Effect of empagliflozin on left ventricular contractility and peak oxygen uptake in subjects with type 2 diabetes without heart disease: results of the EMPA-HEART trial

Background

The mechanism through which sodium-glucose cotransporter 2 inhibitors (SGLT2i) prevent the incidence of heart failure and/or affect cardiac structure and function remains unclear.

Methods

The EMPA-HEART trial is aimed at verifying whether empagliflozin improves myocardial contractility (left ventricle global longitudinal strain, LV-GLS) and/or cardiopulmonary fitness (peak oxygen uptake, VO2peak) in subjects with type 2 diabetes (T2D) without heart disease. Patients with T2D, normal LV systolic function (2D-Echo EF > 50%), and no heart disease were randomized to either empagliflozin 10 mg or sitagliptin 100 mg for 6 months and underwent repeated cardiopulmonary exercise tests with echocardiography and determination of plasma biomarkers.

Results

Forty-four patients completed the study, 22 per arm. Despite comparable glycaemic control, modest reductions in body weight (− 1.6; [− 2.7/− 0.5] kg, p = 0.03) and plasma uric acid (− 1.5; [− 2.3/− 0.6], p = 0.002), as well as an increase in haemoglobin (+ 0.7; [+ 0.2/+ 1.1] g/dL, p = 0.0003) were evident with empagliflozin. No difference was detectable in either LV-GLS at 1 month (empagliflozin vs sitagliptin: + 0.44; [− 0.10/+ 0.98]%, p = 0.11) and 6 months of therapy (+ 0.53; [− 0.56/+ 1.62]%), or in VO_2peak (+ 0.43; [− 1.4/+ 2.3] mL/min/kg, p = 0.65). With empagliflozin, the subgroup with baseline LV-GLS below the median experienced a greater increase (time*drug p < 0.05) in LV-GLS at 1 month (+ 1.22; [+ 0.31/+ 2.13]%) and 6 months (+ 2.05; [+ 1.14/+ 2.96]%), while sitagliptin induced a modest improvement in LV-GLS only at 6 months (+ 0.92; [+ 0.21/+ 0.62]%).

Conclusions

Empagliflozin has neutral impact on both LV-GLS and exercise tolerance in subjects with T2D and normal left ventricular function. However, in patients with subclinical dysfunction (LV-GLS < 16.5%) it produces a rapid and sustained amelioration of LV contractility.

Trial registration EUDRACT Code 2016-002225-10

Supplementary Information

The online version contains supplementary material available at 10.1186/s12933-022-01618-1.

Plaque characteristics and biomarkers predicting regression and progression of carotid atherosclerosis

The factors that influence the atherosclerotic disease process in high-risk individuals remain poorly understood. Here, we used a combination of vascular imaging, risk factor assessment, and biomarkers to identify factors associated with 3-year change in carotid disease severity in a cohort of high-risk subjects treated with preventive therapy (n = 865). The results show that changes in intima-media thickness (IMT) are most pronounced in the carotid bulb. Progression of bulb IMT demonstrates independent associations with baseline bulb IMT, the plaque gray scale median (GSM), and the plasma level of platelet-derived growth factor (PDGF) (standardized β-coefficients and 95% confidence interval [CI] −0.14 [−0.06 to −0.02] p = 0.001, 0.15 [0.02–0.07] p = 0.001, and 0.20 [0.03–0.07] p < 0.001, respectively). Plasma PDGF correlates with the plaque GSM (0.23 [0.15–0.29] p < 0.001). These observations provide insight into the atherosclerotic process in high-risk subjects by showing that progression primarily occurs in fibrotic plaques and is associated with increased levels of PDGF.

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High age, male gender, and smoking increases risk of carotid disease progression

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Plaques that progress are more echogenic, indicating an increased degree of fibrosis

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Progression is associated with high plasma levels of pro-fibrotic growth factors

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Regression is most common in large, less fibrotic plaques

Use of Vascular Assessments and Novel Biomarkers to Predict Cardiovascular Events in Type 2 Diabetes: The SUMMIT VIP Study

OBJECTIVE

Cardiovascular disease (CVD) risk prediction represents an increasing clinical challenge in the treatment of diabetes. We used a panel of vascular imaging, functional assessments, and biomarkers reflecting different disease mechanisms to identify clinically useful markers of risk for cardiovascular (CV) events in subjects with type 2 diabetes (T2D) with or without manifest CVD.

RESEARCH DESIGN AND METHODS

The study cohort consisted of 936 subjects with T2D recruited at four European centers. Carotid intima-media thickness and plaque area, ankle-brachial pressure index, arterial stiffness, endothelial function, and circulating biomarkers were analyzed at baseline, and CV events were monitored during a 3-year follow-up period.

RESULTS

The CV event rate in subjects with T2D was higher in those with (n = 440) than in those without (n = 496) manifest CVD at baseline (5.53 vs. 2.15/100 life-years, P < 0.0001). New CV events in subjects with T2D with manifest CVD were associated with higher baseline levels of inflammatory biomarkers (interleukin 6, chemokine ligand 3, pentraxin 3, and hs-CRP) and endothelial mitogens (hepatocyte growth factor and vascular endothelial growth factor A), whereas CV events in subjects with T2D without manifest CVD were associated with more severe baseline atherosclerosis (median carotid plaque area 30.4 mm² [16.1-92.2] vs. 19.5 mm² [9.5-40.5], P = 0.01). Conventional risk factors, as well as measurements of arterial stiffness and endothelial reactivity, were not associated with CV events.

CONCLUSIONS

Our observations demonstrate that markers of inflammation and endothelial stress reflect CV risk in subjects with T2D with manifest CVD, whereas the risk for CV events in subjects with T2D without manifest CVD is primarily related to the severity of atherosclerosis.

Clinical Phenotype and Microvascular Dynamics of Subjects with Endothelial Dysfunction as Assessed by Peripheral Tonometry

OBJECTIVE

To evaluate the characteristics and the determinants of ED, as measured by PAT.

METHODS

We measured basal and post-ischemic digital pulse amplitude (EndoPAT(®)) in a mixed outpatient population of 206 diabetic and 101 non-diabetic subjects, of whom 50% with clinically manifest CVD, undergoing to an extensive clinical, biochemical, and vascular phenotype characterization.

RESULTS

The major characteristics of ED (tertile 1 vs 3), in addition to lower post-ischemic vasodilatory reserve (34 vs 203%), were a 3-fold higher baseline pulse amplitude and a delayed (60 second) peak response. The main determinant of this response was the baseline pulse amplitude (Stβ = -0.59), which in turn was influenced by age (Stβ = 0.13), central obesity (Stβ = 0.27) and inversely by HDL cholesterol (Stβ = -0.17), and systolic blood pressure (Stβ = -0.19). No association was observed with cardiovascular risk factors, previous cardiovascular event or extent of atherosclerosis (ABI and IMT, PWV). Most of the variability in baseline pulse amplitude remained unexplained (r(2) = 0.14).

CONCLUSIONS

ED, as detected by PAT in a population enriched with subjects at risk for CVD neither reflects the burden of classical risk factors (under treatment) nor the severity of atherosclerosis. Aside from central obesity and HDL cholesterol, most of the factors responsible for this ED remain unknown.

Association between renin and atherosclerotic burden in subjects with and without type 2 diabetes

Background

Activation of the renin-angiotensin-aldosterone-system (RAAS) has been proposed to contribute to development of vascular complications in type 2 diabetes (T2D). The aim of the present study was to determine if plasma renin levels are associated with the severity of vascular changes in subjects with and without T2D.

Methods

Renin was analyzed by the Proximity Extension Assay in subjects with (n = 985) and without (n = 515) T2D participating in the SUMMIT (SUrrogate markers for Micro- and Macro-vascular hard endpoints for Innovative diabetes Tools) study and in 205 carotid endarterectomy patients. Vascular changes were assessed by determining ankle-brachial pressure index (ABPI), carotid intima-media thickness (IMT), carotid plaque area, pulse wave velocity (PWV) and the reactivity hyperemia index (RHI).

Results

Plasma renin was elevated in subjects with T2D and demonstrated risk factor-independent association with prevalent cardiovascular disease both in subjects with and without T2D. Renin levels increased with age, body mass index, HbA1c and correlated inversely with HDL. Subjects with T2D had more severe carotid disease, increased arterial stiffness, and impaired endothelial function. Risk factor-independent associations between renin and APBI, bulb IMT, carotid plaque area were observed in both T2D and non-T2D subjects. These associations were independent of treatment with RAAS inhibitors. Only weak associations existed between plasma renin and the expression of pro-inflammatory and fibrous components in plaques from 205 endarterectomy patients.

Conclusions

Our findings provide clinical evidence for associations between systemic RAAS activation and atherosclerotic burden and suggest that this association is of particular importance in T2D.

HDL lipid composition is profoundly altered in patients with type 2 diabetes and atherosclerotic vascular disease

BACKGROUND AND AIMS

We have previously shown that the anti-inflammatory and anti-oxidant functions of HDL are impaired in T2D patients. In this study, we examined whether HDL from T2D patients contains elevated levels of oxidized fatty acids and whether those levels correlate with cardiovascular disease (CVD).

METHODS AND RESULTS

HETEs and HODEs on HDL were determined by LC-MS/MS in 40 non-diabetic controls (ND), 40 T2D without CVD (D⁺CVD⁻) and 38 T2D with known history of CVD (D⁺CVD⁺). HDL oxidant index was evaluated by a cell-free assay using dichlorofluorescein. Twenty-six randomly selected subjects from the three groups underwent coronary calcium score evaluation (CAC). Major cardiovascular risk factors were similar among the groups. HETEs and HODEs content were significantly increased in HDL from D⁺CVD⁺ when compared to D⁺CVD⁻ and ND patients. HDL oxidant index was not different among the three groups; however, it was significantly higher in patients with CAC score >100 when compared to patients with CAC score <100.

CONCLUSION

Patients with D⁺CVD⁻ and D⁺CVD⁺ are characterized by a severe, graded enrichment of oxidized fatty acids on HDL. In the present study, a loss of HDL function (as estimated by the HDL oxidant index) is observed only in patients with more advanced atherosclerosis.

Short-term acute hyperinsulinemia and prothrombotic factors in subjects with normal glucose tolerance

Some cytokines and proinflammatory mediators are considered markers of increased atherothrombotic risk. Few information is available on the effects of acute glucose and insulin variations on these markers of atherosclerosis. We assessed the acute effect of glucose and insulin on soluble CD40 ligand (sCD40L), IL-6, and P-selectin levels, evaluating their relationship with insulin sensitivity in normal glucose tolerance subjects (NGT). Twenty-four NGT subjects underwent a 3-h oral glucose tolerance test (OGTT) with measurements of sCD40L, IL-6, and P-selectin levels at 0, 90 and 180 min. Insulin sensitivity was assessed by the Oral Glucose Sensitivity Index (OGIS). To distinguish the role of glucose and insulin, eight subjects had the plasma glucose profile of the OGTT reproduced by a variable IV glucose infusion (ISO-G study) and nine underwent a euglycemic clamp. Lastly, a 3-h time-control (TC) study was performed in eleven subjects. A significant reduction of sCD40L was observed during OGTT and ISO-G study. This reduction was not due to time-related changes, since it was not observed in TC study. During the clamp, insulin induced a marked drop in sCD40L (from 4.89+/-1.34 to 1.60+/-0.29 ng/ml, p<0.05). In the pooled data from all studies, fasting sCD40L was indirectly related to LDL-cholesterol (r=-0.38; p=0.04), while IL-6 was directly related with BMI, fat mass, waist circumference, and P-selectin (p<0.05). sCD40L levels are downregulated during a short-term period of acute hyperinsulinemia, whether induced by oral or intravenous glucose administration or by insulin infusion, while it does not seem to affect P-selectin and IL-6.