Surgical treatment of obesity and its effect on diabetes: 10-y follow-up

Reversing pancreatic β-cell dedifferentiation in the treatment of type 2 diabetes

The maintenance of glucose homeostasis is fundamental for survival and health. Diabetes develops when glucose homeostasis fails. Type 2 diabetes (T2D) is characterized by insulin resistance and pancreatic β-cell failure. The failure of β-cells to compensate for insulin resistance results in hyperglycemia, which in turn drives altered lipid metabolism and β-cell failure. Thus, insulin secretion by pancreatic β-cells is a primary component of glucose homeostasis. Impaired β-cell function and reduced β-cell mass are found in diabetes. Both features stem from a failure to maintain β-cell identity, which causes β-cells to dedifferentiate into nonfunctional endocrine progenitor-like cells or to trans-differentiate into other endocrine cell types. In this regard, one of the key issues in achieving disease modification is how to reestablish β-cell identity. In this review, we focus on the causes and implications of β-cell failure, as well as its potential reversibility as a T2D treatment.

Genetic and pharmacologic inhibition of ALDH1A3 as a treatment of β-cell failure

Type 2 diabetes (T2D) is associated with β-cell dedifferentiation. Aldehyde dehydrogenase 1 isoform A3 (ALHD1A3) is a marker of β-cell dedifferentiation and correlates with T2D progression. However, it is unknown whether ALDH1A3 activity contributes to β-cell failure, and whether the decrease of ALDH1A3-positive β-cells (A+) following pair-feeding of diabetic animals is due to β-cell restoration. To tackle these questions, we (i) investigated the fate of A+ cells during pair-feeding by lineage-tracing, (ii) somatically ablated ALDH1A3 in diabetic β-cells, and (iii) used a novel selective ALDH1A3 inhibitor to treat diabetes. Lineage tracing and functional characterization show that A+ cells can be reconverted to functional, mature β-cells. Genetic or pharmacological inhibition of ALDH1A3 in diabetic mice lowers glycemia and increases insulin secretion. Characterization of β-cells following ALDH1A3 inhibition shows reactivation of differentiation as well as regeneration pathways. We conclude that ALDH1A3 inhibition offers a therapeutic strategy against β-cell dysfunction in diabetes.

The effectiveness of lifestyle interventions for diabetes remission on patients with type 2 diabetes mellitus: A systematic review and meta-analysis

BACKGROUND

Conventional wisdom affirmed that diabetes was irreversible, but current research shows that lifestyle interventions may achieve diabetes remission among patients with type 2 diabetes mellitus. Recently, many original studies have examined the effectiveness of lifestyle interventions. However, great heterogeneity in intervention approaches resulted in inconsistent intervention effects.

AIMS

The aim of this study was to determine the effectiveness of lifestyle interventions for diabetes remission among patients with type 2 diabetes mellitus.

METHODS

PubMed, CINAHL, Embase, Web of Science Core Collection, and Cochrane Library were searched for relevant articles from their inceptions to March 26, 2021. Reference lists and a relevant journal were searched manually as well. Both randomized controlled trials and quasi-experimental studies were included. The quantitative data extracted from the selected studies included diabetes remission rate, weight, and quality of life score. The risk of bias was assessed by the Cochrane and Joanna Briggs Institute's tool. RevMan version 5.3. was used to carry out the meta-analysis.

RESULTS

This systematic review included 12 studies involving 3997 patients with type 2 diabetes mellitus. Lifestyle interventions included in the studies were mainly divided into diet-only interventions and diet combined with physical activity interventions. Among them, there were three types of diet: (1) low-energy diet, (2) low carbohydrate diet, and (3) Mediterranean diet. Moderate-intensity aerobic and resistance physical activity, walking, and maintaining habitual physical activity were the three types of physical activity interventions employed in the included studies. The results indicated that lifestyle interventions were effective for achieving diabetes remission, reducing weight, and improving quality of life in patients with type 2 diabetes mellitus.

LINKING EVIDENCE TO ACTION

Lifestyle interventions were associated with significant effects on diabetes remission, reducing weight, and improving quality of life. As an important part of lifestyle interventions, diet and physical activity have a significant effect on blood glucose and weight control in patients with type 2 diabetes mellitus. It is therefore suggested that the contents of lifestyle interventions should focus on diet and physical activity.

Endoscopic gastroplasty versus laparoscopic sleeve gastrectomy: a noninferiority propensity score-matched comparative study

BACKGROUND AND AIMS

Endoscopic bariatric therapies are less-invasive alternatives to bariatric surgery, and endoscopic gastroplasty (ESG) represents the latest evolution. This study aims to compare weight loss, safety, and comorbidity resolution of ESG compared with laparoscopic sleeve gastrectomy (LSG).

METHODS

This was a propensity score-matched study of patients who underwent ESG or LSG. Primary outcome was weight loss at 6, 12, 24, and 36 months. A noninferiority margin of 10% total weight loss (%TWL) was used. Secondary outcomes were safety and comorbidity resolution.

RESULTS

A 1:1 propensity score match yielded 3018 patient pairs. Average age and body mass index (BMI) were 34 ± 10 years and 33 ± 3 kg/m², respectively, and 89% were women. Mean percentage of excess weight loss at 1, 2, and 3 years after ESG was 77.1% ± 24.6%, 75.2% ± 47.9%, and 59.7% ± 57.1%, respectively. Mean percentage of excess weight loss at 1, 2, and 3 years after LSG was 95.1% ± 20.5%, 93.6% ± 31.3%, and 74.3% ± 35.2%, respectively. The mean difference in %TWL was 9.7% (95% confidence interval [CI], 6.9-11.8; P < .001), 6.0% (95% CI, -2.0 to 9.4; P < .001), and 4.8% (95% CI, -1.5 to 8.7; P < .001) at 1, 2, and 3 years, respectively. Noninferiority was demonstrated at all follow-up visits. Fourteen ESG patients developed adverse events (.5%) versus 10 LSG patients (.3%). Comorbidity remission rates after ESG versus LSG were 64% versus 82% for diabetes, 66% versus 64% for dyslipidemia, and 51% versus 46% for hypertension, respectively. Eighty ESG patients (2.7%) underwent revision to LSG for insufficient weight loss or weight regain, and 28 had resuturing after primary ESG (.9%).

CONCLUSIONS

ESG induces noninferior weight loss to LSG with similar comorbidity resolution and safety profiles.

Reversal and Remission of T2DM - An Update for Practitioners

Over the past 50 years, many countries around the world have faced an unchecked pandemic of obesity and type 2 diabetes (T2DM). As best practice treatment of T2DM has done very little to check its growth, the pandemic of diabesity now threatens to make health-care systems economically more difficult for governments and individuals to manage within their budgets. The conventional view has been that T2DM is irreversible and progressive. However, in 2016, the World Health Organization (WHO) global report on diabetes added for the first time a section on diabetes reversal and acknowledged that it could be achieved through a number of therapeutic approaches. Many studies indicate that diabetes reversal, and possibly even long-term remission, is achievable, belying the conventional view. However, T2DM reversal is not yet a standardized area of practice and some questions remain about long-term outcomes. Diabetes reversal through diet is not articulated or discussed as a first-line target (or even goal) of treatment by any internationally recognized guidelines, which are mostly silent on the topic beyond encouraging lifestyle interventions in general. This review paper examines all the sustainable, practical, and scalable approaches to T2DM reversal, highlighting the evidence base, and serves as an interim update for practitioners looking to fill the practical knowledge gap on this topic in conventional diabetes guidelines.

Quantifying Remission Probability in Type 2 Diabetes Mellitus

Type 2 diabetes mellitus (T2DM) is a chronic progressive disorder and is associated with significant morbidity and mortality. The concept of T2DM remission and the reversal of diabetic parameters to normal levels has been gaining momentum over the past years. T2DM remission is increasingly being recognized by various global guidelines. Multiple models have been developed and validated for quantifying the extent of remission achieved. Based on favorable clinical evidence, T2DM remission can be considered as the therapeutic goal in diabetes management and, in select cases, as an alternative to expensive treatment options, which can be burdensome as T2DM progresses. This narrative review discusses the available strategies, such as lifestyle interventions, physical activity, bariatric surgery, medical nutrition therapy, and non-insulin glucose-lowering medications, for achieving T2DM remission. Although the concept of T2DM remission has emerged as a real-world option, effective implementation in routine clinical practice may not be feasible until long-term studies prove the efficacy of different approaches in this regard.

Epidemiology of type 2 diabetes remission in Scotland in 2019: A cross-sectional population-based study

BACKGROUND

Clinical pathways are changing to incorporate support and appropriate follow-up for people to achieve remission of type 2 diabetes, but there is limited understanding of the prevalence of remission in current practice or patient characteristics associated with remission.

METHODS AND FINDINGS

We carried out a cross-sectional study estimating the prevalence of remission of type 2 diabetes in all adults in Scotland aged ≥30 years diagnosed with type 2 diabetes and alive on December 31, 2019. Remission of type 2 diabetes was assessed between January 1, 2019 and December 31, 2019. We defined remission as all HbA1c values <48 mmol/mol in the absence of glucose-lowering therapy (GLT) for a continuous duration of ≥365 days before the date of the last recorded HbA1c in 2019. Multivariable logistic regression in complete and multiply imputed datasets was used to examine characteristics associated with remission. Our cohort consisted of 162,316 individuals, all of whom had at least 1 HbA1c ≥48 mmol/mol (6.5%) at or after diagnosis of diabetes and at least 1 HbA1c recorded in 2019 (78.5% of the eligible population). Over half (56%) of our cohort was aged 65 years or over in 2019, and 64% had had type 2 diabetes for at least 6 years. Our cohort was predominantly of white ethnicity (74%), and ethnicity data were missing for 19% of the cohort. Median body mass index (BMI) at diagnosis was 32.3 kg/m2. A total of 7,710 people (4.8% [95% confidence interval [CI] 4.7 to 4.9]) were in remission of type 2 diabetes. Factors associated with remission were older age (odds ratio [OR] 1.48 [95% CI 1.34 to 1.62] P < 0.001) for people aged ≥75 years compared to 45 to 54 year group), HbA1c <48 mmol/mol at diagnosis (OR 1.31 [95% CI 1.24 to 1.39] P < 0.001) compared to 48 to 52 mmol/mol), no previous history of GLT (OR 14.6 [95% CI 13.7 to 15.5] P < 0.001), weight loss from diagnosis to 2019 (OR 4.45 [95% CI 3.89 to 5.10] P < 0.001) for ≥15 kg of weight loss compared to 0 to 4.9 kg weight gain), and previous bariatric surgery (OR 11.9 [95% CI 9.41 to 15.1] P < 0.001). Limitations of the study include the use of a limited subset of possible definitions of remission of type 2 diabetes, missing data, and inability to identify self-funded bariatric surgery.

CONCLUSIONS

In this study, we found that 4.8% of people with type 2 diabetes who had at least 1 HbA1c ≥48 mmol/mol (6.5%) after diagnosis of diabetes and had at least 1 HbA1c recorded in 2019 had evidence of type 2 diabetes remission. Guidelines are required for management and follow-up of this group and may differ depending on whether weight loss and remission of diabetes were intentional or unintentional. Our findings can be used to evaluate the impact of future initiatives on the prevalence of type 2 diabetes remission.

Improving vitamin D status in bariatric surgery subjects with monthly high-dose ergocalciferol

Background: Vitamin D insufficiency is common before and after bariatric surgery. Optimal supplementation to treat vitamin D insufficiency is not clearly defined. Objective: Determine if serum 25 (OH) D levels improve by the consumption of an additional monthly ergocalciferol supplement by subjects after bariatric surgery. Study design: Thirty-two subjects were randomly divided to receive an additional 100,000 IUs of ergocalciferol monthly after bariatric surgery (n=10) or standard level vitamin D supplement after bariatric surgery (n=22). Serum 25 (OH) D, calcium, and hemoglobin A1c levels were measured preoperatively and one year after bariatric surgery. Results: Mean changes in BMI at 1-year post-operation was -18.12±6.46 kg/m² in the control group versus -18.84±4.7 kg/m²; p=0.638 in the vitamin D group. One year after bariatric surgery, the mean changes from baseline in vitamin D levels were 2.69±9.4 and 12.4±17.0 ng/mL in control and intervention groups, respectively. The treated group showed a marginally higher mean increase in Vitamin D than the control group, p=0.059. Other mean changes at 1-year post-surgery that were not significantly different include calcium -0.264±0.45 and -0.21±0.509 mg/dl in control and intervention groups, respectively and Hgb A1c -1.0±1.21 and -0.95±0.071% in control and intervention groups, respectively. Conclusion: This study showed 100,000 IUs ergocalciferol once a month is a safe and effective treatment for vitamin D insufficiency in most patients having bariatric surgery.

Preoperative Bariatric Surgery Predictors of Type 2 Diabetes Remission

Obesity represents a significant proportion of the global public health burden, with the World Health Organization (WHO) estimating more than 600 million people are affected worldwide. Unfortunately, the epidemic of obesity is linked to the increased prevalence of associated metabolic diseases such as type 2 diabetes mellitus (T2DM). Bariatric surgery as an intervention has been shown to provide sustainable weight loss, and also leads to superior short- and long-term metabolic benefits including T2DM remission. Despite this added advantage conferred by bariatric surgery, emerging evidence has shown that not all patients with T2DM achieve remission postoperatively. As such, to improve patient selection and optimize preoperative counselling, research has focused on the preoperative predictors of T2DM remission following bariatric surgery. Herein, we provide a critical review of the current literature addressing preoperative predictors of T2DM remission and highlight the current gaps in the literature. The review comprised a multistage advanced electronic search of the Ovid/Medline, Embase, and Cochrane online libraries to identify available studies published over the last decade.

Exercise-nutrient interactions for improved postprandial glycemic control and insulin sensitivity

Type 2 diabetes (T2D) is a rapidly growing yet largely preventable chronic disease. Exaggerated increases in blood glucose concentration following meals is a primary contributor to many long-term complications of the disease that decrease quality of life and reduce lifespan. Adverse health consequences also manifest years prior to the development of T2D due to underlying insulin resistance and exaggerated postprandial concentrations of the glucose-lowering hormone insulin. Postprandial hyperglycemic and hyperinsulinemic excursions can be improved by exercise, which contributes to the well-established benefits of physical activity for the prevention and treatment of T2D. The aim of this review is to describe the postprandial dysmetabolism that occurs in individuals at risk for and with T2D, and highlight how acute and chronic exercise can lower postprandial glucose and insulin excursions. In addition to describing the effects of traditional moderate-intensity continuous exercise on glycemic control, we highlight other forms of activity including low-intensity walking, high-intensity interval exercise, and resistance training. In an effort to improve knowledge translation and implementation of exercise for maximal glycemic benefits, we also describe how timing of exercise around meals and post-exercise nutrition can modify acute and chronic effects of exercise on glycemic control and insulin sensitivity. Novelty: Exaggerated postprandial blood glucose and insulin excursions are associated with disease risk. Both a single session and repeated sessions of exercise improve postprandial glycemic control in individuals with and without T2D. The glycemic benefits of exercise can be enhanced by considering the timing and macronutrient composition of meals around exercise.

Ockham's razor and the metabolic syndrome

The broad effects of bariatric/metabolic surgery on virtually every tissue and organ system remain unexplained. Weight loss, although a major factor, does not fully account for the rapid, full, and durable remission of type 2 diabetes, return of islet function, reduction of the prevalence of cancers, increase in gray matter of the brain, and decrease in all-cause mortality. This review supports the thesis that the metabolic syndrome is not a group of separate diseases but rather multiple expressions of a shared defect in the utilization of carbohydrates and lipids. That error is probably caused by a dysmetabolic signal from the foregut, stimulated by food, that limits entry of 2-carbon fragments into the tricarboxylic acid cycle, the accumulation of lactate and, in turn, increases in glucose and insulin. Surgery limits that signal by reducing contact between food and foregut mucosa. Speciation of that signal(s) may offer a new pathway for drug development.

Primary laparoscopic sleeve gastrectomy versus gastric bypass: a propensity-matched comparison of 30-day outcomes

BACKGROUND

Bariatric surgery is the most effective treatment for obesity. There is uncertainty regarding rates of adverse outcomes between the most common methods: laparoscopic Roux-en-Y gastric bypass (LRYGB) and laparoscopic sleeve gastrectomy (LSG).

OBJECTIVES

To compare rates of readmission, reoperation, intervention, unplanned intensive care unit (ICU) admission, all-cause and procedure-related mortality, and postoperative complications at 30 days between LRYGB and LSG.

SETTING

Retrospective, observational, multicenter registry.

METHODS

We identified 611,619 patients from the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP) data registry between January 1, 2015, and December 31, 2018 (447,326 [73.1%] LSG; 164,293 [26.9%] LRYGB).

RESULTS

Adverse events were more common after LRYGB (readmission: 3% with LSG versus 5.9% with LRYGB [P < .001; odds ratio {OR}, LSG/LRYGB = .489]; intervention: .9% with LSG versus 2.4% with LRYGB [P < .001; OR, LSG/LRYGB = .357]; reoperation: .8% with LSG versus 2.3% with LRYGB [P < .001; OR, LSG/LRYGB = .363]; unplanned ICU admission: .52% with LSG versus 1.1% with LRYGB [P < .001; OR, LSG/LRYGB = .454]; all-cause mortality: .07% with LSG versus .15% with LRYGB [P < .001; OR, LSG/LRYGB = .489]; procedure-related mortality: .04% with LSG versus .08% with LRYGB [P < .001; OR, LSG/LRYGB = .446]; Clavien-Dindo I: .20% with LSG versus .63% with LRYGB [P < .001; OR, LSG/LRYGB = .317]; Clavien-Dindo II: .70% with LSG versus 1.3% with LRYGB [P < .001; OR, LSG/LRYGB = .527]; Clavien-Dindo III: 3.3% with LSG versus 6.6% with LRYGB [P < .001; OR, LSG/LRYGB = .481]; Clavien-Dindo IV: .36% with LSG versus .76% with LRYGB [P < .001; OR, LSG/LRYGB = .466]; and Clavien-Dindo V: .07% with LSG versus .15% with LRYGB [P < .001; OR, LSG/LRYGB = .488]). Surgery type was among the strongest independent predictors of adverse events, and LRYGB conferred higher adjusted odds of all adverse outcomes (all-cause mortality: OR, LRYGB/LSG = 1.791 [P < .001]; procedure-related mortality: OR, LRYGB/LSG = 1.979 [P < .001]; readmission: OR, LRYGB/LSG = 1.921 [P < .001]; unplanned ICU admission: OR, LRYGB/LSG = 1.870 [P < .001]; intervention: OR, LRYGB/LSG = 2.662 [P < .001]; reoperation: OR, LRYGB/LSG = 2.646 [P < .001]; and Clavien-Dindo grade: OR, LRYGB/LSG = 2.007 [P < .001]).

CONCLUSION

The rates of 30-day adverse outcomes are lower after LSG compared with after LRYGB. LRYGB independently conferred increased odds of adverse outcomes compared with LSG, and surgery type was among the strongest predictors of adverse outcomes.

Circulating magnesium status is associated with type 2 diabetes remission after Roux-en-Y gastric bypass surgery: a long-term cohort study

BACKGROUND

Low serum magnesium levels predict cardiovascular and all-cause mortality in patients with typ 2 diabetes.

SETTING

Outpatient clinic of obesity and central hospital.

OBJECTIVES

To assess long-term alterations in circulating magnesium status after Roux-en-Y gastric bypass (RYGB) surgery and associations with remission of type 2 diabetes (T2D).

METHODS

Retrospective analysis of 5-year outcomes of plasma magnesium (p-Mg) and glucometabolic statuses in patients who underwent primary RYGB and who completed the annual follow-up program. Data were investigated from 84 patients without diabetes and 62 with T2D before RYGB, who showed either prolonged remission (n = 30), temporary remission (n = 16), or no remission (n = 16) after surgery.

RESULTS

Body mass indexes before RYGB were similar in patients with and without T2D, irrespective of remission. The patients not achieving remission showed longer diabetes durations; higher circulating glucose levels; more intensive antidiabetic drug treatment, including insulin; and significantly lower p-Mg concentrations (.73 [±.08] mmol/L compared with .80-.82 [±.07] mmol/L, respectively; P < .01) than the groups showing remission or without diabetes before surgery. After RYGB, the p-Mg increased similarly, by 10-12% in the groups with T2D before surgery, irrespective of remission; however, the nonremission group did not reach the p-Mg levels registered in the other groups after follow-up. The nonremission group reached .82 (.09) mmol/L, compared with .87 (.06) and .88 (.08) mmol/L (P < .05), respectively, in patients with remission or without a history of diabetes.

CONCLUSION

The p-Mg concentrations increased after RYGB, with similar increments irrespective of T2D remission; however, the nonremission group started from an inferior level and did not reach the p-Mg concentrations seen in the groups achieving remission or without a history of diabetes before surgery.

Defining remission of type 2 diabetes in research studies: A systematic scoping review

BACKGROUND

Remission has been identified as a top priority by people with type 2 diabetes. Remission is commonly used as an outcome in research studies; however, a widely accepted definition of remission of type 2 diabetes is lacking. A report on defining remission was published (but not formally endorsed) in Diabetes Care, an American Diabetes Association (ADA) journal. This Diabetes Care report remains widely used. It was the first to suggest 3 components necessary to define the presence of remission: (1) absence of glucose-lowering therapy (GLT); (2) normoglycaemia; and (3) for duration ≥1 year. Our aim is to systematically review how remission of type 2 diabetes has been defined by observational and interventional studies since publication of the 2009 report.

METHODS AND FINDINGS

Four databases (MEDLINE, EMBASE, Cochrane Library, and CINAHL) were searched for studies published from 1 September 2009 to 18 July 2020 involving at least 100 participants with type 2 diabetes in their remission analysis, which examined an outcome of type 2 diabetes remission in adults ≥18 years and which had been published in English since 2009. Remission definitions were extracted and categorised by glucose-lowering therapy, glycaemic thresholds, and duration. A total of 8,966 titles/abstracts were screened, and 178 studies (165 observational and 13 interventional) from 33 countries were included. These contributed 266 definitions, of which 96 were unique. The 2009 report was referenced in 121 (45%) definitions. In total, 247 (93%) definitions required the absence of GLT, and 232 (87%) definitions specified numeric glycaemic thresholds. The most frequently used threshold was HbA1c<42 mmol/mol (6.0%) in 47 (20%) definitions. Time was frequently omitted. In this study, a total of 104 (39%) definitions defined time as a duration. The main limitations of this systematic review lie in the restriction to published studies written in English with sample sizes of over 100. Grey literature was not included in the search.

CONCLUSIONS

We found that there is substantial heterogeneity in the definition of type 2 diabetes remission in research studies published since 2009, at least partly reflecting ambiguity in the 2009 report. This complicates interpretation of previous research on remission of type 2 diabetes and the implications for people with type 2 diabetes. Any new consensus definition of remission should include unambiguous glycaemic thresholds and emphasise duration. Until an international consensus is reached, studies describing remission should clearly define all 3 components of remission.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42019144619.

Adipose depot-specific upregulation of Ucp1 or mitochondrial oxidative complex proteins are early consequences of genetic insulin reduction in mice

Hyperinsulinemia plays a causal role in adipose tissue expansion. Mice with reduced insulin have increased energy expenditure, but the mechanisms remained unclear. Here we investigated the effects of genetically reducing insulin production on uncoupling and oxidative mitochondrial proteins in liver, skeletal muscle, white adipose tissue (WAT), and brown adipose tissue (BAT). Male Ins1^+/+ or Ins1^+/- littermates were fed either a low-fat diet (LFD) or a high-fat diet (HFD) for 4 wk, starting at 8 wk of age. Replicating our previous observations, HFD increased fasting hyperinsulinemia, and Ins1^+/- mice had significantly lower circulating insulin compared with Ins1^+/+ littermates. Fasting glucose and body weight were not different between genotypes. We did not observe robust significant differences in liver or skeletal muscle. In mesenteric WAT, Ins1^+/- mice had reduced Ndufb8 and Sdhb, while Ucp1 was increased in the context of HFD. HFD alone had a dramatic inhibitory effect on Pparg abundance. In inguinal WAT, Ins1^+/- mice exhibited significant increases in oxidative complex proteins, independent of diet, without affecting Ucp1, Pparg, or Prdm16:Pparg association. In BAT, lowered insulin increased Sdhb protein levels that had been reduced by HFD. Ucp1 protein, Prdm16:Pparg association, and Sirt3 abundance were all increased in the absence of diet-induced hyperinsulinemia. Our data show that reducing insulin upregulates oxidative proteins in inguinal WAT without affecting Ucp1, whereas in mesenteric WAT and BAT, reducing insulin upregulates Ucp1 in the context of HFD. Preventing hyperinsulinemia has early depot-specific effects on adipose tissue metabolism and helps explain the increased energy expenditure previously reported in Ins1^+/- mice.

Does Reconstruction Type After Gastric Resection Matters for Type 2 Diabetes Improvement?

BACKGROUND

Gastrointestinal (GI) surgery involving gastric resection and bypass of intestinal segments was reported to facilitate glucose control in obese patients with type 2 diabetes (T2D).

AIM

Our aim was to assess whether the type of post-gastrectomy GI reconstruction also influences glucose control in T2D patients with BMI below 35 kg/m² submitted to gastrointestinal surgery without bariatric intention.

METHODS

A cohort of T2D Caucasian patients (n = 40) with upper GI malignancy (n = 33) or complicated reflux disease (n = 7) were submitted to either a gastrectomy plus Billroth II (BII) gastrojejunal anastomosis (n = 17), a gastrectomy plus Roux-en-Y gastrojejunostomy (RY) reconstruction (n = 18; subtotal gastrectomy n = 7 and total gastrectomy n = 11), or atypical gastrectomy without reconstruction (no-R) (n = 5). Patients were evaluated before and 2 years after surgery for body weight, Hb1Ac, need of glucose lowering drugs, and presence of diabetes.

RESULTS

Body mass index (BMI) decreased after every surgical procedure when compared to baseline (- 0.9 ± 0.8 kg/m² for BII vs - 4.3 ± 2.6 kg/m² for RY vs - 4.6 ± 2.5 kg/m² for no-R, p < 0.05), which was only significantly different after RY surgeries. Diabetes remission occurred in 5.9% of BII patients, in 27.8% of RY patients, and 0% of no-R patients, while in patients with persistent T2D, the needs for glucose-lowering drugs were significantly also decreased after RY (31.3% BII vs 66.7% RY vs 25% no-R, p = 0.03).

CONCLUSIONS

T2D Caucasian patients undergoing post-gastrectomy GI reconstructions without a bariatric intention experience a significant improvement of T2D, in a magnitude that could be influenced by the technical procedure performed in favor of RY reconstruction. Thus, presence of T2D should be taken into consideration when deciding for the type of post-gastrectomy GI reconstruction.

Midterm Outcomes of Gastric Pouch Resizing for Weight Regain After Roux-en-Y Gastric Bypass

PURPOSE

Resizing of the gastric pouch, with eventually resizing of the gastrojejunal anastomosis, has been proposed as revisional procedure to treat weight regain after Roux-en-Y gastric bypass (RYGB), in patients with large gastric pouch and/or large gastrojejunal (GJ) anastomosis. The aim of this study is to determine the midterm results and the safety of laparoscopic resizing of the gastric pouch after RYGB in cases where gastric pouch is > 200 ml and/or GJ anastomosis > 20 mm.

MATERIALS AND METHODS

All patients who underwent gastric pouch resizing between January 2009 and December 2016 were retrospectively reviewed from a prospective database. The gastric pouch was resized to a volume of 30-40 ml.

RESULTS

A total of 48 patients had gastric pouch resizing after RYGB. The mean initial BMI was 42.9 ± 4.8 kg/m². Perioperative morbidity was 8.3% in this series. Mean follow-up was 5.4 years. The mean BMI was 30.0 ± 7.3 kg/m² at 1 year, 30.0 ± 6.0 kg/m² at 3 years, and 30.9 ± 5.7 kg/m² at 5 years. Mean %EBMIL at 1-, 3-, and 5-year follow-up was 51.9%, 55.1%, and 39%, respectively, in 48% follow-up rate. The obesity-related comorbidities disappeared in 67.3% of cases at maximum follow-up.

CONCLUSIONS

In carefully selected patients with gastric pouch size > 200 ml and/or GJ anastomosis > 20 mm, and after extensive preoperative evaluation, gastric pouch resizing is a potentially effective option to treat weight regain due to anatomical factors after RYGB, with complication rate of 8%.

The immune remodel: Weight loss-mediated inflammatory changes to obesity

Obesity is an escalating world problem that contributes to the complexity and cost of treatment of metabolic disorders. Obesity is the result of increased storage of energy in the form of adipose tissue, reducing the quality of daily life, and interfering with longevity. Obesity is also a chronic, low-grade inflammatory disorder. The inflammatory processes affect many organ systems with expanded numbers of immune cells and increased cytokine production. Long-term weight loss is difficult to achieve and maintain. Lifestyle modifications, pharmacologic treatments, and surgical methods are increasingly utilized to ameliorate excess body weight and the comorbidities of obesity, such as diabetes, cardiovascular disease, dyslipidemia, and cancers. Weight loss is also touted to reduce inflammation. Here we review the current literature on human obesity-related systemic and local changes to the immune system and circulating inflammatory mediators. Further, we consider the impact of weight loss to reduce the burden of inflammation, bearing in mind the different methods of weight loss—behavioral change vs. surgical intervention.

Hypothesis: Role of Reduced Hepatic Insulin Clearance in the Pathogenesis of Type 2 Diabetes

There is wide variance among individuals in the fraction of insulin cleared by the liver (20% to 80%). Hepatic insulin clearance is 67% lower in African Americans than European Americans. Clearance is also lower in African American children 7-13 years of age. Lower hepatic insulin clearance will result in peripheral hyperinsulinemia: this exacerbates insulin resistance, which stresses the β-cells, possibly resulting in their ultimate failure and onset of type 2 diabetes. We hypothesize that lower insulin clearance can be a primary cause of type 2 diabetes in at-risk individuals.

Plasma lactate as a marker of metabolic health: Implications of elevated lactate for impairment of aerobic metabolism in the metabolic syndrome

BACKGROUND

Fasting lactate is elevated in metabolic diseases and could possibly be predictive of the risk of developing the metabolic syndrome.

METHODS

Plasma samples were analyzed for fasting lactate to compare lean subjects, nondiabetic subjects with severe obesity, and metabolically impaired subjects. Subjects with severe obesity were studied 1 week before and 1 week to 9 months after gastric bypass surgery. Subjects with components of the metabolic syndrome were studied before and after 6 months of an exercise intervention.

RESULTS

Metabolically impaired subjects had higher fasting lactate concentrations (P < .0001) and respond to a glucose or insulin challenge with higher lactates than non-obese subjects (P < .004). Lactate was significantly reduced a week after gastric bypass surgery (P < .05) and further reduced 1 to 9 months after surgery (0.95 ± 0.04 mM in non-obese, 1.26 ± 0.12 mM in subjects with severe obesity, and 0.68 ± 0.03 mM 1-3 months after gastric bypass). Six months of chronic exercise resulted in a 16% reduction (P = .028) in fasting lactate.

CONCLUSION

Fasting plasma lactate was elevated in obese subjects with the metabolic syndrome compared with healthy lean individuals. Lactate was reduced by exercise and bariatric surgery, interventions that improve metabolic health and risk for subsequent disease. The results of this study and those previously published by our research group suggest that elevated lactate may be caused by an impairment in aerobic metabolism and may offer a metric assessing the severity of the metabolic syndrome.

Comparison of early type 2 diabetes improvement after gastric bypass and sleeve gastrectomy: medication cessation at discharge predicts 1-year outcomes

BACKGROUND

Although weight loss-dependent type 2 diabetes (T2D) improvement after sleeve gastrectomy (SG) is well documented, whether SG has a weight-independent impact on T2D is less studied.

OBJECTIVES

To evaluate early, weight-independent T2D improvement after SG and Roux-en-Y gastric bypass (RYGB) and its relationship to longer-term T2D outcomes.

SETTING

University Hospital, United States.

METHODS

We completed a retrospective cohort study of patients with T2D who underwent SG (n = 187) or RYGB (n = 246) from 2010 to 2015. Pre- and postoperative parameters, including demographic characteristics, T2D characteristics, and T2D medication requirements, blood glucose, glycosylated hemoglobin, weight, and body mass index, were reviewed.

RESULTS

T2D improved within days after both SG and RYGB, with more patients off T2D medications after SG than RYGB (39% versus 25%, respectively; P < .01) at the time of discharge (2.5 ± .8 versus 2.7 ± 1 d; P = .04). Over the initial postoperative 12 months, T2D medication cessation rates remained relatively stable after SG but continued to improve after RYGB (at 12 mo: 52% versus 68%, respectively; P < .05). T2D medication cessation at discharge predicts 12-month T2D medication cessation (92% [RYGB] and 78% [SG] positive predictive value). In a mixed-effects regression model adjusting for weight loss and severity of diabetes, discharge T2D medication cessation remained a significant predictor of T2D outcomes after both RYGB (odds ratio, 51; 95% confidence interval, 16.1-161; P < .0001) and SG (6.4; 95% confidence interval, 2.8-14.7; P < .0001).

CONCLUSIONS

Both SG and RYGB lead to high rates of T2D medication cessation within days of surgery, suggesting both operations activate weight loss-independent anti-T2D pathways. T2D medication cessation at discharge is predictive of 12-month T2D outcomes, particularly in noninsulin requiring patients. By 1 year after the surgery, RYGB leads to more weight loss and higher rates of T2D medication cessation than SG.

Can type 2 diabetes be reversed and how can this best be achieved? James Lind Alliance research priority number one

The James Lind Alliance, in association with Diabetes UK, conducted a survey of people with Type 2 diabetes to establish their priorities for research. The number one research priority was found to be 'Can Type 2 diabetes be cured or reversed, what is the best way to achieve this, and is there a point beyond which the condition cannot be reversed?'. The present review summarizes the current understanding of weight loss-induced reversal of Type 2 diabetes. It considers the diagnostic criteria for remission and describes the clinical features of post-diabetes. It is of great importance to recognize these, as post-diabetes differs considerably from the high cardiovascular risk state of prediabetes. Current data demonstrate long-term stable β-cell function, providing weight regain is prevented. If an individual, having previously demonstrated susceptibility to Type 2 diabetes, returns to their previous weight then recurrence of the condition is certain. Appropriate use of the terms 'reversal' and 'remission' is discussed, with emphasis that the word 'cure' is inappropriate. Evidence-based means of achieving and maintaining remission of Type 2 diabetes are described, together with a summary of the information on the steadily diminishing chance of achieving reversal with increasing duration of Type 2 diabetes.

Prospective evaluation of insulin and incretin dynamics in obese adults with and without diabetes for 2 years after Roux-en-Y gastric bypass

AIMS/HYPOTHESIS

In this prospective case-control study we tested the hypothesis that, while long-term improvements in insulin sensitivity (S_I) accompanying weight loss after Roux-en-Y gastric bypass (RYGB) would be similar in obese individuals with and without type 2 diabetes mellitus, stimulated-islet-cell insulin responses would differ, increasing (recovering) in those with diabetes but decreasing in those without. We investigated whether these changes would occur in conjunction with favourable alterations in meal-related gut hormone secretion and insulin processing.

METHODS

Forty participants with type 2 diabetes and 22 participants without diabetes from the Longitudinal Assessment of Bariatric Surgery (LABS-2) study were enrolled in a separate, longitudinal cohort (LABS-3 Diabetes) to examine the mechanisms of postsurgical diabetes improvement. Study procedures included measures of S_I, islet secretory response and gastrointestinal hormone secretion after both intravenous glucose (frequently-sampled IVGTT [FSIVGTT]) and a mixed meal (MM) prior to and up to 24 months after RYGB.

RESULTS

Postoperatively, weight loss and S_I-_FSIVGTT improvement was similar in both groups, whereas the acute insulin response to glucose (AIRglu) decreased in the non-diabetic participants and increased in the participants with type 2 diabetes. The resulting disposition indices (DI_FSIVGTT) increased by three- to ninefold in both groups. In contrast, during the MM, total insulin responsiveness did not significantly change in either group despite durable increases of up to eightfold in postprandial glucagon-like peptide 1 levels, and S_I-MM and DI_MM increased only in the diabetes group. Peak postprandial glucagon levels increased in both groups.

CONCLUSIONS/INTERPRETATION

For up to 2 years following RYGB, obese participants without diabetes showed improvements in DI that approach population norms. Those with type 2 diabetes recovered islet-cell insulin secretion response yet continued to manifest abnormal insulin processing, with DI values that remained well below population norms. These data suggest that, rather than waiting for lifestyle or medical failure, RYGB is ideally considered before, or as soon as possible after, onset of type 2 diabetes.

TRIAL REGISTRATION

ClinicalTrials.gov NCT00433810.

Increased circulating magnesium concentrations after Roux-en-Y gastric bypass surgery in patients with type 2 diabetes

BACKGROUND

Low circulating magnesium concentrations predict cardiovascular and all-cause mortality in patients with type 2 diabetes (T2D). Epidemiologic and clinical studies have indicated lower extra- and intracellular magnesium concentrations in patients with diabetes.

OBJECTIVE

We aimed to describe alterations, if any, in circulating magnesium concentrations after laparoscopic Roux-en-Y gastric bypass surgery (LRYGB) in patients with obesity and T2D.

SETTING

Outpatient clinic of obesity and central hospital.

METHODS

Retrospective analysis of 1-year outcome of plasma magnesium (p-Mg) and glucometabolic status in all consecutive patients who underwent primary LRYGBP and who completed the follow-up visits, including biochemical test panels 6 and 12 months after surgery.

RESULTS

LRYGBP and complete follow-up visits were performed in 51 patients with T2D and 86 patients without T2D. All patients were given similar dietary advice and multivitamin and mineral supplementation after surgery. Before RYGB, the patients with T2D showed lower p-Mg compared with patients without T2D (.79 ± .06 mM and .82 ± .05 mM, respectively, P<.01). P-Mg was inversely correlated to fasting blood glucose and glycosylated hemoglobin levels. After surgery, mean p-Mg increased by 5.2% in the group with T2D compared with 1.4% in the patients without T2D (P<.01), ending at an equal level of .83 mM. The alterations in p-Mg were inversely related to the changes in fasting glucose and glycosylated hemoglobin concentrations.

CONCLUSION

The lowered p-Mg associated with impaired glucometabolic status in patients with T2D was increased after LRYGBP, reaching similar concentrations as in patients without T2D.

Relationship Between Vitamin D Deficiency and the Components of Metabolic Syndrome in Patients with Morbid Obesity, Before and 1 Year After Laparoscopic Roux-en-Y Gastric Bypass or Sleeve Gastrectomy

BACKGROUND

Vitamin D deficiency (VDD) is associated with obesity and metabolic syndrome (MS). After bariatric surgery (BS), high rates of VDD often persist and some patients are refractory to the resolution of comorbidities. The aim of the present study is to analyse the relationship between the levels of vitamin D and the persistence of MS components at 12 months after BS, according to the surgical technique used.

METHODS

We performed a retrospective study of 46 patients undergoing BS: 23 underwent laparoscopic Roux-en-Y gastric bypass (LRYGBP) and 23 laparoscopic sleeve gastrectomy (LSG). These patients had an average BMI of 45 kg/m² (34-63). Levels of vitamin D were classified as deficient (<20 ng/dl), insufficient (20-30 ng/dl) or normal (>30 ng/dl) and analysed in relation to the components of MS (high blood pressure (HBP), dyslipidaemia (DL) and type 2 diabetes mellitus (T2DM) preoperatively and 12 months after surgery.

RESULTS

VDD was observed in 77% of the patients prior to surgery. There were no significant associations between predisposing factors and baseline vitamin D. After surgery, plasma levels of vitamin D increased in both groups, but only 18% of the patients achieved normal values. Both groups had achieved significant improvements in MS components. Thus, 63% of all the patients achieved complete resolution of HBP, 54% that of DL and 77% that of T2DM. Moreover, MS was present in 11% of the patients, compared to 63% at baseline, and the MS resolution rate was 83%, with no significant differences between LRYGBP and LSG.

CONCLUSIONS

There is a relationship between VDD and persistence of MS, and particularly so with T2DM. VDD could represent a predictor of MS persistence at 12 months after surgery.

Epigenetic programming, early life nutrition and the risk of metabolic disease

Time separates the past from the present, during this period memory are formed - written in code and decoded to be read while other memories are erased - but when it comes to the epigenome some memories are harder to forget than others. Recent studies show chemical information is written in the context of the epigenome and codified on histone and non-histone proteins to regulate nuclear processes such as gene transcription. The genome is also subject to modification in the form of 5-methylcytosine, which has been implicated in metabolic memory. In this review, we examine some of the chemical modifications that signal early life events and explore epigenetic changes that underlie the diabetic vasculature. The fine balance between past and present is discussed, as it pertains to gestational diabetes and obesity in context to the Barker hypothesis. We also examine emerging experimental evidence suggesting the hypothalamus as a central regulator of obesity risk and explore current genomic medicine. As for how cells recall specific chemical information, we examine the experimental evidence implicating chemical cues on the epigenome, providing examples of diet during pregnancy and the increased risk of disease in offspring.

Evidence Base for Optimal Preoperative Preparation for Bariatric Surgery: Does Mandatory Weight Loss Make a Difference?

PURPOSE OF REVIEW

Preoperative weight loss regimens prior to bariatric surgery have been a routine and common practice for many centers, in the US and around the world. The mandated participation in such programs has largely been influenced by loco-regional payer requirements. The relationship between adherence to a mandatory weight loss regimen and achieved preoperative weight loss as well as the clinical impact of preoperative weight loss on bariatric outcomes remains uncertain.

RECENT FINDINGS

This review examines the available current literature, in the context of previous findings, regarding the impact of mandated preoperative weight loss regimens and mandatory weight loss on bariatric outcomes. The reviewed studies do not provide sufficient evidence that mandatory participation in a preoperative weight loss regimen prior to bariatric surgery is associated with achieved weight loss or durable bariatric outcome benefit. Preoperative weight loss, when achieved, may confer a positive benefit on postoperative complications; however, this is not a consistent finding in the literature and requires further validation. The practice of mandating participation in a preoperative weight loss regimen or requiring mandatory weight loss prior to bariatric surgery is not supported by current literature and may serve as an obstacle to medically necessary and potentially life-saving treatment.

LONG-TERM BONE HEALTH AFTER ROUX-EN-Y GASTRIC BYPASS: A PILOT STUDY

OBJECTIVE

This cross-sectional study was undertaken to assess metabolic bone disease by examining bone mineral density (BMD), fracture prevalence, and nutritional factors pertinent to bone in a cohort >9 years post-Rouxen-Y gastric bypass (RYGB).

METHODS

Fifty-one subjects 9.4 to 36.0 years (mean 17.0 ± 8.1) post-RYGB provided a focused history. Dietary calcium and protein were assessed. Dual-energy X-ray absorptiometry (DXA) BMD at the spine, hip, and radius and routine serum chemistries, magnesium, phosphorus, parathyroid hormone, vitamin D, vitamin K, and micronutrients were analyzed. Sixteen subjects provided 24-hour urine for measurement of calcium.

RESULTS

The mean maximum weight loss was 70.3 ± 20 kg (47.4 ± 8.9%), and mean net weight loss was 46.9 ± 23.1 kg (31.2 ± 12.5%). The prevalence rates of fracture, secondary hyperparathyroidism, and vitamin D deficiency were 15.7%, 37%, and 39%, respectively. BMD was in the osteoporotic range in 27.5%. The mean calcium:creatinine clearance ratio was 0.0124 ± 0.0131. Median intakes of dietary calcium, total calcium, protein, and vitamin D were 582.5 mg, 947.5 mg, 50.2 g, and 1,000 IU, respectively. Mean Z-scores at all sites were <0 (P<.01). A negative correlation (P<.05) was noted between distal radius Z-score and net change in BMI. Net change in BMI was greater for those with osteoporosis than those without. (P<.05) Conclusion: Many years after RYGB, BMD remains lower than expected compared to an age-, sex-, race-, and weight-matched reference population and is correlated with the amount of weight lost. Deficiencies of Vitamin D and calcium are prevalent.

ABBREVIATIONS

BMD = bone mineral density BMI = body mass index Ca:Cr = calcium:creatinine DXA = dual-energy X-ray absorptiometry PTH = parathyroid hormone RYGB = Roux-en-Y gastric bypass UD = ultradistal WHO = World Health Organization.

Metabolic syndrome and the hepatorenal reflex

Insufficient hepatic O₂ in animal and human studies has been shown to elicit a hepatorenal reflex in response to increased hepatic adenosine, resulting in the stimulation of renal as well as muscle sympathetic nerve activity and activating the renin angiotensin system. Low hepatic ATP, hyperuricemia, and hepatic lipid accumulation reported in metabolic syndrome (MetS) patients may reflect insufficient hepatic O₂ delivery, potentially accounting for the sympathetic overdrive associated with MetS. This theoretical concept is supported by experimental results in animals fed a high fructose diet to induce MetS. Hepatic fructose metabolism rapidly consumes ATP resulting in increased adenosine production and hyperuricemia as well as elevated renin release and sympathetic activity. This review makes the case for the hepatorenal reflex causing sympathetic overdrive and metabolic syndrome in response to exaggerated splanchnic oxygen consumption from excessive eating. This is strongly reinforced by the fact that MetS is cured in a matter of days in a significant percentage of patients by diet, bariatric surgery, or endoluminal sleeve, all of which would decrease splanchnic oxygen demand by limiting nutrient contact with the mucosa and reducing the nutrient load due to loss of appetite or dietary restriction.

Calorie restriction and reversal of type 2 diabetes

Type 2 diabetes causes major global health problems and has been believed to be a lifelong condition with inevitable worsening. Steadily increasing numbers of drugs appeared to be required to achieve even modest control. Early type 2 diabetes has now been shown to be reversed by substantial weight loss and this has allowed temporal tracking of the underlying pathophysiological changes. Areas covered: In early type 2 diabetes, negative calorie balance decreases liver fat within days, and allows return of normal control of hepatic glucose production. Over 8 weeks, the negative calorie balance allows the raised levels of intra-pancreatic fat and simultaneously first phase insulin secretion to normalise. These findings are consistent with the 2008 Twin Cycle Hypothesis of the etiology and pathogenesis of type 2 diabetes. Individuals develop type 2 diabetes when they exceed their personal fat threshold for safe storage of fat and there is no difference in pathophysiology between those with BMI above or below 30 kg/m². Expert commentary: Type 2 diabetes can now be understood as a state of excess fat in liver and pancreas, and remains reversible for at least 10 years in most individuals.

A comparison of outcomes of bariatric surgery in patient greater than 70 with 18 month of follow up

BACKGROUND

There is a scarcity of data available to determine the safety and effectiveness of bariatric surgery in the elderly population. Additionally, there are no studies showing the effect of the single anastomosis duodenal switch (SADS) has on the elderly obese, in comparison with other more popular procedures. Here we compare laparoscopic gastric band surgery (LAGB), Laparoscopic Roux-en-Y gastric bypass surgery (LRYGB), and the SADS to analyze the weight loss, perioperative and postoperative morbidity in the patients >70 years of age at a single US center.

METHODS

A retrospective analysis was performed on 53 consecutive patients ≥70 years old who underwent weight loss surgery from 2009 to 2015.Weight loss in terms of the percentage excess body mass index lost (%EBMIL), percentage excess weight lost (%EWL) and body mass index (BMI) points lost, resolution of comorbidities, length of stay, early (30-day) and late complication rates were compared using descriptive statistics and non-linear regression analysis.

RESULTS

Of 53 patients, 24 underwent LAGB, 14 underwent LRYGB and 15 underwent SADS. The average patient age was 72.7 ± 2.5 years (range, 70-81.4) and 66 % were females. There was no statistical difference in the demographic data between three groups except for age and sleep apnea. There were no operative or early deaths. There were differences in complication rates between the surgical arms; however, with our small data set statistical significance was not achieved. There was 1 patient who lost to follow up in SADS group. Follow up time period was 18 months.  % EBMIL and BMI reduction showed a statistically significant difference between the procedures, where the SADS had the highest loss of  %EBMIL and BMI points. Comorbidities prevalence decreased post-operatively with SADS having higher percentage of patients who had resolution of their comorbidities.

CONCLUSION

Each of the three procedures can be performed on patients older than 70 with low morbidity rate. However, when the focus is weight loss alone, the SADS procedure is the most effective of the three procedures in regards to weight loss in the short term for patients older than 70. The SADS is as safe as RYGB but LAGB with all its limitations is still the safest bariatric procedure.

Metabolic syndrome and the hepatorenal reflex

Insufficient hepatic O₂ in animal and human studies has been shown to elicit a hepatorenal reflex in response to increased hepatic adenosine, resulting in stimulation of renal as well as muscle sympathetic nerve activity and activating the renin angiotensin system. Low hepatic ATP, hyperuricemia, and hepatic lipid accumulation reported in metabolic syndrome (MetS) patients may reflect insufficient hepatic O₂ delivery, potentially accounting for the sympathetic overdrive associated with MetS. This theoretical concept is supported by experimental results in animals fed a high fructose diet to induce MetS. Hepatic fructose metabolism rapidly consumes ATP resulting in increased adenosine production and hyperuricemia as well as elevated renin release and sympathetic activity. This review makes the case for the hepatorenal reflex causing sympathetic overdrive and metabolic syndrome in response to exaggerated splanchnic oxygen consumption from excessive eating. This is strongly reinforced by the fact that MetS is cured in a matter of days in a significant percentage of patients by diet, bariatric surgery, or endoluminal sleeve, all of which would decrease splanchnic oxygen demand by limiting nutrient contact with the mucosa and reducing the nutrient load due to the loss of appetite or dietary restriction.

The role of bariatric surgery in the management of nonalcoholic fatty liver disease and metabolic syndrome

Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease worldwide. NAFLD is strongly associated with obesity and metabolic syndrome (MetS). Current treatment of NAFLD is based on weight reduction. Bariatric surgery is the most effective treatment for morbid obesity and its associated metabolic comorbidities. There is evidence indicating that bariatric surgery improves histological and biochemical parameters of NAFLD, but currently is not considered a treatment option for NAFLD. The aim of this work is to review the evidence for the effects of bariatric surgery on NAFLD and the MetS. We found that insulin resistance, alterations in glucose metabolism, hypertension, plasma lipids, transaminases, liver steatosis, steatohepatitis and fibrosis improve after bariatric surgery. Weight loss and improvement of NAFLD are greater after RYGB than after other interventions. These findings were obtained from retrospective or cohort studies. There are no studies designed to evaluate liver-specific mortality, liver transplantation, or quality of life. Patients with indications for bariatric surgery will benefit from the improvements in the MetS and NAFLD.

Clinical Outcomes of Metabolic Surgery: Microvascular and Macrovascular Complications

Understanding of the long-term clinical outcomes associated with bariatric surgery has recently been advanced. Research related to the sequelae of diabetes-in particular, long-term microvascular and macrovascular complications-in patients who undergo weight-loss surgery is imperative to this pursuit. While numerous randomized control trials have assessed glucose control with bariatric surgery compared with intensive medical therapy, bariatric surgery outcome data relating to microvascular and macrovascular complications have been limited to observational studies and nonrandomized clinical trials. As a result, whether bariatric surgery is associated with a long-term reduction in microvascular and macrovascular complications when compared with current intensive glycemic control therapy cannot be determined because the evidence is insufficient. However, the consistent salutary effects of bariatric surgery on diabetes remission and glycemic improvement support the opportunity (and need) to conduct high-quality studies of bariatric surgery versus intensive glucose control. This review provides relevant background information related to the treatment of diabetes, hyperglycemia, and long-term complications; reports clinical findings (to date) with bariatric surgery; and identifies ongoing research focusing on long-term vascular outcomes associated with bariatric surgery.

Longer-Term Physiological and Metabolic Effects of Gastric Bypass Surgery

Obesity is closely associated with the development of type 2 diabetes. Many strategies have been used in the past to combat these two conditions, but very few provide for stable and durable glycemic control. Bariatric surgery has emerged as a powerful tool for treating obesity and in over 70 % of cases provides a short-term cure for diabetes. While the acute metabolic effects of surgery are striking, it remains important for us to also consider the long-term effects. This review aims to summarize the chronic or long-term metabolic and physiological effects of Roux-en-Y gastric bypass (RYGB) surgery on pancreatic function, skeletal muscle and hepatic insulin sensitivity, and gastrointestinal remodeling. An increased understanding of the current state of research in these areas can provide the basis for stimulating further research that would contribute to new treatment and management strategies for obesity and diabetes.

Consequences of bariatric surgery on oesophageal function in health and disease

Obesity is a continuing epidemic with substantial associated morbidity and mortality. Owing to the limitations of lifestyle modifications and pharmacological options, bariatric surgery has come to the forefront as an efficient method of achieving sustained weight loss and decreasing overall mortality in comparison with nonsurgical interventions. The most frequently performed bariatric operations are either purely restrictive, such as laparoscopic adjustable gastric band (LAGB) and laparoscopic sleeve gastrectomy (LSG), or restrictive-malabsorptive, such as the Roux-en-Y gastric bypass (RYGB). Each operation results in weight loss, but can also have unintended effects on the health of the oesophagus. Specifically, operations might lead to oesophageal dilation or the development of GERD. LAGB is the best-studied procedure with notable evidence for postoperative worsening of GERD and pseudo-achalasia, which increases lower oesophageal pressure and causes aperistalsis. In some studies, LSG initiates not only a worsening of GERD, but also the formation of de novo GERD in patients without preoperative GERD symptoms. RYGB demonstrates the most profound evidence for improvement of GERD symptoms and preservation of oesophageal motility. Future high-quality studies will be required to better understand the interaction between bariatric surgery and oesophageal disease.

Insulin Sensitivity and β-Cell Function Improve after Gastric Bypass in Severely Obese Adolescents

OBJECTIVE

To test the hypothesis that insulin secretion and insulin sensitivity would be improved in adolescents after Roux-en-Y gastric bypass (RYGB).

STUDY DESIGN

A longitudinal study of 22 adolescents and young adults without diabetes undergoing laparoscopic RYGB (mean age 17.1 ± 1.42 years; range 14.5-20.1; male/female 8/14; Non-Hispanic White/African American 17/5) was conducted. Intravenous glucose tolerance tests were done to obtain insulin sensitivity (insulin sensitivity index), insulin secretion (acute insulin response to glucose ), and the disposition index as primary outcome variables. These variables were compared over the 1 year of observation using linear mixed modeling.

RESULTS

In the 1-year following surgery, body mass index fell by 38% from a mean of 61 ± 12.3 to 39 ± 8.0 kg/m(2) (P < .01). Over the year following surgery, fasting glucose and insulin values declined by 54% and 63%, respectively. Insulin sensitivity index increased 300% (P < .01), acute insulin response to glucose decreased 56% (P < .01), leading to a nearly 2-fold increase in the disposition index (P < .01). Consistent with improved β-cell function, the proinsulin to C-peptide ratio decreased by 21% (P < .01).

CONCLUSIONS

RYGB reduced body mass index and improved both insulin sensitivity and β-cell function in severely obese teens and young adults. These findings demonstrate that RYGB is associated with marked metabolic improvements in obese young people even as significant obesity persists.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT00360373.

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

BACKGROUND AND AIMS

Bariatric surgery results in the remission of type 2 diabetes mellitus (T2DM) in morbidly obese subjects. The aim of the study was to investigate the predictive value of both static and dynamic measures of C-peptide in relation to T2DM resolution 6 months after bariatric surgery regardless of the operation type.

METHODS AND RESULTS

A non-randomized prospective study of 24 participants with T2DM undergoing bariatric surgery. Measurements of fasting and 2-hour plasma glucose, insulin, C-peptide and measures of insulin sensitivity were recorded temporally during an oral glucose tolerance test pre-operatively and 6 months post-operatively. A responder was defined with a fasting glucose <5.6 mmol/L and HbA1c <6.0% postoperatively. Within the sample there were 11 responders and 13 non-responders at 6 months. There was a significant difference in the duration of diabetes between the groups. Fasting C-peptide (P≤0.05) and 2-hour C-peptide (P≤0.05) were higher in responders compared to non-responders. Significantly higher C-peptide levels were observed preoperatively at all time points for responders, with significantly higher area under the curve (AUC0-60 and AUC0-120). Using the lower quartiles for C-peptide levels, both fasting C-peptide (>2.5 ng/mL [0.83 nmol/L]) and 2-hour C-peptide (>5.2 ng/mL [1.73 nmol/L]) had a sensitivity and negative predictive value of 100% to predict T2DM remission. Logistic regression showed that C-peptide, duration of diabetes and BMI were associated with response. The area under the ROC curve was 0.94 and a regression model predicted diabetes remission with a sensitivity of 85.7% and a specificity of 88.9%.

CONCLUSIONS

This study demonstrated that static (fasting) and dynamic (AUC, 2-hour) C-peptide measurements predict T2DM resolution 6 months following bariatric surgery. This work provides insight into C-peptide dynamics as a predictor of response to bariatric surgery.

Amelioration of glycemic control by sleeve gastrectomy and gastric bypass in a lean animal model of type 2 diabetes: restoration of gut hormone profile

BACKGROUND

In obese diabetic patients, bariatric surgery has been shown to induce remission of type 2 diabetes. Along with weight loss itself, changes in gut hormone profiles after surgery play an important role in the amelioration of glycemic control. However, the potential of gastrointestinal surgery regarding diabetes remission in non-severely obese diabetic patients has yet to be defined. In the present experimental study, we explored the effect of established bariatric procedures with and without duodenal exclusion on glycemic control and gut hormone profile in a lean animal model of type 2 diabetes.

METHODS

Forty 12- to 14-week-old non-obese diabetic Goto-Kakizaki (GK) rats were randomly assigned to four groups: control group (GKC), sham surgery (GKSS), sleeve gastrectomy (GKSG), and gastric bypass (GKGB). Age-matched Wistar rats served as a non-diabetic control group (WIC). Glycemic control and plasma lipids were assessed at the beginning of the observation period and 4 weeks after surgery. Fasting and mixed meal-induced plasma levels of ghrelin, glucagon-like peptide-17-36 (GLP-1), and peptide tyrosine-tyrosine (PYY) were measured.

RESULTS

In GK rats, glycemic control improved after sleeve gastrectomy (SG) and gastric bypass (GB). Mixed meal-induced gut hormone profiles in Wistar rats (WIC) were significantly different from those of sham-operated or control group GK rats. After SG and GB, GK rats showed a similar postprandial decrease in ghrelin as observed in non-diabetic WIC. Following both surgical procedures, a significant meal-induced increase in PYY and GLP-1 could be demonstrated.

CONCLUSIONS

SG and GB induce a similar improvement in overall glycemic control in lean diabetic rodents. Meal-induced profiles of ghrelin, GLP-1, and PYY in GK rats are significantly modified by SG and GB and become similar to those of non-diabetic Wistar rats. Our data do not support the hypothesis that duodenal exclusion and early contact of food with the ileal mucosa alone explain changes in gut hormone profile in GK rats after gastrointestinal surgery.

Prevalence of undiagnosed and inadequately treated type 2 diabetes mellitus, hypertension, and dyslipidemia in morbidly obese patients who present for bariatric surgery

BACKGROUND

Pharmacotherapy is considered the primary treatment modality for diabetes mellitus (DM), hypertension (HTN), and dyslipidemia (DYS). We sought to investigate the status of DM, HTN, and DYS in patients who seek bariatric surgery.

METHODS

Demographic and comorbidity history were prospectively collected on 1,508 patients referred for bariatric consultation at a single institution from February 2008 to March 2012. We utilized published consensus guidelines (GL) to benchmark the efficacy of standard pharmacotherapy for these metabolic diseases, and 881 patients met the study design criteria.

RESULTS

Most patients exhibited at least one form of metabolic dysregulation (pre-DM or DM, 75.8%; pre-HTN or HTN, 91.1%; pre-DYS or DYS, 84.0%; metabolic syndrome, 76.0%). The majority of patients either did not meet GL treatment goals (DM, 45.7%; HTN, 39.5%; DYS, 22.3%) or were previously undiagnosed (DM, 15.8%; HTN, 13.7%; DYS, 41.7%). Non-GL pharmacotherapy was significantly less effective than GL pharmacotherapy at achieving treatment goals for DM (31.8 vs. 53.2%, p < 0.001) and HTN (43.6 vs. 63.2%, p = 0.007). Patients with concurrent DM, HTN, and DYS (35.5%) were less likely than patients with only one or two of these metabolic diseases to achieve GL treatment goals for HTN (38.1 vs. 72.6%, p < 0.001) and DYS (55.7 vs. 73.8%, p = 0.002). Only 8.0% of these patients achieved treatment goals for all three metabolic comorbidities.

CONCLUSIONS

In this patient group, DM, HTN, and DYS were poorly compensated, even when pharmacotherapy was consistent with published GL. This may be due to disease burden in bariatric surgery candidates or to inadequate medical management prior to presentation.

Comparative study of five different surgical techniques for the treatment of morbid obesity using BAROS

Background

The obesity is an universal disease of epidemic proportions and in a growing prevalence. It is one of the main public health problems and it will be inexorably the largest problem of the developing world. The morbid obesity is associated to serious diseases, reducing the life perspective, increasing the morbility and mortality. Several strategies of losing weight were proposed; however, the bariatric surgeries are today the most effective treatment for this disease. The BAROS is the most simple, practical and efficient method to evaluate the results in the bariatric surgeries.

Aim

To compare five surgical techniques for the treatment of morbid obesity using BAROS.

Method

The sample is constituted of 102 patients submitted to Fobi-Capella (23 patients), Scopinaro (21 patients), duodenal switch (20 patients), vertical banded gastroplasty of Mason (15 patients) and the adjustable gastric band (23 patients), evaluated 12 months after the surgeries using BAROS.

Results

The analysis of the final result of BAROS for the classification demonstrated that good, very good and excellent results were obtained in 100% of the patients in the group of duodenal switch; 91,3% in Fobi-Capella; 85,7% in Scopinaro; 60% in Mason; and 56,5% in adjustable gastric band. The final result of BAROS for the total score demonstrated that the group of duodenal switch obtained 6,3 points; the Fobi-Capella 5,1 points; the Scopinaro 4,8 points; the Mason 3,0 points; and the adjustable gastric band 2,9 points (p<0,0001).

Conclusion

The duodenal switch is the best technique for the surgical treatment of the morbid obesity, in the following 12 months post-surgical clinical procedures, according to BAROS.

Impact of bariatric surgery on life expectancy in severely obese patients with diabetes: a decision analysis

OBJECTIVE

To create a decision analytic model to estimate the balance between treatment risks and benefits for severely obese patients with diabetes.

BACKGROUND

Bariatric surgery leads to many desirable metabolic changes, but long-term impact of bariatric surgery on life expectancy in patients with diabetes has not yet been quantified.

METHODS

We developed a Markov state transition model with multiple Cox proportional hazards models and logistic regression models as inputs to compare bariatric surgery versus no surgical treatment for severely obese diabetic patients. The model is informed by data from 3 large cohorts: (1) 159,000 severely obese diabetic patients (4185 had bariatric surgery) from 3 HMO Research Network sites; (2) 23,000 subjects from the Nationwide Inpatient Sample; and (3) 18,000 subjects from the National Health Interview Survey linked to the National Death Index.

RESULTS

In our main analyses, we found that a 45-year-old woman with diabetes and a body mass index (BMI) of 45 kg/m gained an additional 6.7 years of life expectancy with bariatric surgery (38.4 years with surgery vs 31.7 years without surgery). Sensitivity analyses revealed that the gain in life expectancy decreased with increasing BMI, until a BMI of 62 kg/m is reached, at which point nonsurgical treatment was associated with greater life expectancy. Similar results were seen for both men and women in all age groups.

CONCLUSIONS

For most severely obese patients with diabetes, bariatric surgery seems to improve life expectancy; however, surgery may reduce life expectancy for the super obese with BMIs over 62 kg/m.

Quality and safety in obesity surgery-15 years of Roux-en-Y gastric bypass outcomes from a longitudinal database

BACKGROUND

Most population-based studies lack long-term data, making the reporting of true mortality and outcome rates difficult. An accurate estimate of these rates in a high-risk population is critical for obtaining informed consent, especially for an elective procedure such as Roux-en-Y gastric bypass (RYGB).

OBJECTIVES

To examine the longitudinal outcomes of RYGB.

SETTING

The California Office of Statewide Health Planning and Development (OSHPD) longitudinal database.

METHODS

The OSHPD longitudinal database was queried for patients who underwent RYGB between 1995 and 2009. The primary outcome was mortality rates at 1, 5, and 10 years. Secondary outcomes were marginal ulcer and reoperation. The Cox hazard proportional analysis was used to determine adjusted survival and long-term outcomes for laparoscopic RYGB compared with open RYGB.

RESULTS

The study included 129,432 RYGB patients. Rates of laparoscopy increased from 3% to 35% from 1995 to 2004 and then steeply increased to 80% in 2005 and to 93% in 2009. Overall mortality rate at 1, 5, and 10 years was 2.2%, 4.4%, and 8.1%, respectively; the rates of marginal ulcer were .3%, .7%, and 1%, respectively; and the reoperation rates were .3%, .8%, and 1.2%, respectively. Predictors of poor outcomes were male gender, age, smoking, alcohol, Medicare, Medi-Cal insurance, and Asian or Native American race. The laparoscopic approach was protective against death (hazard ratio [HR] 95% confidence interval [95%CI]: .63[.58-.69]) and long-term complications (HR .78[.72-.85]).

CONCLUSIONS

This longitudinal population study showed high rates of mortality following RYGB, with improved long-term outcomes when the laparoscopic approach was used.

Anti-incretin, Anti-proliferative Action of Dopamine on β-Cells

Human islet β-cells exploit an autocrine dopamine (DA)-mediated inhibitory circuit to regulate insulin secretion. β-Cells also express the DA active transporter and the large neutral amino acid transporter heterodimer enabling them to import circulating DA or its biosynthetic precursor, L-3,4-dihydroxyphenylalanine (L-DOPA). The capacity to import DA or L-DOPA from the extracellular space possibly indicates that DA may be an endocrine signal as well. In humans, a mixed meal stimulus is accompanied by contemporary serum excursions of incretins, DA and L-DOPA, suggesting that DA may act as an anti-incretin as postulated by the foregut hypothesis proposed to explain the early effects of bariatric surgery on type 2 diabetes. In this report, we take a translational step backwards and characterize the kinetics of plasma DA and incretin production after a mixed meal challenge in a rat model and study the integration of incretin and DA signaling at the biochemical level in a rodent β-cell line and islets. We found that there are similar excursions of incretins and DA in rats, as those reported in humans, after a mixed meal challenge and that DA counters incretin enhanced glucose-stimulated insulin secretion and intracellular signaling at multiple points from dampening calcium fluxes to inhibiting proliferation as well as apoptosis. Our data suggest that DA is an important regulator of insulin secretion and may represent 1 axis of a gut level circuit of glucose and β-cell mass homeostasis.

Predictors of metabolic syndrome persistence 1 year after laparoscopic Roux-en-Y gastric bypass

BACKGROUND

Laparoscopic Roux-en-Y gastric bypass (LRYGB) is effective in reversing the metabolic syndrome (MS) in up to 90% of patients.

OBJECTIVES

The aim of this study was to determine predictors of MS persistence 1 year after LRYGB.

SETTING

University Hospital, France.

METHODS

Ninety-one patients with a mean age of 44.4 years and a mean body mass index (BMI) of 43.1 kg/m² meeting the criteria for MS were enrolled in this prospective study. Anthropometric, metabolic, and inflammatory biological parameters were assessed before and 1 year after LRYGB. Patients were divided into 2 groups according to the persistence (MS nonresponders) or resolution of MS (MS responders) 1 year after LRYGB and a comparison was performed at baseline and 1 year after surgery.

RESULTS

Sixty-nine patients (75.8%) underwent remission, while 22 (24.2%) showed persistence of MS 1 year after LRYGB. At baseline the MS nonresponders group presented significantly higher values of fasting plasma glucose (7.8 versus 5.3 mmol/L, P = .004), glycosylated hemoglobin (HbA1c, 7.3% versus 5.9%, P = .0004), triglycerides (TG, 2.37 versus 1.33 mmol/L, P = .006), and homeostasis model assessment of insulin resistance (HOMA-IR, 442.5 versus 256, P = .006). The rate of diabetes was significantly higher in this group (68.2% versus 36.8%, P = .0086), as well as the number of MS components per patient. One year after LRYGB, the MS nonresponders showed a significantly lower excess BMI lost (EBMIL) (56.1% versus 82.4%, P = .00008). On multivariate analysis, baseline levels of TG, glucose metabolism markers and EBMIL were associated with the persistence of MS.

CONCLUSION

Baseline levels of TG, plasma fasting glucose, and HbA1c, as well as history of type 2 diabetes and EBMIL, represent predictors of MS persistence 1 year after LRYGB.