Gastric bypass surgery vs intensive lifestyle and medical intervention for type 2 diabetes: the CROSSROADS randomised controlled trial

Mechanisms Underlying Type 2 Diabetes Remission After Metabolic Surgery

Type 2 diabetes prevalence is increasing dramatically worldwide. Metabolic surgery is the most effective treatment for selected patients with diabetes and/or obesity. When compared to intensive medical therapy and lifestyle intervention, metabolic surgery has shown superiority in achieving glycemic improvement, reducing number of medications and cardiovascular risk factors, which translates in long-term benefits on cardiovascular morbidity and mortality. The mechanisms underlying diabetes improvement after metabolic surgery have not yet been clearly understood but englobe a complex interaction among improvements in beta cell function and insulin secretion, insulin sensitivity, intestinal gluconeogenesis, changes in glucose utilization, and absorption by the gut and changes in the secretory pattern and morphology of adipose tissue. These are achieved through different mediators which include an enhancement in gut hormones release, especially, glucagon-like peptide 1, changes in bile acids circulation, gut microbiome, and glucose transporters expression. Therefore, this review aims to provide a comprehensive appraisal of what is known so far to better understand the mechanisms through which metabolic surgery improves glycemic control facilitating future research in the field.

Prediction of Type 2 Diabetes Remission after Bariatric or Metabolic Surgery

Bariatric surgery has evolved from a surgical measure for treating morbid obesity to an epochal remedy for treating metabolic syndrome as a whole, which is represented by type 2 diabetes mellitus. Numerous clinical trials have advocated bariatric or metabolic surgery over nonsurgical interventions because of markedly superior metabolic outcomes in morbidly obese patients who satisfy traditional criteria for bariatric surgery (body mass index [BMI] >35 kg/m2) and in less obese or simply overweight patients. Nevertheless, not all diabetes patients achieve the most desirable outcomes; i.e., diabetes remission after metabolic surgery. Thus, candidates for metabolic surgery should be carefully selected based on comprehensive preoperative assessments of the risk-benefit ratio. Predictors for diabetes remission after metabolic surgery may be classified into two groups based on mechanism of action. The first is indices for preserved pancreatic beta-cell function, including younger age, shorter duration of diabetes, and higher C-peptide level. The second is the potential for an insulin resistance reduction, including higher baseline BMI and visceral fat area. Several prediction models for diabetes remission have been suggested by merging these two to guide the joint decision-making process between clinicians and patients. Three such models, DiaRem, ABCD, and individualized metabolic surgery scores, provide an intuitive scoring system and have been validated in an independent external cohort and can be utilized in routine clinical practice. These prediction models need further validation in various ethnicities to ensure universal applicability.

Network meta-analysis of the relative efficacy of bariatric surgeries for diabetes remission

BACKGROUND

Bariatric surgery leads to a higher remission rate for type 2 diabetes mellitus than non-surgical treatment. However, it remains unsolved which surgical procedure is the most efficacious. This network meta-analysis aimed to rank surgical procedures in terms of diabetes remission.

METHODS AND FINDINGS

We electronically searched for randomized controlled trials in which at least one surgical treatment was included among multiple arms and the diabetes remission rate was included in study outcomes. A random-effects network meta-analysis was performed within a frequentist framework. The hierarchy of treatments was expressed as the surface under the cumulative ranking curve value. Results of the analysis of 25 eligible randomized controlled trials that covered non-surgical treatments and eight surgical procedures (biliopancreatic diversion [BPD], BPD with duodenal switch, Roux-en Y gastric bypass, mini gastric bypass [mini-GBP], laparoscopic adjustable gastric banding, laparoscopic sleeve gastrectomy, greater curvature plication and duodenal-jejunal bypass) showed that BPD and mini-GBP had the highest surface under the cumulative ranking curve values among the eight surgical treatments.

CONCLUSION

Current network meta-analysis indicated that BPD or mini-GBP achieved higher diabetes remission rates than the other procedures. However, the result needs to be interpreted with caution considering that these procedures were in the minority of bariatric surgeries.

Bariatric surgery, lifestyle interventions and orlistat for severe obesity: the REBALANCE mixed-methods systematic review and economic evaluation

BACKGROUND

Adults with severe obesity [body mass index (BMI) of ≥ 35 kg/m2] have an increased risk of comorbidities and psychological, social and economic consequences.

OBJECTIVES

Systematically review bariatric surgery, weight-management programmes (WMPs) and orlistat pharmacotherapy for adults with severe obesity, and evaluate the feasibility, acceptability, clinical effectiveness and cost-effectiveness of treatment.

DATA SOURCES

Electronic databases including MEDLINE, EMBASE, PsycINFO, the Cochrane Central Register of Controlled Trials and the NHS Economic Evaluation Database were searched (last searched in May 2017).

REVIEW METHODS

Four systematic reviews evaluated clinical effectiveness, cost-effectiveness and qualitative evidence for adults with a BMI of ≥ 35 kg/m2. Data from meta-analyses populated a microsimulation model predicting costs, outcomes and cost-effectiveness of Roux-en-Y gastric bypass (RYGB) surgery and the most effective lifestyle WMPs over a 30-year time horizon from a NHS perspective, compared with current UK population obesity trends. Interventions were cost-effective if the additional cost of achieving a quality-adjusted life-year is < £20,000-30,000.

RESULTS

A total of 131 randomised controlled trials (RCTs), 26 UK studies, 33 qualitative studies and 46 cost-effectiveness studies were included. From RCTs, RYGB produced the greatest long-term weight change [-20.23 kg, 95% confidence interval (CI) -23.75 to -16.71 kg, at 60 months]. WMPs with very low-calorie diets (VLCDs) produced the greatest weight loss at 12 months compared with no WMPs. Adding a VLCD to a WMP gave an additional mean weight change of -4.41 kg (95% CI -5.93 to -2.88 kg) at 12 months. The intensive Look AHEAD WMP produced mean long-term weight loss of 6% in people with type 2 diabetes mellitus (at a median of 9.6 years). The microsimulation model found that WMPs were generally cost-effective compared with population obesity trends. Long-term WMP weight regain was very uncertain, apart from Look AHEAD. The addition of a VLCD to a WMP was not cost-effective compared with a WMP alone. RYGB was cost-effective compared with no surgery and WMPs, but the model did not replicate long-term cost savings found in previous studies. Qualitative data suggested that participants could be attracted to take part in WMPs through endorsement by their health-care provider or through perceiving innovative activities, with WMPs being delivered to groups. Features improving long-term weight loss included having group support, additional behavioural support, a physical activity programme to attend, a prescribed calorie diet or a calorie deficit.

LIMITATIONS

Reviewed studies often lacked generalisability to UK settings in terms of participants and resources for implementation, and usually lacked long-term follow-up (particularly for complications for surgery), leading to unrealistic weight regain assumptions. The views of potential and actual users of services were rarely reported to contribute to service design. This study may have failed to identify unpublished UK evaluations. Dual, blinded numerical data extraction was not undertaken.

CONCLUSIONS

Roux-en-Y gastric bypass was costly to deliver, but it was the most cost-effective intervention. Adding a VLCD to a WMP was not cost-effective compared with a WMP alone. Most WMPs were cost-effective compared with current population obesity trends.

FUTURE WORK

Improved reporting of WMPs is needed to allow replication, translation and further research. Qualitative research is needed with adults who are potential users of, or who fail to engage with or drop out from, WMPs. RCTs and economic evaluations in UK settings (e.g. Tier 3, commercial programmes or primary care) should evaluate VLCDs with long-term follow-up (≥ 5 years). Decision models should incorporate relevant costs, disease states and evidence-based weight regain assumptions.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42016040190.

FUNDING

The National Institute for Health Research Health Technology Assessment programme. The Health Services Research Unit and Health Economics Research Unit are core funded by the Chief Scientist Office of the Scottish Government Health and Social Care Directorate.

Association Between Bariatric Surgery and Macrovascular Disease Outcomes in Patients With Type 2 Diabetes and Severe Obesity

IMPORTANCE

Macrovascular disease is a leading cause of morbidity and mortality for patients with type 2 diabetes, and medical management, including lifestyle changes, may not be successful at lowering risk.

OBJECTIVE

To investigate the relationship between bariatric surgery and incident macrovascular (coronary artery disease and cerebrovascular diseases) events in patients with severe obesity and type 2 diabetes.

DESIGN, SETTING, AND PARTICIPANTS

In this retrospective, matched cohort study, patients with severe obesity (body mass index ≥35) aged 19 to 79 years with diabetes who underwent bariatric surgery from 2005 to 2011 in 4 integrated health systems in the United States (n = 5301) were matched to 14 934 control patients on site, age, sex, body mass index, hemoglobin A1c, insulin use, observed diabetes duration, and prior health care utilization, with follow-up through September 2015.

EXPOSURES

Bariatric procedures (76% Roux-en-Y gastric bypass, 17% sleeve gastrectomy, and 7% adjustable gastric banding) were compared with usual care for diabetes.

MAIN OUTCOMES AND MEASURES

Multivariable-adjusted Cox regression analysis investigated time to incident macrovascular disease (defined as first occurrence of coronary artery disease [acute myocardial infarction, unstable angina, percutaneous coronary intervention, or coronary artery bypass grafting] or cerebrovascular events [ischemic stroke, hemorrhagic stroke, carotid stenting, or carotid endarterectomy]). Secondary outcomes included coronary artery disease and cerebrovascular outcomes separately.

RESULTS

Among a combined 20 235 surgical and nonsurgical patients, the mean (SD) age was 50 (10) years; 76% of the surgical and 75% of the nonsurgical patients were female; and the baseline mean (SD) body mass index was 44.7 (6.9) and 43.8 (6.7) in the surgical and nonsurgical groups, respectively. At the end of the study period, there were 106 macrovascular events in surgical patients (including 37 cerebrovascular and 78 coronary artery events over a median of 4.7 years; interquartile range, 3.2-6.2 years) and 596 events in the matched control patients (including 227 cerebrovascular and 398 coronary artery events over a median of 4.6 years; interquartile range, 3.1-6.1 years). Bariatric surgery was associated with a lower composite incidence of macrovascular events at 5 years (2.1% in the surgical group vs 4.3% in the nonsurgical group; hazard ratio, 0.60 [95% CI, 0.42-0.86]), as well as a lower incidence of coronary artery disease (1.6% in the surgical group vs 2.8% in the nonsurgical group; hazard ratio, 0.64 [95% CI, 0.42-0.99]). The incidence of cerebrovascular disease was not significantly different between groups at 5 years (0.7% in the surgical group vs 1.7% in the nonsurgical group; hazard ratio, 0.69 [95% CI, 0.38-1.25]).

CONCLUSIONS AND RELEVANCE

In this observational study of patients with type 2 diabetes and severe obesity who underwent surgery, compared with those who did not undergo surgery, bariatric surgery was associated with a lower risk of macrovascular outcomes. The findings require confirmation in randomized clinical trials. Health care professionals should engage patients with severe obesity and type 2 diabetes in a shared decision making conversation about the potential role of bariatric surgery in the prevention of macrovascular events.

Obesity and type 2 diabetes: Also linked in therapeutic options

The prevalence of obesity has increased worldwide over the past decades. Obesity is associated with multiple comorbidities, such as type 2 diabetes, that generates a great impact on health and economy. Weight loss in these patients leads to glycemic control so it is a target to achieve. Lifestyle changes are not effective enough and recently other treatments have been developed such as bariatric/metabolic surgery, as well as drugs for type 2 diabetes and antiobesity drugs. The aim of this review is to compare the results in weight reduction and glycemic control of the different kinds of drugs with bariatric / metabolic surgery's results in type 2 diabetes.

Long-term Relapse of Type 2 Diabetes After Roux-en-Y Gastric Bypass: Prediction and Clinical Relevance

OBJECTIVE

Roux-en-Y gastric bypass (RYGB) induces type 2 diabetes remission (DR) in 60% of patients at 1 year, yet long-term relapse occurs in half of these patients. Scoring methods to predict DR outcomes 1 year after surgery that include only baseline parameters cannot accurately predict 5-year DR (5y-DR). We aimed to develop a new score to better predict 5y-DR.

RESEARCH DESIGN AND METHODS

We retrospectively included 175 RYGB patients with type 2 diabetes with 5-year follow-up. Using machine learning algorithms, we developed a scoring method, 5-year Advanced-Diabetes Remission (5y-Ad-DiaRem), predicting longer-term DR postsurgery by integrating medical history, bioclinical data, and antidiabetic treatments. The scoring method was based on odds ratios and variables significantly different between groups. This score was further validated in three independent RYGB cohorts from three European countries.

RESULTS

Compared with 5y-DR patients, patients who had relapsed after 5 years exhibited more severe type 2 diabetes at baseline, lost significantly less weight during the 1st year after RYGB, and regained more weight afterward. The 5y-Ad-DiaRem includes baseline (diabetes duration, number of antidiabetic treatments, and HbA_1c) and 1-year follow-up parameters (glycemia, number of antidiabetic treatments, remission status, 1st-year weight loss). The 5y-Ad-DiaRem was accurate (area under the receiver operating characteristic curve [AUROC], 90%; accuracy, 85%) at predicting 5y-DR, performed better than the Diabetes Remission score (DiaRem) and the Advanced-DiaRem (AUROC, 81% and 84%; accuracy, 79% and 78%, respectively), and correctly reclassified 13 of 39 patients misclassified with the DiaRem. The 5y-Ad-DiaRem robustness was confirmed in the independent cohorts.

CONCLUSIONS

The 5y-Ad-DiaRem accurately predicts 5y-DR and appears relevant to identify patients at risk for relapse. Using this score could help personalize patient care after the 1st year post-RYGB to maximize weight loss, limit weight regains, and prevent relapse.

Ileal interposition coupled with duodenal diverted sleeve gastrectomy versus standard medical treatment in type 2 diabetes mellitus obese patients: long-term results of a case-control study

BACKGROUND

Randomized controlled trials have demonstrated that bariatric surgery is effective in obtaining remission of type 2 diabetes mellitus (T2DM) in obese patients, yet no data exist in the literature from prospective studies with ileal interposition with duodenal diversion sleeve gastrectomy (II-DD-SG). The aim of this case-control study is to investigate if II-DD-SG is superior to medical treatment in T2DM obese patients.

METHODS

Thirty obese patients (BMI > 30) affected by T2DM were recruited for surgery (II-DD-SG) between 2008 and 2011 and were matched with an equal control group which received standard medical treatment. Anthropometric measures, glucose metabolism, cardiovascular risk factors were determined baseline and during follow-up. The primary end point was T2DM remission; reduction of body weight, BMI, and cardiovascular risk factors were secondary end-points.

RESULTS

Shortly after II-DD-SG, normalization of glucose plasma levels and glycated hemoglobin was observed followed by a significant decrease in body weight and BMI. At one-year follow-up, insulin resistance strongly declined as did insulin plasma levels. Complete remission was observed in 26 patients (86%); 2 (6.6%) had partial remission, and two (6.6%) were still diabetic. After 5 years, 17 of 25 patients on follow-up (68%) showed complete remission of T2DM and 56% had remission of cardiovascular risk factors. Only two patients receiving medical treatment showed complete remission of T2DM (p < 0.0001 versus II-DD-SG). No significant changes of anthropometric parameters and lipid metabolism were recorded.

CONCLUSIONS

II-DD-SG is an effective surgical procedure, able to induce complete and prolonged remission of T2DM in obese patients as opposed to medical treatment.

Microvascular Outcomes in Patients With Diabetes After Bariatric Surgery Versus Usual Care: A Matched Cohort Study

Background

Bariatric surgery improves glycemic control in patients with type 2 diabetes mellitus (T2DM), but less is known about microvascular outcomes.

Objective

To investigate the relationship between bariatric surgery and incident microvascular complications of T2DM.

Design

Retrospective matched cohort study from 2005 to 2011 with follow-up through September 2015.

Setting

4 integrated health systems in the United States.

Participants

Patients aged 19 to 79 years with T2DM who had bariatric surgery (n = 4024) were matched on age, sex, body mass index, hemoglobin A1c level, insulin use, diabetes duration, and intensity of health care use up to 3 nonsurgical participants (n = 11 059).

Intervention

Bariatric procedures (76% gastric bypass, 17% sleeve gastrectomy, and 7% adjustable gastric banding) compared with usual care.

Measurements

Adjusted Cox regression analysis investigated time to incident microvascular disease, defined as first occurrence of diabetic retinopathy, neuropathy, or nephropathy.

Results

Median follow-up was 4.3 years for both surgical and nonsurgical patients. Bariatric surgery was associated with significantly lower risk for incident microvascular disease at 5 years (16.9% for surgical vs. 34.7% for nonsurgical patients; adjusted hazard ratio [HR], 0.41 [95% CI, 0.34 to 0.48]). Bariatric surgery was associated with lower cumulative incidence at 5 years of diabetic neuropathy (7.2% for surgical vs. 21.4% for nonsurgical patients; HR, 0.37 [CI, 0.30 to 0.47]), nephropathy (4.9% for surgical vs. 10.0% for nonsurgical patients; HR, 0.41 [CI, 0.29 to 0.58]), and retinopathy (7.2% for surgical vs. 11.2% for nonsurgical patients; HR, 0.55 [CI, 0.42 to 0.73]).

Limitation

Electronic health record databases could misclassify microvascular disease status for some patients.

Conclusion

In this large, multicenter study of adults with T2DM, bariatric surgery was associated with lower overall incidence of microvascular disease (including lower risk for neuropathy, nephropathy, and retinopathy) than usual care.

Primary Funding Source

National Institute of Diabetes and Digestive and Kidney Diseases.

Impact of bariatric surgery on cardiovascular and renal complications of diabetes: a focus on clinical outcomes and putative mechanisms

INTRODUCTION

Cardiovascular and renal disease accounts for a substantial proportion of the morbidity and mortality associated with obesity and type 2 diabetes mellitus (T2DM). Bariatric surgery is associated with improved long-term cardiovascular and renal outcomes.

AREAS COVERED

All major case-control, cohort, and randomized controlled trial studies of bariatric surgery in adults with T2DM were screened and data on prespecified cardiovascular and renal outcomes collated. Bariatric surgery reduces all-cause mortality and risk of cardiovascular disease, albuminuria and progressive chronic kidney disease. Patients with poorer glycemic control and established microvascular disease preoperatively may stand to benefit the most from the surgical approach. Reduced sympathetic drive, remission of glomerular hypertension, enhanced natriuresis, gut microbiota shifts, reduced systemic and renal inflammation, improved lipoprotein profiles, and reductions in chronic cardiac remodeling may all be implicated.

EXPERT COMMENTARY

Ongoing RCTs of bariatric surgery selectively recruiting patients with class 1 obesity and established microvascular complications of diabetes will help to better characterize which subgroups of patients benefit most from this effective therapy.

MANAGEMENT OF ENDOCRINE DISEASE: Which metabolic procedure? Comparing outcomes in sleeve gastrectomy and Roux-en Y gastric bypass

Obesity and its associated comorbidities have become one of the largest challenges for health care in the near future. Conservative therapy for obesity and related comorbidities has a very high failure rate and poor long-term results. Similarly, the conservative and medical management of the majority of metabolic diseases such as type 2 diabetes mellitus are only able to slow down disease progression but have no causal effect on the disease process. Obesity surgery has evolved as a highly effective therapy for severe obesity achieving long-lasting weight loss. Furthermore, several studies have demonstrated the beneficial effects of obesity surgery on reduction of overall mortality, reduction of cardiovascular events and superior control of obesity-related diseases such as type 2 diabetes mellitus, dyslipidemia and also the non-alcoholic steatohepatitis compared to medical therapy. Based on these findings, the term 'metabolic surgery' with the focus on treating metabolic diseases independent of body weight has been coined. Of great interest are recent studies that show that even existing complications of metabolic diseases such as diabetic nephropathy or the non-alcoholic steatohepatitis can be reversed by metabolic surgery. Although metabolic surgery has proven to be a safe and effective treatment for obesity, resolution of comorbidities and enhancing quality of life, it is still uncertain and unclear, which surgical procedure is the most effective to achieve these metabolic effects. The aim of this review is to compare the effects of the two currently most widely used metabolic operations, the Roux-en-Y gastric bypass and the sleeve gastrectomy in the treatment of obesity and its related comorbidities.

Surgical treatment of obesity

Obesity prevalence continues to increase worldwide, as do the numerous chronic diseases associated with obesity, including diabetes, non-alcoholic fatty liver disease, dyslipidemia, and hypertension. The prevalence of bariatric surgery also continues to increase and remains the most effective and sustainable treatment for obesity. Over the last several years, numerous prospective and longitudinal studies have demonstrated the benefits of bariatric surgery on weight loss, mortality, and other chronic diseases. Even though the mechanisms underlying many of these beneficial effects remain poorly understood, surgical management of obesity continues to increase given its unmatched efficacy. In this commentary, we discuss recent clinical advancements as well as several areas needed for future research, including indications for bariatric and metabolic surgery, determination of responders and non-responders, metabolic surgery in non-obese individuals, and the evolving role of bariatric surgery in adolescents.

Effects of Weight-Loss Medications on Cardiometabolic Risk Profiles: A Systematic Review and Network Meta-analysis

BACKGROUND & AIMS

We performed a systematic review and network meta-analysis to evaluate the overall and comparative effects of weight-loss medications approved by the Food and Drug Administration for long-term use on cardiometabolic risk profiles of obese adults.

METHODS

We performed a systematic literature review through February 28, 2017 to identify randomized clinical trials of the effects of Food and Drug Administration-approved weight-loss medications (ie, orlistat, lorcaserin, naltrexone-bupropion, phentermine-topiramate, and liraglutide) administered to obese adults for 1 year or more, compared with placebo or another active agent. Outcomes of interest included changes in blood glucose (fasting blood glucose [FBG] and hemoglobin A1c), cholesterol profile (low-density lipoprotein and high-density lipoproteins), blood pressure (BP; systolic/diastolic), and waist circumference (WC). We performed pair-wise and network meta-analyses with outcomes reported as weighted and standardized mean differences. Quality of evidence was rated using GRADE (Grading of Recommendations Assessment, Development and Evaluation).

RESULTS

In a meta-analysis of 28 randomized controlled trials (29,018 participants; median body mass index, 36.1 kg/m²), we associated weight-loss medications with a modest decrease in FBG (weighted mean difference, 4.0 mg/dL; 95% confidence interval, -4.4 to -3.6 mg/dL) and WC (weighted mean difference, reduction of 3.3 cm; 95% confidence interval, -3.5 to -3.1 cm), without clinically meaningful changes in systolic/diastolic BP or cholesterol profile vs placebo (standardized mean difference <0.2); effects varied among drugs. Phentermine-topiramate use was associated with a substantial decrease in WC and a modest decrease in FBG, hemoglobin A1c, and BP, and had minimal effect on cholesterol. Liraglutide use was associated with a substantial decrease in FBG, hemoglobin A1c, and WC, and a minimal effect on BP and cholesterol. Naltrexone-bupropion use was associated with moderate increase in high-density lipoprotein cholesterol, but had a minimal effect on FBG and WC. Orlistat use was associated with a decrease in low-density lipoprotein and high-density lipoprotein cholesterol. No drug improved all cardiometabolic risk factors.

CONCLUSIONS

In a systematic review and network meta-analysis, we found Food and Drug Administration-approved weight-loss medications to have only modest positive effects on cardiometabolic risk profile. Further research is needed to evaluate the long-term cardiometabolic benefits of these medications.

PROSPERO

CRD42016039486.

Clinical and Patient-Centered Outcomes in Obese Patients With Type 2 Diabetes 3 Years After Randomization to Roux-en-Y Gastric Bypass Surgery Versus Intensive Lifestyle Management: The SLIMM-T2D Study

OBJECTIVE

To compare the effect of Roux-en-Y gastric bypass (RYGB) surgery versus intensive medical diabetes and weight management (IMWM) on clinical and patient-reported outcomes in obese patients with type 2 diabetes.

RESEARCH DESIGN AND METHODS

We prospectively randomized 38 obese patients with type 2 diabetes (15 male and 23 female, with mean ± SD weight 104 ± 16 kg, BMI 36.3 ± 3.4 kg/m², age 52 ± 6 years, and HbA_1c 8.5 ± 1.3% [69 ± 14 mmol/mol]) to laparoscopic RYGB (n = 19) or IMWM (n = 19). Changes in weight, HbA_1c, cardiovascular risk factors (UKPDS risk engine), and self-reported health status (the 36-Item Short-Form [SF-36] survey, Impact of Weight on Quality of Life [IWQOL] instrument, and Problem Areas in Diabetes Survey [PAID]) were assessed.

RESULTS

After 3 years, the RYGB group had greater weight loss (mean -24.9 kg [95% CI -29.5, -20.4] vs. -5.2 [-10.3, -0.2]; P < 0.001) and lowering of HbA_1c (-1.79% [-2.38, -1.20] vs. -0.39% [-1.06, 0.28] [-19.6 mmol/mol {95% CI -26.0, -13.1} vs. -4.3 {-11.6, 3.1}]; P < 0.001) compared with the IMWM group. Changes in cardiometabolic risk for coronary heart disease and stroke were all more favorable in RYGB versus IMWM (P < 0.05 to P < 0.01). IWQOL improved more after RYGB (P < 0.001), primarily due to subscales of physical function, self-esteem, and work performance. SF-36 and PAID scores improved in both groups, with no difference between treatments. A structural equation model demonstrated that improvement in overall quality of life was more strongly associated with weight loss than with improved HbA_1c and was manifest by greater improvements in IWQOL than with either SF-36 or PAID.

CONCLUSIONS

Three years after randomization to RYGB versus IMWM, surgery produced greater weight loss, lower HbA_1c, reduced cardiovascular risk, and improvements in obesity-related quality of life in obese patients with type 2 diabetes.

Prediction of type 2 diabetes remission after metabolic surgery: a comparison of the individualized metabolic surgery score and the ABCD score

BACKGROUND

Metabolic surgery has become increasingly accepted for the treatment of type 2 diabetes (T2D). However, there is limited evidence regarding the optimal candidate and surgical procedure. Although a new individualized metabolic surgery (IMS) score was recently proposed for procedure selection, it has yet to be validated.

OBJECTIVE

To validate the IMS score with regard to remission of T2D after metabolic surgery and compare it with the age, body mass index, C-peptide level, and duration of T2D (ABCD) score.

SETTING

Hospital-based bariatric center.

METHODS

A total of 310 T2D patients who underwent gastric bypass and sleeve gastrectomy at an academic center in Taiwan and had a minimum 5-year follow-up (2004-2012) were examined for the predictive power of complete remission using the IMS and the ABCD scoring systems.

RESULTS

At the 5-year follow-up, weight loss was 27.5%, with mean body mass index decreasing from 37.8 to 27.9 kg/m², mean glycated hemoglobin decreased from 8.6% to 6.1%, and prolonged remission of T2D achieved in 224 (72.3%) T2D patients. Remission rates were higher in patients who underwent gastric bypass than in those who underwent sleeve gastrectomy (73.6% versus 66.1%; P = .04), regardless of T2D severity, and were 96%, 68%, and 16% in patients with IMS mild, moderate, and severe scores, respectively. Although both scores predicted the success of surgery, the ABCD was better in patients with IMS moderate scores.

CONCLUSION

Metabolic surgery is an option for T2D patients with obesity. The ABCD score may be better at predicting T2D remission after metabolic surgery compared with the IMS score.

Upregulation of Ghrelin Gene Expression in the Excluded Stomach of Obese Women with Type 2 Diabetes After Roux-en-Y Gastric Bypass in the SURMetaGIT Study

BACKGROUND

Mechanisms of type 2 diabetes remission (T2Dr) after Roux-en-Y gastric bypass (RYGB) in obese patients appear to involve gastrointestinal hormones.

OBJECTIVE

The objective of this study is to explore changes in ghrelin plasma levels and ghrelin gastrointestinal gene expression (GHRL) after RYGB, and their relationships to T2Dr.

SETTING

In 20 obese women with T2D, before and 3 months after RYGB, we assessed GHRL expression by microarray and quantitative RT-PCR in gastrointestinal biopsy samples and plasma levels of ghrelin.

RESULTS

After RYGB, GHRL expression increased in the excluded stomach (p < 0.05) with no change in other gastrointestinal sites. There were no significant changes in ghrelin plasma levels and no correlations with T2Dr.

CONCLUSIONS

After RYGB, over-expression of GHRL gene occurs only in the excluded stomach with no correlation to T2Dr.

β-Cell Failure or β-Cell Abuse?

This review is motivated by the need to question dogma that has not yielded significant improvements in outcomes of Type 2 Diabetes treatment: that insulin resistance is the driver of ß-Cell failure and resulting hyperglycemia. We highlight the fact that hyperlipidemia, insulin resistance, and hyperinsulinemia all precede overt diabetes diagnosis and can each induce the other when tested experimentally. New research highlights the importance of high levels of circulating insulin as both a driver of weight gain and insulin resistance. Data from our lab and others document that several nutrients and environmental toxins can stimulate insulin secretion at non-stimulatory glucose in the absence of insulin resistance. This occurs either by direct action on the ß-Cell or by shifting its sensitivity to known secretagogues. We raise the next logical question of whether ß-Cell dysfunction in Type 2 Diabetes is due to impaired function, defined as failure, or if chronic overstimulation of the ß-Cell that exceeds its capacity to synthesize and secrete insulin, defined as abuse, is the main abnormality in Type 2 Diabetes. These questions are important as they have direct implications for how to best prevent and treat Type 2 Diabetes.

Bariatric Surgery for Obesity

In this review, the authors discuss the indications for and the published outcomes of commonly performed bariatric procedures, including weight loss, perioperative morbidity and mortality, late complications, as well as the impact of bariatric surgery on comorbidities, cardiovascular risk, and mortality. They also briefly discuss the mechanisms by which bariatric/metabolic surgery causes such significant weight loss and health gain.

Metabolic Effects of Bariatric Surgery

BACKGROUND

Obesity can be defined as a chronic subcortical brain disease, as there is an important neurophysiological component to its etiology based on changes in the functioning of those areas of the brain controlling food intake and reward. Extensive metabolic changes accompany bariatric surgery-based treatment of obesity. Consequently, the term “metabolic” surgery is being increasingly adopted in relation to the beneficial effects these procedures have on chronic diseases like type 2 diabetes.

CONTENT

In the present review, we focus on the key biochemical and physiological changes induced by metabolic surgery and highlight the beneficial effects accrued systemically with the use of an organ-based approach. Understanding the impact on and interactions between the gut, brain, adipose tissue, liver, muscle, pancreas, and kidney is key to understanding the sum of the metabolic effects of these operations.

SUMMARY

Further mechanistic studies are essential to assess the true potential of metabolic surgery to treat metabolic comorbidities of obesity beyond type 2 diabetes. Approaches that may mitigate the metabolic side effects of surgery also require attention. Understanding the positive impact of metabolic surgery on metabolic health may result in a wider acceptance of this intervention as treatment for metabolic, comorbid conditions.

Is Mini-Gastric Bypass a Rational Approach for Type-2 Diabetes?

PURPOSE OF REVIEW

Morbid obesity and type-2 diabetes mellitus (T2DM) are both major public health problems. Bariatric surgery is a proven and effective treatment for these conditions; laparoscopic Roux-en-Y gastric bypass (RYGB) is currently the gold-standard treatment. One-anastomosis gastric bypass (OAGB) is described as a simpler, safer, and non-inferior alternative to RYGB to treat morbid obesity. Concerning T2DM, experts of the OAGB procedure report promising metabolic results with good long-term remission of T2DM; however, heterogeneity within the literature prompted us to analyze this issue.

RECENT FINDINGS

OAGB has gained popularity given its safety and long-term efficacy. Concerning the effect of OAGB for the treatment of T2DM, most reports involve non-controlled single-arm studies with heterogeneous methodologies and a few randomized controlled trials. However, this available literature supports the efficacy of OAGB for remission of T2DM in obese and non-obese patients. Two years after OAGB, the T2DM remission and improvement rate increased from 67 to 100%. The results were improved and stable in the long term. The 5-year T2DM remission rate increased from 82 to 84.4%. OAGB is non-inferior compared with RYGB and even superior to other accepted bariatric procedures, such as sleeve gastrectomy and adjustable gastric banding. OAGB is an efficient, safe, simple, and reversible procedure to treat T2DM. The literature reveals interesting results for T2DM remission in non-obese patients. High-level comparative studies are required to support these data.

Individualized Metabolic Surgery Score: Procedure Selection Based on Diabetes Severity

OBJECTIVE

To construct and validate a scoring system for evidence-based selection of bariatric and metabolic surgery procedures according to severity of type 2 diabetes (T2DM).

BACKGROUND

Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG) account for >95% of bariatric procedures in United States in patients with T2DM. To date, there is no validated model to guide procedure selection based on long-term glucose control in patients with T2DM.

METHODS

A total of 659 patients with T2DM who underwent RYGB and SG at an academic center in the United States and had a minimum 5-year follow-up (2005-2011) were analyzed to generate the model. The validation dataset consisted of 241 patients from an academic center in Spain where similar criteria were applied.

RESULTS

At median postoperative follow-up of 7 years (range 5-12), diabetes remission (HbA1C <6.5% off medications) was observed in 49% after RYGB and 28% after SG (P < 0.001). Four independent predictors of long-term remission including preoperative duration of T2DM (P < 0.0001), preoperative number of diabetes medications (P < 0.0001), insulin use (P = 0.002), and glycemic control (HbA1C < 7%) (P = 0.002) were used to develop the Individualized Metabolic Surgery (IMS) score using a nomogram. Patients were then categorized into 3 stages of diabetes severity. In mild T2DM (IMS score ≤25), both procedures significantly improved T2DM. In severe T2DM (IMS score >95), when clinical features suggest limited functional β-cell reserve, both procedures had similarly low efficacy for diabetes remission. There was an intermediate group, however, in which RYGB was significantly more effective than SG, likely related to its more pronounced neurohormonal effects. Findings were externally validated and procedure recommendations for each severity stage were provided.

CONCLUSIONS

This is the largest reported cohort (n = 900) with long-term postoperative glycemic follow-up, which, for the first time, categorizes T2DM into 3 validated severity stages for evidence-based procedure selection.

Metabolic Surgery in the Treatment Algorithm for Type 2 Diabetes: A Joint Statement by International Diabetes Organizations

BACKGROUND

Despite growing evidence that bariatric/metabolic surgery powerfully improves type 2 diabetes (T2D), existing diabetes treatment algorithms do not include surgical options.

AIM

The 2nd Diabetes Surgery Summit (DSS-II), an international consensus conference, was convened in collaboration with leading diabetes organizations to develop global guidelines to inform clinicians and policymakers about benefits and limitations of metabolic surgery for T2D.

METHODS

A multidisciplinary group of 48 international clinicians/scholars (75% nonsurgeons), including representatives of leading diabetes organizations, participated in DSS-II. After evidence appraisal (MEDLINE [1 January 2005-30 September 2015]), three rounds of Delphi-like questionnaires were used to measure consensus for 32 data-based conclusions. These drafts were presented at the combined DSS-II and 3rd World Congress on Interventional Therapies for Type 2 Diabetes (London, U.K., 28-30 September 2015), where they were open to public comment by other professionals and amended face-to-face by the Expert Committee.

RESULTS

Given its role in metabolic regulation, the gastrointestinal tract constitutes a meaningful target to manage T2D. Numerous randomized clinical trials, albeit mostly short/midterm, demonstrate that metabolic surgery achieves excellent glycemic control and reduces cardiovascular risk factors. On the basis of such evidence, metabolic surgery should be recommended to treat T2D in patients with class III obesity (BMI≥40 kg/m(2)) and in those with class II obesity (BMI 35.0-39.9 kg/m(2)) when hyperglycemia is inadequately controlled by lifestyle and optimal medical therapy. Surgery should also be considered for patients with T2D and BMI 30.0-34.9 kg/m(2) if hyperglycemia is inadequately controlled despite optimal treatment with either oral or injectable medications. These BMI thresholds should be reduced by 2.5 kg/m(2) for Asian patients.

CONCLUSIONS

Although additional studies are needed to further demonstrate long-term benefits, there is sufficient clinical and mechanistic evidence to support inclusion of metabolic surgery among antidiabetes interventions for people with T2D and obesity. To date, the DSS-II guidelines have been formally endorsed by 45 worldwide medical and scientific societies. Health care regulators should introduce appropriate reimbursement policies.

Recent advancements in bariatric/metabolic surgery

Obesity and type 2 diabetes mellitus (T2DM) are currently two pan‐endemic health problems worldwide and are associated with considerable increase in morbidity and mortality. Both diseases are closely related and very difficult to control by current medical treatment, including diet, drug therapy and behavioral modification. Bariatric surgery has proven successful in treating not just obesity but also in significantly decreasing overall obesity‐associated morbidities as well as improving quality of life in severely obese patients (body mass index [BMI] >35 kg/m²). A rapid increase in bariatric surgery started in the 2000s when the laparoscopic surgical technique was introduced into this field. Many new procedures had been developed and changed the face of modern bariatric surgery. Recently, bariatric surgery played as gastrointestinal metabolic surgery has been proposed as a new treatment modality for obesity‐related T2DM for patients with BMI >35 kg/m². Strong evidence has demonstrated that bariatric/metabolic surgery is an effective and durable treatment for obese T2DM patients. Bariatric/metabolic surgery is now becoming an important surgical division. The present article examines and discusses recent advancements in bariatric/metabolic surgery and covers four major fields: (i) the rapid increase in numbers and better safety; (ii) new procedures with better outcomes; (iii) from bariatric to metabolic surgery; and (iv) understanding the mechanisms and personalized treatment.

Mechanisms of weight loss and improved metabolism following bariatric surgery

Bariatric surgery is increasingly recognized as one of the most effective interventions to help patients achieve significant and sustained weight loss, as well as improved metabolic and overall health. Unfortunately, the cellular and physiological mechanisms by which bariatric surgery achieves weight loss have not been fully elucidated, yet are critical to understanding the central role of the intestinal tract in whole-body metabolism and to developing novel strategies for the treatment of obesity. In this review, we provide an overview of potential mechanisms contributing to weight loss, including effects on regulation of energy balance and both central and peripheral nervous system regulation of appetite and metabolism. Moreover, we highlight the importance of the gastrointestinal tract, including alterations in bile acid physiology, secretion of intestinally derived hormones, and the microbiome, as a potent mediator of improved metabolism in postbariatric patients.

Cost and Health Care Utilization Implications of Bariatric Surgery Versus Intensive Lifestyle and Medical Intervention for Type 2 Diabetes

OBJECTIVE

The aim of this study was to compare the cost and health care utilization of patients with obesity and type 2 diabetes mellitus (T2DM) randomized into either Roux-en-Y gastric bypass (RYGB) surgery or an intensive lifestyle and medical intervention (ILMI).

METHODS

This analysis (N = 745) is based on 2-year follow-up of a small randomized controlled trial (RCT); adult patients with obesity and T2DM were recruited between 2011 and 2012 from Kaiser Permanente Washington. Comparisons were made for patients randomized into either RYGB (N = 15) or ILMI (N = 17).

RESULTS

There were no significant cost savings for RYGB versus ILMI patients through the follow-up years. Pharmacy cost was lower for RYGB versus ILMI patients by about $900 in year 2 versus year 0; however, inpatient and emergency room costs were higher for surgery patients in follow-up years relative to year 0. Median total cost for nonrandomized patients was higher in year 0 and in year 2 compared to randomized patients.

CONCLUSIONS

Bariatric surgery is not cost saving in the short term. Moreover, the costs of patients who enter into RCTs of RYGB may differ from the costs of those who do not enter RCTs, suggesting use of caution when using such data to draw inferences about the general population with obesity.

Role of the Gut on Glucose Homeostasis: Lesson Learned from Metabolic Surgery

Purpose of Review

Bariatric surgery was initially intended to reduce weight, and only subsequently was the remission of type two diabetes (T2D) observed as a collateral event. At the moment, the term “metabolic surgery” is used to underline the fact that this type of surgery is performed specifically to treat diabetes and its metabolic complications, such as hyperlipidemia.

Recent Findings

Randomized, controlled studies have recently supported the use of bariatric surgery, and in particular of Roux-en-Y gastric bypass (RYGB) and biliopancreatic diversion (BPD) as an effective treatment for decompensated T2D. The lesson learned from these randomized and many other non-randomized clinical studies is that the stomach and the small intestine play a central role in glucose homeostasis. Bypassing the duodenum and parts of the jejunum exerts a substantial effect on insulin sensitivity and secretion. In fact, with BPD, nutrient transit bypasses duodenum, the entire jejunum and a small portion of the ileum, resulting in reversal of insulin sensitivity back to normal and reduction of insulin secretion, whereas RYGB has little effect on insulin resistance but increases insulin secretion. Hypotheses concerning the mechanism of action of metabolic surgery for diabetes remission vary from theories focusing on jejunal nutrient sensing, to incretin action, to the blunted secretion of putative insulin resistance hormone(s), to changes in the microbiota.

Summary

Whatever the mechanism, metabolic surgery has the undoubted merit of exposing the central role of the small intestine in insulin sensitivity and glucose homeostasis.

The role of bariatric surgery to treat diabetes: current challenges and perspectives

Bariatric surgery is emerging as a powerful weapon against severe obesity and type 2 diabetes mellitus (T2DM). Given its role in metabolic regulation, the gastrointestinal tract constitutes a meaningful target to treat T2DM, especially in light of accumulating evidence that surgery with gastrointestinal manipulations may result in T2DM remission (metabolic surgery). The major mechanisms mediating the weight loss-independent effects of bariatric surgery comprise effects on tissue-specific insulin sensitivity, β-cell function and incretin responses, changes in bile acid composition and flow, modifications of gut microbiota, intestinal glucose metabolism and increased brown adipose tissue metabolic activity. Shorter T2DM duration, better preoperative glycemic control and profound weight loss, have been associated with higher rates of T2DM remission and lower risk of relapse. In the short and medium term, a significant amount of weight is lost, T2DM may completely regress, and cardiometabolic risk factors are dramatically improved. In the long term, metabolic surgery may achieve durable weight loss, prevent T2DM and cancer, improve overall glycemic control while leading to significant rates of T2DM remission, and reduce total and cause-specific mortality. The gradient of efficacy for weight loss and T2DM remission comparing the four established surgical procedures is biliopancreatic diversion >Roux-en-Y gastric bypass >sleeve gastrectomy >laparoscopic adjustable gastric banding. According to recently released guidelines, bariatric surgery should be recommended in diabetic patients with class III obesity, regardless of their level of glycemic control, and patients with class II obesity with inadequately controlled T2DM despite lifestyle and optimal medical therapy. Surgery should also be considered in patients with class I obesity and inadequately controlled hyperglycemia despite optimal medical treatment.

Metabolic Surgery in the Treatment Algorithm for Type 2 Diabetes: a Joint Statement by International Diabetes Organizations

BACKGROUND

Despite growing evidence that bariatric/metabolic surgery powerfully improves type 2 diabetes (T2D), existing diabetes treatment algorithms do not include surgical options.

AIM

The 2nd Diabetes Surgery Summit (DSS-II), an international consensus conference, was convened in collaboration with leading diabetes organizations to develop global guidelines to inform clinicians and policymakers about benefits and limitations of metabolic surgery for T2D.

METHODS

A multidisciplinary group of 48 international clinicians/scholars (75% nonsurgeons), including representatives of leading diabetes organizations, participated in DSS-II. After evidence appraisal (MEDLINE [1 January 2005-30 September 2015]), three rounds of Delphi-like questionnaires were used to measure consensus for 32 data-based conclusions. These drafts were presented at the combined DSS-II and 3rd World Congress on Interventional Therapies for Type 2 Diabetes (London, U.K., 28-30 September 2015), where they were open to public comment by other professionals and amended face-to-face by the Expert Committee.

RESULTS

Given its role in metabolic regulation, the gastrointestinal tract constitutes a meaningful target to manage T2D. Numerous randomized clinical trials, albeit mostly short/midterm, demonstrate that metabolic surgery achieves excellent glycemic control and reduces cardiovascular risk factors. On the basis of such evidence, metabolic surgery should be recommended to treat T2D in patients with class III obesity (BMI ≥40 kg/m²) and in those with class II obesity (BMI 35.0-39.9 kg/m²) when hyperglycemia is inadequately controlled by lifestyle and optimal medical therapy. Surgery should also be considered for patients with T2D and BMI 30.0-34.9 kg/m² if hyperglycemia is inadequately controlled despite optimal treatment with either oral or injectable medications. These BMI thresholds should be reduced by 2.5 kg/m² for Asian patients.

CONCLUSIONS

Although additional studies are needed to further demonstrate long-term benefits, there is sufficient clinical and mechanistic evidence to support inclusion of metabolic surgery among antidiabetes interventions for people with T2D and obesity. To date, the DSS-II guidelines have been formally endorsed by 45 worldwide medical and scientific societies. Health care regulators should introduce appropriate reimbursement policies.

Type 2 diabetes remission rates 1-year post-Roux-en-Y gastric bypass and validation of the DiaRem score: the Ontario Bariatric Network experience

Roux-en-Y gastric bypass (RYGB) is associated with the remission of type 2 diabetes mellitus (DM). There are a number of scoring systems available that help predict type 2 diabetes remission rates after bariatric surgery; however, relatively few have been validated externally. The DiaRem score, comprised of four preoperative variables (age, haemoglobin A1c [HbA1c], sulfonylurea and insulin-sensitizing agent use and insulin use), allows for the identification of patients who are most likely to have DM remission following RYGB. Our primary objective was to determine the variables predictive of DM remission 1 year post-RYGB, determine how well the DiaRem score predicts DM remission 1 year post-RYGB and identify the optimal cut-off DiaRem score. The study is based on results of RYGB performed across multiple centres in Ontario, Canada, overseen by the Centre for Surgical Invention and Innovation in Hamilton, with direction from the Ontario Bariatric Network. Regression analysis was used to determine the predictive value of demographic and clinical variables and that of the DiaRem score. The optimal DiaRem cut-off score was determined using sensitivity and specificity analysis. Of 3874 patients in the Ontario Bariatric Registry between January 2010 and February 2015, 915 had complete 1-year follow-up data. Among these, 15 were not classified as having DM at baseline and were excluded. Of the remaining 900 patients with type 2 diabetes and who underwent RYGB surgery, 333 (37.0%) had DM remission at 1-year follow-up. Three of four DiaRem variables (age, HbA1c, insulin use), in addition to use of any hypoglycaemic agent, were associated with DM remission. DiaRem score had moderate predictive value. A DiaRem score cut-off of <5 had a sensitivity of 71.8% and specificity of 71.3%. This study provides guidance to clinicians in using the DiaRem score to inform the selection and prioritization of patients to ensure timely access to bariatric surgery for those who are likely to benefit the most.

The Gut as an Endocrine Organ: Role in the Regulation of Food Intake and Body Weight

Obesity and its related complications remain a major threat to public health. Efforts to reduce the prevalence of obesity are of paramount importance in improving population health. Through these efforts, our appreciation of the role of gut-derived hormones in the management of body weight has evolved and manipulation of this system serves as the basis for our most effective obesity interventions.

PURPOSE OF THE REVIEW

We review current understanding of the enteroendocrine regulation of food intake and body weight, focusing on therapies that have successfully embraced the physiology of this system to enable weight loss.

RECENT FINDINGS

In addition to the role of gut hormones in the regulation of energy homeostasis, our understanding of the potential influence of enteroendocrine peptides in food reward pathways is evolving. So too is the role of gut derived hormones on energy expenditure. Gut-derived hormones have the ability to alter feeding behavior. Certain obesity therapies already manipulate this system; however, our evolving understanding of the effects of enteroendocrine signals on hedonic aspects of feeding and energy expenditure may be crucial in identifying future obesity therapies.

High baseline C-reactive protein levels predict partial type 2 diabetes mellitus remission after biliopancreatic diversion

BACKGROUND AND AIMS

Several studies demonstrated that surgery can improve inflammation parameters, such as C-reactive protein (CRP). Few biomarkers have been investigated to potentially predict type 2 diabetes mellitus (T2DM) remission. We aimed at determining whether pre-surgery serum CRP levels could predict T2DM remission after 3 years in patients undergoing bariatric surgery, especially biliopancreatic diversion (BPD).

METHODS AND RESULTS

This study was conducted from 2007 to 2009 at the Surgical Department of the University of Genoa, Italy. Forty-four patients with T2DM undergoing BPD (n = 38) or Roux-en-Y gastric bypass (n = 6) were enrolled. The primary endpoint was to evaluate whether pre-surgery CRP levels could predict T2DM partial remission at 3-year follow-up. Secondary endpoints were to assess whether glycaemic, lipid, and inflammatory parameters modified during the follow-up. At baseline, patients with T2DM ranged from overweight to morbid obesity, had mild dyslipidaemia, and a low-grade inflammation. Bariatric surgery improved body weight, lipid and glycaemic profile both at 1- and 3-year follow-up. Pre-surgery CRP levels progressively decreased at 1- and 3-year follow-up. Among inflammatory pre-surgery parameters, only high CRP levels were shown to predict T2DM partial remission after 3 years. Multivariate analysis confirmed the predictive value of pre-surgery CRP levels independently of age, gender, type of surgery, and body mass index.

CONCLUSION

Bariatric surgery, in particular BPD, improved both metabolic and inflammatory biomarkers at 1- and 3-year follow-up. Pre-surgery high CRP levels predicted 3-year T2DM partial remission, indicating a promising target population to be especially treated with BPD.

Bariatric surgery for obesity and metabolic disorders: state of the art

Obesity is one of the most important public health conditions worldwide. Bariatric surgery for severe obesity is an effective treatment that results in the improvement and remission of many obesity-related comorbidities, as well as providing sustained weight loss and improvement in quality of life. Contemporary bariatric operations include Roux-en-Y gastric bypass, sleeve gastrectomy, adjustable gastric band and the duodenal switch. The vast majority of these procedures are now performed using laparoscopic technique, the main advantages of which include rapid recovery, the reduction of postoperative pain and the reduction of wound-related complications, compared with open surgery. Contemporary bariatric surgery is now safe, with a mortality of three in 1,000 patients; however, all bariatric operations are associated with their own unique short-term and long-term nutritional and procedural-related complications. Type 2 diabetes mellitus (T2DM) is the most studied metabolic disorder associated with obesity, with data demonstrating that improvement and remission of T2DM in patients with obesity is superior after bariatric surgery compared with conventional medical therapy. Bariatric surgery is now a part of some treatment algorithms for the medical management of patients with T2DM and severe obesity. New, minimally invasive and endoscopic devices for the treatment of obesity have now been approved in the USA, which will expand the treatment options for individuals with obesity.

Bariatric Surgery versus Intensive Medical Therapy for Diabetes - 5-Year Outcomes

BACKGROUND

Long-term results from randomized, controlled trials that compare medical therapy with surgical therapy in patients with type 2 diabetes are limited.

METHODS

We assessed outcomes 5 years after 150 patients who had type 2 diabetes and a body-mass index (BMI; the weight in kilograms divided by the square of the height in meters) of 27 to 43 were randomly assigned to receive intensive medical therapy alone or intensive medical therapy plus Roux-en-Y gastric bypass or sleeve gastrectomy. The primary outcome was a glycated hemoglobin level of 6.0% or less with or without the use of diabetes medications.

RESULTS

Of the 150 patients who underwent randomization, 1 patient died during the 5-year follow-up period; 134 of the remaining 149 patients (90%) completed 5 years of follow-up. At baseline, the mean (±SD) age of the 134 patients was 49±8 years, 66% were women, the mean glycated hemoglobin level was 9.2±1.5%, and the mean BMI was 37±3.5. At 5 years, the criterion for the primary end point was met by 2 of 38 patients (5%) who received medical therapy alone, as compared with 14 of 49 patients (29%) who underwent gastric bypass (unadjusted P=0.01, adjusted P=0.03, P=0.08 in the intention-to-treat analysis) and 11 of 47 patients (23%) who underwent sleeve gastrectomy (unadjusted P=0.03, adjusted P=0.07, P=0.17 in the intention-to-treat analysis). Patients who underwent surgical procedures had a greater mean percentage reduction from baseline in glycated hemoglobin level than did patients who received medical therapy alone (2.1% vs. 0.3%, P=0.003). At 5 years, changes from baseline observed in the gastric-bypass and sleeve-gastrectomy groups were superior to the changes seen in the medical-therapy group with respect to body weight (-23%, -19%, and -5% in the gastric-bypass, sleeve-gastrectomy, and medical-therapy groups, respectively), triglyceride level (-40%, -29%, and -8%), high-density lipoprotein cholesterol level (32%, 30%, and 7%), use of insulin (-35%, -34%, and -13%), and quality-of-life measures (general health score increases of 17, 16, and 0.3; scores on the RAND 36-Item Health Survey ranged from 0 to 100, with higher scores indicating better health) (P<0.05 for all comparisons). No major late surgical complications were reported except for one reoperation.

CONCLUSIONS

Five-year outcome data showed that, among patients with type 2 diabetes and a BMI of 27 to 43, bariatric surgery plus intensive medical therapy was more effective than intensive medical therapy alone in decreasing, or in some cases resolving, hyperglycemia. (Funded by Ethicon Endo-Surgery and others; STAMPEDE ClinicalTrials.gov number, NCT00432809 .).

Intestinal Glycolysis Visualized by FDG PET/CT Correlates With Glucose Decrement After Gastrectomy

Gastrectomy method is known to influence glucose homeostasis. ¹⁸F-fluoro-2-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) images acquired after gastrectomy often reveals newly developed physiological small bowel uptake. We correlated newly developed small bowel FDG uptake and glucose homeostasis in postgastrectomy gastric cancer patients. We retrospectively analyzed 239 patients without diabetes who underwent staging and follow-up FDG PET/CT scanning before and after gastrectomy for gastric cancer. Postoperative small bowel glycolysis was quantified by recording intestinal total lesion glycolysis (TLG). TLG was assessed with regard to surgical method (Billroth I, Billroth II [BII], Roux-en-Y [RY]), fasting glucose decrement (≥10 mg/dL), and other clinical factors. Patients' weight, fasting glucose, cholesterol, TLG, and body fat levels significantly decreased after surgery. The glucose decrement was significantly associated with fasting glucose, surgical methods, total cholesterol, TLG, and total body fat on univariate analysis. Multivariate analysis showed that BII surgery (odds ratio 6.51) and TLG (odds ratio 3.17) were significantly correlated with glucose decrement. High small bowel glycolysis (TLG >42.0 g) correlated with glucose decrement in RY patients. Newly developed small bowel glycolysis on postgastrectomy FDG PET/CT scanning is correlated with a glucose decrement. These findings suggest a potential role of FDG PET/CT scanning in the evaluation of small bowel glycolysis and glucose control.

PRELIMINARY ANALYSIS OF INTERLEUKIN-6 CHANGES IN PRE- AND POSTOPERATIVE IN DIABETIC PATIENTS WITH BMI<35 SUBMITTED TO PARTIAL DUODENAL SWITCH

Background:

Studies related to obesity have shown association with metabolic syndrome. Data showing that obesity is capable to cause low grade chronic inflammation, without its classic signs and symptoms, call attention to researches to study different cells types and the mechanism of the inflammatory process.

Aim:

To evaluate the variation of glycated hemoglobin (HbA1c) and the pro-inflammatory cytokine interleukin-6 (IL6) in diabetic patients with BMI <35 kg/m² in the pre and postoperative of partial duodenal switch.

Method:

Nine patients were studied before and one year after the operation and the variation of the serum IL6 was measured by Elisa. The changes of HbA1c were also registered.

Results:

The pre-operative IL6 levels reached 65,50436±2,911993 pg/ml and one year after de operation 39,47739±3,410057 and the HbA1c average of 10,67 and 5.8 in the same period.

Conclusion:

The partial duodenal switch was efficient to control one year after the procedure the chronic inflammatory process caused by the diabetes mellitus type 2 with BMI <35 by dropping the IL6 levels and bringing the HbA1c to normal.

Altered glucose profiles and risk for hypoglycaemia during oral glucose tolerance testing in pregnancies after gastric bypass surgery

AIMS/HYPOTHESIS

A history of gastric bypass surgery can influence the results of the OGTT recommended during pregnancy. Therefore, we compared OGTT glucose kinetics and pregnancy outcome between pregnant gastric bypass patients and BMI-matched, lean and obese controls.

METHODS

Medical records were used to collect data on glucose measurements during the 2 h 75 g OGTT as well as on pregnancy and fetal outcome for 304 women (n = 76 per group, matched for age and date of delivery).

RESULTS

Women after bariatric surgery had lower fasting glucose levels compared with lean, obese and BMI-matched controls, and showed altered postprandial glucose kinetics, including a rise at 60 min followed by hypoglycaemia with serum glucose of <3.34 mmol/l (which occurred in 54.8%). Moreover, their risk of pre-eclampsia or gestational hypertension was reduced, with an increased risk of delivering small for gestational age infants.

CONCLUSIONS/INTERPRETATION

Alternative strategies to accurately define impaired glucose metabolism in pregnancies after bariatric surgery should be explored.

Key Questions for Translation of FFA Receptors: From Pharmacology to Medicines

The identification of fatty acids as ligands for the G-protein coupled free fatty acid (FFA) receptor family over 10 years ago led to intensive chemistry efforts to find small-molecule ligands for this class of receptors. Identification of potent, selective modulators of the FFA receptors and their utility in medicine has proven challenging, in part due to their complex pharmacology. Nevertheless, ligands have been identified that are sufficient for exploring the therapeutic potential of this class of receptors in rodents and, in the case of FFA1, FFA2, FFA4, and GPR84, also in humans. Expression profiling, the phenotyping of FFA receptor knockout mice, and the results of studies exploring the effects of these ligands in rodents have uncovered a number of indications where engagement of one or a combination of FFA receptors might provide some clinical benefit in areas including diabetes, inflammatory bowel syndrome, Alzheimer's, pain, and cancer. In this chapter, we will review the clinical potential of modulating FFA receptors based on preclinical and in some cases clinical studies with synthetic ligands. In particular, key aspects and challenges associated with small-molecule ligand identification and FFA receptor pharmacology will be addressed with a view of the hurdles that need to be overcome to fully understand the potential of the receptors as therapeutic targets.

Metabolic Surgery for Type 2 Diabetes Mellitus: Experience from Asia

Type 2 diabetes mellitus (T2DM) is a current global health priority and Asia is the epicenter of this epidemic disease. Unlike in the west, where older population is most affected, the burden of diabetes in Asian countries is disproportionately high in young to middle-age adults. The incidence of diabetic nephropathy is alarmingly high in patients with early onset T2DM, especially in those with poor glycemic control. How to control this chronic and debilitating disease is currently a very important health issue in Asia. Bariatric surgery has proven successful in treating not just obesity but also T2DM in morbid obese patients (body mass index [BMI] >35 kg/m²). Gastrointestinal metabolic surgery recently has been proposed as a new treatment modality for obesity related T2DM for patients with BMI <35 kg/m². Many studies from Asia reported promising results of metabolic surgery to treat obese patients with T2DM which is not well controlled. It has been demonstrated that changes in gastrointestinal hormone secretion after gastrointestinal surgery would favor an early improvement of T2DM in Asians. New procedures have also been designed and proposed specifically for the treatment of diabetes in Asia. This article examines clinical trial data and accepted algorithms with a view toward elucidating the application of metabolic surgery for the treatment of T2DM in the Asia. We propose a systematic approach to surgical treatment, addressing current evidences, patient selection, procedure of choice, and timing and guideline for new procedures.

Surgical Treatment of Metabolic Syndrome

BACKGROUND

Bariatric surgery is gastrointestinal surgery for weight control, and metabolic surgery refers to the use of surgery to primarily and purposely treat type 2 diabetes mellitus (T2DM)/metabolic syndrome mellitus.

METHODS

The most recent literature was reviewed for surgery and T2DM in a non-systematic fashion.

RESULTS

Roux-Y gastric bypass, biliopancreatic diversion with duodenal switch, and sleeve gastrectomy (SG) are the dominant procedures today. SG is emerging as the most popular operation worldwide. Laparoscopy has made metabolic surgery as safe as other common abdominal procedures. A BMI > 60 kg/m², however, exposes a significantly higher perioperative risk. Most patients experience a sustained improvement of glycemic control with subsequent reduction of cardiovascular events. The remission rates depend on the severity and duration of diabetes. Prevention of long-term nutritional deficits and monitoring of metabolism require lifelong medical surveillance of the patients.

CONCLUSIONS

The profound impact of weight reduction surgery on glucose metabolism explains the growing interest in treating T2DM by surgical means. Metabolic surgery is a safe option for carefully selected patients with metabolic syndrome.

Change in fracture risk and fracture pattern after bariatric surgery: nested case-control study

OBJECTIVE

 To investigate whether bariatric surgery increases the risk of fracture.

DESIGN

 Retrospective nested case-control study.

SETTING

 Patients who underwent bariatric surgery in the province of Quebec, Canada, between 2001 and 2014, selected using healthcare administrative databases.

PARTICIPANTS

 12 676 patients who underwent bariatric surgery, age and sex matched with 38 028 obese and 126 760 non-obese controls.

MAIN OUTCOME MEASURES

 Incidence and sites of fracture in patients who had undergone bariatric surgery compared with obese and non-obese controls. Fracture risk was also compared before and after surgery (index date) within each group and by type of surgery from 2006 to 2014. Multivariate conditional Poisson regression models were adjusted for fracture history, number of comorbidities, sociomaterial deprivation, and area of residence.

RESULTS

 Before surgery, patients undergoing bariatric surgery (9169 (72.3%) women; mean age 42 (SD 11) years) were more likely to fracture (1326; 10.5%) than were obese (3065; 8.1%) or non-obese (8329; 6.6%) controls. A mean of 4.4 years after surgery, bariatric patients were more susceptible to fracture (514; 4.1%) than were obese (1013; 2.7%) and non-obese (3008; 2.4%) controls. Postoperative adjusted fracture risk was higher in the bariatric group than in the obese (relative risk 1.38, 95% confidence interval 1.23 to 1.55) and non-obese (1.44, 1.29 to 1.59) groups. Before surgery, the risk of distal lower limb fracture was higher, upper limb fracture risk was lower, and risk of clinical spine, hip, femur, or pelvic fractures was similar in the bariatric and obese groups compared with the non-obese group. After surgery, risk of distal lower limb fracture decreased (relative risk 0.66, 0.56 to 0.78), whereas risk of upper limb (1.64, 1.40 to 1.93), clinical spine (1.78, 1.08 to 2.93), pelvic, hip, or femur (2.52, 1.78 to 3.59) fractures increased. The increase in risk of fracture reached significance only for biliopancreatic diversion.

CONCLUSIONS

 Patients undergoing bariatric surgery were more likely to have fractures than were obese or non-obese controls, and this risk remained higher after surgery. Fracture risk was site specific, changing from a pattern associated with obesity to a pattern typical of osteoporosis after surgery. Only biliopancreatic diversion was clearly associated with fracture risk; however, results for Roux-en-Y gastric bypass and sleeve gastrectomy remain inconclusive. Fracture risk assessment and management should be part of bariatric care.

Improvements in glycemic control after gastric bypass occur despite persistent adipose tissue inflammation

OBJECTIVE

Type 2 diabetes commonly goes into remission following Roux-en-Y gastric bypass (RYGB). As the mechanisms remain incompletely understood, a reduction in adipose tissue inflammation may contribute to these metabolic improvements. Therefore, whether RYGB reduces adipose tissue inflammation compared with equivalent weight loss from an intensive lifestyle intervention was investigated.

METHODS

Sixteen people with obesity and type 2 diabetes were randomized to RYGB or lifestyle intervention. Fasting blood and subcutaneous abdominal adipose tissue were obtained before and after the loss of ∼7% of baseline weight. Adipose tissue inflammation was assessed by whole-tissue gene expression and flow cytometry-based quantification of tissue leukocytes.

RESULTS

At 7% weight loss, insulin and metformin use were reduced among the RYGB but not the Lifestyle cohort, while fasting glucose and insulin declined in both. Adipose tissue inflammation increased modestly after RYGB and to a similar extent following nonsurgical weight loss. In both groups, the number of neutrophils increased severalfold (P < 0.001), mRNA levels of the proinflammatory cytokine interleukin-1β increased (P = 0.037), and mRNA expression of the anti-inflammatory and insulin-sensitizing adipokine adiponectin decreased (P = 0.010).

CONCLUSIONS

A reduction in adipose tissue inflammation is not one of the acute weight loss-independent mechanisms through which RYGB exerts its antidiabetes effects.

Mechanisms of surgical control of type 2 diabetes: GLP-1 is the key factor-Maybe

Bariatric surgery is the most effective treatment for obesity and diabetes. The 2 most commonly performed weight-loss procedures, Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy, improve glycemic control in patients with type 2 diabetes independent of weight loss. One of the early hypotheses raised to explain the immediate antidiabetic effect of RYGB was that rapid delivery of nutrients from the stomach pouch into the distal small intestine enhances enteroinsular signaling to promote insulin signaling. Given the tenfold increase in postmeal glucagon-like peptide-1 (GLP-1) response compared to unchanged integrated levels of postprandial glucose-dependent insulinotropic peptide after RYGB, enhanced meal-induced insulin secretion after this procedure was thought to be the result of elevated glucose and GLP-1 levels. In this contribution to the larger point-counterpoint debate about the role of GLP-1 after bariatric surgery, most of the focus will be on RYGB.