Changes in Cognitive Function Following Bariatric Surgery: An Updated Systematic Review.

Since a previous systematic review published in 2016, there have been further studies investigating the association of changes in cognitive function following bariatric surgery. All studies since the original review that reported at least one element of cognitive function before and after bariatric surgery were eligible. A total of 137 additional studies were identified; 13 were included in addition to the 18 studies previously. Almost all studies reported improvements in at least one domain. Most revealed improvements were limited to a few domains and were not universal. Further findings investigated cognitive function improvement in relation to procedure choice, and mental health or quality of life post-surgery. Further high-powered studies are still necessary, but these findings support the impact of bariatric surgery on cognitive function in obesity.

Benefits in routinely measured liver function tests following bariatric surgery: a retrospective cohort study.

Background: Bariatric surgery is well-established to support long-term metabolic health benefits associated with considerable weight loss. Here, we aim to determine the longer-term impact of bariatric surgery on liver enzymes and associations with other metabolic improvements. Methods: One hundred patients who underwent bariatric surgery between 2007 and 2014 were included, and changes in liver enzymes, anthropometric measures and other parameters were observed over a mean 9.8 years. Results: At the time of surgery, the mean age was 45.4 ± 9.6 years, weight 141.2 ± 31.6 kg, and body mass index (BMI) 50.2 ± 10.1 kg/m2. Most patients underwent sleeve gastrectomy [n = 71] with a mean follow-up duration 9.8 ± 2.3 years. From baseline, alanine transaminase (ALT) reduced by 41.3% within 12 months post-operatively (36.6 ± 29.2 U/L to 21.5 ± 14.9 U/L, p < 0.001), which was sustained at recent follow-up (20.2 ± 10.7 U/L, p < 0.001). There were associated reductions in body weight, BMI, HbA1c, blood pressure and triglycerides. Patients with greater baseline ALT had the greatest reduction in ALT over follow-up. Conclusions: Bariatric surgery is associated with rapid and sustained improvements in routine liver enzymes at 10 years, and sustained improvements in features of the metabolic syndrome. Supplementary Information: The online version contains supplementary material available at 10.1007/s40200-023-01311-4.

Temporal Effects of Bariatric Surgery on Adipokines, Inflammation and Oxidative Stress in Subjects with Impaired Glucose Homeostasis at 4 Years of Follow-up.

BACKGROUND: Previous studies have examined changes in plasma markers of inflammation and oxidative stress up to 24 months following bariatric surgery, but there is limited evidence on the long-term effects of bariatric surgery. OBJECTIVES: To examine the effects of bariatric surgery on adipokines (adiponectin, leptin), inflammatory cytokines [C-reactive protein (CRP), interleukin-6 (IL-6), interleukin-10(IL-10)] and global plasma measures of oxidative stress [thiobarbituric acid reactive substances (TBARS) and total antioxidant status (TAOS) 1 and 6 months, and 4 years post-surgery in subjects with obesity and impaired glucose regulation. METHODS: A prospective study comprising of 19 participants (13 females, mean age 50.4 ± 6.2 years, mean body mass index (BMI) 54 ± 14 kg/m2, 17 type 2 diabetes) undergoing bariatric surgery (10 sleeve gastrectomy, 6 biliopancreatic diversion, 2 Roux-en-Y gastric bypass and 1 laparoscopic adjustable gastric banding). Serial measurements of the above markers were made pre-operatively, 1 and 6 months and 4 years post-operatively. RESULTS: Compared to pre-operative levels, significant decreases were seen 4 years post-operatively in CRP (11.4 vs 2.8 ng/mL, p < 0.001), IL-6 (8.0 vs 2.1 pg/mL, p < 0.001) and leptin (60.7 vs 32.1 pg/mL, p = 0.001). At 4 years, both fasting and 120 min TAOS significantly increased by 35% and 19% respectively. However, fasting and 120 min TBARS did not show any significant changes. CONCLUSION: To our knowledge, no other studies have described changes in inflammation and oxidative stress at 4 years following bariatric surgery. This study contributes to the current literature supporting the longer-term beneficial effect of bariatric surgery on chronic inflammation and oxidative stress.

Effect of Laparoscopic Sleeve Gastrectomy on Static and Dynamic Measures of Glucose Homeostasis and Incretin Hormone Response 4-Years Post-Operatively.

INTRODUCTION: There is limited literature available on the long-term effect of bariatric surgery especially laparoscopic sleeve gastrectomy (LSG) on the incretin hormone response. AIM: Our primary aim was to investigate changes in glucose metabolism and incretin hormone responses in participants with impaired glucose regulation approximately 4 years after LSG. The secondary aim was to examine the long-term incretin hormone changes of biliopancreatic diversion (BPD). METHOD: A non-randomised prospective study comprising of 10 participants undergoing LSG and 6 participants undergoing BPD. Serial measurements of glucose, insulin, C-peptide, glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) were performed during an oral glucose tolerance test pre-operatively and 1 month, 6 months and at approximately 4-7 years post-operatively. Area under the curve (AUC) was examined at 60 and 120 min. RESULTS: In the LSG group, a significant reduction in 2-h plasma glucose (2 h PG), HbA1c and HOMA-IR was observed at 4 years. Compared with pre-operative levels, significant increases in post-glucose GLP-1 secretion were observed at 1 and 6 months, but not maintained at 4 years. A linear increase was seen in post-glucose GIP response at 1 month and 6 months and 4 years. Within the BPD group, a reduction in HbA1c along with an increase GLP-1 response was observed at 7 years. CONCLUSION: An increase in GLP-1 response was not preserved at 4 years, but a significant increase in GIP response was observed along with improved glycaemic control following LSG.

The influence of attachment orientation on weight loss, eating behaviour and other health outcomes among patients undergoing bariatric surgery: A scoping review.

Attachment orientation is a psychological factor concerning our expectations of ourselves and others in interpersonal relationships. An emerging literature has suggested that attachment orientation may influence a range of outcomes associated with bariatric surgery. The purpose of this scoping review was to map the literature and examine the role of attachment orientation in the context of bariatric surgery. Studies conducted with patients who are undergoing or have undergone bariatric surgery, with a measure of attachment orientation and published by 21st July 2019, were located through electronic searches including Scopus, PubMed and Web of Science. 21180 studies were identified, of which 18 were retained for narrative synthesis. The major outcome themes reported were (1) post-surgery weight-loss/body mass index (k = 10), (2) eating behaviour (k = 9), (3) attachment orientation differences in bariatric surgery patients compared with control groups (k = 4) and 4) other mental and physical health outcomes (k = 12). Overall, the results showed that there was little evidence to suggest that poor attachment orientation is predictor of weight-loss following surgery. There was evidence to suggest that poorer attachment orientation relates to poorer eating behaviours both before and after surgery, that patients undergoing bariatric surgery are more likely to have a poorer attachment orientation and attachment orientation is related to mental health outcomes but not physical health outcomes for patients. However, where relationships were identified, there were considerable inconsistencies regarding the dimension of attachment orientation that drove the relationship. Future studies should consider appropriate sample sizes for studies, replication of key findings and longer durations for longitudinal studies.

Cerebrospinal fluid diversion versus bariatric surgery in the management of idiopathic intracranial hypertension.

Background: Idiopathic intracranial hypertension (IIH) is a condition affecting predominantly young women with increased body mass index (BMI). Obesity with the related metabolic and biochemical complications are thought to be involved in the pathogenesis of the condition. The aim of this study is to evaluate the safety, outcomes and economic implications of two treatment options for IIH.Methods: We retrospectively analysed cases of morbidly obese IIH patients treated by cerebrospinal fluid (CSF) shunting procedures between 2006 and 2016 in our department and compared their outcome with that of 69 patients undergoing bariatric surgery between 2015 and 2016.Results: A total of 42 female patients with IIH underwent de-novo shunting procedures during the study period. There was a high rate of shunt revisions (67%) and further weight gain in the majority of patients who had the insertion of CSF shunts. Of the 69 female patients undergoing bariatric surgery 4.3% required interventions related to their surgery with a significantly fewer number of hospital inpatient days. Furthermore, in the patients undergoing bariatric surgery, there was a significant improvement in all obesity-related complications.Conclusions: CSF shunting procedures do not address the aetiological factor of IIH and are associated with high rates of morbidity and further weight gain. Bariatric surgery is not only efficacious in the management of patients with IIH but is associated with significant improvements in other obesity-related comorbidities. Bariatric surgery is safe and more cost-effective than CSF shunting.

Closure of mesenteric defects during Roux-en-Y gastric bypass for obesity: A systematic review and meta-analysis protocol.

INTRODUCTION: Closure of mesenteric defects during laparoscopic Roux-en-Y gastric bypass surgery (RYGB) has not been fully established as standard operative practice. However, in recent years a body of evidence has emerged suggesting that non-closure of defects leads to increased rates of internal herniation and its potential consequences, including the need for reoperation, along with an associated morbidity and mortality risk. Within the emerging literature there has also been some evidence of a greater risk of 30-day complications in closure groups. This systematic review and meta-analysis aims to look at the existing evidence and provide guidance on whether closure of mesenteric defects should be standard operative practice. METHODS: The systematic review and meta-analysis has been registered a priori. A literature search will be performed interrogating the Medline and Embase databases via Ovid, and also the Cochrane Controlled Register of Trials (CENTRAL), to identify randomised and non-randomised studies reporting comparative outcomes following closure vs. non-closure of mesenteric defects during RYGB. The primary outcome will be reoperation for small bowel obstruction, and secondary outcomes will include internal herniation, jejuno-jejunal anastomosis narrowing or kinking, adhesions, complications (<30 days and >30 days after surgery), 30-day mortality, reoperation, and any other outcome deemed relevant and reported in more than one study.

Temporal effects of laparoscopic sleeve gastrectomy on adipokines, inflammation, and oxidative stress in patients with impaired glucose homeostasis.

BACKGROUND: Bariatric surgery is an effective treatment for morbid obesity and metabolic dysfunction. OBJECTIVES: The aim of this work was to examine the early temporal effects of laparoscopic sleeve gastrectomy (LSG) on adipokines (adiponectin, leptin), inflammatory cytokines (interleukin-6, C-reactive protein, interleukin-10), and global plasma measures of oxidative stress (thiobarbituric acid reactive substances and total antioxidant status) in a sample of 55 participants preoperatively, and 1 and 6 months postoperatively. The focus was on a sample of patients with impaired glucose tolerance and type 2 diabetes, which is associated with increased low-grade systemic inflammation and oxidative stress. SETTING: University hospital, United Kingdom. METHODS: This was a prospective study comprising 55 participants with impaired glucose homeostasis and type 2 diabetes undergoing LSG (mean body mass index 50.4 kg/m2, mean glycated hemoglobin 7.4%). Serial measurements of the above markers were made preoperatively, 1 and 6 months postoperatively (43 had measurable cytokines and oxidative stress at 1- and 6-mo follow-up). RESULTS: We observed a significant reduction in interleukin-6, C-reactive protein, leptin, and thiobarbituric acid reactive substances, along with an increase in adiponectin 6 months postoperatively. CONCLUSIONS: To our knowledge the effects of LSG on inflammatory cytokines and plasma markers of oxidative stress have not been examined temporally in a sizeable sample of participants who have undergone LSG. This present study supports the role of LSG for the treatment of the proinflammatory and pro-oxidant status associated with obesity-related glucose dysregulation.

Educating physicians in seventeenth-century England - ADDENDUM.

The tension between theoretical and practical knowledge was particularly problematic for trainee physicians. Unlike civic apprenticeships in surgery and pharmacy, in early modern England there was no standard procedure for obtaining education in the practical aspects of the physician's role, a very uncertain process of certification, and little regulation to ensure a suitable reward for their educational investment. For all the emphasis on academic learning and international travel, the majority of provincial physicians returned to practice in their home area, because establishing a practice owed more to networks of kinship, patronage and credit than to formal qualifications. Only when (and where) practitioners had to rely solely on their professional qualification to establish their status as young practitioners that the community could trust would proposals to reform medical education, such as those put forward to address a crisis of medicine in Restoration London, which are examined here, be converted into national regulation of medical education in the early nineteenth century, although these proposals prefigured many informal developments in medical training in the eighteenth century.

The 'Compleat Physician' and Experimentation in Medicines: Everard Maynwaring (c.1629-1713) and the Restoration Debate on Medical Practice in London.

Restoration London saw a wave of publications by physicians advocating that the 'compleat physician' should be one who experimented and produced his own medicines. Only thus, they argued, could the medical hierarchy be restored and medical authority re-established on a defensible basis. This article seeks to explain the context for this unusual approach, and why it failed to attract mainstream physicians by the end of the century, by considering the sixty-year career of one of its leading advocates, Everard Maynwaring (c.1629-1713), a prolific medical author, and what his own failure to enter the medical establishment may show about the problems inherent in this model for the physician. A university-trained gentleman physician who converted to chymical medicine c.1660, Maynwaring published learned and relatively unpolemical texts to persuade both medical and lay audiences of the superiority of experimental medicine as a mode of learned practice, yet could not easily reconcile this with the advocacy and sale of his own chymical medicines (especially as he focused increasingly on a small group of 'universal medicines') without being branded an 'empirick'. Fragmentary evidence regarding his career suggests he became increasingly marginalised, and as an old man was reduced to advertising his cures like the 'empiricks' from whom he had sought to distance both himself and physicians in general.

John Houghton and Medical Practice in London c. 1700.

This article considers the evidence for medical practice in London c. 1700 provided by A Collection for the Improvement of Husbandry and Trade (1692-1703) by the apothecary and Fellow of the Royal Society, John Houghton (1645-1705). Houghton discusses how products are used medicinally, as well as the necessary qualifications for a physician, and reports his own experiments and health experiences. His advertisements reveal the range of (largely medical) products he could himself supply, but he also offered an information service, often for medical practitioners, throwing light on both the supply and demand for medical practitioners in different communities and the desirable attributes of shops. Whereas most sources used to uncover medical practice highlight conflict and competition, Houghton's approach emphasizes consensus and cooperation, partly for his own ideological and commercial reasons, and partly reflecting the emergence of new forms of medical practice supported by the new science and by genteel consumer demand.

Temporal changes in plasma markers of oxidative stress following laparoscopic sleeve gastrectomy in subjects with impaired glucose regulation.

BACKGROUND: Laparoscopic sleeve gastrectomy (LSG) is an effective treatment for obesity and associated metabolic complications. Obesity and type 2 diabetes are associated with increased oxidative stress. Previous studies have examined changes in plasma oxidative stress after laparoscopic Roux-en-Y gastric bypass, but there is limited evidence of the effects of LSG. OBJECTIVES: To examine the effects of LSG on plasma thiobarbituric acid reactive substances (TBARS) and total antioxidant status (TAOS) at 1 and 6 months after LSG in patients with obesity and impaired glucose regulation. SETTING: University hospital, United Kingdom. METHODS: Twenty-two participants with impaired glucose homeostasis undergoing LSG (body mass index 50.1 kg/m2, glycated hemoglobin 53 mmol/mol) were studied. Measurements of fasting and 120-minute TBARS and TAOS were performed during an oral glucose tolerance test preoperatively and postoperatively. RESULTS: Compared with preoperative levels, significant decreases were seen 6 months postoperatively in fasting TBARS (61.0±17.9 versus 39.4±13.8 ng/mL, P = .04) and 120-minute TBARS (76.0±29.5 versus 46.5±16.3 ng/mL, P = .02). No significant changes were observed in plasma TAOS. No significant association was observed between changes in TBARS and other clinical or biochemical measures. CONCLUSION: We observed a significant reduction in TBARS, a global measure of lipid peroxidation 6 months after LSG in participants with obesity and impaired glucose regulation.

Temporal Effect of Bariatric Surgery on Predicted 10-Year and Lifetime Cardiovascular Risk at 1 Month, 6 Months, and 5 Years Following Surgery: A Pilot Study.

BACKGROUND AND AIMS: Cardiovascular (CV) risk equations are routinely used to predict risk in nonbariatric populations, but have not been studied in depth in patients undergoing bariatric surgery and specifically those with impaired glucose regulation. The aim of this pilot study was to investigate changes in the 10-year and lifetime predicted CV risk in subjects with impaired glucose regulation before, 1 month, 6 months, and 5 years after bariatric surgery. METHOD AND RESULTS: A nonrandomized prospective study was conducted of 45 participants with impaired glucose regulation undergoing temporal assessments during follow-up. Body weight, body mass index (BMI), blood pressure, lipid profile, and HbA1c were recorded preoperatively, 1 month, 6 months, and 5 years postoperatively. Preoperative and postoperative predicted CV risk was calculated using the QRISK2, QRISK lifetime, and JBS3 calculators. Follow-up rates were 93%, 91%, and 71% at 1 month, 6 months, and 5 years, respectively. The sample had a mean age of 48.8 ± 7.0 years, a mean BMI of 53.9 ± 11.1 kg/m2, and a mean HbA1c of 7.5% ± 1.7%. The predicted 10-year QRISK2 score decreased by 35%, 54%, and 24% at 1 month, 6 months, and 5 years, respectively (P < 0.001). The predicted lifetime risk also decreased with the greatest reduction (24.5% with QRISK lifetime and 26.7% with JBS3 lifetime score) observed at 5 years even though the subjects were 5 years older. CONCLUSION: Bariatric surgery in patients with impaired glucose regulation is associated with a significant reduction in predicted 10-year and lifetime CV risk in a population that was 5 years older compared to baseline.

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.

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.

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.

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.

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.

Snapshots in surgery: small bowel intussusception following ileojejunal bypass.

KEY CLINICAL MESSAGE: Jejunal intussusception is a known complication of ileojejunal bypass surgery for obesity that may present as an acute abdomen. It can be avoided if the jejunum is anchored to the transverse mesocolon intra-operatively.

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.