Refueling the Failing Heart: A Case for Sodium-Glucose Cotransporter 2 Inhibition in Cardiac Energy Homeostasis

SGLT2 inhibitors: Beyond glycemic control

Multiple randomized controlled trials have extensively examined the therapeutic effectiveness of sodium-glucose cotransporter 2 (SGLT2) inhibitors, ushering in a transformative approach to treating individuals with type 2 diabetes mellitus (DM). Notably, emerging reports have drawn attention to the potential positive impacts of SGLT2 inhibitors in nondiabetic patients. In an effort to delve into this phenomenon, a comprehensive systematic literature review spanning PubMed (NLM), Medline (Ovid), and Cochrane Library, covering publications from 2000 to 2024 was undertaken. This systematic review encompassed twenty-six randomized control trials (RCTs) involving 35,317 participants. The findings unveiled a multifaceted role for SGLT2 inhibitors, showcasing their ability to enhance metabolic control and yield cardioprotective effects through a reduction in cardiovascular death (CVD) and hospitalization related to heart failure (HF). Additionally, a renalprotective effect was observed, evidenced by a slowdown in chronic kidney disease (CKD) progression and a decrease in albuminuria. Importantly, these benefits were coupled with an acceptable safety profile. The literature also points to various biological plausibility and underlying mechanistic pathways, offering insights into the association between SGLT2 inhibitors and these positive outcomes in nondiabetic individuals. Current research trends indicate a continual exploration of additional role for SGLT2 inhibitors in. Nevertheless, further research is imperative to fully elucidate the mechanisms and long-term outcomes associated with the nondiabetic use of SGLT2 inhibitors.

Promise of sodium-glucose co-transporter-2 inhibitors in heart failure with mildly reduced ejection fraction

Heart failure with mildly reduced ejection fraction (HFmrEF) is associated with comparable poor outcomes as other subtypes of heart failure and remains a medical unmet need due to the paucity of effective therapies. According to large cardiovascular (CV) outcome trials in patients with heart failure, sodium-glucose co-transporter-2 inhibitors (SGLT2is) reduce CV mortality and hospitalizations for heart failure in patients with heart failure across the spectrum of left ventricular ejection fraction (LVEF). There has been a lack of dedicated trials in HFmrEF. However, several large outcome trials in heart failure that enrolled patients with HFmrEF could provide a hint on the role of SGLT2is in this subgroup. This review focuses on CV effects of three major SGLT2is-dapagliflozin, empagliflozin, and sotagliflozin-in patients with HFmrEF. A narrative review of trials investigating the efficacy of each medication in treating heart failure with LVEF > 40% is provided with a focus on their LVEF subgroup analyses. The purpose of this review is to discuss the current state of evidence regarding the potential of SGLT2is in HFmrEF management. Current limited evidence suggests that SGLT2is might be a favourable treatment modality for patients with HFmrEF to reduce hospitalization for heart failure and CV mortality. This conclusion needs to be further supported by clear HFmrEF subgroup analysis of the existing trials. Further outcome trials involving sufficient patients with different subtypes of HFmrEF are needed to confirm and assess CV benefits of SGLT2is in HFmrEF. Possible mechanisms by which SGLT2is exert their cardioprotective effect are also described briefly.

Sodium-Glucose Co-Transporter 2 (SGLT2) Inhibitors: Are They All the Same? A Narrative Review of Cardiovascular Outcome Trials

Clinically important improvements in cardiovascular risk factors and adverse cardiovascular, heart failure and renal outcomes have been observed in numerous cardiovascular outcome trials (CVOTs) investigating the use of sodium-glucose co-transporter 2 (SGLT2) inhibitors over the last 5 years. However, differences in study outcomes between the various SGLT2 inhibitor CVOTs are often challenging to interpret because of differences in the study design, participant characteristics and primary outcomes of the various trials. In clinical practice, this frequently challenges the clinician when choosing between the different SGLT2 inhibitors for a patient with type 2 diabetes and various cardiovascular or renal comorbidities. Discussion around the choice of SGLT2 inhibitor has been again revived by the recent publication of results from the VERTIS-CV, EMPEROR-reduced and DAPA-CKD trials investigating cardiovascular, heart failure and renal outcomes associated with various SGLT2 inhibitors.This narrative review gives an overview of the mechanism of action and differences in the underlying pharmacology of the various SGLT2 inhibitors and discusses the key cardiovascular, heart failure and renal outcomes from completed CVOTs for SGLT2 inhibitors. Discussion highlights important differences in the study design and participant characteristics which limit the comparison of trials and medications within this drug class.

Are SGLT-2 Inhibitors the Future of Heart Failure Treatment? The EMPEROR-Preserved and EMPEROR-Reduced Trials

Heart failure is frequently associated with diabetes, and therapies which reduce mortality in people with heart failure and reduced ejection fraction (HFrEF) are often limited to drugs which modulate the renin-angiotensin-aldosterone system or heart rate control and occasionally to device therapy. Treatment is even more challenging in people with heart failure and preserved ejection fraction (HFpEF), with currently no approved therapy demonstrating a mortality-improving effect, limiting treatment to diuretics for the alleviation of the symptoms of fluid overload and risk factor management. Previous cardiovascular outcome trials for sodium-glucose co-transporter-2 (SGLT-2) inhibitors have demonstrated significant favourable outcomes for cardiovascular disease, heart failure hospitalisation and all-cause mortality. The aim of the nearly completed EMPEROR-preserved and EMPEROR-reduced trials is to determine the impact of empagliflozin on cardiovascular and heart failure outcomes in people with HFpEF or HFrEF with or without diabetes. The trials will add substantially to our understanding of SGLT-2 inhibitors in the treatment of HFrEF and may have major implications for the treatment of people with HFpEF. The study will also be powered to address the impact of empagliflozin on changes in renal function in people with and without diabetes and incident diabetes in the participants without diabetes at baseline. In this article we discuss the rationale for using SGLT-2 inhibitors in people with heart failure and explore the potential findings and importance of the ongoing EMPEROR-preserved and EMPEROR-reduced trials.

Influence of Sodium Glucose Cotransporter 2 Inhibition on Physiological Adaptation to Endurance Exercise Training

CONTEXT

The combination of two beneficial antidiabetes interventions, regular exercise and pharmaceuticals, is intuitively appealing. However, metformin, the most commonly prescribed diabetes medication, attenuates the favorable physiological adaptations to exercise; in turn, exercise may impede the action of metformin.

OBJECTIVE

We sought to determine the influence of an alternative diabetes treatment, sodium glucose cotransporter 2 (SGLT2) inhibition, on the response to endurance exercise training.

DESIGN, PARTICIPANTS, AND INTERVENTION

In a randomized, double-blind, repeated measures parallel design, 30 sedentary overweight and obese men and women were assigned to 12 weeks of supervised endurance exercise training, with daily ingestion of either a placebo or SGLT2 inhibitor (dapagliflozin: ≤10 mg/day).

OUTCOME MEASUREMENTS AND RESULTS

Endurance exercise training favorably modified body mass, body composition (dual-energy x-ray absorptiometry), peak oxygen uptake (graded exercise with indirect calorimetry), responses to standardized submaximal exercise (indirect calorimetry, heart rate, and blood lactate), and skeletal muscle (vastus lateralis) citrate synthase activity (main effects of exercise training, all P < 0.05); SGLT2 inhibition did not influence any of these physiological adaptations (exercise training × treatment interaction, all P > 0.05). However, after endurance exercise training, fasting blood glucose was greater with SGLT2 inhibition, and increased insulin sensitivity (oral glucose tolerance test/Matsuda index) was abrogated with SGLT2 inhibition (exercise training × treatment interaction, P < 0.01).

CONCLUSION

The efficacy of combining two beneficial antidiabetes interventions, regular endurance exercise and SGLT2 inhibition, was not supported. SGLT2 inhibition blunted endurance exercise training-induced improvements in insulin sensitivity, independent of effects on aerobic fitness or body composition.