxical decrease in oxidative stress and DNA damage was observed in samples from subjects with type 2 diabetes mellitus. Further work is required to investigate this further, however this phenomenon may be due to an up regulation of antioxidant defences in adipose tissue.

Changes in Plasma Levels of N-Arachidonoyl Ethanolamine and N-Palmitoylethanolamine following Bariatric Surgery in Morbidly Obese Females with Impaired Glucose Homeostasis

Aim. We examined endocannabinoids (ECs) in relation to bariatric surgery and the association between plasma ECs and markers of insulin resistance. Methods. A study of 20 participants undergoing bariatric surgery. Fasting and 2-hour plasma glucose, lipids, insulin, and C-peptide were recorded preoperatively and 6 months postoperatively with plasma ECs (AEA, 2-AG) and endocannabinoid-related lipids (PEA, OEA). Results. Gender-specific analysis showed differences in AEA, OEA, and PEA preoperatively with reductions in AEA and PEA in females postoperatively. Preoperatively, AEA was correlated with 2-hour glucose (r = 0.55, P = 0.01), HOMA-IR (r = 0.61, P = 0.009), and HOMA %S (r = −0.71, P = 0.002). OEA was correlated with weight (r = 0.49, P = 0.03), waist circumference (r = 0.52, P = 0.02), fasting insulin (r = 0.49, P = 0.04), and HOMA-IR (r = 0.48, P = 0.05). PEA was correlated with fasting insulin (r = 0.49, P = 0.04). 2-AG had a negative correlation with fasting glucose (r = −0.59, P = 0.04). Conclusion. Gender differences exist in circulating ECs in obese subjects. Females show changes in AEA and PEA after bariatric surgery. Specific correlations exist between different ECs and markers of obesity and insulin and glucose homeostasis.

Association between the preoperative fasting and postprandial C-peptide AUC with resolution of type 2 diabetes 6 months following bariatric surgery

BACKGROUND AND AIMS Bariatric surgery results in the remission of type 2 diabetes mellitus (T2DM) in morbidly obese subjects. The aim of the study was to investigate the predictive value of both static and dynamic measures of C-peptide in relation to T2DM resolution 6 months after bariatric surgery regardless of the operation type. METHODS AND RESULTS A non-randomized prospective study of 24 participants with T2DM undergoing bariatric surgery. Measurements of fasting and 2-hour plasma glucose, insulin, C-peptide and measures of insulin sensitivity were recorded temporally during an oral glucose tolerance test pre-operatively and 6 months post-operatively. A responder was defined with a fasting glucose <5.6 mmol/L and HbA1c <6.0% postoperatively. Within the sample there were 11 responders and 13 non-responders at 6 months. There was a significant difference in the duration of diabetes between the groups. Fasting C-peptide (P≤0.05) and 2-hour C-peptide (P≤0.05) were higher in responders compared to non-responders. Significantly higher C-peptide levels were observed preoperatively at all time points for responders, with significantly higher area under the curve (AUC0-60 and AUC0-120). Using the lower quartiles for C-peptide levels, both fasting C-peptide (>2.5 ng/mL [0.83 nmol/L]) and 2-hour C-peptide (>5.2 ng/mL [1.73 nmol/L]) had a sensitivity and negative predictive value of 100% to predict T2DM remission. Logistic regression showed that C-peptide, duration of diabetes and BMI were associated with response. The area under the ROC curve was 0.94 and a regression model predicted diabetes remission with a sensitivity of 85.7% and a specificity of 88.9%. CONCLUSIONS This study demonstrated that static (fasting) and dynamic (AUC, 2-hour) C-peptide measurements predict T2DM resolution 6 months following bariatric surgery. This work provides insight into C-peptide dynamics as a predictor of response to bariatric surgery.

Predicting the Resolution of Type 2 Diabetes after Bariatric Surgical Procedures: A Concise Review

Bariatric surgery has become an established evidence-based treatment option for diabetes associated with obesity . Numerous studies have demonstrated that bariatric surgery is superior to conventional medical treatment and is effective in achieving resolution of hyperglycaemia or improvement in glycaemic control in type 2 diabetes. However, diabetes remission after bariatric surgery does not occur universally in patients and surgical procedures are associated with the risks of complications. It is imperative to identify patients who are likely to gain the best possible metabolic benefit i.e. resolution of diabetes from bariatric surgery . Several clinical and biochemical factors have been studied to predict diabetes remission following bariatric surgery. This article provides a concise review within this area and describes the available scoring systems to predict diabetes remission.