Cardiovascular outcomes trials: a paradigm shift in the current management of type 2 diabetes

Cardiovascular disease (CVD) is the leading cause of mortality and morbidity in patients with type 2 diabetes (T2D). Historical concerns about cardiovascular (CV) risks associated with certain glucose-lowering medications gave rise to the introduction of cardiovascular outcomes trials (CVOTs). Initially implemented to help monitor the CV safety of glucose-lowering drugs in patients with T2D, who either had established CVD or were at high risk of CVD, data that emerged from some of these trials started to show benefits. Alongside the anticipated CV safety of many of these agents, evidence for certain sodium-glucose transporter 2 (SGLT2) inhibitors and glucagon-like peptide-1 receptor agonists (GLP-1 RAs) have revealed potential cardioprotective effects in patients with T2D who are at high risk of CVD events. Reductions in 3-point major adverse CV events (3P-MACE) and CV death have been noted in some of these CVOTs, with additional benefits including reduced risks of hospitalisation for heart failure, progression of renal disease, and all-cause mortality. These new data are leading to a paradigm shift in the current management of T2D, with international guidelines now prioritising SGLT2 inhibitors and/or GLP-1 RAs in certain patient populations. However, clinicians are faced with a large volume of CVOT data when seeking to use this evidence base to bring opportunities to improve CV, heart failure and renal outcomes, and even reduce mortality, in their patients with T2D. The aim of this review is to provide an in-depth summary of CVOT data-crystallising the key findings, from safety to efficacy-and to offer a practical perspective for physicians. Finally, we discuss the next steps for the post-CVOT era, with ongoing studies that may further transform clinical practice and improve outcomes for people with T2D, heart failure or renal disease.

Translating results from the cardiovascular outcomes trials with glucagon-like peptide-1 receptor agonists into clinical practice: Recommendations from a Eastern and Southern Europe diabetes expert group

Glucagon-like peptide-1 (GLP-1) receptor agonists mimic the action of the endogenous GLP-1 incretin hormone, improving glycaemic control in type 2 diabetes mellitus (T2DM) by increasing insulin secretion and decreasing glucagon secretion in a glucose-dependent manner. However, as cardiovascular (CV) morbidity and mortality is common in patients with T2DM, several trials with the use of GLP-1 receptor agonists (RAs) have been performed focusing on endpoints related to cardiovascular disease rather than metabolic control of T2DM. Following the positive cardiovascular effects of liraglutide, dulaglutide and semaglutide observed in these trials, major changes in T2DM management guidelines have occurred. This document from a Eastern and Southern European Diabetes Expert Group discusses the results of GLP-1 RA CV outcomes trials, their impact on recent clinical guidelines for the management of T2DM, and some selected combination regimens utilising GLP-1 RAs. We also propose an algorithm for guiding GLP-1 RA-based treatment according to patients' characteristics, which can be easily applied in every day clinical practice.

Glucagon-like Peptide-1 Receptor Agonists and Cardioprotective Benefit in Patients with Type 2 Diabetes Without Baseline Metformin: A Systematic Review and Update Meta-analysis

INTRODUCTION

Sodium Glucose Co-transporter 2 inhibitors and glucagon-like peptide 1 receptor agonists (GLP-1RAs) were associated with a reduction in cardiovascular disease events in cardiovascular outcomes trials (CVOTs) in type 2 diabetes. Most of the patients included in these trials received metformin as background therapy.

AIM

To evaluate the effect of glucagon-like peptide 1 receptor agonists on major cardiovascular events (MACE) and mortality in metformin-naïve patients with type 2 diabetes.

METHODS

A systematic review and meta-analysis of randomized controlled clinical trials of GLP-1RAs on type 2 diabetes population was performed, after searching the PubMed/MEDLINE, Embase, Scielo, Google Scholar and Cochrane Controlled Trials databases. The primary endpoint was MACE. The secondary endpoints were cardiovascular death and all-cause mortality. A meta-analysis of time-to-event outcomes was performed. This meta-analysis was registered in PROSPERO (CRD42021260040) RESULTS: Seven trials, including 11510 patients, were identified and considered eligible for the analyses. GLP-1RAs were associated with a significant reduction in MACE incidence (HR: 0.86, 95% confidence interval: 0.79-0.94; I²: 0%). The secondary endpoints analysis showed a non-significant reduction in all-cause mortality (HR: 0.86, 95% confidence interval: 0.73-1.00 I²: 0%) and cardiovascular mortality (HR: 0.81, 95% confidence interval: 0.63-1.05; I²: 0%).

CONCLUSIONS

In this meta-analysis, GLP-1RAs reduced the incidence of MACE in patients with type 2 diabetes without metformin at baseline, without significant reduction in all-cause mortality and cardiovascular mortality. These results support the fact that when a GLP-1RAs is administered, the benefit on cardiovascular outcomes is independent of the use of metformin.

Sodium-Glucose Co-transporter 2 Inhibitors in the Failing Heart: a Growing Potential

Sodium-glucose co-transporter 2 inhibitors (SGLT2i) are a new drug class designed to treat patients with type 2 diabetes (T2D). However, cardiovascular outcome trials showed that SGLT2i also offer protection against heart failure (HF)-related events and cardiovascular mortality. These benefits appear to be independent of glycaemic control and have recently been demonstrated in the HF population with reduced ejection fraction (HFrEF), with or without T2D. This comprehensive, evidence-based review focuses on the published studies concerning HF outcomes with SGLT2i, discussing issues that may underlie the different results, along with the impact of these new drugs in clinical practice. The potential translational mechanisms behind SGLT2i cardio-renal benefits and the information that ongoing studies may add to the already existing body of evidence are also reviewed. Finally, we focus on practical management issues regarding SGLT2i use in association with other T2D and HFrEF common pharmacological therapies. Safety considerations are also highlighted. Considering the paradigm shift in T2D management, from a focus on glycaemic control to a broader approach on cardiovascular protection and event reduction, including the potential for wide SGLT2i implementation in HF patients, with or without T2D, we are facing a promising time for major changes in the global management of cardiovascular disease.

The Sweet Spot: Heart Failure Prevention with SGLT2 Inhibitors

Sodium-glucose cotransporter 2 (SGLT2) inhibitors are a novel class of medications that reduce plasma glucose concentrations through an insulin-independent mechanism of increased urinary glucose excretion, with concomitant natriuresis and diuresis. Clinical outcomes trials with SGLT2 inhibitors revealed a cardioprotective benefit among patients with diabetes mellitus, with a consistent reduction in hospitalization for heart failure. As such, the 2018 updated US and European treatment guidelines for diabetes mellitus incorporated SGLT2 inhibitors as second-line glucose-lowering agents after metformin. Although well tolerated, there are known adverse effects with SGLT2 inhibitors that require clinical monitoring, such as genital mycotic infections, diabetic ketoacidosis, volume depletion particularly in the setting of concomitant diuretic use, and lower limb amputations with canagliflozin. Ongoing clinical trials will uncover the potential benefit of SGLT2 inhibitors in patients with prevalent heart failure with or without diabetes mellitus.

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.

Hypoglycemia: New Definitions and Regulatory Implications

Hypoglycemia is the limiting factor in controlling glucose levels in Diabetes. Rather than being a side effect, hypoglycemia is the mechanism of action for insulin therapy, with a very narrow therapeutic window. Until recently, regulatory bodies listed hypoglycemia only as an adverse effect of therapy; however, one insulin preparation is now recognized and labelled as reducing the risk of severe hypoglycemia. This paper describes internationally agreed upon definitions for hypoglycemia and proposed regulatory approaches for recognition and labeling of diabetes therapies to facilitate personalized care.