Postprandial hypoglycaemia after Roux-en-Y gastric bypass and the effects of acarbose, sitagliptin, verapamil, liraglutide and pasireotide

The Impact of Cholecystectomy in Patients with Post-Bariatric Surgery Hypoglycemia

BACKGROUND

Metabolic surgery is the foremost treatment for obesity and its associated medical conditions. Nonetheless, post-bariatric hypoglycemia (PBH) emerges as a prevalent complication. PBH pathophysiology implicates heightened insulin and glucagon-like peptide 1 (GLP-1) levels, with bile acids (BA) contributing to GLP-1 release. A plausible association exists between cholecystectomy and PBH, which is attributed to alterations in BA metabolism and ensuing hormonal responses. The objective of this retrospective cohort study was to evaluate the impact of cholecystectomy on PBH pharmacological treatment, diagnostic timelines and metabolic parameters.

MATERIALS AND METHODS

Patients diagnosed with PBH after bariatric surgery were evaluated based on their history of cholecystectomy. Demographic, anthropometric and clinical data were collected. Mixed meal tolerance tests (MMTT) results were compiled to assess metabolic responses.

RESULTS

Of the 131 patients with PBH included in the study, 29 had prior cholecystectomy. The time to PBH diagnosis was similar across groups. Patients with prior cholecystectomy required higher doses of acarbose (p = 0.046), compared to those without prior cholecystectomy. Additionally, MMTT revealed higher insulin (t = 60 min: p = 0.010 and t = 90 min: p = 0.034) and c-peptide levels (t = 60 min: p = 0.008) and greater glycemic variability in patients with prior cholecystectomy (p = 0.049), highlighting the impact of cholecystectomy on glucose metabolism.

CONCLUSION

Our study offers novel insights into PBH pharmacotherapy, indicating that PBH patients with a history of cholecystectomy require elevated doses of acarbose for symptom control than PBH patients without such surgical history. Furthermore, our findings underscore the pivotal role of hyperinsulinism in PBH aetiology, emphasizing the significance of the BA-GLP-1-insulin axis.

Canagliflozin or acarbose versus placebo to ameliorate post-bariatric hypoglycaemia - The HypoBar I randomized clinical trial protocol

INTRODUCTION

Post-bariatric hypoglycaemia (PBH) is a rare yet disabling clinical condition, mostly reported after Roux-en-Y gastric bypass (RYGB) surgery. RYGB is one of the most widely used and effective bariatric procedures. The pathophysiology of PBH remains unclear, and treatment options are limited in effectiveness and/or carry significant side effects. Acarbose slows carbohydrates digestion and absorption and is generally considered first-line pharmacological treatment for PBH but its gastrointestinal side effects limit patient compliance. Canagliflozin inhibits intestinal and renal sodium-dependent glucose absorption and reduces postprandial excursions of glucose, insulin and incretins after RYGB - effects that could be beneficial in ameliorating PBH.

AIMS

The trial aims to investigate how blood glucose levels are affected during daily living in subjects with PBH during treatment with canagliflozin or acarbose compared with placebo, and to study the meal-induced entero-endocrine mechanisms implied in the treatment responses.

METHODS

In a double-blinded, randomized, crossover clinical trial, HypoBar I will investigate the effectiveness in reducing the risk of PBH, safety, ambulatory glucose profile and entero-endocrine responses when PBH is treated with canagliflozin 300 mg twice daily during a 4-week intervention period, compared with acarbose 50 mg thrice daily or placebo.

ETHICS AND DISSEMINATION

HypoBar I is approved by the Local regulatory entities. Results will be published in peer-reviewed journals.

CONCLUSION

If effective, well-tolerated and safe, canagliflozin could be a novel treatment for people with PBH. HypoBar I might also unravel new mechanisms underlying PBH, potentially identifying new treatment targets.

TRIAL REGISTRATION

EudraCT number 2022-000157-87.

EndoBridge 2023: highlights and pearls

EndoBridge 2023 took place on October 20-22, 2023, in Antalya, Turkey. Accredited by the European Council, the 3-day scientific program of the 11th Annual Meeting of EndoBridge included state-of-the-art lectures and interactive small group discussion sessions incorporating interesting and challenging clinical cases led by globally recognized leaders in the field and was well attended by a highly diverse audience. Following its established format over the years, the program provided a comprehensive update across all aspects of endocrinology and metabolism, including topics in pituitary, thyroid, bone, and adrenal disorders, neuroendocrine tumors, diabetes mellitus, obesity, nutrition, and lipid disorders. As usual, the meeting was held in English with simultaneous translation into Russian, Arabic, and Turkish. The abstracts of clinical cases presented by the delegates during oral and poster sessions have been published in JCEM Case Reports. Herein, we provide a paper on highlights and pearls of the meeting sessions covering a wide range of subjects, from thyroid nodule stratification to secondary osteoporosis and from glycemic challenges in post-bariatric surgery to male hypogonadism. This report emphasizes the latest developments in the field, along with clinical approaches to common endocrine issues. The 12th annual meeting of EndoBridge will be held on October 17-20, 2024 in Antalya, Turkey.

Postbariatric surgery hypoglycemia: Nutritional, pharmacological and surgical perspectives

Post-bariatric hypoglycaemia (PBH) is a metabolic complication of bariatric surgery (BS), consisting of low post-prandial glucose levels in patients having undergone bariatric procedures. While BS is currently the most effective and relatively safe treatment for obesity and its complications, the development of PBH can significantly impact patients' quality of life and mental health. The diagnosis of PBH is still challenging, considering the lack of definitive and reliable diagnostic tools, and the fact that this condition is frequently asymptomatic. However, PBH's prevalence is alarming, involving up to 88% of the post-bariatric population, depending on the diagnostic tool, and this may be underestimated. Given the prevalence of obesity soaring, and an increasing number of bariatric procedures being performed, it is crucial that physicians are skilled to diagnose PBH and promptly treat patients suffering from it. While the milestone of managing this condition is nutritional therapy, growing evidence suggests that old and new pharmacological approaches may be adopted as adjunct therapies for managing this complex condition.

Dasiglucagon Treatment for Postprandial Hypoglycemia After Gastric Bypass: A Randomized, Double-Blind, Placebo-Controlled Trial

OBJECTIVE

Postbariatric hypoglycemia affects >50% of individuals who have undergone Roux-en-Y gastric bypass surgery. Despite the often debilitating nature of this complication, existing treatment options are limited and often inefficient. Dasiglucagon is a stable glucagon analog available in a ready-to-use formulation and was recently shown to mitigate postbariatric hypoglycemia in experimental settings. Here, we aimed to evaluate the hypoglycemic hindering potential of dasiglucagon in an outpatient trial.

RESEARCH DESIGN AND METHODS

We conducted a randomized, double-blind, placebo-controlled, crossover, proof-of-concept study at the Center for Clinical Metabolic Research at Gentofte Hospital in Denmark. The study included 24 individuals who had undergone Roux-en-Y gastric bypass surgery (n = 23 women) with continuous glucose monitor-verified postbariatric hypoglycemia (≥15 min at <3.9 mmol/L three or more times per week) randomly assigned to two treatment periods of 4 weeks of self-administered subcutaneous dasiglucagon at 120 μg or placebo. The primary and key secondary outcomes were continuous glucose monitor-captured percentage of time in level 1 and 2 hypoglycemia (<3.9 and <3.0 mmol/L), respectively.

RESULTS

Compared with placebo, treatment with dasiglucagon significantly reduced time in level 1 hypoglycemia by 33% (-1.2 percentage points; 95% CI -2.0 to -0.5; P = 0.002) and time in level 2 hypoglycemia by 54% (-0.4 percentage points; 95% CI -0.6 to -0.2; P < 0.0001). Furthermore, dasiglucagon corrected hypoglycemia within 15 min in 401 of 412 self-administrations, compared with 104 of 357 placebo self-administrations (97.3% vs. 29.1% correction of hypoglycemia rate; P < 0.001). Dasiglucagon was generally well tolerated, with mostly mild to moderate adverse events of nausea.

CONCLUSIONS

Compared with placebo, 4 weeks of self-administered dasiglucagon effectively reduced clinically relevant hypoglycemia in individuals who had undergone Roux-en-Y gastric bypass surgery.

Strategies to Maintain the Remission of Diabetes Following Metabolic Surgery

Obesity is a major risk factor for type 2 diabetes mellitus (T2DM). Bariatric surgery is the most effective means of inducing weight loss, and can ameliorate or induce the remission of obesity-related metabolic comorbidities, including T2DM. The guidelines for the management of T2DM emphasize weight management and recommend metabolic surgery for the treatment of T2DM accompanied by obesity. However, despite the clear beneficial effects of metabolic surgery, only 20-50% of patients who experience remission will stay in remission over the long term. Moreover, the beneficial effects of metabolic surgery tend to diminish with time, and a subset of patients experience a relapse of their diabetes. Therefore, in the present review, we discuss potential strategies for the maintenance of diabetic remission following metabolic surgery.

An Imbalance of Pathophysiologic Factors in Late Postprandial Hypoglycemia Post Bariatric Surgery: A Narrative Review

With a rise in obesity and more patients opting for bariatric surgery, it becomes crucial to understand associated complications like postprandial hypoglycemia (PPH). After bariatric surgery, significant changes are seen in insulin sensitivity, beta cell function, glucagon-like peptide 1 (GLP-1) levels, the gut microbiome, and bile acid metabolism. And in a small subset of patients, exaggerated imbalances in these functional and metabolic processes lead to insulin-glucose mismatch and hypoglycemia. The main treatment for PPH involves dietary modifications. For those that do not respond, medications or surgical interventions are considered to reverse some of the imbalances. We present a few case reports of patients that safely tolerated GLP-1 agonists. However, larger randomized control trials are needed to further characterize PPH and understand its treatment.

Diagnosis and management of post-bariatric surgery hypoglycemia

INTRODUCTION

While bariatric surgery remains the most effective treatment for obesity that allows substantial weight loss with improvement and possibly remission of obesity-associated comorbidities, some postoperative complications may occur. Managing physicians need to be familiar with the common problems to ensure timely and effective management. Of these complications, postoperative hypoglycemia is an increasingly recognized complication of bariatric surgery that remains underreported and underdiagnosed.

AREA COVERED

This article highlights the importance of identifying hypoglycemia in patients with a history of bariatric surgery, reviews pathophysiology and addresses available nutritional, pharmacological and surgical management options. Systemic evaluation including careful history taking, confirmation of hypoglycemia and biochemical assessment is essential to establish accurate diagnosis. Understanding the weight-dependent and weight-independent mechanisms of improved postoperative glycemic control can provide better insight into the causes of the exaggerated responses that lead to postoperative hypoglycemia.

EXPERT OPINION

Management of post-operative hypoglycemia can be challenging and requires a multidisciplinary approach. While dietary modification is the mainstay of treatment for most patients, some patients may benefit from pharmacotherapy (e.g. GLP-1 receptor antagonist); Surgery (e.g. reversal of gastric bypass) is reserved for unresponsive severe cases. Additional research is needed to understand the underlying pathophysiology with a primary aim in optimizing diagnostics and treatment options.

Continuous glucose monitoring in patients with post-bariatric hypoglycaemia reduces hypoglycaemia and glycaemic variability

AIM

To determine whether continuous glucose monitoring (CGM) can reduce hypoglycaemia in patients with post-bariatric hypoglycaemia (PBH).

MATERIALS AND METHODS

In an open-label, nonrandomized, pre-post design with sequential assignment, CGM data were collected in 22 individuals with PBH in two sequential phases: (i) masked (no access to sensor glucose or alarms); and (ii) unmasked (access to sensor glucose and alarms for low or rapidly declining sensor glucose). Twelve participants wore the Dexcom G4 device for a total of 28 days, while 10 wore the Dexcom G6 device for a total of 20 days.

RESULTS

Participants with PBH spent a lower percentage of time in hypoglycaemia over 24 hours with unmasked versus masked CGM (<3.3 mM/L, or <60 mg/dL: median [median absolute deviation {MAD}] 0.7 [0.8]% vs. 1.4 [1.7]%, P = 0.03; <3.9 mM/L, or <70 mg/dL: median [MAD] 2.9 [2.5]% vs. 4.7 [4.8]%; P = 0.04), with similar trends overnight. Sensor glucose data from the unmasked phase showed a greater percentage of time spent between 3.9 and 10 mM/L (70-180 mg/dL) (median [MAD] 94.8 [3.9]% vs. 90.8 [5.2]%; P = 0.004) and lower glycaemic variability over 24 hours (median [MAD] mean amplitude of glycaemic excursion 4.1 [0.98] vs. 4.4 [0.99] mM/L; P = 0.04). During the day, participants also spent a greater percentage of time in normoglycaemia with unmasked CGM (median [MAD] 94.2 [4.8]% vs. 90.9 [6.2]%; P = 0.005), largely due to a reduction in hyperglycaemia (>10 mM/L, or 180 mg/dL: median [MAD] 1.9 [2.2]% vs. 3.9 [3.6]%; P = 0.02).

CONCLUSIONS

Real-time CGM data and alarms are associated with reductions in low sensor glucose, elevated sensor glucose, and glycaemic variability. This suggests CGM allows patients to detect hyperglycaemic peaks and imminent hypoglycaemia, allowing dietary modification and self-treatment to reduce hypoglycaemia. The use of CGM devices may improve safety in PBH, particularly for patients with hypoglycaemia unawareness.

Use of Continuous Glucose Monitoring in Patients Following Bariatric Surgery: A Scoping Review

The objective of this scoping review was to summarize the emerging literature on the use of continuous glucose monitoring (CGM) in post-bariatric surgery patients, with a focus on its features (e.g., device, mode, and accuracy), as well as purposes and outcomes of utilization. Three databases (PubMed, EMBASE, and Web of Science) were searched to obtain relevant studies. Results suggested that most studies used CGM for 3-7 days under blinded mode. Accuracy data were available in only one study, which reported a mean absolute relative difference of 21.7% for Freestyle Libre. The primary applications of CGM were for elucidating glucose patterns and assessing glycemic treatment outcomes. No study has tested the effect of CGM as an intervention strategy to enhance glucose control.

Practical guideline on obesity care in patients with gastrointestinal and liver diseases - Joint ESPEN/UEG guideline

BACKGROUND

Patients with chronic gastrointestinal disease such as inflammatory bowel disease (IBD), irritable bowel syndrome (IBS), celiac disease, gastroesophageal reflux disease (GERD), pancreatitis, and chronic liver disease (CLD) often suffer from obesity because of coincidence (IBD, IBS, celiac disease) or related pathophysiology (GERD, pancreatitis and CLD). It is unclear if such patients need a particular diagnostic and treatment that differs from the needs of lean gastrointestinal patients. The present guideline addresses this question according to current knowledge and evidence.

OBJECTIVE

The present practical guideline is intended for clinicians and practitioners in general medicine, gastroenterology, surgery and other obesity management, including dietitians and focuses on obesity care in patients with chronic gastrointestinal diseases.

METHODS

The present practical guideline is the shortened version of a previously published scientific guideline developed according to the standard operating procedure for ESPEN guidelines. The content has been re-structured and transformed into flow-charts that allow a quick navigation through the text.

RESULTS

In 100 recommendations (3× A, 33× B, 24 × 0, 40× GPP, all with a consensus grade of 90% or more) care of gastrointestinal patients with obesity - including sarcopenic obesity - is addressed in a multidisciplinary way. A particular emphasis is on CLD, especially metabolic associated liver disease, since such diseases are closely related to obesity, whereas liver cirrhosis is rather associated with sarcopenic obesity. A special chapter is dedicated to obesity care in patients undergoing bariatric surgery. The guideline focuses on adults, not on children, for whom data are scarce. Whether some of the recommendations apply to children must be left to the judgment of the experienced pediatrician.

CONCLUSION

The present practical guideline offers in a condensed way evidence-based advice how to care for patients with chronic gastrointestinal diseases and concomitant obesity, an increasingly frequent constellation in clinical practice.

Medical and surgical treatment of postbariatric hypoglycaemia: Retrospective data from daily practice

AIM

To evaluate medical and surgical treatment of postbariatric hypoglycaemia (PBH) in daily practice.

MATERIALS AND METHODS

Retrospective data were extracted from medical records from four hospitals. PBH was defined by neuroglycopenic symptoms together with a documented glucose <3.0 mmol/L in the postprandial setting after previous bariatric surgery. Data were scored semiquantitatively on efficacy and side effects by two reviewers independently. Duration of efficacy and of use were calculated.

RESULTS

In total, 120 patients were included with a median follow-up of 27 months with a mean baseline age of 41 years, total weight loss of 33% and glucose nadir 2.3 mmol/L. Pharmacotherapy consisted of acarbose, diazoxide, short- and long-acting octreotide and glucagon-like peptide-1 receptor agonist analogues (liraglutide and semaglutide) with an overall efficacy in 45%-75% of patients. Combination therapy with two drugs was used by 30 (25%) patients. The addition of a second drug was successful in over half of the patients. Long-acting octreotide and the glucagon-like peptide-1 receptor agonist analogues scored best in terms of efficacy and side effects with a median duration of use of 35 months for octreotide. Finally, 23 (19%) patients were referred for surgical intervention. Efficacy of the surgical procedures, pouch banding, G-tube placement in remnant stomach and Roux-en-Y gastric bypass reversal, pooled together, was 79% with a median duration of initial effect of 13 months.

CONCLUSIONS

In daily practice, pharmacotherapy for PBH was successful in half to three quarters of patients. Combination therapy was often of value. One in five patients finally needed a surgical procedure, with overall good results.

The efficacy of GLP-1RAs for the management of postprandial hypoglycemia following bariatric surgery: a systematic review

OBJECTIVE

Postprandial hyperinsulinemic hypoglycemia with neuroglycopenia is an increasingly recognized complication of Roux-en-Y gastric bypass and gastric sleeve surgery that may detrimentally affect patient quality of life. One likely causal factor is glucagon-like peptide-1 (GLP-1), which has an exaggerated rise following ingestion of carbohydrates after bariatric surgery. This paper sought to assess the role of GLP-1 receptor agonists (GLP-1RAs) in managing postprandial hypoglycemia following bariatric surgery.

METHODS

MEDLINE, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), ClinicalTrials.gov, and Scopus were systematically and critically appraised for all peer-reviewed publications that suitably fulfilled the inclusion criteria established a priori. This systematic review was developed according to the Preferred Reporting Items for Systematic Review and Meta-Analyses Protocols (PRISMA-P). It followed methods outlined in the Cochrane Handbook for Systematic Reviews of Interventions and is registered with PROSPERO (International Prospective Register of Systematic Reviews; identifier CRD420212716429).

RESULTS AND CONCLUSIONS

Postprandial hyperinsulinemic hypoglycemia remains a notoriously difficult to manage metabolic complication of bariatric surgery. This first, to the authors' knowledge, systematic review presents evidence suggesting that use of GLP-1RAs does not lead to an increase of hypoglycemic episodes, and, although this approach may appear counterintuitive, the findings suggest that GLP-1RAs could reduce the number of postprandial hypoglycemic episodes and improve glycemic variability.

Medical Nutrition Therapy and Other Approaches to Management of Post-bariatric Hypoglycemia: A Team-Based Approach

PURPOSE OF REVIEW

This manuscript provides a review of post-bariatric hypoglycemia (PBH) with a special focus on the role of the registered dietitian-nutritionist (RDN) and medical nutrition therapy (MNT) recommendations as foundational for management.

RECENT FINDINGS

As the number of bariatric surgeries rises yearly, with 256,000 performed in 2019, PBH is an increasingly encountered late complication. Following Roux-en-Y (RYGB) or vertical sleeve gastrectomy (VSG), about 1/3 of patients report symptoms suggestive of at least mild postprandial hypoglycemia, with severe and/or medically confirmed hypoglycemia in 1-10%. Anatomical alterations, changes in GLP1 and other intestinally derived hormones, excessive insulin response, reduced insulin clearance, impaired counterregulatory hormone response to hypoglycemia, and other factors contribute to PBH. MNT is the cornerstone of multidisciplinary treatment, with utilization of personal continuous glucose monitoring to improve safety when possible. While many individuals require pharmacotherapy, there are no currently approved medications for PBH. Increasing awareness and identification of individuals at risk for or with PBH is critical given the potential impact on safety, nutrition, and quality of life. A team-based approach involving the individual, the RDN, and other clinicians is essential in providing ongoing assessment and individualization of MNT in the long-term management of PBH.

Recommendations for the diagnosis and treatment of hypoglycaemia after bariatric surgery

Postprandial hyperinsulinaemic hypoglycaemia is a common complication of bariatric surgery. Although in general its evolution is mild and self-limited, it can lead to neuroglycopaenia and compromise the patient's safety and quality of life. The aim of this document is to offer some recommendations to facilitate the clinical care of these complex patients, reviewing the aetiopathogenesis, its diagnosis and treatment that, sequentially, will include dietary and pharmacological measures and surgery in refractory cases. In the absence of high-quality studies, the diagnostic and therapeutic approach proposed is based on the consensus of experts of the Grupo de Obesidad de la Sociedad Española de Endocrinología y Nutrición [Obesity Group of the Spanish Society of Endocrinology and Nutrition], GOSEEN. Those undergoing bariatric surgery should be informed of the possibility of developing this complication.

European guideline on obesity care in patients with gastrointestinal and liver diseases - Joint European Society for Clinical Nutrition and Metabolism / United European Gastroenterology guideline

BACKGROUND

Patients with chronic gastrointestinal (GI) disease such as inflammatory bowel disease (IBD), irritable bowel syndrome (IBS), celiac disease, gastroesophageal reflux disease (GERD), pancreatitis, and chronic liver disease (CLD) often suffer from obesity because of coincidence (IBD, IBS, celiac disease) or related pathophysiology (GERD, pancreatitis and CLD). It is unclear if such patients need a particular diagnostic and treatment that differs from the needs of lean GI patients. The present guideline addresses this question according to current knowledge and evidence.

OBJECTIVE

The objective of the guideline is to give advice to all professionals working in the field of gastroenterology care including physicians, surgeons, dietitians and others how to handle patients with GI disease and obesity.

METHODS

The present guideline was developed according to the standard operating procedure for European Society for Clinical Nutrition and Metabolism guidelines, following the Scottish Intercollegiate Guidelines Network grading system (A, B, 0, and good practice point [GPP]). The procedure included an online voting (Delphi) and a final consensus conference.

RESULTS

In 100 recommendations (3x A, 33x B, 24x 0, 40x GPP, all with a consensus grade of 90% or more) care of GI patients with obesity - including sarcopenic obesity - is addressed in a multidisciplinary way. A particular emphasis is on CLD, especially fatty liver disease, since such diseases are closely related to obesity, whereas liver cirrhosis is rather associated with sarcopenic obesity. A special chapter is dedicated to obesity care in patients undergoing bariatric surgery. The guideline focuses on adults, not on children, for whom data are scarce. Whether some of the recommendations apply to children must be left to the judgment of the experienced pediatrician.

CONCLUSION

The present guideline offers for the first time evidence-based advice how to care for patients with chronic GI diseases and concomitant obesity, an increasingly frequent constellation in clinical practice.

European guideline on obesity care in patients with gastrointestinal and liver diseases - Joint ESPEN/UEG guideline

BACKGROUND

Patients with chronic gastrointestinal (GI) disease such as inflammatory bowel disease (IBD), irritable bowel syndrome (IBS), celiac disease, gastroesophageal reflux disease (GERD), pancreatitis, and chronic liver disease (CLD) often suffer from obesity because of coincidence (IBD, IBS, celiac disease) or related pathophysiology (GERD, pancreatitis and CLD). It is unclear if such patients need a particular diagnostic and treatment that differs from the needs of lean GI patients. The present guideline addresses this question according to current knowledge and evidence.

OBJECTIVE

The objective of the guideline is to give advice to all professionals working in the field of gastroenterology care including physicians, surgeons, dietitians and others how to handle patients with GI disease and obesity.

METHODS

The present guideline was developed according to the standard operating procedure for ESPEN guidelines, following the Scottish Intercollegiate Guidelines Network (SIGN) grading system (A, B, 0, and good practice point (GPP)). The procedure included an online voting (Delphi) and a final consensus conference.

RESULTS

In 100 recommendations (3x A, 33x B, 24x 0, 40x GPP, all with a consensus grade of 90% or more) care of GI patients with obesity - including sarcopenic obesity - is addressed in a multidisciplinary way. A particular emphasis is on CLD, especially fatty liver disease, since such diseases are closely related to obesity, whereas liver cirrhosis is rather associated with sarcopenic obesity. A special chapter is dedicated to obesity care in patients undergoing bariatric surgery. The guideline focuses on adults, not on children, for whom data are scarce. Whether some of the recommendations apply to children must be left to the judgment of the experienced pediatrician.

CONCLUSION

The present guideline offers for the first time evidence-based advice how to care for patients with chronic GI diseases and concomitant obesity, an increasingly frequent constellation in clinical practice.

Dasiglucagon Effectively Mitigates Postbariatric Postprandial Hypoglycemia: A Randomized, Double-Blind, Placebo-Controlled, Crossover Trial

OBJECTIVE

To investigate the efficacy and safety of dasiglucagon, a novel stable glucagon analog in a liquid formulation, in Roux-en-Y gastric bypass (RYGB)-operated individuals suffering from postbariatric hypoglycemia (PBH).

RESEARCH DESIGN AND METHODS

In a randomized, double-blind, placebo-controlled, crossover trial, 10 RYGB-operated participants with continuous glucose monitoring-verified PBH were randomly assigned to 3 trial days, each consisting of a 240-min standardized liquid mixed-meal test with the subcutaneous injection of placebo or 80 μg or 200 μg dasiglucagon.

RESULTS

Compared with placebo, treatment with both 80 and 200 μg dasiglucagon raised nadir plasma glucose (PG) (placebo: 3.0 ± 0.2 mmol/L [mean ± SEM]; 80 μg dasiglucagon: 3.9 ± 0.3 mmol/L, P = 0.002; 200 μg dasiglucagon: 4.5 ± 0.2 mmol/L, P = 0.0002) and reduced time in hypoglycemia (PG <3.9 mmol/L) by 70.0 min (P = 0.030 and P = 0.008).

CONCLUSIONS

Single-dose administration of dasiglucagon effectively mitigated postprandial hypoglycemia.

Pramlintide for post-bariatric hypoglycaemia

AIMS

The aim of this study was to examine the hypothesis that pramlintide would reduce hypoglycaemia by slowing gastric emptying and reducing postprandial glucagon secretion, thus limiting postprandial glycaemic excursions and insulin secretion, and thus to determine the efficacy of pramlintide on frequency and severity of hypoglycaemia in post-bariatric hypoglycaemia (PBH).

MATERIALS AND METHODS

Participants with PBH following gastric bypass were recruited from outpatient clinics at the Joslin Diabetes Center, Boston, Massachusetts for an open-label study of pramlintide efficacy over 8 weeks. Twenty-three participants were assessed for eligibility, 20 participants had at least one pramlintide dose, and 14 completed the study. A mixed-meal tolerance test (MMTT) was performed at baseline and after 8 weeks of subcutaneous pramlintide with a sequential dose increase to a maximum of 120 micrograms (mean 69 ± 32 mcg) three times daily. The primary endpoint was change in glucose excursions during the MMTT. Secondary measures included MMTT insulin response, satiety and dumping score, percentage time with sensor glucose (SG) <3.9 mM, and number of days with minimum SG <3 mM, during masked continuous glucose monitoring.

RESULTS

There were no differences in MMTT glucose, glucagon or insulin between baseline and post treatment. We observed no significant change in satiety or dumping scores. The overall frequency of low SG values did not change, although there was substantial inter-individual variability.

CONCLUSIONS

In PBH, pramlintide does not modulate glycaemic or insulin responses, satiety, or dumping scores during an MMTT and does not impact glycaemic excursions or decrease low SG levels in the outpatient setting.

Evaluation and Management of Patients Referred for Post-Bariatric Surgery Hypoglycemia at a Tertiary Care Center

PURPOSE

Following bariatric surgery, patients can develop non-specific symptoms self-described as hypoglycemia. However, confirming hypoglycemia can be technically challenging, and therefore, these individuals are frequently treated empirically. This study aimed to describe what diagnostic evaluation and therapeutic interventions patients referred for post-bariatric surgery hypoglycemia undergo.

METHODS

Retrospective observational cohort study of patients with a history of bariatric surgery was evaluated for post-bariatric surgery hypoglycemia in a tertiary referral center from 2008 to 2017. We collected demographic and bariatric surgery information, clinical presentation of symptoms referred to as hypoglycemia, laboratory and imaging studies performed to evaluate these symptoms, and symptom management and outcomes.

RESULTS

A total of 60/2450 (2.4%) patients who underwent bariatric surgery were evaluated in the Department of Endocrinology for hypoglycemia-related symptoms. The majority were middle-aged women without type 2 diabetes who had undergone Roux-en-Y gastric bypass. Thirty-nine patients (65%) completed a biochemical assessment for hypoglycemia episodes. Six (10%) had confirmed hypoglycemia by Whipple's triad, and four (6.7%) met the criteria for post-bariatric surgery hypoglycemia based on clinical and biochemical criteria. All patients were recommended dietary modification as the initial line of treatment, and this intervention resulted in most patients reporting at least some improvement in their symptoms. Eight patients (13%) were prescribed pharmacotherapy, and two patients required additional interventions for symptom control.

CONCLUSIONS

In our experience, evaluation for hypoglycemia-related symptoms after bariatric surgery was rare. Hypoglycemia was confirmed in the minority of patients. Even without establishing a diagnosis of hypoglycemia, dietary changes were a helpful strategy for symptom management for most patients.

Neurotensin secretion after Roux-en-Y gastric bypass, sleeve gastrectomy, and truncal vagotomy with pyloroplasty

OBJECTIVE

Neurotensin (NT) is released from enteroendocrine cells and lowers food intake in rodents. We evaluated postprandial NT secretion in humans after surgeries associated with accelerated small intestinal nutrient delivery, and after Roux-en-Y gastric bypass (RYGB) when glucagon-like peptide-1 (GLP-1) signalling and dipeptidyl peptidase 4 (DPP-4) were inhibited, and during pharmacological treatments influencing entero-pancreatic functions.

METHODS

We measured NT concentrations in plasma from meal studies: (I) after truncal vagotomy with pyloroplasty (TVP), cardia resection +TVP (CTVP), and matched controls (n = 10); (II) after RYGB, sleeve gastrectomy (SG), and in matched controls (n = 12); (III) after RYGB (n = 11) with antagonism of GLP-1 signalling using exendin(9-39) and DPP-4 inhibition using sitagliptin; (IV) after RYGB (n = 11) during a run-in period and subsequent treatment with, sitagliptin, liraglutide (GLP-1 receptor agonist), verapamil (calcium antagonist), acarbose (alpha glucosidase inhibitor), and pasireotide (somatostatin analogue), respectively.

RESULTS

(I) NT secretion was similar after TVP/CTVP (p = 0.9), but increased vs. controls (p < 0.0001). (II) NT secretion was increased after RYGB vs. SG and controls (p < 0.0001). NT responses were similar in SG and controls (p = 0.3), but early postprandial NT concentrations were higher after SG (p < 0.05). (III) Exendin (9-39) and sitagliptin did not change NT responses vs placebo (p > 0.2), but responses were lower during sitagliptin vs. exendin(9-39) (p = 0.03). (IV) Pasireotide suppressed NT secretion (p = 0.004). Sitagliptin tended to lower NT secretion (p = 0.08). Liraglutide, verapamil, and acarbose had no effect (p > 0.9).

CONCLUSION

Neurotensin secretion is increased after surgeries associated with accelerated gastric emptying and lowered by pasireotide.

Use of continuous glucose monitoring in obesity research: A scoping review

BACKGROUND

This scoping review provides a timely synthesis of the use of continuous glucose monitoring in obesity research with considerations to adherence to continuous glucose monitor devices and metrics most frequently reported.

METHODS

This scoping review was conducted adhering to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) checklist. Eligible studies (n = 31) evaluated continuous glucose monitor use in research on participants, of all ages, with overweight or obesity.

RESULTS

Reviewed studies varied in duration from one to 84 days (mean: 8.74 d, SD 15.2, range 1-84 d) with 889 participants total (range: 11-118 participants). Across all studies, the mean percent continuous glucose monitor wear time (actual/intended wear time in days) was 92% (numerator - mean: 266.1 d, SD: 452, range: 9-1596 d/denominator - mean: 271.6 d, SD: 451.5, range: 9-1596 d). Continuous glucose monitoring was utilized to provide biofeedback (n = 2, 6%), monitor dietary adherence (n = 2, 6%), and assess glycemic variability (n = 29, 93%). The most common variability metrics reported were standard deviation (n = 19, 62%), area under the curve (n = 12, 39%), and glycemic range (n = 12, 39%).

CONCLUSIONS

Available evidence suggests that continuous glucose monitoring is a well-tolerated and versatile tool for obesity research in pediatric and adult patients. Future investigation is needed to substantiate the feasibility and utility of continuous glucose monitors in obesity research and maximize comparability across studies.

Unklare Lymphadenopathie mit Panzytopenie bei einer Patientin mit rezidivierenden Hypoglykämien

Eine Patientin wurde aufgrund rezidivierender postprandialer Hypoglykämien nach Roux-en-Y-Magenbypass mit Diazoxid behandelt, nachdem eine Ernährungsumstellung keine Symptomlinderung erzielt hatte. Nach Eindosierung von Diazoxid mit guter Akutverträglichkeit wurde die Patientin entlassen. Eine Woche nach Therapieeinleitung kam es zu einer Lymphadenopathie und Panzytopenie. Es fanden sich keine Hinweise auf das Vorliegen eines Infekts. Nach Absetzen von Diazoxid sistierten die Beschwerden. Unser Fallbericht weist auf seltene unerwünschte hämatologische Arzneimittelwirkungen unter Diazoxid hin.

Effectiveness of beinaglutide in a patient with late dumping syndrome after gastrectomy: A case report

RATIONALE

Dumping syndrome is a frequent and potentially severe complication after gastric surgery. Beinaglutide, a recombinant human glucagon-like peptide-1 (GLP-1) which shares 100% homology with human GLP-1(7-36), has never been reported in the treatment of dumping syndrome before.

PATIENT CONCERNS

The patient had undergone distal gastrectomy for gastric signet ring cell carcinoma 16 months ago. He presented with symptoms of paroxysmal palpitation, sweating, and dizziness for 4 months.

DIAGNOSIS

He was diagnosed with late dumping syndrome.

INTERVENTIONS AND OUTCOMES

The patient was treated with dietary changes and acarbose for 4 months before admitted to our hospital. The treatment with dietary changes and acarbose did not prevent postprandial hyperinsulinemia and hypoglycemia according to the 75 g oral glucose tolerance test (OGTT) and continuous glucose monitoring (CGM) on admission.Therefore, the patient was treated with beinaglutide 0.1 mg before breakfast and lunch instead of acarbose. After the treatment of beinaglutide for 1 month, OGTT showed a reduction in postprandial hyperinsulinemia compared with before starting treatment, and the time in the range of 3.9 to 10 mmol/L became 100% in CGM. No side effect was observed in this patient during beinaglutide treatment.

LESSONS

These findings suggest that beinaglutide may be effective for treating post-gastrectomy late dumping syndrome.

Identification of curcumin as a potential α-glucosidase and dipeptidyl-peptidase 4 inhibitor: Molecular docking study, in vitro and in vivo biological evaluation

Natural compounds have tremendous potential to regulate glucose metabolism, but conventional methods for studying their bioactivities are usually labor intensive. Here, hypoglycemic properties in 22 selected food-derived compounds were examined using molecular docking. The results indicated that curcumin is an inhibitor of both α-glucosidase and dipeptidyl-peptidase 4 (DPP-4), which are important for glycemic control. These effects of curcumin were also confirmed by enzymatic determination in vitro. Furthermore, curcumin significantly improved diet-induced hyperglycemia (e.g., fasting plasma glucose levels and glycogen storage in muscle or liver) in mice. This might be attributed to its inhibitory effects on the activities of α-glucosidase and DPP-4 in vivo. Curcumin also upregulated the expression of genes (e.g., glucagon-like peptide 1) related to DPP-4 activity in the small intestine. In conclusion, curcumin is a potential ingredient of functional foods used for diet-induced hyperglycemia management. PRACTICAL APPLICATIONS: Curcumin has been widely used as a colorant in the food industry. Moreover, a growing number of studies have described its diverse biological functions, such as anti-inflammatory, anti-oxidant, and anti-angiogenic activities. Thus, curcumin is regarded as a potential ingredient in functional foods. Our results highlighted the hyperglycemic effect of curcumin, suggesting that curcumin may be included in food products for hyperglycemic patients.

Canagliflozin: A New Therapeutic Option in Patients That Present Postprandial Hyperinsulinemic Hypoglycemia after Roux-en-Y Gastric Bypass: A Pilot Study

INTRODUCTION

Roux-en-Y gastric bypass (RYGB) is the most common surgical procedure for morbid obesity. However, it can present serious late complications, like postprandial hyperinsulinemic hypoglycemia (PHH). Recent data suggested an increase in intestinal SGLT-1 after RYGB. However, there is no data on the inhibition of SGLT-1 to prevent PHH in patients with prior RYBG. On this basis, we aimed to evaluate (a) the effect of canagliflozin 300 mg on the response to 100 g glucose overload (oral glucose tolerance test [OGTT]); (b) the pancreatic response after intra-arterial calcium stimulation in the context of PHH after RYGB.

MATERIALS AND METHODS

This is a prospective pilot study including patients (n = 21) with PHH after RYGB, matched by age and gender with healthy controls (n = 5). Basal OGTT and after 2 weeks of daily 300 mg of canagliflozin was performed in all cases. In addition, venous sampling after intra-arterial calcium stimulation of the pancreas was performed in 10 cases.

RESULTS

OGTT after canagliflozin showed a significant reduction of plasma glucose levels (minute 30: 161.5 ± 36.22 vs. 215.9 ± 58.11 mg/dL; minute 60: 187.46 ± 65.88 vs. 225.9 ± 85.60 mg/dL, p < 0.01) and insulinemia (minute 30: 95.6 ± 27.31 vs. 216.35 ± 94.86 mg/dL, p = 0.03; minute 60: 120.85 ± 94.86 vs. 342.64 ± 113.32 mIU/L, p < 0.001). At minute 180, a significant reduction (85.7%) of the rate of hypoglycemia was observed after treatment with canagliflozin (p < 0.00001). All cases presented normal pancreatic response after intra-arterial calcium administration.

CONCLUSION

Canagliflozin (300 mg) significantly decreased glucose absorption and prevented PHH after 100 g OGTT in patients with RYGB. Our results suggest that canagliflozin could be a new therapeutic option for patients that present PHH after RYGB.

Patient involvement to inform the design of a clinical trial in postbariatric hypoglycaemia

Background

Bariatric surgery may lead to symptomatic postprandial hypoglycaemia as a major side effect without established therapy so far. We aimed to develop an evidence-based study design of a clinical trial that tests treatment options and can provide useful patient-relevant evidence.

Methods

We searched systematically for guidance of core outcome sets to determine the most relevant types of outcomes and duration of such a trial. Our search comprised literature databases, a database of core outcome sets and self-help organizations. We then developed a simple online questionnaire based on interviews with German-speaking patients with postprandial hypoglycaemia after bariatric surgery. We recruited participants by reaching out to all German speaking endocrinologists in Switzerland and large Swiss bariatric centres. We asked for preferences regarding outcome types and acceptable duration of being included in a corresponding clinical trial.

Results

The literature search did not identify evidence-based guidance for informing our study design. Experience of clinical and research routine as well as patient interviews helped in identifying potential outcomes and the design of an online questionnaire. Therein, a total of 29 persons started the questionnaire and 22 answered questions related to the primary outcome. Of these, 17 (77.3%) deemed quality of life more relevant as primary outcome than the rate of hypoglycaemic episodes. A trial length of four weeks or longer was regarded as acceptable for 19 of 21 respondents to this question (91.4%) and of six months or longer for 12 respondents (56%).

Conclusions

In situations with no other guidance, a simple questionnaire may help to inform trial design decisions. This study identifies a patient preference for “quality of life” as a primary outcome and supports the evidence-based conception of a patient-centred clinical trial in postbariatric hypoglycaemia.

Supplementary Information

Supplementary information accompanies this paper at 10.1186/s12874-020-01171-z.

Guidelines for gastrostomy tube placement and enteral nutrition in patients with severe, refractory hypoglycemia after gastric bypass

BACKGROUND

Postbariatric hypoglycemia (PBH) affects up to 38% of Roux-en-Y gastric bypass (RYGB) patients. Severe cases are refractory to diet and medications. Surgical treatments including bypass reversal and pancreatectomy are highly morbid and hypoglycemia often recurs. We have developed a highly effective method of treatment by which enteral nutrition administered through a gastrostomy (G) tube placed in the remnant stomach replaces oral diet: if done correctly this reverses hyperinsulinemia and hypoglycemia, yielding substantial health and quality of life benefits for severely affected patients.

OBJECTIVES

To provide clinical guidelines for placement of a G-tube to treat postRYGB hypoglycemia, including candidate selection, preoperative evaluation, surgical considerations, and post-RYGB management.

SETTING

Stanford University Hospital and Clinics.

METHODS

Based on our relatively large experience with placing and managing G-tubes for PBH treatment, an interdisciplinary task force developed guidelines for practitioners.

RESULTS

A team approach (endocrinologist, dietitian, surgeon, psychologist) is recommended. Appropriate candidates have a history of RYGB, severe hypoglycemia refractory to medical-nutrition therapy, and significantly affected quality of life. Preoperative requirements include education and expectation setting, determination of initial enteral feeding program, and establishing service with a home enteral provider. Close postoperative follow-up is needed to ensure success and may require adjustments in formula and mode/rate of delivery to optimize tolerance and meet nutritional goals. G-tube nutrition must fully replace oral nutrition to prevent hypoglycemia.

CONCLUSIONS

G-tube placement in the remnant stomach represents a relatively well-tolerated and effective treatment for severe, refractory hypoglycemia after RYGB.

Counterregulatory responses to postprandial hypoglycemia after Roux-en-Y gastric bypass

BACKGROUND

Postbariatric hypoglycemia (PBH) is a potentially serious complication after Roux-en-Y gastric bypass (RYGB), and impaired counterregulatory hormone responses have been suggested to contribute to the condition.

OBJECTIVES

We evaluated counterregulatory responses during postprandial hypoglycemia in individuals with PBH who underwent RYGB.

SETTING

University hospital.

METHODS

Eleven women with documented PBH who had RYGB underwent a baseline liquid mixed meal test (MMT) followed by 5 MMTs preceded by treatment with (1) acarbose 50 mg, (2) sitagliptin 100 mg, (3) verapamil 120 mg, (4) liraglutide 1.2 mg, and (5) pasireotide 300 μg. Blood was collected at fixed time intervals. Plasma and serum were analyzed for glucose, insulin, glucagon, epinephrine, norepinephrine, pancreatic polypeptide (PP), and cortisol.

RESULTS

During the baseline MMT, participants had nadir blood glucose concentrations of 3.3 ± .2 mmol/L. At the time of nadir glucose, there was a small but significant increase in plasma glucagon. Plasma epinephrine concentrations were not increased at nadir glucose but were significantly elevated by the end of the MMT. There were no changes in norepinephrine, PP, and cortisol concentrations in response to hypoglycemia. After treatment with sitagliptin, 8 individuals had glucose nadirs <3.2 mmol/L (versus 4 individuals at baseline), and significant increases in glucagon, PP, and cortisol responses were observed.

CONCLUSIONS

In response to postprandial hypoglycemia, individuals with PBH who underwent RYGB only had minor increases in counterregulatory hormones, while larger hormone responses occurred when glucose levels were lowered during treatment with sitagliptin. The glycemic threshold for counterregulatory activation could be altered in individuals with PBH, possibly explained by recurrent hypoglycemia.

Safety, efficacy and pharmacokinetics of repeat subcutaneous dosing of avexitide (exendin 9-39) for treatment of post-bariatric hypoglycaemia

AIM

To evaluate the safety, efficacy and pharmacokinetics of repeat dosing of two formulations of subcutaneous (SC) avexitide (exendin 9-39) in patients with post-bariatric hypoglycaemia (PBH).

METHODS

In this phase 2, multiple-ascending-dose study conducted at Stanford University, 19 women with PBH underwent a baseline oral glucose tolerance test (OGTT), with metabolic and symptomatic assessments. Fourteen were then sequentially assigned to receive one of four ascending-dose levels of twice-daily lyophilized (Lyo) avexitide by SC injection for 3 days. On the basis of safety, efficacy and tolerability, five additional participants then received a novel liquid formulation (Liq) of avexitide by SC injection at a fixed dose of 30 mg twice daily for 3 days. All 19 participants underwent a repeat OGTT on day 3 of dosing to quantify metabolic, symptomatic and pharmacokinetic responses.

RESULTS

Treatment with Lyo avexitide reduced the magnitude of symptomatic hyperinsulinaemic hypoglycaemia at all dose levels, with dose-dependent improvements in glucose nadir, insulin peak and symptom score; doses ≥20 mg twice daily did not require glycaemic rescue (administered at glucose <2.8 mmol/L). Participants receiving Liq avexitide 30 mg twice daily did not require any glycaemic rescue, and on average achieved a 47% increase in glucose nadir, a 67% reduction in peak insulin, and a 47% reduction in overall symptom score. Equivalent doses of Liq versus Lyo avexitide yielded higher and more sustained plasma concentrations. Both formulations were well tolerated.

CONCLUSIONS

In patients with PBH, twice-daily administration of SC avexitide effectively raised the glucose nadir and prevented severe hypoglycaemia requiring rescue intervention. Avexitide may represent a viable therapy for PBH.

A Potential Role for Endogenous Glucagon in Preventing Post-Bariatric Hypoglycemia

Obesity and obesity-related diseases are major public health concerns that have been exponentially growing in the last decades. Bariatric surgery is an effective long-term treatment to achieve weight loss and obesity comorbidity remission. Post-bariatric hypoglycemia (PBH) is a late complication of bariatric surgery most commonly reported after Roux-en-Y gastric bypass (RYGB). PBH is the end result of postprandial hyperinsulinemia but additional endocrine mechanisms involved are still under debate. Our aim was to characterize entero-pancreatic hormone dynamics associated with postprandial hypoglycemia after RYGB. Individuals previously submitted to RYGB (N=23) in a single tertiary hospital presenting PBH symptoms (Sym, n=14) and asymptomatic weight-matched controls (Asy, n=9) were enrolled. Participants underwent a mixed-meal tolerance test (MMTT) to assess glucose, total amino acids (total AA), insulin, C-peptide, glucagon, glucose-dependent insulinotropic polypeptide (GIP), glucagon-like peptide-1 (GLP-1), and neurotensin (NT). We found that hypoglycemia during the MMTT was equally frequent in Sym and Asy groups (p=1.000). Re-grouped according to glucose nadir during the MMTT (Hypo n=11 vs NoHypo n=12; nadir <3.05 mmol/l vs ≥3.05 mmol/l), subjects presented no differences in anthropometric (BMI: p=0.527) or metabolic features (HbA_1c: p=0.358), yet distinct meal-elicited hormone dynamics were identified. Postprandial glucose excursion and peak glucose levels were similar (p>0.05), despite distinct late glycemic outcomes (t=60 min and t=90 min: p<0.01), with overall greater glycemic variability in Hypo group (minimum-to-maximum glucose ratio: p<0.001). Hypo group meal-triggered hormone profile was characterized by lower early glucagon (t=15 min: p<0.01) and higher insulin (t=30 min: p<0.05, t=45 min: p<0.001), C-peptide (t=30 min: p<0.01, t=45 min: p<0.001, t=60 min: p<0.05), and GLP-1 (t=45 min: p<0.05) levels. Hyperinsulinemia was an independent risk factor for hypoglycemia (p<0.05). After adjusting for hyperinsulinemia, early glucagon correlated with glycemic nadir (p<0.01), and prevented postprandial hypoglycemia (p<0.05). A higher insulin to glucagon balance in Hypo was observed (p<0.05). No differences were observed in total AA, GIP or NT excursions (p>0.05). In sum, after RYGB, postprandial hyperinsulinemia is key in triggering PBH, but a parallel and earlier rise in endogenous glucagon might sustain the inter-individual variability in glycemic outcome beyond the effect of hyperinsulinism, advocating a potential pivotal role for glucagon in preventing hyperinsulinemic hypoglycemia.