Sleeve gastrectomy and Roux-en-Y gastric bypass are equally effective in correcting insulin resistance

The Effects of Bariatric Surgery on Pharmacokinetics of Drugs: a Review of Current Evidence

PURPOSE OF REVIEW

Obesity constitutes a major public health concern and has been recognized as an epidemic. To date, bariatric surgery remains the most effective way for substantial long-lasting weight loss in severe obesity. The purpose of this review is to summarize how the pharmacokinetics of drugs are affected by the most common types of bariatric surgery, i.e., Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG).

RECENT FINDINGS

Limited data are available regarding the changes in pharmacokinetics of drugs after bariatric surgery. The lack of existing guidelines may lead patients to experience drug toxicity or therapeutic undertreatment. Pharmacokinetic parameters that need to be taken into consideration postoperatively include gastric motility, gastric volume, pH, surface area, bile secretions, carrier proteins, and first-pass metabolism. For drugs with a narrow therapeutic index, other factors need to be monitored closely, including plasma drug levels, patients' clinical outcomes, and laboratory markers. Patients should be followed up frequently and treated in accordance with their response to the drug therapy. Bariatric surgery may affect the pharmacokinetics of various drugs, due to the resultant anatomical changes and the substantial weight loss. Therefore, there is a need to identify those potential changes and adjust patients' medication doses in order to achieve higher efficacy and avoid toxicity.

The Effects of Laparoscopic Sleeve Gastrectomy (LSG) on Obesity-Related Type 2 Diabetes Mellitus: a Prospective Observational Study from a Single Center

PURPOSE

The objective of the study is to evaluate the effects of laparoscopic sleeve gastrectomy (LSG) on mid- to long-term regulation of blood glucose in patients with obesity and type 2 diabetes mellitus (T2DM) MATERIALS AND METHODS : In this prospective and observational single-center study, a total of 234 patients with obesity and a diagnosis of T2DM who underwent LSG between 2015 and 2020 were evaluated. The demographics and laboratory data, consisting of body mass index (BMI), glycosylated hemoglobin (HbA1c%), and fasting plasma glucose (FPG) and total weight loss (TWL%), were compared preoperative and postoperative at 12th and 18th months and annual follow-up for seven consecutive years.

RESULTS

The mean age of 234 patients (female(n)/male(n):191/43) included in the study was 44.69±9.72 years, while the preoperative mean BMI, FPG, and HbA1c values were 47.9±6.82, 132.09±42.84 mg/dl, and 7.02±1.35% respectively. The mean rate of weight loss (TWL%), which was 34.7 in the 18 months, decreased to 23.15 in the 7th year. While the HbA1c % value was 7.02±1.35 in the preoperative, it was found 5.71 ± 0.75 (p<0.001) and 6.30 ± 1.77 (p<0.05) at the 18th month and 7th year after the operation, respectively. While the DM remission rate was 71.1% at the postoperative 18th month, it was 45.4% at the 7th year, despite the patients regaining weight in the follow-ups.

CONCLUSIONS

Our study revealed that LSG resulted in high remission rates that continued for 7 years after the surgery, although sustained improvement or remission of diabetes despite some weight regain after the first 18 months.

Insulin Resistance Remission Following Laparoscopic Roux-en-Y Gastric Bypass and Laparoscopic Sleeve Gastrectomy in Chinese Type 2 Diabetes Mellitus Patients With a Body Mass Index of 27.5-32.5 kg/m2

Background: Insulin resistance (IR) is closely associated with the pathogenesis of type 2 diabetes mellitus (T2DM). However, remission of insulin sensitivity after bariatric surgery in patients with T2DM and a body mass index (BMI) of 27.5–32.5 kg/m² has not been fully elucidated.

Methods: Thirty-six T2DM patients with a BMI of 27.5–32.5 kg/m² were prospectively consecutively recruited for laparoscopic Roux-en-Y gastric bypass (LRYGB) or laparoscopic sleeve gastrectomy (LSG). Hyperinsulinemic euglycemic clamp, oral glucose tolerance test (OGTT), and other indicators were tested at baseline and 6 months postoperative. Glucose disposal rate (GDR), time to reach euglycemia, homeostatic model assessment of IR, quantitative insulin sensitivity check index (QUICKI), triglyceride glucose (TyG) index, 30-min insulinogenic index (IGI30), and disposition index (DI) were calculated at baseline and 6 months after surgery. The criterion for remission in T2DM patients was the achievement of the triple composite endpoint.

Results: Anthropometric and glucolipid metabolism parameters significantly improved following surgery. The GDR increased significantly from baseline to 6 months after LRYGB (from 4.28 ± 1.70 mg/kg/min to 8.47 ± 1.89 mg/kg/min, p < 0.0001) and LSG (from 3.18 ± 1.36 mg/kg/min to 7.09 ± 1.69 mg/kg/min, p < 0.001). The TyG index decreased after surgery (RYGB group, from 9.93 ± 1.03 to 8.60 ± 0.43, p < 0.0001; LSG group, from 10.04 ± 0.79 to 8.72 ± 0.65, p = 0.0002). There was a significant reduction in the IGI30 (RYGB group, from 2.04 ± 2.12 to 0.83 ± 0.47, p = 0.005; LSG group, from 2.12 ± 1.73 to 0.92 ± 0.66, p = 0.001). The mean DI significantly increased from 1.14 ± 1.35 to 7.11 ± 4.93 in the RYGB group (p = 0.0001) and from 1.25 ± 1.78 to 5.60 ± 4.58 in the LSG group (p = 0.003). Compared with baseline, HOMR-IR, QUICKI, area under the curve-C-peptide release test (AUC-CRT), and AUC-OGTT were significantly changed at 6 months postoperative. Overall, 52.63% of patients in the LRYGB group versus 29.41% of patients in the LSG group achieved the triple composite endpoint.

Conclusion: Both LRYGB and LSG effectively induced remission of IR in patients with T2DM and a BMI of 27.5–32.5 kg/m².

Determinants of type 2 diabetes remission after bariatric surgery in obese Japanese patients: a retrospective cohort study

Objective

Bariatric surgery (BS) improves glycemic control in type 2 diabetes; however, some patients show insufficient improvement. Understanding the pathophysiology of type 2 diabetes in obese patients can facilitate appropriate treatment for type 2 diabetes after BS. The homeostatic model assessment (HOMA) 2 enables the calculation of the values from C-peptide data and evaluation of insulin users. We aimed to evaluate the pathophysiology of type 2 diabetes using pre- and postoperative parameters and HOMA2 in obese patients who underwent BS.

Methods

We retrospectively reviewed data from 45 obese patients with type 2 diabetes who underwent BS. They were followed-up for 12 months. The relationship between the HOMA2 score and complete remission (CR) of type 2 diabetes after BS was analyzed. Patients with and without CR were assigned to the CR and non-CR groups, respectively. Multiple regression analysis was used to identify factors associated with improvement in type 2 diabetes after BS.

Results

BS significantly improved body weight and glucose metabolism. The preoperative glycosylated hemoglobin A1c level and insulin secretion (HOMA2-%B) significantly differed between the CR and non-CR groups. Postoperative weight reduction and improved insulin sensitivity correlated significantly with CR; multiple regression showed that the preoperative HOMA 2-%B independently predicted CR of type 2 diabetes after BS.

Conclusion

Preoperative insulin secretion, improvement in insulin sensitivity, and weight reduction after BS are related to CR of type 2 diabetes after BS. The results better reveal the pathophysiology of and treatment for type 2 diabetes in obese patients who undergo BS.

Bariatric surgery improves metabolic and nonalcoholic fatty liver disease markers in metabolically healthy patients with morbid obesity at 5 years

BACKGROUND

No studies have evaluated the effect of metabolic and bariatric surgery (MBS) on nonalcoholic fatty liver disease (NAFLD) and cardiometabolic markers in metabolically healthy patients with morbid obesity (MHMO) at midterm.

OBJECTIVES

To assess the effect of MBS on NAFLD and cardiometabolic markers in MHMO patients and ascertain whether metabolically unhealthy patients with morbid obesity (MUMO) remain metabolically healthy at 5 years after MBS.

SETTING

University hospital.

METHODS

A total of 191 patients with a body mass index >40 kg/m² and at least 5 years of follow-up were retrospectively analyzed. Lost to follow-up were 37.6% (151 of 401 patients). Patients were classified as MHMO if 1 or 0 of the cardiometabolic markers were present using the Wildman criteria. The degree of liver fibrosis was assessed using the NAFLD fibrosis score (NFS).

RESULTS

Forty-one patients (21.5%) fulfilled the criteria for MHMO. They showed significant improvements in blood pressure (from 135.1 ± 22.1 and 84.2 ± 14.3 mm Hg to 117.7 ± 19.2 and 73.0 ± 10.9 mm Hg), plasma glucose (from 91.0 ± 5.6 mg/dL to 87.2 ± 5.2 mg/dL), homeostatic model assessment for insulin resistance (from 2.2 ± .9 to 1.0 ± .8), triglycerides (from 88.0 [range, 79.5-103.5] mg/dL to 61.0 [range, 2.0-76.5] mg/dL), alanine aminotransferase, gamma-glutamyl transpeptidase NFS (from -1.0 ± 1.0 to -1.9 ± 1.2), and high-density lipoprotein cholesterol (from 56.9 ± 10.5 mg/dL to 77.9 ± 17.4 mg/dL) at 5 years after surgery. A total of 108 MUMO patients (84.4%) who became metabolically healthy after 1 year stayed healthy at 5 years.

CONCLUSIONS

MBS induced a midterm improvement in cardiometabolic and NAFLD markers in MHMO patients. Seventy-six percent of MUMO patients became metabolically healthy at 5 years after MBS.

Additional Metabolic Effects of Bariatric Surgery in Patients with a Poor Mid-Term Weight Loss Response: A 5-Year Follow-Up Study

To ascertain the 5-year metabolic effects of bariatric surgery in poor weight loss (WL) responders and establish associated factors. Methods: Retrospective analysis of a non-randomised prospective cohort of bariatric surgery patients completing a 5-year follow-up. Mid-term poor WL was considered when 5-year excess weight loss was <50%. Results: Forty-three (20.3%) of the 212 included patients were mid-term poor WL responders. They showed an improvement in all metabolic markers at 2 years, except for total cholesterol. This improvement with respect to baseline was maintained at 5 years for plasma glucose, HbA1c, HOMA, HDL and diastolic blood pressure; however, LDL cholesterol, triglycerides and systolic blood pressure were similar to presurgical values. Comorbidity remission rates were comparable to those obtained in the good WL group except for hypercholesterolaemia (45.8% vs. poor WL, p = 0.005). On multivariate analysis, lower baseline HDL cholesterol levels, advanced age and lower preoperative weight loss were independently associated with poor mid-term WL. Conclusions: Although that 1 in 5 patients presented suboptimal WL 5 years after bariatric surgery, other important metabolic benefits were maintained.

Kidney injury molecule-1: A potential marker of renal recovery after laparoscopic sleeve gastrectomy

Background

Bariatric surgeries were reported to improve diabetes and hypertension; however, the effect on renal recovery has not been fully explored. The aim of this study was to evaluate the effect of laparoscopic sleeve gastrectomy (LSG) in morbidly obese patients on renal function, degree of albuminuria, and kidney injury molecule-1 (KIM-1) level.

Methods

This was a prospective observational study conducted at Mansoura University Hospitals from January to June 2017. Forty-four morbidly obese patients (29 females and 15 males) who met the 1991 WHO criteria for obesity surgery were included. Patients underwent surgical LSG for treatment of morbid obesity, and all were followed for 6 months after surgery. Demographic, clinical, and laboratory data were collected and compared before and after surgery. Primary endpoints were the differences of albuminuria, estimated glomerular filtration rate (eGFR) and serum KIM-1 between baseline (pre-surgery) and 6-month post-surgery values.

Results

Six-month post-surgery data showed significant reduction of body mass index, HbA1c, microalbuminuria, and serum KIM-1, and a significant increase in eGFR (all, P < 0.001). The serum KIM-1 level positively correlated with microalbuminuria and serum creatinine (r = 0.596, P = 0.001 and r = 0.402, P = 0.034, respectively). Postoperative data showed that patients with microalbuminuria had significantly lower eGFR and higher KIM-1 values than those without microalbuminuria (P = 0.003 and 0.049, respectively).

Conclusion

We showed potential benefits of LSG against obesity-associated kidney damage. This is evidenced by improving eGFR and reducing levels of both KIM-1 and microalbuminuria. The serum level of KIM-1 may be a potential marker for renal recovery after LSG.

Remission of Type 2 Diabetes and Sleeve Gastrectomy in Morbid Obesity: a Comparative Systematic Review and Meta-analysis

BACKGROUND

The sleeve gastrectomy (SG) has gained popularity which has resulted in a rising number of patients with T2DM to undergo this procedure. This systematic review and meta-analysis aimed to compare the long-term effects of SG on T2DM remission with remission seen after Roux-en-Y gastric bypass (RYGB) or gastric banding (GB).

METHODS

A literature search was performed in PubMed and Cochrane Library using the following search terms: 'sleeve gastrectomy', 'diabetes', 'gastric bypass' and 'gastric banding'. Studies published between January 2000 and April 2018, and with following inclusion criteria were selected for this review: BMI ≥ 35 kg/m2, age ≥ 18 years, follow-up ≥ 1 year, T2DM. Data was statistically analysed using a random-effects model and results were expressed as odds ratio with 95% confidence interval.

RESULTS

After exclusion, 35 out of an initial 748 studies, consisting of 18 138 T2DM patients, remained for inclusion. Of these patients, 2480 underwent a SG. The remaining patients underwent a RYGB (n = 10,597) or GB (n = 5061). One year postoperatively, SG patients reached significantly (OR 0.71, p = 0.003) less T2DM remission than RYGB. After stratifying for different criteria for remission, RYGB still tended to result in higher remission rates, but the difference was not statistically significant. Beyond 1 year of follow-up, the difference between RYGB and SG in terms of T2DM remission decreased. SG was superior to the GB (OR 2.17, p = 0.001) after 1 year of follow-up.

CONCLUSION

This review demonstrates important remission of T2DM following SG. Nevertheless, as remission was significantly more often observed following RYGB surgery, the latter procedure remains the gold standard for reaching T2DM remission in patients with concurrent obesity.

Metabolically Healthy Obesity and Bariatric Surgery

A peculiar category of persons with obesity lacking common metabolic disturbances has been depicted and termed as metabolically healthy obesity (MHO). Yet, although MHO patients are free of obesity-associated complications, they might not be entirely precluded from developing cardio-metabolic disorders. Among patients with morbid obesity (MO) who are referred to bariatric surgery, a subset of metabolically healthy MO (MHMO) has been identified and the question arises if these patients would benefit from surgery in terms of mitigating the peril of cardio-metabolic complications. We revisited the pathophysiological mechanisms that define MHO, the currently available data on the cardio-metabolic risk of these patients and finally we reviewed the benefits of bariatric surgery and the urge to better characterize MHMO before submission to surgery.

Effect of Laparoscopic Sleeve Gastrectomy on Type 2 Diabetes Mellitus in Patients with Body Mass Index less than 30 kg/m2

BACKGROUND

Laparoscopic sleeve gastrectomy (LSG) has been proved to be the most effective treatment strategy for the treatment of type 2 diabetes mellitus (T2DM) with a body mass index ≥ 30 kg/m² achieving high remission rates. However, there are few clinical studies on the treatment of T2DM patients with a body mass index less than 30 kg/m² by LSG. This study aims to study the effect of LSG on type 2 diabetes mellitus(T2DM) in patients with a body mass index (BMI) less than 30 kg/m².

METHODS

The clinical data of 25 patients with type 2 diabetes mellitus (T2DM) and body mass index 23.23-29.97 kg/m² who were treated by LSG at the Department of Bariatric and Metabolic Surgery in China-Japan Union Hospital of Jilin University from May 2016 to May 2017 were retrospectively analyzed. The changes of fasting plasma glucose, glycosylated hemoglobin, insulin resistance index, body weight, body mass index, waist circumference, blood pressure, heart rate, blood lipids, and uric acid were analyzed at 3 months, 6 months, and 12 months after operation, respectively. All the clinical data were analyzed by SPSS 22.0. They were tested with a single-sample K-S test to determine whether they were normal distribution data. The normal distribution data were analyzed by a matched t test, and the Mann-Whitney test was used to examine skewed data.

RESULTS

All patients (9 males, 16 females) with a median age of 57(24~65) years were treated successfully by laparoscopic sleeve gastrectomy. The median duration of type 2 diabetes mellitus was 10(0~20)years. The preoperative fasting plasma glucose, glycosylated hemoglobin, body weight, body mass index, and waist circumference were 10.32 ± 2.66 mmol/L,8.20 ± 1.47%,76.54 ± 10.02 kg,27.92 ± 1.72 kg/m², and 99.88 ± 5.38 cm, respectively. The meaning fasting plasma glucose was 7.26 ± 1.36 mmol/L, 6.90 ± 1.07 mmol/L, and 6.62 ± 0.97 mmol/L, respectively, at 3, 6, and 12 months after operation. The mean HbAlc in the same observation intervals was 6.88 ± 1.23%,6.54 ± 1.02%, and 6.51 ± 0.89%, respectively. The body weight was 62.18 ± 8.38 kg,59.07 ± 8.58 kg, and 58.62 ± 8.53 kg, respectively. The corresponding body mass index was 22.56 ± 1.56 kg/m², 21.35 ± 1.58 kg/m², and 21.24 ± 1.86 kg/m², respectively. The waist circumference was 82.84 ± 5.10 cm,78.60 ± 5.21 cm, and 76.92 ± 5.21 cm, respectively. The complete remission rates of type 2 diabetes mellitus were 40%, 60%, and 68%, respectively, at 3, 6, and 12 months after operation. The complete remission rates for insulin resistance index were 52.4%, 80%, and 80%, postoperatively, at 3, 6, and 12 months, respectively. The complete remission rates of hypertension were 22.2%, 50%, and 75%,respectively, at 3,6, and 12 months after operation. The complete remission rates of hypertriglyceridemia were 66.7%, 66.7%, and 100%,and the complete remission rates of hypercholesterolemia were 41.7%, 60%, and 100%;the abnormal elevations of plasma cholesterol in two patients with normal cholesterol before operation were significantly higher, postoperatively, at 3 monthsand 6 months, respectively. The complete remission rates of hyperuricemia were 37.5%, 33.3%, and 100% in the same observation period, respectively. The abnormal elevations of uric acid in two patients with normal uricemia before operation were significantly higher at postoperative 3 months.

CONCLUSION

LSG has a significant effect on patients with type 2 diabetes mellitus whose BMI less than 30 kg/m² in a short time, but its long-term effectiveness needs to be further followed up.

The influence of bariatric surgery on serum levels of irisin and nesfatin-1

Introduction: Bariatric surgery is associated with multiple endocrine and metabolic changes. Irisin and nesfatin-1 have recently been described as regulatory peptides involved in obesity-related insulin resistance. Our aim was to analyze the changes of those two molecules observed in patients after bariatric procedures. Materials and methods: This prospective study involved 40 patients treated for morbid obesity. Irisin and nesfatin-1 were measured before, 6 months and 1 year after surgical intervention. We also gathered demographic data, information concerning comorbidities, factors related to the surgery and outcomes of bariatric treatment. Results: Twenty-seven patients completed the study (15 females). The mean age of the group was 43.5 ± 10.4 years. Six (22.2%) patients were submitted to Laparoscopic Sleeve Gastrectomy and 21 (77.8%) patients were submitted to Laparoscopic Roux-en-Y Gastric Bypass. The participants in our study achieved significant weight loss. The irisin level remained stable in the whole study group during all three measurements included in our study protocol (p = .71). Our study group presented a reduction of the nesfatin-1 level 6 months after bariatric surgery and a slight further decrease after one-year observation, although these changes were also not significant (p = .17). Conclusions: We did not find any significant correlation between changes of irisin or nesfatin-1 level and bariatric surgery, as an aid in the regulation of glucose metabolism.

Reduction of 24-h blood pressure variability in extreme obese patients 10 days and 6 months after bariatric surgery depending on pre-existing hypertension

Bariatric surgery is considered as a first line treatment in extreme obese patients to achieve a reduction in health risks. However, after surgical procedure obese patients with normal blood pressure (BP) levels still present residual risk, which may be partly related to lack of correction of BP profile and variability.

AIM

To evaluate short (10 days) and mid-term (6 months) changes of mean values, profile and variability of BP after bariatric surgery in extremely obese patients with and without hypertension.

MATERIALS & METHODS

A follow-up of cross-sectional study was conducted in 90 obese patients (aged 41.7 ± 11.3, BMI = 46.7 ± 5.7 kg/m2), who met the eligibility criteria and underwent bariatric surgery. Each patient underwent 24-h ambulatory BP monitoring with profile and variability estimation before, 10 days and 6 months after the intervention.

RESULTS

Sixty-seven (74.4%) patients had hypertension. Significant decrease from baseline in mean values of systolic and diastolic BP in 10 days (p < .005) and 6 months (p < .005) follow-up were observed only in patients with hypertension. Moreover, only hypertensive subjects revealed significant reduction (p < 0,05) from baseline in 24-h systolic and diastolic BP weighted standard deviation and average real variability after surgical procedure. No changes were found in dipping status.

CONCLUSIONS

Bariatric surgery not only decreased BP levels, but also contributed to reduction in BP variability in early period after intervention mainly in patients with pre-existing hypertension.

In-and-Out Molecular Changes Linked to the Type 2 Diabetes Remission after Bariatric Surgery: An Influence of Gut Microbes on Mitochondria Metabolism

Different kinds of gastrointestinal tract modulations known as “bariatric surgery” are actually the most effective treatment for obesity and associated co-morbidities, such as type 2 diabetes (T2DM). The potential causes of those effects have yet to be explained. In our study, we focused on molecular changes evoked by laparoscopic sleeve gastrectomy leading to T2DM remission. Two complementary metabolomics techniques, namely, liquid chromatography coupled with mass spectrometry (LC-MS) and gas chromatography mass spectrometry (GC-MS), were used to study those effects in a group of 20 obese patients with T2DM selected from a cohort of 372 obese individuals who underwent bariatric surgery and did not receive anti-diabetic treatment afterward. Modified levels of carnitines, lipids, amino acids (including BCAA) and α- and β-hydroxybutyric acids were detected. Presented alterations suggest a major role of mitochondria activity in T2DM remission process. Moreover, some of the observed metabolites suggest that changes in gut microbiota composition may also correlate with the tempo of diabetes recovery. Additional analyses confirmed a relationship between biochemical and clinical parameters and the aforementioned metabolites, thereby, highlighting a role of mitochondria and microbes. Our data suggests that there is a previously undescribed relationship between mitochondria and gut microbiota, which changes after the bariatric surgery. More investigations are needed to confirm and explore the observed findings.

Diabetes management before, during, and after bariatric and metabolic surgery

Metabolic surgery is unrivaled by other therapeutic modalities due to its ability to foster diabetes remission. Metabolic surgery is an integral therapeutic modality in obese and morbidly obese populations because pharmacological and behavioral therapy often fail to effectively manage type II diabetes. However, given the invasiveness of the metabolic surgery relative to behavioral therapy and the need to conform to preparatory and discharge guidelines, patients must adhere to strict nutritional and diabetes management protocols. Also, the pharmacological regimen that is instituted upon discharge is distinct from the preoperative regimen. Oftentimes, the dose for insulin and oral medications are significantly decreased or withdrawn. As time elapses and depending on several factors (e.g., exercise adherence), diabetes control becomes tenuous in a small portion of the patients because there is weight regain and on-going beta cell failure. At this time interval, intensification of diabetes therapy becomes prudent. Indeed, pharmacotherapy from the preoperative to the postoperative phase is labile and may be complex. Therefore, by discussing pharmacology options during the preoperative, perioperative, and postoperative period, the goal is to guide clinician-driven care.

Comparison of metabolic outcomes in patients undergoing laparoscopic roux-en-Y gastric bypass versus sleeve gastrectomy - a systematic review and meta-analysis of randomised controlled trials

BACKGROUND AND OBJECTIVES

Bariatric surgery is the most effective treatment for morbid obesity and is known to have beneficial effects on glycaemic control in patients with type 2 diabetes mellitus (T2DM) and in diabetes prevention. The preferred type of surgery and mechanism of action is, however, unclear. We performed a systematic review and meta-analysis of randomised controlled trials (RCTs) comparing the effects of laparoscopic roux-en-Y gastric bypass (RYGB) with those of sleeve gastrectomy (SG) on metabolic outcome, with a special focus on glycaemic control.

METHODS

A literature search of the Medline, Pubmed, Cochrane, Embase and SCOPUS databases was performed in November 2014 for RCTs comparing RYGB with SG in overweight and obese patients with or without T2DM. The primary outcome was improvement in postoperative glycaemic control. Secondary outcomes included weight-related and lipid metabolism parameters. Synthesis of these data followed established statistical procedures for meta-analysis.

RESULTS

Sixteen RCTs with a total of 1132 patients with overweight or obesity were included in the analysis. When compared with patients who underwent SG, those who underwent RYGB showed no difference after 12 months in mean fasting blood glucose (mean difference [MD] -6.22 mg/dl, 95% confidence interval [CI] -17.27 to 4.83; p <0.001). However, there was a better outcome with RYGB, with lower mean fasting glucose levels at 24 months (MD -16.92 mg/dl, 95% CI -21.67 to -12.18), 36 months (MD -5.97mg/dl, 95% CI -9.32 to -2.62) and at 52 months (MD -15.20 mg/dl, 95% CI -27.35 to -3.05) mg/dl; p = 0.010) and lower mean glycated haemoglobin (HbA1 at 12 months (MD -0.47%, 95% CI -0.73 to -0.20%; p <0.001) and at 36 months postoperatively compared to SG. Fasting insulin levels and HOMA indices showed no difference at any stage of follow-up. In the subgroup including only diabetic patients HbA1c showed lower levels at 12 months (MD -0.46%, 95% CI-0.73 to -0.20%). No difference was found for the fasting insulin at baseline and after 12 months. Similarly, when compared to SG, patients that underwent RYGB had lower low-density lipoproteins at 12 months. This effect was lost at 36 months. Patients undergoing RYGB also had lower triglycerides at 12 months and at 52 months, lower cholesterol at 60 months and an improvement of BMI at 52 months postoperatively. BMI values at 12 months and low-density lipoprotein levels at 12 and 36 months were lower for diabetic patients only, as in the overall analysis.

CONCLUSION

Based on this meta-analysis, RYGB is more effective than SG in improving weight loss and short- and mid-term glycaemic and lipid metabolism control in patients with and without T2DM. Therefore, unless contraindicated, RYGB should be the first choice to treat patients with obesity and T2DM and/or dyslipidaemia.

The Role of GLP-1 in the Metabolic Success of Bariatric Surgery

Two of the most popular bariatric procedures, vertical sleeve gastrectomy (VSG) and Roux-en-Y gastric bypass (RYGB), are commonly considered metabolic surgeries because they are thought to affect metabolism in a weight loss-independent manner. In support of this classification, improvements in glucose homeostasis, insulin sensitivity, and even discontinuation of type 2 diabetes mellitus (T2DM) medication can occur before substantial postoperative weight loss. The mechanisms that underlie this effect are unknown. However, one of the common findings after VSG and RYGB in both animal models and humans is the sharp postprandial rise in several gut peptides, including the incretin and satiety peptide glucagonlike peptide-1 (GLP-1). The increase in endogenous GLP-1 signaling has been considered a primary pathway leading to postsurgical weight loss and improvements in glucose metabolism. However, the degree to which GLP-1 and other gut peptides are responsible for the metabolic successes after bariatric surgery is continually debated. In this review we discuss the mechanisms underlying the increase in GLP-1 and its potential role in the metabolic improvements after bariatric surgery, including remission of T2DM. Understanding the role of changes in gut peptides, or lack thereof, will be crucial in understanding the critical factors necessary for the metabolic success of bariatric surgery.

Effect of Bariatric Surgery-Induced Weight Loss on Platelet Count and Mean Platelet Volume: a 12-Month Follow-Up Study

BACKGROUND

Abdominal obesity is strongly correlated with cardiovascular risk and associated with platelet hyperactivity. This hyperactivity is associated with an increase in mean platelet volume (MPV). Few data are available about changes in platelet counts and MPV in obese patients after bariatric surgery (BS). The purpose of this study was to describe quantitative and qualitative changes in the platelet lineage after BS.

METHODS

One hundred twenty-eight consecutive patients were included. The mean age was 43 ± 12 years, 77 % of patients were female, and the mean preoperative BMI was 44 ± 6 kg/m². Ninety patients (71 %) had a Roux-en-Y gastric bypass (RYGBP), and 38 (29 %) had a sleeve gastrectomy (SG). Patients were evaluated preoperatively, and postoperative follow-up was performed at 3, 6, and 12 months. The postoperative evaluation included blood samples for full blood count (FBC), including measure of mean platelet volume (MPV).

RESULTS

At the 12-month follow-up, the reduction in preoperative weight was 29 ± 9 %. We showed a significant decrease in platelet count (245 ± 62 vs. 234 ± 54 G/L; p = 0.0015) found in parallel with a non-significant decrease in MPV (9.27 ± 1.1 vs. 9.22 ± 1.05; p = 0.34). With regard to the intervention type, SG caused a more significant decrease in platelet count than RYGBP (p = 0.02). There was no significant difference in MPV variations between the two groups (p = 0.08).

CONCLUSIONS

Our results suggest that BS has a positive impact on platelet metabolism, possibly mediated by weight loss. These data need to be confirmed to understand the multifactorial benefits of BS on cardiovascular risk in obese patients.

Primary experience of bariatric surgery in a newly established private obesity center

Objectives:

To assess the outcomes of different types of bariatric surgeries in a single newly established private obesity center.

Methods:

Retrospectively, we included patients who were entered in the registry for bariatric surgeries in the Obesity Unit, Riyadh National Hospital, Riyadh, Saudi Arabia between January 2013 and September 2014, and completed one year of follow up. Baseline characteristics, percent excess weight loss, and safety data were collected and analyzed.

Results:

A total of 79 patients were included. Based on the type of surgery, patients were divided into 3 groups: laparoscopic Roux-en-Y gastric bypass (RYGB), laparoscopic minigastric bypass (MGBP), and laparoscopic vertical sleeve gastrectomy (SG). After one year, RYGB and MGB patients lost more weight than SG patients. No mortality, or leak were reported and one patient had reoperation after revision laparoscopic RYGB for bleeding. There was one readmission, while 4 patients visited the emergency room for vomiting and dehydration (2 patients), anemia (one patient), and port site infection (one patient).

Conclusion:

Bariatric surgeries are safe when carried out by an experienced bariatric surgeon in the private sector. The outcome of this series is similar to the published results from large international obesity databases.

Using the hyperinsulinemic euglycemic clamp to assess insulin sensitivity at 3 months following Roux-en-Y gastric bypass surgery in type 2 diabetes patients with BMI <35 kg/m2 in China

BACKGROUND

The aim of this study was to describe short-time effect of Roux-en-Y gastric bypass (RYGB) on insulin sensitivity (IS) of Chinese diabetes patients with body mass index (BMI) <35 kg/m² by hyperinsulinemic euglycemic clamp.

MATERIALS AND METHODS

We studied 15 type 2 diabete mellitus (T2DM) patients with BMI <35 kg/m², who underwent laparoscopical Roux-en-Y gastric bypass (LRYGB). Hyperinsulinemic-euglycemic clamp were performed at baseline and at 3 months after LRYGB.

RESULTS

The glucose disposal rate (M value) increased significantly at 3 months after RYGB (from 3.36 ± 1.26 mg kg^-1 min^-1 to 6.30 ± 1.3 mg kg^-1 min^-1, p < 0.001). The time to reach euglycemia at the hyperinsulinemic euglycemic clamp reduced remarkably from baseline to 3 months after RYGB (from 114.40 ± 6.11 min to 97.93 ± 8.57 min, p < 0.001). There was a marked reduction in value of HOMA-IR (from 4.47 ± 2.20 mg kg^-1 min^-1 to 2.10 ± 0.75 mg kg^-1 min^-1, p < 0.001). The parameters of body fat distribution (body weight, BMI, waist circumference, waist to hip radio) changed obviously after surgery. RYGB caused a significant improvement in fasting and postprandial plasma glucose and insulin, HbAc1. Preoperative M value and the time to reach steady-state correlated with changes of M and the time to reach steady-state at 3 months after RYGB.

CONCLUSION

Peripheral and hepatic IS improved remarkably at 3 months following RYGB, as an important mechanism for early improvement in T2DM patients with low BMI. And the time to reach euglycemia at the hyperinsulinemic euglycemic clamp may be an useful index of assessing insulin sensitivity. It is more reasonal to combine the time to reach euglycemia with M value for assessing IS.

Changes of insulin sensitivity and secretion after bariatric/metabolic surgery

Type 2 diabetes (T2D) is classically characterized by failure of pancreatic β-cell function and insulin secretion to compensate for a prevailing level of insulin resistance, typically associated with visceral obesity. Although this is usually a chronic, progressive disease in which delay of end-organ complications is the primary therapeutic goal for medical and behavioral approaches, several types of bariatric surgery, especially those that include intestinal bypass components, exert powerful antidiabetes effects to yield remission of T2D in most cases. It has become increasingly clear that in addition to the known benefits of acute caloric restriction and chronic weight loss to ameliorate T2D, bariatric/metabolic operations also engage a variety of weight-independent mechanisms to improve glucose homeostasis, enhancing insulin sensitivity and secretion to varying degrees depending on the specific operation. In this paper, we review the effects of Roux-en-Y gastric bypass, biliopancreatic diversion, and vertical sleeve gastrectomy on the primary determinants of glucose homeostasis: insulin sensitivity, insulin secretion, and, to the lesser extent that it is known, insulin-independent glucose disposal. A full understanding of these effects should help optimize surgical and device-based designs to provide maximal antidiabetes impact, and it holds the promise to identify targets for possible novel diabetes pharmacotherapeutics. These insights also contribute to the conceptual rationale for use of bariatric operations as "metabolic surgery," employed primarily to treat T2D, including among patients not obese enough to qualify for surgery based on traditional criteria related to high body mass index.

Cost-Effectiveness of Bariatric Surgery for Type 2 Diabetes Mellitus: A Randomized Controlled Trial in China

To compare the remission of type 2 diabetes mellitus (T2DM) through treatment with laparoscopic sleeve gastrectomy (LSG) or laparoscopic Roux-en-Y gastric bypass (LRYGB), and to analyze the cost-effectiveness of medical treatment, LSG, and LRYGB in T2DM patients (BMI ≥ 28).A 2-group randomized controlled trial was conducted at Diabetes Surgery Centre, Beijing Shijitan Hospital in Beijing, China. Subjects were 80 patients ages 16 to 65 years with a body mass index of 28 kg/m or more and duration of T2DM no more than 15 years. Subjects were randomly assigned (1:1) to undergo either LSG (n = 40) or LRYGB (n = 40) between February 3, 2011 and October 31, 2013. Of those patients, 72 (90%) were available at follow-up at 2 years. These patients included 34 (85%) who underwent LSG and 38 (95%) who underwent LRYGB. This study presents the follow-up data at 2 years, which compared LSG and LRYGB in T2DM patients. Partial remission and complete remission were determined, and weight loss, BMI, changes in abdominal circumference, cholesterol, and triglycerides were measured. The cost-effectiveness of each type of bariatric surgery was analyzed with a Markov simulation model that yielded quality-adjusted life-years (QALYs) and costs.From our analysis results, LSG and LRYGB are both have taken a great effect on the reduction of fasting plasma glucose (FPG), hemoglobin A1c (HbA1c), and bodyweight in patients with T2DM. The cost-effectiveness ratios of medical treatment, LSG, and LRYGB respectively are 1589.02, 1028.97, and 1197.44 dollars per QALY.Our analysis indicates that LSG appear to provide a cost-effective method of T2DM treatment for the patients.

Laparoscopic sleeve gastrectomy: More than a restrictive bariatric surgery procedure?

Sleeve gastrectomy (SG) is a restrictive bariatric surgery technique that was first used as part of restrictive horizontal gastrectomy in the original Scopinaro type biliopancreatic diversion. Its good results as a single technique have led to a rise in its use, and it is currently the second most performed technique worldwide. SG achieves clearly better results than other restrictive techniques and is comparable in some aspects to the Roux-en-Y gastric bypass, the current gold standard in bariatric surgery. These benefits have been associated with different pathophysiologic mechanisms unrelated to weight loss such as increased gastric emptying and intestinal transit, and activation of hormonal mechanisms such as increased GLP-1 hormone and decreased ghrelin. The aim of this review was to highlight the salient aspects of SG regarding its historical evolution, pathophysiologic mechanisms, main results, clinical applications and perioperative complications.

A meta-analysis of 2-year effect after surgery: laparoscopic Roux-en-Y gastric bypass versus laparoscopic sleeve gastrectomy for morbid obesity and diabetes mellitus

Literature search was performed for bariatric surgery from inception to September 2013, in which the effects of laparoscopic Roux-en-Y gastric bypass (LRYGB) and laparoscopic sleeve gastrectomy (LSG) on body mass index (BMI), percentage of excess weight loss (EWL%), and diabetes mellitus (DM) were compared 2 years post-surgery. A total of 9,756 cases of bariatric surgery from 16 studies were analyzed. Patients receiving LRYGB had significantly lower BMI and higher EWL% compared with those receiving LSG (BMI mean difference (MD) = -1.38, 95% confidence interval (CI) = -1.72 to -1.03; EWL% MD = 5.06, 95% CI = 0.24 to 9.89). Improvement rate of DM was of no difference between the two types of bariatric surgeries (RR = 1.05, 95% CI = 0.90 to 1.23). LRYGB had better long-term effect on body weight, while both LRYGB and LSG showed similar effects on DM.

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.

Vitamin D concentrations in familial combined hyperlipidemia: effects of lipid lowering treatment

BACKGROUND

Vitamin D deficiency has been linked to several cardiovascular risk factors but information regarding vitamin D concentrations in familial combined hyperlipidemia (FCHL) is lacking. Our objective was to examine vitamin D concentrations in patients with FCHL and to study the effects of lipid-lowering therapy.

METHODS

We conducted a cross sectional study on 59 patients with FCHL and 48 healthy controls. We analyzed 25-hydroxyvitamin D (25(OH)D) concentrations and their association with lipid parameters, anthropometric measures, C-reactive protein and homeostasis model assessment (HOMA) index. Twenty-three patients with FCHL were also included in a longitudinal study conducted to analyze 25-hydroxyvitamin D concentrations before and after treatment for dyslipidemia.

RESULTS

After adjustment for body mass index and seasonality, patients with FCHL had lower vitamin D concentrations than controls. Adjusted means (standard error of the mean (S.E.M)) for 25(OH)D according to the presence or absence of FCHL were 62.8 (3.6) nmol/L for patients with FCHL and 74.8 (4.1) nmol/L for controls (p = 0.021). In FCHL, hypovitaminosis D was associated with features of atherogenic dyslipidemia. After lipid-lowering therapy, vitamin D concentrations increased (51.0 ± 31.3 to 58.9 ± 24.6 nmol/L (P = 0.022)). However, changes in 25(OH)D concentrations did not correlate with changes in other parameters.

CONCLUSIONS

Our findings suggest that FCHL is associated with decreased vitamin D concentrations and that treatment for dyslipidemia improves vitamin D status through an unknown mechanism. Further studies are needed to replicate these data in larger populations and to elucidate the mechanisms involved in this association.

Diabetes remission and glycemic response to pre-bariatric surgery diet

BACKGROUND

Before bariatric surgery, some patients with type 2 diabetes mellitus (T2DM) experience improvement in blood glucose control and reduced insulin requirements while on a preoperative low-calorie diet (LCD). We hypothesized that patients who exhibit a significant glycemic response to this diet are more likely to experience remission of their diabetes in the postoperative period.

MATERIALS AND METHODS

Insulin-dependent T2DM patients undergoing bariatric surgery between August 2006 and February 2011 were eligible for inclusion. Insulin requirements at day 0 and 10 of the LCD were compared. Patients with a ≥ 50% reduction in total insulin dosage to maintain appropriate blood glucose control were considered rapid responders to the preoperative LCD. All others were non-rapid responders. We analyzed T2DM remission rates up to 1 y postoperatively.

RESULTS

A total of 51 patients met inclusion criteria and 29 were categorized as rapid responders (57%). The remaining 22 were considered non-rapid responders (43%). The two groups did not differ demographically. Rapid responders had greater T2DM remission rates at 6 (44% versus 13.6%; P = 0.02) and 12 mo (72.7% versus 5.9%; P < 0.01). In patients undergoing laparoscopic gastric bypass, rapid responders showed greater excess weight loss at 3 mo (40.1% versus 28.2%; P < 0.01), 6 mo (55.2% versus 40.2%; P < 0.01), and 12 mo (67.7% versus 47.3%; P < 0.01).

CONCLUSIONS

Insulin-dependent T2DM bariatric surgery patients who display a rapid glycemic response to the preoperative LCD are more likely to experience early remission of T2DM postoperatively and greater weight loss.