Report from the 1st Cardiovascular Outcome Trial (CVOT) Summit of the Diabetes & Cardiovascular Disease (D&CVD) EASD Study Group

CVOT Summit Report 2023: new cardiovascular, kidney, and metabolic outcomes

The 9th Cardiovascular Outcome Trial (CVOT) Summit: Congress on Cardiovascular, Kidney, and Metabolic Outcomes was held virtually on November 30-December 1, 2023. This reference congress served as a platform for in-depth discussions and exchange on recently completed outcomes trials including dapagliflozin (DAPA-MI), semaglutide (SELECT and STEP-HFpEF) and bempedoic acid (CLEAR Outcomes), and the advances they represent in reducing the risk of major adverse cardiovascular events (MACE), improving metabolic outcomes, and treating obesity-related heart failure with preserved ejection fraction (HFpEF). A broad audience of endocrinologists, diabetologists, cardiologists, nephrologists and primary care physicians participated in online discussions on guideline updates for the management of cardiovascular disease (CVD) in diabetes, heart failure (HF) and chronic kidney disease (CKD); advances in the management of type 1 diabetes (T1D) and its comorbidities; advances in the management of CKD with SGLT2 inhibitors and non-steroidal mineralocorticoid receptor antagonists (nsMRAs); and advances in the treatment of obesity with GLP-1 and dual GIP/GLP-1 receptor agonists. The association of diabetes and obesity with nonalcoholic steatohepatitis (NASH; metabolic dysfunction-associated steatohepatitis, MASH) and cancer and possible treatments for these complications were also explored. It is generally assumed that treatment of chronic diseases is equally effective for all patients. However, as discussed at the Summit, this assumption may not be true. Therefore, it is important to enroll patients from diverse racial and ethnic groups in clinical trials and to analyze patient-reported outcomes to assess treatment efficacy, and to develop innovative approaches to tailor medications to those who benefit most with minimal side effects. Other keys to a successful management of diabetes and comorbidities, including dementia, entail the use of continuous glucose monitoring (CGM) technology and the implementation of appropriate patient-physician communication strategies. The 10th Cardiovascular Outcome Trial Summit will be held virtually on December 5-6, 2024 ( http://www.cvot.org ).

Absolute treatment effects of novel antidiabetic drugs on a composite renal outcome: meta-analysis of digitalized individual patient data

BACKGROUND

Absolute treatment benefits-expressed as numbers needed to treat-of the glucose lowering and cardiovascular drugs, glucagon-like peptide-1 (GLP-1) receptor agonists and sodium-glucose transporter 2 (SGLT2) inhibitors on renal outcomes remain uncertain. With the present meta-analysis of digitalized individual patient data, we aimed to display and compare numbers needed to treat of both drugs on a composite renal outcome.

METHODS

From Kaplan-Meier plots of major cardiovascular outcome trials of GLP-1 receptor agonists and SGLT2 inhibitors vs. placebo, we digitalized individual patient time-to-event information on composite renal outcomes with WebPlotDigitizer 4.2; numbers needed to treat from individual cardiovascular outcome trials were estimated using parametric Weibull regression models and compared to original data. Random-effects meta-analysis generated meta-numbers needed to treat with 95% confidence intervals (CI).

RESULTS

Twelve cardiovascular outcome trials (three for GLP-1 receptor agonists, nine for SGLT2 inhibitors) comprising 90,865 participants were included. Eight trials were conducted in primary type 2 diabetes populations, two in a primary heart failure and two in a primary chronic kidney disease population. Mean estimated glomerular filtration rate at baseline ranged between 37.3 and 85.3 ml/min/1.73 m2. Meta-analyses estimated meta-numbers needed to treat of 85 (95% CI 60; 145) for GLP-1 receptor agonists and 104 (95% CI 81; 147) for SGLT2 inhibitors for the composite renal outcome at the overall median follow-up time of 36 months.

CONCLUSION

The present meta-analysis of digitalized individual patient data revealed moderate and similar absolute treatment benefits of GLP-1 receptor agonists and SGLT2 inhibitors compared to placebo for a composite renal outcome.

CVOT Summit 2022 Report: new cardiovascular, kidney, and glycemic outcomes

The 8th Cardiovascular Outcome Trial (CVOT) Summit on Cardiovascular, Kidney, and Glycemic Outcomes was held virtually on November 10-12, 2022. Following the tradition of previous summits, this reference congress served as a platform for in-depth discussion and exchange on recently completed outcomes trials as well as key trials important to the cardiovascular (CV) field. This year's focus was on the results of the DELIVER, EMPA-KIDNEY and SURMOUNT-1 trials and their implications for the treatment of heart failure (HF) and chronic kidney disease (CKD) with sodium-glucose cotransporter-2 (SGLT2) inhibitors and obesity with glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) receptor agonists. A broad audience of primary care physicians, diabetologists, endocrinologists, cardiologists, and nephrologists participated online in discussions on new consensus recommendations and guideline updates on type 2 diabetes (T2D) and CKD management, overcoming clinical inertia, glycemic markers, continuous glucose monitoring (CGM), novel insulin preparations, combination therapy, and reclassification of T2D. The impact of cardiovascular outcomes on the design of non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) trials, as well as the impact of real-world evidence (RWE) studies on the confirmation of CVOT outcomes and clinical trial design, were also intensively discussed. The 9th Cardiovascular Outcome Trial Summit will be held virtually on November 23-24, 2023 ( http://www.cvot.org ).

Fragility of cardiovascular outcome trials (CVOTs) examining nutrition interventions among patients with diabetes mellitus: a systematic review of randomized controlled trials

PURPOSE

There is controversy regarding the optimal statistical method to interpret how robust is a statistically significant result. The fragility index (FI) and the reverse fragility index (RFI) are quantitative measures that can facilitate the appraisal of a clinical trial's robustness. This study was performed to evaluate the FI and RFI of randomized controlled trials (RCTs) examining nutritional interventions in patients with diabetes mellitus, focusing on cardiovascular outcomes.

METHODS

A systematic search was conducted and relevant RCTs were identified in three databases. RCTs examining nutritional interventions (supplements or dietary patterns) in patients with DM with dichotomous primary endpoints involving cardiovascular outcomes were eligible. Data were extracted to compose 2 × 2 event tables and the FI and RFI were calculated for each comparison, using Fisher's exact test. Risk of bias (RoB) of the included RCTs was assessed with the Cochrane RoB 2.0 tool.

RESULTS

A total of 14,315 records were screened and 10 RCTs were included in the analyses. The median FI of the paired comparisons was 3 (IQR: 2-4) and the median RFI was 8 (IQR: 4.5-17). RoB and heterogeneity were low.

CONCLUSIONS

RCTs examining nutritional interventions and cardiovascular outcomes among patients with diabetes mellitus appear to be statistically fragile. Τhe FI and the RFI can be reported and interpreted as an additional perspective of a trial's robustness.

HIGHLIGHTS

• In the evidence-healthcare era, assessing how robust statistically significant results are remains a matter of controversy. • Recently, the fragility index (FI) and reverse fragility index (RFI) were proposed to assess the robustness of randomized controlled trials (RCTs) with 2 × 2 comparisons. • When applying the FI and RFI, RCTs examining nutritional interventions and cardiovascular outcomes among patients with diabetes mellitus (DM) appear to be statistically fragile. • Τhe FI and the RFI can be reported and interpreted as an additional perspective of a trial's robustness. • RCTs implementing nutrition interventions among patients with DM can improve their methodology.

Report from the CVOT Summit 2021: new cardiovascular, renal, and glycemic outcomes

The 7th Cardiovascular Outcome Trial (CVOT) Summit on Cardiovascular, Renal, and Glycemic Outcomes, was held virtually on November 18–19, 2021. Pursuing the tradition of the previous summits, this reference congress served as a platform for in-depth discussion and exchange on recently completed CVOTs. This year’s focus was placed on the outcomes of EMPEROR-Preserved, FIGARO-DKD, AMPLITUDE-O, SURPASS 1–5, and STEP 1–5. Trial implications for diabetes and obesity management and the impact on new treatment algorithms were highlighted for endocrinologists, diabetologists, cardiologists, nephrologists, and general practitioners. Discussions evolved from outcome trials using SGLT2 inhibitors as therapy for heart failure, to CVOTs with nonsteroidal mineralocorticoid receptor antagonists and GLP-1 receptor agonists. Furthermore, trials for glycemic and overweight/obesity management, challenges in diabetes management in COVID-19, and novel guidelines and treatment strategies were discussed.

Trial registration The 8th Cardiovascular Outcome Trial Summit will be held virtually on November 10–11, 2022 (http://www.cvot.org)

The effect of sodium-glucose transport protein 2 inhibitors on mortality and heart failure in randomized trials versus observational studies

AIM

Randomized clinical trials (RCTs) allocating type 2 diabetes patients to treatment with sodium-glucose transport protein 2 (SGLT-2) inhibitors or placebo have found significant effects on the risk of heart failure and modest effects on mortality. In the wake of the first trials, a number of observational studies have been conducted, some of these reporting a mortality reduction of 50% compared to active comparators. In this review, we systematically assess and compare the results on all-cause mortality, cardiovascular mortality and heart failure hospitalization observed in RCTs with the results obtained in observational studies.

METHOD

We performed a systematic bibliographical search including cardiovascular outcome trials and observational studies assessing the effect of SGLT-2 inhibitors on mortality and heart failure.

RESULTS

Seven RCTs and 23 observational studies were included in the current review. The observed heterogeneity between study results for all-cause mortality (p-interaction < 0.001) and cardiovascular mortality (p-interaction < 0.001) was explained by study type, whereas this was not the case for heart failure (p-interaction = 0.18).

CONCLUSION

Methodological considerations such as the omission of important confounders, immortal-time bias and residual confounding such as unmeasured social economic inequality may be the cause of the inflated results observed in observational studies and that calls for caution when observational studies are used to guide treatment of patients with type 2 diabetes.

Electrical Features of the Diabetic Myocardium. Arrhythmic and Cardiovascular Safety Considerations in Diabetes

Diabetes is a chronic metabolic disease characterized by hyperglycemia in the absence of treatment. Among the diabetes-associated complications, cardiovascular disease is the major cause of mortality and morbidity in diabetic patients. Diabetes causes a complex myocardial dysfunction, referred as diabetic cardiomyopathy, which even in the absence of other cardiac risk factors results in abnormal diastolic and systolic function. Besides mechanical abnormalities, altered electrical function is another major feature of the diabetic myocardium. Both type 1 and type 2 diabetic patients often show cardiac electrical remodeling, mainly a prolonged ventricular repolarization visible in the electrocardiogram as a lengthening of the QT interval duration. The underlying mechanisms at the cellular level involve alterations on the expression and activity of several cardiac ion channels and their associated regulatory proteins. Consequent changes in sodium, calcium and potassium currents collectively lead to a delay in repolarization that can increase the risk of developing life-threatening ventricular arrhythmias and sudden death. QT duration correlates strongly with the risk of developing torsade de pointes, a form of ventricular tachycardia that can degenerate into ventricular fibrillation. Therefore, QT prolongation is a qualitative marker of proarrhythmic risk, and analysis of ventricular repolarization is therefore required for the approval of new drugs. To that end, the Thorough QT/QTc analysis evaluates QT interval prolongation to assess potential proarrhythmic effects. In addition, since diabetic patients have a higher risk to die from cardiovascular causes than individuals without diabetes, cardiovascular safety of the new antidiabetic drugs must be carefully evaluated in type 2 diabetic patients. These cardiovascular outcome trials reveal that some glucose-lowering drugs actually reduce cardiovascular risk. The mechanism of cardioprotection might involve a reduction of the risk of developing arrhythmia.

Report from the CVOT Summit 2020: new cardiovascular and renal outcomes

The 6th Cardiovascular Outcome Trial (CVOT) Summit “Cardiovascular and Renal Outcomes 2020” was the first to be held virtually on October 29–30, 2020. As in previous years, this summit served as reference meeting for in-depth discussions on the topic of recently completed and presented major outcome trials. This year, focus was placed on the outcomes of VERTIS-CV, EMPEROR-Reduced, DAPA-CKD, and FIDELIO-DKD. Trial implications for diabetes management and the impact on new treatment algorithms were highlighted for diabetologists, cardiologists, endocrinologists, nephrologists, and general practitioners. Discussion evolved from major outcome trials using SGLT-2 inhibitors for treatment and prevention of heart failure and chronic kidney disease in people with and without diabetes, to additional therapy options for chronic kidney disease with a novel mineralocorticoid receptor antagonist. Furthermore, challenges in diabetes management like COVID-19 and obesity, as well as novel treatment strategies and guidelines, were discussed.

The 7th Cardiovascular Outcome Trial Summit will be held virtually on November, 18–19, 2021 (http://www.cvot.org).

A novel oral glucagon-like peptide 1 receptor agonist protects against diabetic cardiomyopathy via alleviating cardiac lipotoxicity induced mitochondria dysfunction

Diabetic cardiomyopathy is one of the major cardiovascular complications of diabetes mellitus associated with left ventricular diastolic dysfunction. There are still no specific therapeutic guidelines for the disease. In recent years, glucagon-like peptide 1 receptor agonists were proved to exert cardioprotective effects in comprehensive studies. Therefore, we examined whether a novel oral availably glucagon-like peptide 1 receptor agonist, oral hypoglycemic peptide 2 (OHP2), could protect against diabetic cardiomyopathy in high-fat diets and continuous streptozocin injection induced rat models. After treatment for eight weeks, heart function was evaluated by echocardiography. As expected, OHP2 improved cardiac structure and function beyond glycemic control. Both hyperlipidemia and myocardium lipid accumulation were decreased by OHP2 treatment. In addition, OHP2 reversed oxidative stress and mitochondrial dysfunction in diabetic hearts. In vitro study suggested that OHP2 prevented palmitic acid-induced oxidative stress and mitochondrial dysfunction via suppressing intercellular lipid accumulation. Hence, our present findings pointed out that OHP2 is a promising oral glucagon-like peptide 1 receptor agonist for preventing diabetic cardiomyopathy.

Report from the 5th cardiovascular outcome trial (CVOT) summit

The 5th Cardiovascular Outcome Trial (CVOT) Summit was held in Munich on October 24th-25th, 2019. As in previous years, this summit served as a reference meeting for in-depth discussions on the topic of recently completed and presented CVOTs. This year, focus was placed on the CVOTs CAROLINA, CREDENCE, DAPA-HF, REWIND, and PIONEER-6. Trial implications for diabetes management and the impact on new treatment algorithms were highlighted for diabetologists, cardiologists, endocrinologists, nephrologists, and general practitioners. Discussions evolved from CVOTs to additional therapy options for heart failure (ARNI), knowledge gained for the treatment and prevention of heart failure and diabetic kidney disease in populations with and without diabetes, particularly using SGLT-2 inhibitors and GLP-1 receptor agonists. Furthermore, the ever increasing impact of CVOTs and substances tested for primary prevention and primary care was discussed. The 6th Cardiovascular Outcome Trial Summit will be held in Munich on October 29th-30th, 2020 (https://www.cvot.org).

Report from the 4th Cardiovascular Outcome Trial (CVOT) Summit of the Diabetes & Cardiovascular Disease (D&CVD) EASD Study Group

The 4th Cardiovascular Outcome Trial (CVOT) Summit of the Diabetes & Cardiovascular Disease (D&CVD) EASD Study Group was held in Munich on 25–26 October 2018. As in previous years, this summit served as a reference meeting for in-depth discussions on the topic of recently completed and presented CVOTs. This year, focus was placed on the CVOTs CARMELINA, DECLARE-TIMI 58 and Harmony Outcomes. Trial implications for diabetes management and the impact of the new ADA/EASD consensus statement treatment algorithm were highlighted for diabetologists, cardiologists, endocrinologists, nephrologists and general practitioners. Discussions evolved from CVOTs to additional therapy options for heart failure (ARNI), knowledge gained for adjunct therapy of type 1 diabetes and, on the occasion of the 10 year anniversary of the FDA’s “Guidance for Industry: “should CVOTs be continued and/or modified?” The 5th Cardiovascular Outcome Trial Summit will be held in Munich on 24–25 October 2019 (http://www.cvot.org).

Should Metformin Remain First-Line Medical Therapy for Patients with Type 2 Diabetes Mellitus and Atherosclerotic Cardiovascular Disease? An Alternative Approach

PURPOSE OF REVIEW

With recent cardiovascular outcome trial (CVOT) results for antihyperglycemic medications, the treatment algorithm for patients with type 2 diabetes (T2DM) and atherosclerotic vascular disease (ASCVD) requires revision.

RECENT FINDINGS

All completed CVOTs have demonstrated CV safety of the tested medications, with some trials demonstrating CV efficacy. While metformin remains the first-line recommended medication for T2DM, 18-37% of the patients enrolled in the completed CVOTs were not treated with metformin, providing substantial power to assess CV outcomes independent of metformin. The safety and tolerability of metformin are indisputable, but there are no robust data proving its efficacy for either macro or microvascular disease outcomes. We should reconsider the primacy of metformin in the management of T2DM in patients with ASCVD. This article will review the evidence for CV effects of antihyperglycemic agents (AHAs), and propose an evidence-based treatment algorithm for patients with T2DM and ASCVD.

Report from the 3rd Cardiovascular Outcome Trial (CVOT) Summit of the Diabetes & Cardiovascular Disease (D&CVD) EASD Study Group

The 3rd Cardiovascular Outcome Trial Summit of the Diabetes & Cardiovascular Disease EASD Study Group was held on the 26-27 October 2017 in Munich. As in 2015 and 2016, this summit was organised in light of recently completed and published CVOTs on diabetes, aiming to serve as a reference meeting for in-depth discussions on the topic. Amongst others, the CVOTs EXSCEL, DEVOTE, the CANVAS program and the ACE-trial, which released primary outcome results in 2017, were discussed. Trial implications for diabetes management and recent perspectives of diabetologists, cardiologists, endocrinologists, nephrologists and general practitioners were highlighted. The clinical relevance of cardiovascular outcome trials and its implications regarding reimbursement were compared with real-world studies. The 4th Cardiovascular Outcome Trial Summit will be held in Munich 25-26 October 2018 ( http://www.dcvd.org ).

Teneligliptin enhances the beneficial effects of GLP-1 in endothelial cells exposed to hyperglycemic conditions

High-glucose-induced oxidative stress contributes to cardiovascular endothelial damage in diabetes. Glucagon-like peptide 1 (GLP-1) is beneficial to endothelial cells, but its effects are diminished when cells are continuously exposed to high glucose. Teneligliptin is a dipeptidyl peptidase-4 (DPP-4) inhibitor that prevents oxidative stress, apoptosis and the metabolic memory effect. We explored the potential additive effects of Teneligliptin and GLP-1 in hyperglycemia-damaged endothelial cells. Human umbilical vein endothelial cells (HUVECs) were exposed to normal-glucose (5 mmol/L) or high-glucose (HG, 25 mmol/L) for 21 days, or to HG for 14 days followed by normal-glucose for 7 days (HM). These cells were continually treated with Teneligliptin 3.0 μmol/L, alone or in combination with an acute dose of GLP-1 50 nmol/L. DPP-4 was upregulated under hyperglycemic conditions, but Teneligliptin reduced DPP-4 expression and activity. Simultaneous Teneligliptin and GLP-1 synergistically increased the antioxidant response and reduced ROS levels in HG- and HM-exposed HUVECs. Concurrent treatment also enhanced cell proliferation, reduced apoptotic gene expression and ameliorated endoplasmic reticulum stress in HG- and HM-exposed HUVECs. Thus, long-term Teneligliptin treatment reduced DPP-4 levels and activity in HUVECs exposed to chronic hyperglycemia. Moreover, Teneligliptin enhanced the beneficial effects of GLP-1 on oxidative stress, proliferation, apoptosis and endoplasmic reticulum homeostasis.

A review of glucagon-like peptide-1 receptor agonists and their effects on lowering postprandial plasma glucose and cardiovascular outcomes in the treatment of type 2 diabetes mellitus

Type 2 diabetes mellitus (T2DM) is an independent risk factor for cardiovascular (CV) comorbidities, with CV disease being the most common cause of death in adults with T2DM. Although glucocentric therapies may improve glycaemic control (as determined by glycated haemoglobin levels), evidence suggests that this approach alone has limited beneficial effects on CV outcomes relative to improvements in lipid and blood pressure control. This may be explained in part by the fact that current antidiabetic treatment regimens primarily address overall glycaemia and/or fasting plasma glucose, but not the postprandial plasma glucose (PPG) excursions that have a fundamental causative role in increasing CV risk. This literature review evaluates the relationship between PPG and the risk of CV disease, discusses the treatment of T2DM with glucagon-like peptide-1 receptor agonists (GLP-1 RAs) and examines the associated CV outcomes. The literature analysis suggests that exaggerated PPG excursions are a risk factor for CV disease because of their adverse pathophysiologic effects on the vasculature, resulting in increased all-cause and CV-related mortality. Although GLP-1 RAs are well established in the current T2DM treatment paradigm, a subgroup of these compounds has a particularly pronounced, persistent and short-lived effect on gastric emptying and, hence, lower PPG substantially. However, current long-term data on CV outcomes with GLP-1 RAs are contradictory, with both beneficial and adverse effects having been reported. This review explores the opportunity to direct treatment towards controlling PPG excursions, thereby improving not only overall glycaemic control but also CV outcomes.

Dose Modification of Antidiabetic Agents in Patients with Type 2 Diabetes Mellitus and Heart Failure

Heart failure is the most common comorbidity of diabetes. The incidence of heart failure in patients with diabetes is about 9%-22%, which is four times higher Than that in patients without diabetes. Heart failure and diabetes are collectively associated with increased morbidity and mortality compared to either condition alone. Several epidemiological studies have demonstrated an increased risk of heart failure in patients with diabetes; moreover, poor glycemic control accounts for the increased risk of heart failure. At present, several oral (metformin, sulfonylureas, thiazolidinediones, dipeptidyl peptidase-4 inhibitors, etc.) as well as injectable (insulins, glucagon-like peptide 1 receptor agonists) antidiabetic agents are available. However, optimal treatment strategy to achieve adequate glycemic control in patients with type 2 diabetes mellitus (T2DM) and heart failure has not been well studied. In the view of rising prevalence of heart failure in patients with diabetes mellitus, clinicians need to understand the potential implications of antidiabetic agents in patients with heart failure. A group of experts from across India were involved in a consensus meeting in Pondicherry during the National Insulin Summit in November 2015. They evaluated agents currently available for the treatment of diabetes looking at existing scientific evidence relevant to each class of therapy. In addition, the existing guidelines and prescribing literature available with all these agents were also reviewed. Findings from the expert evaluations were then factored into the national context incorporating personal experience and common clinical practices in India. The purpose of this consensus document is to assist the clinicians while treating patients with T2DM and heart failure.

Incretin-based agents in type 2 diabetic patients at cardiovascular risk: compare the effect of GLP-1 agonists and DPP-4 inhibitors on cardiovascular and pancreatic outcomes

Background

Incretin-based agents, including dipeptidyl peptidase-4 inhibitors (DPP-4Is) and glucagon-like peptide-1 agonists (GLP-1As), work via GLP-1 receptor for hyperglycemic control directly or indirectly, but have different effect on cardiovascular (CV) outcomes. The present study is to evaluate and compare effects of incretin-based agents on CV and pancreatic outcomes in patients with type 2 diabetes mellitus (T2DM) and high CV risk.

Methods

Six prospective randomized controlled trials (EXMAINE, SAVOR-TIMI53, TECOS, ELIXA, LEADER and SUSTAIN-6), which included three trials for DPP-4Is and three trials for GLP-1As, with 55,248 participants were selected to assess the effect of different categories of incretin-based agents on death, CV outcomes (CV mortality, major adverse CV events, nonfatal myocardial infarction, nonfatal stroke, heart failure hospitalization), pancreatic events (acute pancreatitis and pancreatic cancer) as well as on hypoglycemia.

Results

When we evaluated the combined effect of six trials, the results suggested that incretin-based treatment had no significant effect on overall risks of CV and pancreatic outcomes compared with placebo. However, GLP-1As reduced all-cause death (RR = 0.90, 95% CI 0.82–0.98) and CV mortality (RR = 0.84, 95% CI 0.73–0.97), whereas DPP-4Is had no significant effect on CV outcomes but elevated the risk for acute pancreatitis (OR = 1.76, 95% CI 1.14–2.72) and hypoglycemia (both any and severe hypoglycemia), while GLP-1As lowered the risk of severe hypoglycemia.

Conclusions

GLP-1As decreased risks of all-cause and CV mortality and severe hypoglycemia, whereas DPP-4Is had no effect on CV outcomes but increased risks in acute pancreatitis and hypoglycemia.

Electronic supplementary material

The online version of this article (doi:10.1186/s12933-017-0512-z) contains supplementary material, which is available to authorized users.

Current perspectives on cardiovascular outcome trials in diabetes

Cardiovascular disease (CVD) is one of the most common diabetes-associated complications, as well as a leading cause for death in type 2 diabetes patients (T2D). Despite the well-known correlation between the two, up until the 2008 FDA industry guidance for licensing of new anti-hyperglycemic drugs, which required an investigation of cardiovascular outcomes (CVO) of glucose-lowering agents, only a few studies had looked into the relationship between glucose lowering drugs and cardiovascular (CV) risk. Thereafter, CVOT design has focused on non-inferiority short-term studies on high-risk patient populations aiming at capturing CV safety issues. Despite the wealth of information and useful data provided by CVOTs, this approach still suffers from certain limitations. The present review will condense the main results of the most recently completed CVOTs, reflect on the lessons learned, discuss on the issues presented by current CVOT design and offer some suggestions for improvement.

Glucagon and heart in type 2 diabetes: new perspectives

Increased levels of glucagon in type 2 diabetes are well known and, until now, have been considered deleterious. However, glucagon has an important role in the maintenance of both heart and kidney function. Moreover, in the past, glucagon has been therapeutically used for heart failure treatment. The new antidiabetic drugs, dipeptidyl peptidase-4 inhibitors and sodium-glucose co-transporter-2 inhibitors, are able to decrease and to increase glucagon levels, respectively, while contrasting data have been reported regarding the glucagon like peptide 1 receptors agonists. The cardiovascular outcome trials, requested by the FDA, raised some concerns about the possibility that the dipeptidyl peptidase-4 inhibitors can precipitate the heart failure, while, at least for empagliflozin, a positive effect has been shown in decreasing both cardiovascular death and heart failure. The recent LEADER Trial, showed a significant reduction of cardiovascular death with liraglutide, but a neutral effect on heart failure. A possible explanation of the results with the DPPIV inhibitors and empagliflozin might be related to their divergent effect on glucagon levels. Due to unclear effects of glucagon like peptide 1 receptor agonists on glucagon, the possible role of this hormone in the Leader trial remains unclear.