Bariatric surgery and hypertension

Long Biliopancreatic Limb Roux-En-Y Gastric Bypass Versus One-Anastomosis Gastric Bypass: a Randomized Controlled Study

BACKGROUND

Roux-en-Y gastric bypass (RYGB) is the gold standard in bariatric surgery. The one-anastomosis gastric bypass (OAGB) procedure, first introduced by Dr. Rutledge, has demonstrated a 25% greater weight loss efficiency than the traditional Roux-en-Y gastric bypass (RYGB) procedure due to the substantially longer biliopancreatic limb (BPL).

AIM OF THE STUDY

The current work aimed to compare the outcomes of OAGB and long BPL RYGB regarding weight loss and comorbidity resolution.

PATIENTS AND METHODS

This randomized controlled trial was done at our institution between September 2019 and January 2021. Patients who were candidates for bariatric surgery were randomly and equally allocated to two groups. Group A underwent OAGB, while group B underwent long BPL RYGB. Patients were followed up for 6 months postoperatively.

RESULTS

This study included 62 patients equally allocated to OAGB or long BPL RYGB, with no dropouts during follow-up. At 6 months, there was no statistically significant difference between the two groups regarding postoperative BMI (P = 0.313) and the EBWL (P = 0.238). There was comparable remission of diabetes mellitus (P = 0.708), hypertension (P = 0.999), OSA (P = 0.999), joint pain (P = 0.999), and low back pain (P = 0.999). Seven patients in the OAGB group experienced reflux symptoms (P = 0.011), which were managed by proton pump inhibitors.

CONCLUSION

Extending the BPL in RYGB provides weight loss and comorbidity remission comparable to that of OAGB. Some OAGB-related reflux cases remain a concern. However, they were sufficiently controlled with PPIs. Due to OAGB superior technical simplicity, long BPL RYGB should be preserved for cases whom are more risky for bile reflux.

Effect of bariatric surgery on maternal cardiovascular system

OBJECTIVE

Bariatric surgery is a successful treatment for sustainable weight loss and has been associated with improvement in cardiovascular function. Pregnancy after bariatric surgery is becoming increasingly common; however, little is known about the maternal cardiovascular system postsurgery. The aim of this study was to investigate maternal cardiovascular adaptation to pregnancy in women with previous bariatric surgery, compared with that in women with no history of weight-loss surgery and an early-pregnancy body mass index (BMI) similar to the presurgery BMI of the postbariatric women.

METHODS

This was a prospective, observational, longitudinal study conducted from April 2018 to June 2020 including 30 pregnant women who had undergone bariatric surgery and 30 who had not, matched for presurgery BMI. Participants were seen at three timepoints during pregnancy: 12-14, 20-24 and 30-32 weeks' gestation. At all visits, maternal blood pressure (BP) was measured and cardiac geometry and function were assessed using two-dimensional (2D) transthoracic echocardiography. On a subset of patients (15 in each group), 2D speckle tracking was performed to assess global longitudinal and circumferential strain. Offline analysis was performed, and multilevel linear mixed-effects models were used for all comparisons.

RESULTS

Compared with the no-surgery group, and across all trimesters, pregnant women with previous bariatric surgery had lower BP, heart rate and cardiac output and higher peripheral vascular resistance (P < 0.01 for all). Similarly, the postbariatric group demonstrated more favorable cardiac geometry and diastolic indices, including lower left ventricular mass, left atrial volume and relative wall thickness, together with higher E-wave/A-wave flow velocity across the mitral valve and higher mitral velocity (E') at the lateral and medial annulus on tissue Doppler imaging (P < 0.01 for all). There was no difference in ejection fraction, although global longitudinal strain was lower in postbariatric women (P < 0.01), indicating better systolic function.

CONCLUSION

Our findings indicate better maternal cardiovascular adaptation in women with previous bariatric surgery compared with presurgery BMI-matched pregnant women with no history of weight-loss surgery. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Bariatric surgeries: Outcome throughout an annum at a specialist center in Malaysia

INTRODUCTION

Malaysia has the highest number of obese and overweight individuals in South-east Asia. The 2019 National Health & Morbidity survey found 50.1% of Malaysians to be overweight or obese with 30.4% being overweight and 19.7% being obese. This has led to the high rise of the bariatric surgeries demand and needs within the nation.

AIM & OBJECTIVES

To assess the level of fasting blood sugar (FBS), systolic, diastolic blood pressure, stop BANG score for obstructive sleep apnoea (OSA) and BMI (Body Mass Index) for the patients before and after bariatric surgeries (sleeve/gastric bypass) for a one year follow up period.

MATERIAL & METHODS

The study was conducted among 1000 patients who underwent a single weight reduction surgery (sleeve/gastric bypass) by a single surgeon at the Cengild Medical Centre between January 2019 to January 2020. They were followed up for a one-year period through recording the parameters of fasting blood sugar (FBS), systolic, diastolic blood pressure, stop BANG score for obstructive sleep apnoea (OSA) and BMI (Body Mass Index). Study was conducted using universal sampling including all subjects visited the centre and a written consent was obtained from each participant. Descriptive statistics with mean was used and paired t-test was used for comparison and test the difference. The STOP-BANG acronym stands for: Snoring history, Tired during the day, Observed stop breathing while sleep, High blood pressure, BMI more than 35 kg/m2, Age more than 50 years, Neck circumference more than 40 cm and male Gender.

RESULTS

The mean age of patients was 38 years old. Mean FBS for the patients one month before the operation was 10.42 mmol/L and 5.84 three months post procedure. The systolic blood pressure one month before the operation and 3 months after was 139.81 mmHg and 123.79 mmHg, while diastolic blood pressure was 86.84 mmHg and 81.07 mmHg respectively. BMI was reduced from 39.69 to 27.99 after one year from the weight reduction operation. All the above parameters showed a significant reduction between one-month pre operation as compared to 3 months and 12 months post operation and that improved the health parameters of the patients significantly.

CONCLUSION

The weight reduction operations showed a significant reduction in the FBS, blood pressure, OSA scores and BMI at 3, 12 months after the operation These patients had better overall health after the significant reduction in these parameters.

Bariatric Surgery and Hypertension

A clear pathogenetic association exists between obesity and arterial hypertension, becoming even more evident in subjects with severe obesity. Bariatric surgery has proved to be the most effective treatment for severe obesity, with its benefits going beyond weight loss. The present review aimed to determine the effects of bariatric surgery on arterial hypertension evident in short- and long-term follow-ups. Moreover, the differences between surgical techniques regarding hypertension remission are described as well as the possible pathophysiologic mechanisms involved. In addition, the effects of bariatric surgery beyond blood pressure normalization are also analyzed, including those on target organs and cardiovascular morbidity and mortality.

Bariatric surgery is associated with reduced admission for aortic dissection: a nationwide case-control analysis

BACKGROUND

Aortic dissection (AD) is an uncommon but life-threatening condition associated with high morbidity and mortality. Hypertension (HTN) and hyperlipidemia (HLD) are common modifiable risk factors.

OBJECTIVES

Since bariatric surgery is associated with remission of obesity-related co-morbidities, we hypothesize that surgical weight loss might be protective against this feared aortic pathology.

SETTING

A cross-sectional analysis was performed using the National Inpatient Sample database from 2010 to 2015.

METHODS

The treatment group included bariatric patients and the control group patients with obesity (body mass index [BMI] ≥ 35kg/m²) without previous bariatric surgery. Analyzed covariates included demographics, co-morbidities, aortic diseases, and AD. A multivariate logistic regression analysis (MLRA) was performed to assess the odds of admission for AD in both groups.

RESULTS

A total of 2,300,845 patients were identified (2,004,804 controls and 296,041 cases). The mean (SEM) age was 54.4 (.05) versus 51.9 (.05) years, for the control and treatment groups, respectively (P < .0001). Bariatric patients posed a significantly lower prevalence of type 2 diabetes (T2D), HTN, HLD, aortic aneurysm, and bicuspid aortic valve (P < .0001) than control subjects. In the control group, 1411 individuals (.070%) had AD, whereas only 94 patients (.032%) in the bariatric surgery group had such diagnosis (P < .0001). The MLRA showed that non-bariatric obese patients had a significantly higher likelihood of suffering from AD (OR = 1.8 [95%CI 1.44-2.29] P < .0001). Considering different age groups, bariatric surgery was found to be less associated with admission for AD for individuals below and above 40 years of age (OR = 2.95 [95%CI 1.09-7.99] P = .0345) and (OR = 1.75 [95%CI 1.38-2.22] P < .0001), respectively.

CONCLUSIONS

Bariatric surgery could be a protective factor against aortic dissection and should be considered in patients with obesity and risk factors for this cardiovascular complication.

Sleeve gastrectomy enables simultaneous pancreas and kidney transplantation in severely obese recipients

BACKGROUND

Obesity adversely affects wait-listing and precludes patients with concomitant end-stage renal disease and type 1 diabetes mellitus from getting a simultaneous pancreas and kidney transplantation (SPK).

OBJECTIVE

To analyze safety and efficacy of laparoscopic sleeve gastrectomy (LSG) before SPK in severely obese type I diabetics.

METHODS

We assessed weight curve, complications, and graft function of three patients who underwent LSG before SPK.

RESULTS

LSG was uneventful in all patients. Body mass index dropped from 38.4 (range 35.7 - 39.9) before LSG to 28.5 (26.8 - 30.9) until SPK, with a mean loss of 25.8% (22.4 - 32.3). Interval between LSG and SPK was 364.3 (173 - 587) days. Pancreas and kidney graft function was excellent, with 100% insulin-free and dialysis-free survival over a mean follow-up of 3.6 (2.9 - 4.5) years. A1C dropped from 7% (6.3 - 8.2) before LSG to 4.9% (4.7 - 5.3) and 4.8% (4.5 - 5.1) 1 and 2 years after SPK, respectively.

CONCLUSION

LSG before SPK is safe and effective to enable severely obese type I diabetics to receive a lifesaving transplant. This is the first study analyzing the role of bariatric surgery before simultaneous pancreas and kidney transplantation.

Five-Year Outcomes of Gastric Bypass in Adolescents as Compared with Adults

BACKGROUND

Bariatric surgery results in weight loss and health improvements in adults and adolescents. However, whether outcomes differ according to the age of the patient at the time of surgery is unclear.

METHODS

We evaluated the health effects of Roux-en-Y gastric bypass in a cohort of adolescents (161 patients enrolled from 2006 through 2012) and a cohort of adults (396 patients enrolled from 2006 through 2009). The two cohorts were participants in two related but independent studies. Linear mixed and Poisson mixed models were used to compare outcomes with regard to weight and coexisting conditions between the cohorts 5 years after surgery. The rates of death and subsequent abdominal operations and selected micronutrient levels (up to 2 years after surgery) were also compared between the cohorts.

RESULTS

There was no significant difference in percent weight change between adolescents (-26%; 95% confidence interval [CI], -29 to -23) and adults (-29%; 95% CI, -31 to -27) 5 years after surgery (P = 0.08). After surgery, adolescents were significantly more likely than adults to have remission of type 2 diabetes (86% vs. 53%; risk ratio, 1.27; 95% CI, 1.03 to 1.57) and of hypertension (68% vs. 41%; risk ratio, 1.51; 95% CI, 1.21 to 1.88). Three adolescents (1.9%) and seven adults (1.8%) died in the 5 years after surgery. The rate of abdominal reoperations was significantly higher among adolescents than among adults (19 vs. 10 reoperations per 500 person-years, P = 0.003). More adolescents than adults had low ferritin levels (72 of 132 patients [48%] vs. 54 of 179 patients [29%], P = 0.004).

CONCLUSIONS

Adolescents and adults who underwent gastric bypass had marked weight loss that was similar in magnitude 5 years after surgery. Adolescents had remission of diabetes and hypertension more often than adults. (Funded by the National Institute of Diabetes and Digestive and Kidney Diseases; ClinicalTrials.gov number, NCT00474318.).

Meta-analysis of the effectiveness of laparoscopic adjustable gastric banding versus laparoscopic sleeve gastrectomy for obesity

BACKGROUND

Laparoscopic adjustable gastric banding (LAGB) and laparoscopic sleeve gastrectomy (LSG) are common weight loss procedures. Our meta-analysis compared these procedures for the treatment of morbid obesity and related diseases.

METHODS

We systematically searched the PubMed, Embase, and the Cochrane Library through January 2018. The percentage of excess weight loss (%EWL), improvement or remission of type 2 diabetes mellitus (T2DM) and hypertension were analyzed and compared.

RESULTS

Thirty-three studies with 4109 patients were included. Greater decreases in excess weight were found in patients who received LSG at 6 months (weighted mean difference (WMD) -9.29, 95% confidence interval (CI): -15.19 to -3.40, P = .002), 12 months (WMD -16.67 95% CI: -24.30 to -9.05, P < .0001), 24 months (WMD -19.63, 95% CI: -29.00 to -10.26, P < .0001), and 36 months (WMD -19.28, 95% CI: -27.09 to -11.47, P < .0001) than in patients who received LAGB. However, there were no significant differences in the 3-month outcomes between the 2 groups (WMD -1.61, 95% CI: -9.96 to 6.73, P = .70). T2DM patients after LSG experience more significant improvement or remission of diabetes (odds ratio (OR): 0.22, 95% CI: 0.06-0.87, P = .03). The 2 groups did not significantly differ regarding improvement or remission of hypertension (OR 0.80, 95% CI: 0.46-1.38, P = .42).

CONCLUSION

LSG is a more effective procedure than LAGB for morbidly obese patients, contributing to a higher %EWL and greater improvement in T2DM.

Effects of Bariatric Surgery in Obese Patients With Hypertension: The GATEWAY Randomized Trial (Gastric Bypass to Treat Obese Patients With Steady Hypertension)

BACKGROUND

Recent research efforts on bariatric surgery have focused on metabolic and diabetes mellitus resolution. Randomized trials designed to assess the impact of bariatric surgery in patients with obesity and hypertension are needed.

METHODS

In this randomized, single-center, nonblinded trial, we included patients with hypertension (using ≥2 medications at maximum doses or >2 at moderate doses) and a body mass index between 30.0 and 39.9 kg/m2. Patients were randomized to Roux-en-Y gastric bypass plus medical therapy or medical therapy alone. The primary end point was reduction of ≥30% of the total number of antihypertensive medications while maintaining systolic and diastolic blood pressure <140 mm Hg and 90 mm Hg, respectively, at 12 months.

RESULTS

We included 100 patients (70% female, mean age 43.8±9.2 years, mean body mass index 36.9±2.7 kg/m2), and 96% completed follow-up. Reduction of ≥30% of the total number of antihypertensive medications while maintaining controlled blood pressure occurred in 41 of 49 patients from the gastric bypass group (83.7%) compared with 6 of 47 patients (12.8%) from the control group with a rate ratio of 6.6 (95% confidence interval, 3.1-14.0; P<0.001). Remission of hypertension was present in 25 of 49 (51%) and 22 of 48 (45.8%) patients randomized to gastric bypass, considering office and 24-hour ambulatory blood pressure monitoring, respectively, whereas no patient submitted to medical therapy was free of antihypertensive drugs at 12 months. A post hoc analysis for the primary end point considering the SPRINT (Systolic Blood Pressure Intervention Trial) target reached consistent results, with a rate ratio of 3.8 (95% confidence interval, 1.4-10.6; P=0.005). Eleven patients (22.4%) from the gastric bypass group and none in the control group were able to achieve SPRINT levels without antihypertensives. Waist circumference, body mass index, fasting plasma glucose, glycohemoglobin, low-density lipoprotein cholesterol, triglycerides, high-sensitivity C-reactive protein, and 10-year Framingham risk score were lower in the gastric bypass than in the control group.

CONCLUSIONS

Bariatric surgery represents an effective strategy for blood pressure control in a broad population of patients with obesity and hypertension.

CLINICAL TRIAL REGISTRATION

URL: https://clinicaltrials.gov. Unique identifier: NCT01784848.

Panniculectomy Combined with Bariatric Surgery by Laparotomy: An Analysis of 325 Cases

Surgical treatment of obese patients is much debated in the literature because of the significant intraoperative risks related to comorbidities presented by this type of patients. Recent literature suggests that panniculectomy should follow bariatric surgery after the patient's weight loss has been stabilized. However, when performed by laparotomy, bariatric surgery can be combined with panniculectomy. This paper presents the analysis of 325 cases of patients undergoing abdominal panniculectomy combined with bariatric surgery. The study highlights the risks, complications, and benefits of the combined procedure and describes a standardized technique for excision of a large abdominal panniculus in a short operating time.

Ileal transposition surgery produces ileal length-dependent changes in food intake, body weight, gut hormones and glucose metabolism in rats

BACKGROUND

Enhanced stimulation of the lower gut is hypothesized to play a key role in the weight loss and resolution of diabetes following bariatric surgeries. Ileal transposition (IT) permits study of the effects of direct lower gut stimulation on body weight, glucose homeostasis and other metabolic adaptations without the confounds of gastric restriction or foregut exclusion. However, the underlying mechanisms and the length of the ileum sufficient to produce metabolic benefits following IT surgery remain largely unknown.

OBJECTIVE

To determine the effects of transposing varying lengths of the ileum to upper jejunum on food intake, body weight, glucose tolerance and lower gut hormones, and the expression of key markers of glucose and lipid metabolism in skeletal muscle and adipose tissue in rats.

METHODS

Adult male Sprague-Dawley rats (n=9/group) were subjected to IT surgery with translocation of 5, 10 or 20 cm of the ileal segment to proximal jejunum or sham manipulations. Daily food intake and body weight were recorded, and an intraperitoneal glucose tolerance test was performed. Blood samples were assayed for hormones and tissue samples for mRNA (RT-qPCR) and/or protein abundance (immunoblotting) of regulatory metabolic markers.

RESULTS

We demonstrate that IT surgery exerts ileal length-dependent effects on multiple parameters including: (1) decreased food intake and weight gain, (2) improved glucose tolerance, (3) increased tissue expression and plasma concentrations of glucagon-like peptide-1 (GLP-1) and peptide YY (PYY), and decreased leptin concentrations and (4) upregulation of key markers of glucose metabolism (glucose transporter-4 (GLUT-4), insulin receptor substrate 1 (IRS-1), adenosine monophosphate-activated protein kinase (AMPK), hexokinase (HK) and phosphofructokinase (PFK)) together with a downregulation of lipogenic markers (fatty acid synthase (FAS)) in muscle and adipose tissue.

CONCLUSIONS

Together, our data demonstrate that the reduction in food intake and weight gain, increase in lower gut hormones, glycemic improvements and associated changes in tissue metabolic markers following IT surgery are dependent on the length of the transposed ileum.

Effects of sleeve gastrectomy and ileal transposition, alone and in combination, on food intake, body weight, gut hormones, and glucose metabolism in rats

Bariatric surgeries are hypothesized to produce weight loss and improve diabetes control by multiple mechanisms including gastric restriction and lower gut stimulation; the relative importance of these mechanisms remains poorly understood. We compared the effects of a typical foregut procedure, sleeve gastrectomy, (SG) with a primarily hindgut surgery, ileal transposition (IT), alone and together (SGIT), or sham manipulations, on food intake, body weight, gut hormones, glucose tolerance, and key markers of glucose homeostasis in peripheral tissues of adult male Sprague-Dawley rats (450-550 g, n = 7-9/group). SG, IT, and SGIT surgeries produced transient reduction in food intake and weight gain; the effects of SG and IT on intake and body weight were nonadditive. SG, IT, and SGIT surgeries resulted in increased tissue expression and plasma concentrations of the lower gut hormones glucagon-like peptide-1 and peptide YY and decreased plasma glucose-dependent insulinotropic peptide, insulin, and leptin concentrations. Despite transient effects on intake and weight gain, the SG, IT, and SGIT surgeries produced a significant improvement in glucose tolerance. In support of glycemic improvements, the protein abundance of key markers of glucose metabolism (e.g., GLUT4, PKA, IRS-1) in muscle and adipose tissue were increased, whereas the expression of key gluconeogenic enzyme in liver (G-6-Pase) were decreased following the surgeries. Therefore, our data suggest that enhanced lower gut stimulation following SG, IT, and SGIT surgeries leads to transient reduction in food intake and weight gain together with enhanced secretion of lower gut hormones and improved glucose clearance by peripheral tissues.

Predictors for remission of major components of the metabolic syndrome after biliopancreatic diversion with duodenal switch (BPDDS)

BACKGROUND

Metabolic surgery causes the remission of type 2 diabetes mellitus (T2DM), hypertension, and hyperlipidemia to varying degrees, depending on the patient characteristics and the surgical procedure. The aim of this study was to find predictors for the remission of T2DM and hypertension after biliopancreatic diversion with duodenal switch (BPDDS).

METHODS

Eighty patients with T2DM were followed up for 2 years or more after BPDDS, and changes in body weight and metabolic status were noted. Remission was defined as fasting glucose <7 mmol/l with HbA1C <6.5 %, blood pressure <140/90 mmHg, and low-density lipoprotein (LDL) <2.6 mmol without the use of medication.

RESULTS

Preoperatively, the mean age was 44 years, body mass index (BMI) was 48 kg/m(2), and duration of diabetes was 5 years. Of the 80 patients, 38 patients were using insulin, 48 patients were using antihypertensives, and 38 patients were using a lipid-lowering drug. Five percent of the patients had recommended levels for HbA1C, blood pressure, and LDL prior to the operation. The remission rate at 2 years was 94 % for T2DM, 54 % for hypertension, and 86 % for LDL hyperlipidemia. Preoperative predictors for nonremission of T2DM were a higher BMI, insulin usage, and low insulin C-peptide, and for hypertension, older age and more severe hypertension. Postoperative weight loss was important for both.

CONCLUSIONS

Surgical intervention with BPDDS is an effective treatment of T2DM, hypertension, and hyperlipidemia. The duration of T2DM and age of the patient are the most important preoperative predictors for the remission of T2DM and hypertension, respectively.

Obesity-related hypertension and its remission following gastric bypass surgery - a review of the mechanisms and predictive factors

It is well established that hypertension and obesity appear to be associated. The exact mechanism by which they are linked is unclear and remains a topic of a great deal of research. Current NICE guidelines recommend that patients with a BMI in excess of 35 kg/m(2) should be considered for bariatric surgery if they have a concomitant obesity-associated condition, of which hypertension is one. The commonest bariatric procedure in the UK is the Roux-en-Y gastric bypass, which has been shown to result in long-standing remission of hypertension in up to 93% of patients. This paper summarizes the existing literature on the main theories as to how obesity leads to hypertension as well as the literature concerning the effects of gastric bypass surgery on hypertension.

Alveolar bone loss and periodontal status in a bariatric patient: a brief review and case report

To review the effects of obesity surgery on oral health and to present a case report of the periodontal condition of an obese woman who underwent bariatric surgery. A search of studies related to bariatric surgery and oral health was made in PubMed. For case report, BMI, salivary flow, and periodontal condition were evaluated during three different periods. The oral health problems found were dental wear, periodontal diseases, xerostomia, and dental caries. The patient who was evaluated before bariatric surgery and was followed up for 2 years, lost 40.4 kg, presented normal blood glucose levels and controlled hypertension without medication. Salivary flow remained of equal value in the first year, there was an increase in mean probing depth and there existed low bone density in these sites. Patients who have undergone bariatric surgery need to be closely monitored after surgery to prevent the development of oral complications, especially periodontal conditions.

Advances in the etiology and management of hyperinsulinemic hypoglycemia after Roux-en-Y gastric bypass

INTRODUCTION

Hyperinsulinemic hypoglycemia with severe neuroglycopenia has been identified as a late complication of Roux-en-Y gastric bypass (RYGB) in a small number of patients.

DISCUSSION

The rapid resolution of type 2 diabetes mellitus after RYGB is probably related to increased secretion of the incretin hormones glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1), and patients with post-RYGB hypoglycemia demonstrate prolonged elevations of GIP and GLP-1 compared to non-hypoglycemic post-RYGB patients. Nesidioblastosis has been identified in some patients with post-RYGB hypoglycemia and is likely due to the trophic effects of GIP and GLP-1 on pancreatic islets.

CONCLUSIONS

Treatment of hypoglycemia after RYGB should begin with strict dietary (low carbohydrate) alteration and may require a trial of diazoxide, octreotide, or calcium-channel antagonists, among other drugs. Surgical therapy should include consideration of a restrictive form of bariatric procedure, with or without reconstitution of gastrointestinal continuity. Partial or total pancreatic resection should be avoided.

Diabetes resolution and hyperinsulinaemia after metabolic Roux-en-Y gastric bypass

The global prevalence of type 2 diabetes mellitus and impaired glucose metabolism continues to rise in conjunction with the pandemic of obesity. The metabolic Roux-en-Y gastric bypass operation offers the successful resolution of diabetes in addition to sustained weight loss and excellent long-term outcomes in morbidly obese individuals. The procedure consists of the physiological BRAVE effects: (i) Bile flow alteration; (ii) Reduction of gastric size; (iii) Anatomical gut rearrangement and altered flow of nutrients; (iv) Vagal manipulation and (v) Enteric gut hormone modulation. This operation provides anti-diabetic effects through decreasing insulin resistance and increasing the efficiency of insulin secretion. These metabolic outcomes are achieved through weight-independent and weight-dependent mechanisms. These include the foregut, midgut and hindgut mechanisms, decreased inflammation, fat, adipokine and bile metabolism, metabolic modulation, shifts in gut microbial composition and intestinal gluconeogenesis. In a small minority of patients, gastric bypass results in hyperinsulinaemic hypoglycaemia that may lead to nesidioblastosis (pancreatic beta-cell hypertrophy with islet hyperplasia). Elucidating the precise metabolic mechanisms of diabetes resolution and hyperinsulinaemia after surgery can lead to improved operations and disease-specific procedures including 'diabetes surgery'. It can also improve our understanding of diabetes pathogenesis that may provide novel strategies for the management of metabolic syndrome and impaired glucose metabolism.

Metabolic surgery: an evolution through bariatric animal models

Metabolic surgery was developed through the application and experience gained from bariatric or weight loss procedures. Much of our knowledge from the procedures comes from the study of animal models, where they have revealed anatomic feasibility, systemic physiological elements and cellular metabolic effects. The first generation of operation included the jejunoileal bypass and partial ileal bypass that led to the development of the current procedures including Roux-en-Y gastric bypass, biliopancreatic diversion, adjustable gastric banding and sleeve gastrectomy. These operations carry significant metabolic benefits and can reduce the risk of diabetes, heart disease and cancer. Further insights from these animal models can reveal genetic, molecular and systemic effects that can enhance and develop the next generation of metabolic operations.

Renal cytokines improve early after bariatric surgery

Background

Bariatric surgery has been suggested to improve arterial hypertension and renal function. This prospective controlled observational study aimed to investigate changes in renal inflammation, renal function and arterial blood pressure before and after bariatric surgery.

Methods

Blood pressure was measured, and urine and blood samples were collected from 34 morbidly obese patients before and 4 weeks after bariatric surgery. Serum levels of cystatin C, creatinine, albumin, cholesterol and C-reactive protein (CRP) were measured, along with urinary cytokine/creatinine ratios for macrophage migration inhibitory factor (MIF), monocyte chemotactic protein (MCP) 1, chemokine ligand (CCL) 18 and CCL-15.

Results

Mean(s.e.m.) bodyweight dropped from 124·1(2·6) to 114·8(2·4) kg (P &lt; 0·001) and mean arterial blood pressure decreased from 105·7(1·8) to 95·5(1·2) mmHg (P &lt; 0·001) in 4 weeks. Systemic and urinary inflammatory markers improved, with a reduction in serum CRP level (P &lt; 0·001), and decreased urinary MIF/creatinine (P &lt; 0·001), MCP-1/creatinine (P &lt; 0·001) and CCL-18/creatinine (P = 0·003) ratios. In contrast, urinary CCL-15/creatinine ratios did not change and the glomerular filtration rate, measured by serum cystatin C, was unchanged (P = 0·615).

Conclusion

Surgically induced weight loss contributed to a decrease in blood pressure and markers of renal inflammation. The reduced levels of CRP and urinary cytokines suggest that bariatric surgery attenuates systemic and renal inflammatory status.