How Do SGLT2 (Sodium-Glucose Cotransporter 2) Inhibitors and GLP-1 (Glucagon-Like Peptide-1) Receptor Agonists Reduce Cardiovascular Outcomes?: Completed and Ongoing Mechanistic Trials

GLP-1RA may have varying effects on cardiac structure in patients with ASCVD depending on BMI

Background

Glucagon-like peptide-1 receptor agonist(GLP-1RA) is commonly used in patients with cardiovascular disease due to its significant improvement in the prognosis of atherosclerotic cardiovascular disease (ASCVD). However, previous studies have primarily focused on obese patients, leaving uncertainty regarding whether GLP-1RA can yield similar cardiovascular benefits in individuals with normal or low body weight.

Methods

In this study, we enrolled patients with ASCVD to establish a retrospective cohort. Patients receiving GLP-1RA treatment were assigned to the GLP-1RA group, while a control group was formed by matching age and body mass index (BMI) among patients not receiving GLP-1RA treatment. Each group was further divided into subgroups based on baseline BMI levels: normal weight, overweight, and obesity. A six-month follow-up was conducted to assess changes in patient weight, metabolic indicators, and cardiac structure and function.

Results

Among the normal weight subgroup, no significant weight change was observed after six months of GLP-1RA treatment (57.4 ± 4.8 vs. 58.7 ± 9.2, p = 0.063). However, significant weight reduction was observed in the other two subgroups (Overweight group: 70.0 ± 9.1 vs. 73.1 ± 8.2, p = 0.003, Obesity group: 90.5 ± 14.3 vs. 95.5 ± 16.6, p<0.001). Regardless of baseline BMI levels, GLP-1RA demonstrated significant glucose-lowering effects in terms of metabolic indicators. However, GLP-1RA have a more significant effect on improving blood lipids in overweight and obese patients. The effects of GLP-1RA on cardiac structure exhibited variations among patients with different baseline BMI levels. Specifically, it was observed that the improvement in atrial structure was more prominent in patients with normal body weight(LAD: 33.0 (30.3, 35.5) vs. 35.0 (32.5, 37.1), p = 0.018, LAA (18.0 (16.0, 21.5) vs. 18.5 (16.5, 20.5), p = 0.008), while the enhancement in ventricular structure was more significant in obese subjects(LEVDD: 49.8 ± 5.8 vs. 50.2 ± 5.0, p < 0.001, LVMI: 65.1 (56.2, 71.4) vs. 65.8 (58.9, 80.4), p < 0.039).

Conclusion

According to the study, it was found that the administration of GLP-1RA can have different effects on cardiac structure in patients with different baseline BMI, In obese patients, improvements in ventricular remodeling may be more associated with weight loss mechanisms, while in patients with normal or low BMI, GLP-1RA may directly improve atrial remodeling through GLP-1 receptors in atrial tissue.

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.

Updates in Cardiovascular Disease Prevention, Diagnosis, and Treatment in Women

Cardiovascular disease (CVD) is the leading cause of death for American women. CVD is preventable although risk reduction goals are not achieved for women compared with men. Considering a woman's cardiometabolic profile for prevention counseling and prescribing may help. Coronary artery calcium scores provide additional risk assessment and reproductive and menopause histories identify risk enhancers. Diagnosis of CVD is often delayed, and treatment is less optimal for women compared with men. Differences in presentation and underlying CVD etiology (Including spontaneous coronary artery dissection and microvascular disease) may partially account for these disparities. Improvements in CVD imaging to better diagnose these etiologies may benefit women's care.

Combination of Empagliflozin and Liraglutide protects heart against isoproterenol-induced myocardial infarction in rats

Cardiovascular benefit of new anti-hyperglycemic agent such as glucagon like peptide-1 receptor agonist (GLP-1RA) or sodium glucose co-transporter-2 inhibitor (SGLT2i) has been proven, with the proposed-mechanism that might be complementary. We investigated the effects of its combination on blood glucose profile and cardiac biomarkers. The rats were given lipid emulsion for 2 weeks, followed by a single dose of streptozotocin (STZ) 35 mg/kg BW, then treated with empagliflozin and/ liraglutide for 30 days while receiving isoproterenol (ISO) 85 mg/kg on day 29 and 30. The results showed no superior improvement on fasting blood glucose (FBG) and insulin sensitivity (KITT) in the combination group compared to empagliflozin/liraglutide group. However, the combination group showed a higher inhibition in almost all biomarkers, specifically against the elevation of CK-MB compared to one of these agents alone. The histopathological examination using H&E staining even showed a minimal inflammation and gap between cardiomyocytes. These findings may indicate the combination of empagliflozin and liraglutide has a better cardiac protection effect.

Effects of diet and antihyperglycemic drugs on erectile dysfunction: A systematic review

BACKGROUND

Erectile dysfunction is recognized as one of the complications of diabetes mellitus. To date, a wide gap of knowledge is present on the efficacy of pharmacological treatments of diabetes mellitus on erectile function, acting not only through metabolic control. Similarly, the effects of different diet regimens on erectile dysfunction are still debated.

OBJECTIVES

We aimed to explore the effects of diet and antihyperglycemic drugs, considering both old and novel therapeutic approaches, on erectile function.

MATERIALS/METHODS

We performed a systematic review, following the PRISMA guidelines. The research was conducted on studies reporting erectile dysfunction assessment in subjects with diabetes and the relationship with diet and antihyperglycemic drugs.

RESULTS

The Mediterranean diet was effective in most studies for the protection of erectile function. Furthermore, antihyperglycemic drugs seem to show an overall protective role on erectile function.

DISCUSSION/CONCLUSION

Although encouraging results are present for all classes of antihyperglycemic drugs, several studies are needed in humans, mainly on acarbose, pioglitazone, dipeptidyl-peptidase-4 inhibitors, and sodium-glucose cotransporter-2 inhibitors.

Advancing a causal role of type 2 diabetes and its components in developing macro- and microvascular complications via genetic studies

The role of diabetes in developing microvascular and macrovascular complications has been subject to extensive research. Despite multiple observational and genetic studies, the causal inference of diabetes (and associated risk factors) on those complications remains incomplete. In this review, we focused on type 2 diabetes, as the major form of diabetes, and investigated the evidence of causality provided by observational and genetic studies. We found that genetic studies based on Mendelian randomization provided consistent evidence of causal inference of type 2 diabetes on macrovascular complications; however, the evidence for causal inference on microvascular complications has been somewhat limited. We also noted high BMI could be causal for several diabetes complications, notable given high BMI is commonly upstream of type 2 diabetes and the recent calls to target weight loss more aggressively. We emphasize the need for further studies to identify type 2 diabetes components that mostly drive the risk of those complications. Even so, the genetic evidence summarized broadly concurs with the need for a multifactorial risk reduction approach in type 2 diabetes, including addressing excess adiposity.

Effects of sodium-glucose co-transporter-2 inhibitors on anthropometric indices and metabolic markers in overweight/obese individuals without diabetes: a systematic review and meta-analysis

AIMS

To identify the impact of sodium-glucose co-transporter-2 (SGLT2) inhibitors on anthropometric indices and metabolic markers in individuals without diabetes who are overweight/obese.

MATERIALS AND METHODS

Clinical trials investigating the safety and efficacy of SGLT2 inhibitors in overweight or obese adults were sought in PubMed, Scopus, Google Scholar, and EMBASE databases. The overall intervention effect was estimated using a random-effect meta-analysis. Jadad scale was used to assess the risk of bias. The heterogeneity of the studies was assessed using the Cochran's test (Q test) and I² Index. Analyses of meta-regression were carried out to identify possible sources of heterogeneity among the trials. The analyses were all conducted using Stata, and p < .05 was set as the statistically significant level.

RESULTS

Of the five clinical trials that were included in the meta-analysis, five, four, three, and two clinical trials met the eligibility criteria for evaluating the efficacy of SGLT2 inhibitors on the weight, waist circumference (WC) and blood pressure, body mass index (BMI), and lipid and glucose profile, respectively. According to the results, SGLT2 inhibitors lowered BMI (WMD = -0.47 [95% CI: -0.63, -0.31]; p < .001), and WC (WMD = -3.25 [95% CI: -6.36, -0.14]; p = .04), but had no significant influence on blood pressure, lipid, and glucose profile of overweight/obese patients compared to the control groups.

CONCLUSION

The SGLT2 inhibitors appear to ameliorate some anthropometric and metabolic markers. There is, however, a limited number of studies, and further research is required for a firm conclusion.

REGISTRATION CODE IN PROSPERO

CRD42022306415.

Cardiovascular outcomes with GLP-1 receptor agonists vs. SGLT-2 inhibitors in patients with type 2 diabetes

AIMS

We examined cardiovascular outcomes associated with initiation of glucagon-like peptide-1 receptor agonist (GLP-1RA) vs. sodium-glucose co-transporter-2 inhibitor (SGLT-2i) treatment in a real-world setting among patients with type 2 diabetes.

METHODS AND RESULTS

This Danish nationwide registry-based cohort study included patients with type 2 diabetes with a first-ever prescription of either GLP-1RA or SGLT-2i from 2013 through 2015 with follow-up until end of 2018. All analyses were standardized with respect to age, sex, diabetes duration, comorbidity, and comedication. The main outcome was a composite of cardiovascular death, myocardial infarction, and stroke. Furthermore, the components of the composite outcome and hospitalization for heart failure were evaluated. Standardized average 3-year risks of outcomes and differences thereof were estimated using doubly robust estimation combining cause-specific Cox regression with propensity score regression. We identified 8913 new users of GLP-1RA and 5275 new users of SGLT-2i. The standardized 3-year risk associated with initiating GLP-1RA and SGLT-2i, respectively, was as follows: composite cardiovascular outcome, 5.6% [95% confidence interval (CI): 5.2-6.1] vs. 5.6% (95% CI: 4.8-6.3); cardiovascular mortality, 1.6% (95% CI: 1.3-1.9) vs. 1.5% (95% CI: 1.1-1.8); hospitalization for heart failure, 1.7% (95% CI: 1.5-2.0) vs. 1.8% (95% CI: 1.2-2.5); myocardial infarction, 2.1% (95% CI: 1.8-2.4) vs. 2.1% (95% CI: 1.5-2.6); and stroke, 2.5% (95% CI: 2.2-2.9) vs. 2.6% (95% CI: 2.2-3.1).

CONCLUSION

In this nationwide study of patients with type 2 diabetes, initiating GLP-1RA vs. SGLT-2i was not found to be associated with significant differences in cardiovascular risk.

Dapagliflozin improves myocardial flow reserve in patients with type 2 diabetes: the DAPAHEART Trial: a preliminary report

Objective

Cardiovascular (CV) outcome trials have shown that in patients with type 2 diabetes (T2D), treatment with sodium-glucose cotransporter-2 inhibitors (SGLT-2i) reduces CV mortality and hospital admission rates for heart failure (HF). However, the mechanisms behind these benefits are not fully understood. This study was performed to investigate the effects of the SGLT-2i dapagliflozin on myocardial perfusion and glucose metabolism in patients with T2D and stable coronary artery disease (coronary stenosis ≥ 30% and < 80%), with or without previous percutaneous coronary intervention (> 6 months) but no HF.

Methods

This was a single-center, prospective, randomized, double-blind, controlled clinical trial including 16 patients with T2D randomized to SGLT-2i dapagliflozin (10 mg daily) or placebo. The primary outcome was to detect changes in myocardial glucose uptake (MGU) from baseline to 4 weeks after treatment initiation by [(18)F]2-deoxy-2-fluoro-D-glucose (FDG) PET/CT during hyperinsulinemic euglycemic clamp. The main secondary outcome was to assess whether the hypothetical changes in MGU were associated with changes in myocardial blood flow (MBF) and myocardial flow reserve (MFR) measured by ¹³N-ammonia PET/CT. The study was registered at eudract.ema.europa.eu (EudraCT No. 2016-003614-27) and ClinicalTrials.gov (NCT 03313752).

Results

16 patients were randomized to dapagliflozin (n = 8) or placebo (n = 8). The groups were well-matched for baseline characteristics (age, diabetes duration, HbA1c, renal and heart function). There was no significant change in MGU during euglycemic hyperinsulinemic clamp in the dapagliflozin group (2.22 ± 0.59 vs 1.92 ± 0.42 μmol/100 g/min, p = 0.41) compared with the placebo group (2.00 ± 0.55 vs 1.60 ± 0.45 μmol/100 g/min, p = 0.5). Dapagliflozin significantly improved MFR (2.56 ± 0.26 vs 3.59 ± 0.35 p = 0.006 compared with the placebo group 2.34 ± 0.21 vs 2.38 ± 0.24 p = 0.81; p_int = 0.001) associated with a reduction in resting MBF corrected for cardiac workload (p = 0.005; p_int = 0.045). A trend toward an increase in stress MBF was also detected (p = 0.054).

Conclusions

SGLT-2 inhibition increases MFR in T2D patients. We provide new insight into SGLT-2i CV benefits, as our data show that patients on SGLT-2i are more resistant to the detrimental effects of obstructive coronary atherosclerosis due to increased MFR, probably caused by an improvement in coronary microvascular dysfunction.

Trial registration EudraCT No. 2016-003614-27; ClinicalTrials.gov Identifier: NCT03313752

Supplementary Information

The online version contains supplementary material available at 10.1186/s12933-022-01607-4.

GLP-1 agonists: superior for mind and body in antipsychotic-treated patients?

Antipsychotics (APDs) represent a core treatment for severe mental disorders (SMEs). Providing symptomatic relief, APDs do not exert therapeutic effects on another clinically significant domain of serious mental disorders, cognitive impairment. Moreover, adverse metabolic effects (diabetes, weight gain, dyslipidemia, and increased cardiovascular risk) are common during treatment with APDs. Among pharmacological candidates reversing APD-induced metabolic adverse effects, glucagon-like peptide-1 (GLP-1) receptor agonists (GLP-1 RAs), approved for both diabetes and recently for obesity treatment, stand out due to their favorable effects on peripheral metabolic parameters. Interestingly, GLP-1 RAs are also proposed to have pro-cognitive effects. Particularly in terms of dual therapeutic mechanisms potentially improving both central nervous system (CNS) deficits and metabolic burden, GLP-1 RAs open a new perspective and assume a clinically advantageous position.

Cardiovascular effects of incretins - focus on GLP-1 receptor agonists

GLP-1 receptor agonists (GLP-1 RAs) have been used to treat patients with type 2 diabetes since 2005 and have become popular because of the efficacy and durability in relation to glycaemic control in combination with weight loss in most patients. Today in 2022, seven GLP-1 RAs, including oral semaglutide are available for treatment of type 2 diabetes. Since the efficacy in relation to reduction of HbA1c and body weight as well as tolerability and dosing frequency vary between agents, the GLP-1 RAs cannot be considered equal. The short acting lixisenatide showed no cardiovascular benefits, while once daily liraglutide and the weekly agonists, subcutaneous semaglutide, dulaglutide, and efpeglenatide, all lowered the incidence of cardiovascular events. Liraglutide, oral semaglutide and exenatide once weekly also reduced mortality. GLP-1 RAs reduce the progression of diabetic kidney disease. In the 2019 consensus report from EASD/ADA, GLP-1 RAs with demonstrated cardio-renal benefits (liraglutide, semaglutide and dulaglutide) are recommended after metformin to patients with established cardiovascular diseases or multiple cardiovascular risk factors. European Society of Cardiology (ESC) suggests starting with a SGLT-2 inhibitor or a GLP-1 RA in drug naïve patients with type 2 diabetes and atherosclerotic CVD or high CV Risk. However, the results from cardiovascular outcome trials (CVOT) are very heterogeneous suggesting that some GLP-1RA are more suitable to prevent CVD than others. The CVOTs provide a basis upon which individual treatment decisions for patients with T2D and CVD can be made.

Impact of sodium-glucose co-transporter inhibitors on cardiac autonomic function and mortality: no time to die

Sodium-glucose co-transporter 2 (SGLT2) inhibitors have been shown to improve cardiovascular outcomes not only in patients with diabetes but also in those with heart failure, irrespective of diabetic status. However, the mechanisms underlying the cardioprotective effects of these newer anti-diabetic drugs remain to be fully elucidated. One exciting avenue that has been recently explored in both preclinical and clinical studies is the modulation of the cardiovascular autonomic nervous system. A reduction in sympathetic nervous system activity by SGLT2 inhibitors may potentially translate into a reduction in arrhythmic risk and sudden arrhythmic death, which may explain, at least partly, the cardioprotection shown in the cardiovascular outcome trials with different SGLT2 inhibitors. Although some of the data from the preclinical and clinical studies are promising, overall the findings can be contradictory. This highlights the need for more studies to address gaps in our knowledge of these novel drugs. The present review offers an in depth overview of the existing literature regarding the role of SGLT2 inhibitors in modulating cardiovascular autonomic function as one of the possible pathways of their cardioprotective effects.

Role of endogenous incretins in the regulation of postprandial lipoprotein metabolism

OBJECTIVE

Incretins are known to influence lipid metabolism in the intestine when administered as pharmacologic agents. The aggregate influence of endogenous incretins on chylomicron production and clearance is less clear, particularly in light of opposing effects of co-secreted hormones. Here, we tested the hypothesis that physiological levels of incretins may impact on production or clearances rates of chylomicrons and VLDL.

DESIGN AND METHODS

A group of 22 overweight/obese men was studied to determine associations between plasma levels of glucagon-like peptides 1 and 2 (GLP-1 and GLP-2) and glucose-dependent insulinotropic polypeptide (GIP) after a fat-rich meal and the production and clearance rates of apoB48- and apoB100-containing triglyceride-rich lipoproteins. Subjects were stratified by above- and below-median incretin response (area under the curve).

RESULTS

Stratification yielded subgroups that differed about two-fold in incretin response. There were neither differences in apoB48 production rates in chylomicrons or VLDL fractions nor in apoB100 or triglyceride kinetics in VLDL between men with above- vs below-median incretin responses. The men with above-median GLP-1 and GLP-2 responses exhibited higher postprandial plasma and chylomicron triglyceride levels, but this could not be related to altered kinetic parameters. No differences were found between incretin response subgroups and particle clearance rates.

CONCLUSION

We found no evidence for a regulatory effect of endogenous incretins on contemporaneous chylomicron or VLDL metabolism following a standardised fat-rich meal. The actions of incretins at pharmacological doses may not be reflected at physiological levels of these hormones.

Efficacy of vildagliptin on 10-year cardiovascular risk reduction in Thai patients with type 2 diabetes mellitus: A real-world observational study

BACKGROUND AND AIMS

This study aimed to assess the effects of vildagliptin on the prevention of cardiovascular diseases in Thai patients with type 2 diabetes mellitus using the Thai Cardiovascular Risk Score.

METHODS

All patients with type 2 diabetes mellitus who used vildagliptin at a secondary hospital in Thailand were screened and recruited. The relevant variables were obtained from patient medication charts at the first visit on which the patients were prescribed vildagliptin and from the 6-month, 12-month, and 18-month post-treatment visits. The Thai Cardiovascular Risk Score was calculated and monitored as a primary outcome, whereas changes in separate cardiometabolic parameters were assessed as secondary outcomes.

RESULTS

Of the 321 patients screened, only 95 were recruited for the analysis. The average 10-year cardiovascular risks of patients increased from 19.65% at baseline to 20.74%, 20.69%, and 23.78% at 6, 12, and 18 months post treatment, respectively. However, a better trend of reduction in cardiovascular risk was observed in patients with a high baseline cardiovascular risk. The glucose-lowering effects of vildagliptin were significantly observed 12 months of treatment onwards, but non-significant changes were found in lipid and blood pressure levels as well as body mass index.

CONCLUSION

Vildagliptin provided a promising glucose-lowering effect in Thai patients with type 2 diabetes mellitus. However, the mean 10-year cardiovascular risk did not significantly decrease. However, a negative correlation between cardiovascular risk reduction and baseline cardiovascular risk was observed in this study. Low sample size was a major limitation of this study.

Utilization Rates of SGLT2 Inhibitors and GLP-1 Receptor Agonists and Their Facility-Level Variation Among Patients With Atherosclerotic Cardiovascular Disease and Type 2 Diabetes: Insights From the Department of Veterans Affairs

OBJECTIVE

There is mounting evidence regarding the cardiovascular benefits of sodium-glucose cotransporter 2 inhibitors (SGLT2i) and glucagon-like peptide 1 receptor agonists (GLP-1 RA) among patients with atherosclerotic cardiovascular disease (ASCVD) and type 2 diabetes mellitus (T2DM). There is paucity of data assessing real-world practice patterns for these drug classes. We aimed to assess utilization rates of these drug classes and facility-level variation in their use.

RESEARCH DESIGN AND METHODS

We used the nationwide Veterans Affairs (VA) health care system data set from 1 January 2020 to 31 December 2020 and included patients with established ASCVD and T2DM. Among these patients, we assessed the use of SGLT2i and GLP-1 RA and the facility-level variation in their use. Facility-level variation was computed using median rate ratios (MRR), a measure of likelihood that two random facilities differ in use of SGLT2i and GLP-1 RA in patients with ASCVD and T2DM.

RESULTS

Among 537,980 patients with ASCVD and T2DM across 130 VA facilities, 11.2% of patients received an SGLT2i while 8.0% of patients received a GLP-1 RA. Patients receiving these cardioprotective glucose-lowering drug classes were on average younger and had a higher proportion of non-Hispanic Whites. Overall, median (10th-90th percentile) facility-level rates were 14.92% (9.31-22.50) for SGLT2i and 10.88% (4.44-17.07) for GLP-1 RA. There was significant facility-level variation among SGLT2i use-MRRunadjusted: 1.41 (95% CI 1.35-1.47) and MRRadjusted: 1.55 (95% CI 1.46 -1.63). Similar facility-level variation was observed for use of GLP-1 RA-MRRunadjusted: 1.34 (95% CI 1.29-1.38) and MRRadjusted: 1.78 (95% CI 1.65-1.90).

CONCLUSIONS

Overall utilization rates of SGLT2i and GLP-1 RA among eligible patients are low, with significantly higher residual facility-level variation in the use of these drug classes. Our results suggest opportunities to optimize their use to prevent future adverse cardiovascular events among these patients.

Obesity management as a primary treatment goal for type 2 diabetes: time to reframe the conversation

Obesity is now recognised as a disease that is associated with serious morbidity and increased mortality. One of its main metabolic complications is type 2 diabetes, as the two conditions share key pathophysiological mechanisms. Weight loss is known to reverse the underlying metabolic abnormalities of type 2 diabetes and, as such, improve glucose control; loss of 15% or more of bodyweight can have a disease-modifying effect in people with type 2 diabetes, an outcome that is not attainable by any other glucose-lowering intervention. Furthermore, weight loss in this population exerts benefits that extend beyond glycaemic control to improve risk factors for cardiometabolic disease and quality of life. We review the evidence supporting the role of weight loss in the management of type 2 diabetes and propose that many patients with type 2 diabetes would benefit from having a primary weight-centric approach to diabetes treatment. We discuss the logistical challenges to implementing a new weight-centric primary treatment goal in people with type 2 diabetes.

Mini Review: Effect of GLP-1 Receptor Agonists and SGLT-2 Inhibitors on the Growth Hormone/IGF Axis

Accumulating evidence supports the early use of glucagon-like peptide-1 receptor agonists (GLP-1RAs) and sodium glucose transporter-2 inhibitors (SGLT-2is) for the treatment of type 2 diabetes. Indeed, these compounds exert numerous pleiotropic actions that favorably affect metabolism and diabetes comorbidities, showing an additional effect beyond glucose control. Although a substantial amount of knowledge has been generated regarding the mechanism of action of both drug classes, much remains to be understood. Growth hormone (GH) is an important driver for multiple endocrine responses involving changes in glucose and lipid metabolism, and affects several tissues and organs (e.g., bone, heart). It acts directly on several target tissues, including skeletal muscle and bone, but several effects are mediated indirectly by circulating (liver-derived) or locally produced IGF-1. In consideration of the multiple metabolic and cardiovascular effects seen in subjects treated with GLP-1RAs and SGLT-2is (e.g., reduction of hyperglycemia, weight loss, free/fat mass and bone remodeling, anti-atherosclerosis, natriuresis), it is reasonable to speculate that GH and IGF-1 may play a about a relevant role in this context. This narrative mini-review aims to describe the involvement of the GH/IGF-1/IGF-1R axis in either mediating or responding to the effects of each of the two drug classes.

Therapeutic Potential of Sunitinib in Ameliorating Endothelial Dysfunction in Type 2 Diabetic Rats

INTRODUCTION

Sunitinib, a multi-targeted tyrosine kinase receptor inhibitor used to treat renal-cell carcinoma and gastrointestinal stromal tumor, was recently shown to have a beneficial effect on metabolism in type 2 diabetes (T2D). Endothelial dysfunction is a key factor behind macro- and microvascular complications in T2D. The effect of sunitinib on endothelial function in T2D remains, however, unclear. We therefore tested the hypothesis that sunitinib ameliorates endothelial dysfunction in T2D.

METHODS

Sunitinib (2 mg/kg/day, by gavage) was administered to T2D Goto-Kakizaki (GK) rats for 6 weeks, while water was given to GK and Wistar rats as controls. Hemodynamic, inflammatory, and metabolic parameters as well as endothelial function were measured.

RESULTS

Systolic, mean arterial blood pressures, plasma tumor necrosis factor α levels, kidney weight to body weight (BW) ratio, and glucose levels were higher, while BW was lower in GK rats than in Wistar rats. Six-week treatment with sunitinib in GK rats did not affect these parameters but suppressed the increase in glucose levels. Endothelium-dependent relaxations were reduced in both aortas and mesenteric arteries isolated from GK as compared to Wistar rats, which was markedly reversed in both types of arteries from GK rats treated with sunitinib.

CONCLUSIONS

This study demonstrates that sunitinib has a glucose-lowering effect and ameliorates endothelial dysfunction in both conduit and resistance arteries of GK rats.

Prevention of Diabetes Macrovascular Complications and Heart Failure

Cardiovascular (CV) mortality in diabetes has declined substantially over the last 3 decades in high-income countries from a multifactorial approach targeting glucose, cholesterol, and blood pressure, and lower smoking rates. Additional CV gains may be achieved from large-scale weight loss, which ongoing trials are testing, and from delaying diabetes in those at highest risk. Finally, recent outcome trials support a role for (1) sodium/glucose cotransporter-2 inhibitors, which lower major adverse cardiovascular events but incident heart failure more strongly, and (2) glucagon-like peptide-1 receptor agonists, which lower atherothrombotic outcomes more consistently, including stroke and peripheral arterial disease.

Hypertension in diabetes care: emerging roles of recent hypoglycemic agents

Patients with type 2 diabetes (T2D) frequently have multiple cardiovascular, metabolic, and renal comorbidities, such as hypertension, dyslipidemia, hyperuricemia, chronic kidney disease, and heart failure. Accordingly, this patient population often requires polypharmacy, which is associated with an increased risk of drug-drug interactions, poor adherence, and even adverse outcomes. Accumulating evidence on newer hypoglycemic agents, such as glucagon-like peptide-1 receptor agonists and sodium-glucose cotransporter 2 inhibitors, has highlighted the marked improvements in cardiovascular and renal outcomes associated with the off-target benefits for relevant comorbidities, including hypertension. These classes of hypoglycemic agents are unique, as they achieve consistently modest but significant reductions in systolic and diastolic blood pressure (BP), an effect that has not been targeted and observed with conventional hypoglycemic agents. In addition to this BP-lowering effect, these agents also have multifaceted beneficial impacts on other cardiometabolic and renal parameters, which appear to be helpful for providing an important comprehensive therapeutic approach to improve the prognosis in patients with T2D. The clinical advantages of these agents may reduce the dose and number of concomitant medications used to treat T2D and related comorbidities. These positive spillover effects may also enhance the clinical use of agents to achieve better diabetes care. As a consequence, the clinical significance of these hypoglycemic agents now extends beyond their hypoglycemic effects, thereby providing a new-normal strategy to use in an evidence-based, patient-centric approach to diabetes care.

Effects of Empagliflozin on Myocardial Flow Reserve in Patients With Type 2 Diabetes Mellitus: The SIMPLE Trial

Background

Sodium–glucose cotransporter 2 inhibitors reduce hospitalizations for heart failure and cardiovascular death, although the underlying mechanisms have not been resolved. The SIMPLE trial (The Effects of Empagliflozin on Myocardial Flow Reserve in Patients With Type 2 Diabetes Mellitus) investigated the effects of empagliflozin on myocardial flow reserve (MFR) reflecting microvascular perfusion, in patients with type 2 diabetes mellitus at high cardiovascular disease risk.

Methods and Results

We randomized 90 patients to either empagliflozin 25 mg once daily or placebo for 13 weeks, as add‐on to standard therapy. The primary outcome was change in MFR at week 13, quantified by Rubidium‐82 positron emission tomography/computed tomography. The secondary key outcomes were changes in resting rate‐pressure product adjusted MFR, changes to myocardial flow during rest and stress, and reversible cardiac ischemia. Mean baseline MFR was 2.21 (95% CI, 2.08–2.35). There was no change from baseline in MFR at week 13 in either the empagliflozin: 0.01 (95% CI, −0.18 to 0.21) or placebo groups: 0.06 (95% CI, −0.15 to 0.27), with no treatment effect −0.05 (95% CI, −0.33 to 0.23). No effects on the secondary outcome parameters by Rubidium‐82 positron emission tomography/computed tomography was observed. Treatment with empagliflozin reduced hemoglobin A_1c by 0.76% (95% CI, 1.0–0.5; P<0.001) and increased hematocrit by 1.69% (95% CI, 0.7–2.6; P<0.001).

Conclusions

Empagliflozin did not improve MFR among patients with type 2 diabetes mellitus and high cardiovascular disease risk. The present study does not support that short‐term improvement in MFR explains the reduction in cardiovascular events observed in the outcome trials.

Registration

URL: https://clinicaltrialsregister.eu/; Unique identifier: 2016‐003743‐10.

Role of Glucose-Lowering Medications in Erectile Dysfunction

Erectile dysfunction (ED) is a long-term complication of type 2 diabetes (T2D) widely known to affect the quality of life. Several aspects of altered metabolism in individuals with T2D may help to compromise the penile vasculature structure and functions, thus exacerbating the imbalance between smooth muscle contractility and relaxation. Among these, advanced glycation end-products and reactive oxygen species derived from a hyperglycaemic state are known to accelerate endothelial dysfunction by lowering nitric oxide bioavailability, the essential stimulus of relaxation. Although several studies have explained the pathogenetic mechanisms involved in the generation of erectile failure, few studies to date have described the efficacy of glucose-lowering medications in the restoration of normal sexual activity. Herein, we will present current knowledge about the main starters of the pathophysiology of diabetic ED and explore the role of different anti-diabetes therapies in the potential remission of ED, highlighting specific pathways whose activation or inhibition could be fundamental for sexual care in a diabetes setting.

Heart Failure and Diabetes Mellitus: Biomarkers in Risk Stratification and Prognostication

Heart failure (HF) and type 2 diabetes mellitus (T2DM) have a synergistic effect on cardiovascular (CV) morbidity and mortality in patients with established CV disease (CVD). The aim of this review is to summarize the knowledge regarding the discriminative abilities of conventional and novel biomarkers in T2DM patients with established HF or at higher risk of developing HF. While conventional biomarkers, such as natriuretic peptides and high-sensitivity troponins demonstrate high predictive ability in HF with reduced ejection fraction (HFrEF), this is not the case for HF with preserved ejection fraction (HFpEF). HFpEF is a heterogeneous disease with a high variability of CVD and conventional risk factors including T2DM, hypertension, renal disease, older age, and female sex; therefore, the extrapolation of predictive abilities of traditional biomarkers on this population is constrained. New biomarker-based approaches are disputed to be sufficient for improving risk stratification and the prediction of poor clinical outcomes in patients with HFpEF. Novel biomarkers of biomechanical stress, fibrosis, inflammation, oxidative stress, and collagen turn-over have shown potential benefits in determining prognosis in T2DM patients with HF regardless of natriuretic peptides, but their role in point-to-care and in routine practice requires elucidation in large clinical trials.

Clinical profiles and quality of care of subjects with type 2 diabetes according to their cardiovascular risk: an observational, retrospective study

Background

The European Society of Cardiology (ESC) recently defined cardiovascular risk classes for subjects with diabetes. Aim of this study was to explore the distribution of subjects with type 2 diabetes (T2D) by cardiovascular risk groups according to the ESC classification and to describe the quality indicators of care, with particular regard to cardiovascular risk factors.

Methods

The study is based on data extracted from electronic medical records of patients treated at the 258 Italian diabetes centers participating in the AMD Annals initiative. Patients with T2D were stratified by cardiovascular risk. General descriptive indicators, measures of intermediate outcomes, intensity/appropriateness of pharmacological treatment for diabetes and cardiovascular risk factors, presence of other complications and overall quality of care were evaluated.

Results

Overall, 473,740 subjects with type 2 diabetes (78.5% at very high cardiovascular risk, 20.9% at high risk and 0.6% at moderate risk) were evaluated. Among people with T2D at very high risk: 26.4% had retinopathy, 39.5% had albuminuria, 18.7% had a previous major cardiovascular event, 39.0% had organ damage, 89.1% had three or more risk factors. The use of DPP4-i markedly increased as cardiovascular risk increased. The prescription of secretagogues also increased and that of GLP1-RAs tended to increase. The use of SGLT2-i was still limited, and only slightly higher in subjects with very high cardiovascular risk. The overall quality of care, as summarized by the Q score, tended to be lower as the level of cardiovascular risk increased.

Conclusions

A large proportion of subjects with T2D is at high or very high risk. Glucose-lowering drug therapies seem not to be adequately used with respect to their potential advantages in terms of cardiovascular risk reduction. Several actions are necessary to improve the quality of care.

Effect of empagliflozin on ectopic fat stores and myocardial energetics in type 2 diabetes: the EMPACEF study

BACKGROUND

Empagliflozin is a sodium-glucose cotransporter 2 (SGLT2) inhibitor that has demonstrated cardiovascular and renal protection in patients with type 2 diabetes (T2D). We hypothesized that empaglifozin (EMPA) could modulate ectopic fat stores and myocardial energetics in high-fat-high-sucrose (HFHS) diet mice and in type 2 diabetics (T2D).

METHODS

C57BL/6 HFHS mice (n = 24) and T2D subjects (n = 56) were randomly assigned to 12 weeks of treatment with EMPA (30 mg/kg in mice, 10 mg/day in humans) or with placebo. A 4.7 T or 3 T MRI with 1H-MRS evaluation-myocardial fat (primary endpoint) and liver fat content (LFC)-were performed at baseline and at 12 weeks. In humans, standard cardiac MRI was coupled with myocardial energetics (PCr/ATP) measured with 31P-MRS. Subcutaneous (SAT) abdominal, visceral (VAT), epicardial and pancreatic fat were also evaluated. The primary efficacy endpoint was the change in epicardial fat volume between EMPA and placebo from baseline to 12 weeks. Secondary endpoints were the differences in PCr/ATP ratio, myocardial, liver and pancreatic fat content, SAT and VAT between groups at 12 weeks.

RESULTS

In mice fed HFHS, EMPA significantly improved glucose tolerance and increased blood ketone bodies (KB) and β-hydroxybutyrate levels (p < 0.05) compared to placebo. Mice fed HFHS had increased myocardial and liver fat content compared to standard diet mice. EMPA significantly attenuated liver fat content by 55%, (p < 0.001) but had no effect on myocardial fat. In the human study, all the 56 patients had normal LV function with mean LVEF = 63.4 ± 7.9%. Compared to placebo, T2D patients treated with EMPA significantly lost weight (- 2.6 kg [- 1.2; - 3.7]) and improved their HbA1c by 0.88 ± 0.74%. Hematocrit and EPO levels were significantly increased in the EMPA group compared to placebo (p < 0.0001, p = 0.041). EMPA significantly increased glycosuria and plasma KB levels compared to placebo (p < 0.0001, p = 0.012, respectively), and significantly reduced liver fat content (- 27 ± 23 vs. - 2 ± 24%, p = 0.0005) and visceral fat (- 7.8% [- 15.3; - 5.6] vs. - 0.1% [- 1.1;6.5], p = 0.043), but had no effect on myocardial or epicardial fat. At 12 weeks, no significant change was observed in the myocardial PCr/ATP (p = 0.57 between groups).

CONCLUSIONS

EMPA effectively reduced liver fat in mice and humans without changing epicardial, myocardial fat or myocardial energetics, rebutting the thrifty substrate hypothesis for cardiovascular protection of SGLT2 inhibitors. Trial registration NCT, NCT03118336. Registered 18 April 2017, https://clinicaltrials.gov/ct2/show/NCT03118336.

Cardiovascular effects and mechanisms of sodium-glucose cotransporter-2 inhibitors

Sodium-glucose cotransporter-2 inhibitors (SGLT2 inhibitors) are a new type of drug for the treatment of diabetes, and they have been proven to have a good hypoglycemic effect. Several lines of clinical evidence have shown that SGLT2 inhibitors can significantly reduce the risks of atherosclerosis, hospitalization for heart failure, cardiovascular death, and all-cause mortality and delay the progression of chronic kidney disease. Because of the protective effects of SGLT2 inhibitors on the heart and kidney, they are being studied for the treatment of heart failure and chronic kidney disease in patients without diabetes. Therefore, it is necessary for cardiologists, patients with diabetes, and nephrologists to fully understand this type of drug. In this review, we summarize the following three aspects of SGLT2 inhibitors: the recent clinical evidence of their cardiovascular benefits, their mechanisms of action, and their safety.

Efficacy of Dapagliflozin on Renal Function and Outcomes in Patients With Heart Failure With Reduced Ejection Fraction: Results of DAPA-HF

Supplemental Digital Content is available in the text.

Many patients with heart failure and reduced ejection fraction (HFrEF) have chronic kidney disease that complicates pharmacological management and is associated with worse outcomes. We assessed the safety and efficacy of dapagliflozin in patients with HFrEF, according to baseline kidney function, in the DAPA-HF trial (Dapagliflozin and Prevention of Adverse-outcomes in Heart Failure). We also examined the effect of dapagliflozin on kidney function after randomization.

Clinical Approach to Assessment and Amelioration of Atherosclerotic Vascular Disease in Diabetes

Atherosclerotic cardiovascular disease is increased on average 2–3-fold in people with diabetes as compared to their non-diabetic counterparts and is the major cause of the increased morbidity and mortality in this disease. There is however heterogeneity in cardiovascular risk between individuals based on demographic, cardiometabolic and clinical risk factors in the setting of hyperglycemia, insulin resistance and obesity that needs to be taken into consideration in planning preventive interventions. Randomized clinical trials of agents or procedures used for amelioration of augmented CVD risk in diabetes have been pivotal in providing evidenced-based treatments. Improvement in hyperglycemia in both type 1 and type 2 diabetes is considered to be central in the prevention of microvascular and macrovascular complications although selected antihyperglycemic agents have demonstrated beneficial as well as possible deleterious off-target effects. Lowering low density lipoprotein cholesterol, treating hypertension and stopping smoking each play important roles in preventing cardiovascular disease in diabetes as they do in the general population and low dose aspirin is overall beneficial in high risk individuals. Hypertriglyceridemia may represent another important marker for augmented cardiovascular risk in diabetes and newer agents targeting dyslipidemia appear promising. The fall in cardiovascular events over the past two decades offers hope that modern intervention strategies as well as novel approaches such as those targeting inflammation may contribute to a continued reduction of cardiovascular disease in people with diabetes.

GLP-1RAs and SGLT2is Reduce Cardiovascular Events Independent of Reductions of Systolic Blood Pressure and Body Weight: A Meta-Analysis with Meta-Regression

INTRODUCTION

The impact of reduction of systolic blood pressure or body weight on reduction of cardiovascular events during the treatment with glucagon-like peptide 1 receptor agonists (GLP-1RAs) or sodium-glucose cotransporter 2 inhibitors (SGLT2is) for type 2 diabetes is unclear.

METHODS

We searched Embase and PubMed. We performed meta-analysis using hazard ratio (HR) and 95% confidence interval (CI) as effect size stratified by drug class on six endpoints of interest, which were major adverse cardiovascular events (MACE), hospitalization for heart failure (HHF), cardiovascular death (CVD), myocardial infarction (MI), stroke, and all-cause death (ACD). We performed meta-regression to assess the difference between GLP-1RAs and SGLT2is, and the impact of reduction of systolic blood pressure or body weight on reduction of cardiovascular events.

RESULTS

We included 11 randomized trials. Compared with placebo, SGLT2is reduced HHF by 32% (HR 0.68, 95% CI 0.60-0.76) whereas GLP-1RAs reduced HHF by only 9% (HR 0.91, 95% CI 0.83-0.99). The benefit from SGLT2is on HHF was significantly greater than that from GLP-1RAs (P_subgroup = 0.004). GLP-1RAs reduced stroke by 16% (HR 0.84, 95% CI 0.76-0.93) whereas SGLT2is did not reduce stroke (HR 0.96, 95% CI 0.82-1.12). GLP-1RAs and SGLT2is similarly reduced MACE by 12%, CVD by 15%, MI by 9%, and ACD by 13%. The effects of systolic blood pressure reduction and body weight reduction on the logarithms of HRs of GLP-1RAs or SGLT2is vs. placebo as for reducing six endpoints of interest were not statistically significant (β ranged from - 0.145 to 0.269, and P ranged from 0.211 to 0.941).

CONCLUSIONS

GLP-1RAs and SGLT2is lead to similar benefits on MACE, CVD, MI, and ACD in adults with type 2 diabetes. The benefit from SGLT2is on HHF is greater than that from GLP-1RAs, while GLP-1RAs vs. placebo significantly reduce stroke whereas SGLT2is do not. The two drug classes reduce cardiovascular events independent of reductions of systolic blood pressure and body weight.

Beyond the myocardium? SGLT2 inhibitors target peripheral components of reduced oxygen flux in the diabetic patient with heart failure with preserved ejection fraction

Recent cardiovascular outcome trials have highlighted the propensity of the antidiabetic agents, SGLT2 inhibitors (SGLT2is or -flozin drugs), to exert positive clinical outcomes in patients with cardiovascular disease at risk for major adverse cardiovascular events (MACEs). Of interest in cardiac diabetology is the physiological status of the patient with T2DM and heart failure with preserved ejection fraction (HFpEF), a well-examined association. Underlying this pathologic tandem are the effects that long-standing hyperglycemia has on the ability of the HFpEF heart to adequately deliver oxygen. It is believed that shortcomings in oxygen diffusion or utilization and the resulting hypoxia thereafter may play a role in underlying the clinical sequelae of patients with T2DM and HFpEF, with implications in the long-term decline of extra-cardiac tissue. Oxygen consumption is one of the most critical factors in indexing heart failure disease burden, warranting a probe into the role of SGLT2i on oxygen utility in HFpEF and T2DM. We investigated the role of oxygen flux in the patient with T2DM and HFpEF extending beyond the heart with focuses on cellular metabolism, perivascular fibrosis with endothelial dysfunction, hematologic changes, and renal effects with neurohormonal considerations in the patient with HFpEF and T2DM. Moreover, we give a commentary on potential therapeutic targets of these components with SGLT2i to gain insight into disease burden amelioration in patients with HFpEF and T2DM.