The risks and benefits of aldosterone antagonists

The Effectiveness of Eplerenone vs Spironolactone on Left Ventricular Systolic Function, Hospitalization and Cardiovascular Death in Patients With Chronic Heart Failure-HFrEF

Background

Heart failure remains one of the most prevalent clinical syndromes associated with significant morbidity and mortality. According to current guidelines, the prescription of a MRA is recommended to reduce the risk of HF hospitalization and death in all patients with symptomatic heart failure and no contraindications for this therapy.

Objective

The aim of our study was to determine the efficacy of eplerenone vs. spironolactone on left ventricular systolic function by measuring left ventricle ejection fraction (LVEF) in patients with chronic heart failure, especially their effect on preventing hospitalization, reducing mortality, and improving clinical status among patients with chronic HF.

Methods

From June 2021 to June 2022, the study was a randomized, prospective clinical trial single blind study. A total of 142 patients of chronic heart failure with reduced ejection fraction were selected by random sampling. Each patient was randomly allocated into either of the two groups and was continued receiving treatment with either spironolactone (Spiron-HF group) or eplerenone (Epler-HF group). Patients in Epler-HF group were compared with an arm of the same size and matched by age and gender patients in Spiron-HF group for management of chronic HFrEF. Each patient was evaluated clinically, biochemically, and echocardiographically at the beginning of treatment (baseline) after 6 months and at the end of 12th month. Echocardiography was performed to find out change in left ventricular systolic function.

Results

After 12 months of treatment, significant improvement of left ventricular ejection fraction was observed in eplerenone treated arm (37.9 ± 3.8 ± 4.6 in Spiron-HF group versus 40.1 ± 5.7 in Epler-HF group; P < 0.05). A significant reduction in left ventricular end-systolic volume (6.3 ± 2.5ml in Spiron-HF versus 17.8± 4.4ml in Epler-HF group; P < 0.05) and left ventricular systolic diameter volume (2.7 ± 0.5ml in Spiron-HF versus 6.7 ± 0.2ml in Epler-HF group; P < 0.05), occurred after 12 months of treatment. Left ventricular global longitudinal strain (LV GLS) was significantly improved in Epler-HF group compared with Spiron-HF group (0.6 ± 0.4 versus 3.4 ± 0.9; P < 0.05). There were no significant differences observed in reduction of left ventricular end-diastolic volume (2.2 ± 0.5 ml versus 4.7 ± 1.1ml; P =0.103) and left ventricular diastolic diameter (1.2 ± 0.6 versus 1.7 ± 0.3; P=0.082) in both arms. The effects of both MRA agents spironolactone and eplerenone on the primary composite outcome, each of the individual mortality and hospital admission outcomes are shown in Figure 1 and 2. Patients of the Epler-HF group showed statistically significant lower cardiovascular mortality (HR 0.53; 95% CI 0.34-0.82; p= 0.007) and all-cause mortality (HR 0.64; 95% CI 0.44-0.93; p= 0.022) than patients of the Spiron-HF group. The statistical analysis did not show a statistically significant difference between Epler -HF and Spiron-HF study groups regarding the risk of the primary composite outcome; cardiovascular death or hospitalization due to HF (Hazard Ratio (HR) eplerenone vs. spironolactone = 0.95; 95% Confidence Interval (CI) 0.73- 1.27; p= 0.675).

Conclusion

Our study has demonstrated favorable effects of eplerenone on cardiac remodeling parameters and reduction of cardiovascular mortality and all-cause mortality compared with spironolactone in the treatment of HFrEF. The ability of eplerenone to effectively block the mineralocorticoid receptor while minimizing side effects and a significant reduction in the risk of hospitalization and cardiovascular death confirms its key role in the treatment of patients with chronic HFrEF.

Differential effects of eplerenone versus amlodipine on muscle metaboreflex function in hypertensive humans

Numerous studies have demonstrated that sympathetic nervous system overactivation during exercise in hypertensive rodents and humans is due, in part, to an exaggerated reflex response known as the exercise pressor reflex. Our prior studies have implicated a key role of mineralocorticoid receptor activation in mediating an augmented exercise pressor reflex in spontaneously hypertensive rats, which is mitigated by blockade with eplerenone. However, the effect of eplerenone on exercise pressor reflex has not been assessed in human hypertension. Accordingly, the authors performed a randomized crossover study to compare the effects of eplerenone to another antihypertensive drug from a different class amlodipine on sympathetic nerve activity (SNA) in 14 patients with uncomplicated hypertension. The authors found that amlodipine unexpectedly augmented the increase in SNA during the second minute of isometric handgrip, which persisted into the post‐exercise circulatory arrest period (∆ SNA, from rest of 15 ± 2 vs. 9 ± 2 vs. 10 ± 2 bursts/min, amlodipine vs. baseline vs. eplerenone, respectively, p < .01), suggesting an exaggerated muscle metaboreflex function. Eplerenone did not alter sympathetic responses to exercise or post‐exercise circulatory arrest in the same hypertensive individuals. In conclusions, our studies provide the first direct evidence for a potentially unfavorable potentiation of muscle metaboreflex by amlodipine during isometric handgrip exercise in hypertensive patients whereas eplerenone has no significant effect. Our study may have clinical implications in terms of selection of antihypertensive agents that have the least detrimental effects on sympathetic neural responses to isometric exercise.

Sodium and Volume Disorders in Advanced Chronic Kidney Disease

The kidney has a remarkable ability to modulate sodium and water excretion to maintain homeostasis despite a widely varying dietary intake. However, as glomerular filtration rate falls to less than 30 mL/min, this ability can be compromised leading to an increased risk for disorders of serum sodium and extracellular volume. In all cases, these disorders are associated with an increased rate of morbidity and mortality. Management strategies to both prevent and treat these conditions are available but requiring special attention to the unique circumstance of advanced CKD to maximize therapeutic response and prevent complications.

Eplerenone: a review of its use in patients with chronic systolic heart failure and mild symptoms

Eplerenone (Inspra®) is a selective mineralocorticoid receptor antagonist (MRA). In the EU, it is approved for use (in addition to standard optimal therapy) to reduce the risk of cardiovascular (CV) mortality and morbidity in adult patients with chronic systolic heart failure (HF) and mild symptoms. This article reviews the efficacy and tolerability of eplerenone in this indication and briefly summarizes its pharmacology. In the EMPHASIS-HF study, relative to placebo, the addition of eplerenone to optimal background therapy significantly reduced the risk of death from CV causes or hospitalization for HF in patients with chronic systolic HF and mild symptoms. Benefits of eplerenone therapy over placebo were also observed in several secondary outcomes, including: death from any cause or hospitalization for HF; death from any cause; hospitalization for any reason; or hospitalization for HF. Eplerenone was generally well tolerated in this study, with the most frequent adverse event being hyperkalaemia, which is a known adverse event of the drug class. Sexual adverse events (e.g. gynecomastia) occurred in <1 % of eplerenone recipients, reflecting the selectivity of eplerenone for mineralocorticoid receptors. Based on these results, European guidelines have been updated and recommend the use of an MRA to reduce the risk of HF hospitalization and premature death in all patients with persisting symptoms (New York Heart Association class II-IV) and a left-ventricular ejection fraction of ≤35 %, despite treatment with ACE inhibitor (or an angiotensin receptor blocker if an ACE inhibitor is not tolerated) and a β-blocker.

Association of spironolactone use with all-cause mortality in heart failure: a propensity scored cohort study

BACKGROUND

In 3 randomized controlled trials in heart failure (HF), mineralocorticoid receptor antagonists reduced mortality. The net benefit from randomized controlled trials may not be generalizable, and eplerenone was, but spironolactone was not, studied in mild HF. We tested the hypothesis that spironolactone is associated with reduced mortality also in a broad unselected contemporary population with HF and reduced ejection fraction, in particular New York Heart Association (NYHA) I-II.

METHODS AND RESULTS

We prospectively studied 18 852 patients (age 71±12 years; 28% women) with NYHA I-IV and ejection fraction <40% who were registered in the Swedish Heart Failure Registry between 2000 and 2012 and who were (n=6551) or were not (n=12 301) treated with spironolactone. We derived propensity scores for spironolactone treatment based on 41 covariates. We assessed survival by Cox regression with adjustment for propensity scores and with matching based on propensity score. We performed sensitivity and residual confounding analyses and analyzed the NYHA I-II and III-IV subgroups separately. One-year survival was 83% versus 84% in treated versus untreated patients (log rank P<0.001). After adjustment for propensity scores, the hazard ratio for spironolactone was 1.05 (95% confidence interval, 1.00-1.11; P=0.054). Spironolactone interacted with NYHA (P<0.001). In the NYHA I-II subgroup, after adjustment for propensity scores, the hazard ratio for spironolactone was 1.11 (95% confidence interval, 1.02-1.21; P=0.019).

CONCLUSIONS

In an unselected contemporary population of HF with reduced ejection fraction, spironolactone was not associated with reduced mortality. The net benefits of spironolactone may be lower outside the clinical trial setting and in milder HF.

Pharmacologic Issues in treating hypertension in CKD

Antihypertensive drugs are prescribed to patients with CKD to slow down the rate of loss of residual kidney function; to reduce proteinuria, when present; and to protect other target organs from damage that is mediated by elevated blood pressure (BP). In most patients, a diuretic and a renin system blocking drug, such as an angiotensin-converting enzyme inhibitor, angiotensin receptor antagonist, or an aldosterone receptor antagonist are used. Often, 3 or more drugs are needed to achieve BP goals. Many drugs are eliminated through the kidney and in some cases dosage reductions are advisable to avoid adverse effects from high levels of medication. This article will review the various classes of antihypertensive drugs used in the management of high BP in patients with CKD, with an emphasis on pitfalls that arise when kidney function is impaired.

Endocrine causes of secondary hypertension

Secondary hypertension is common in clinical practice if a broad definition is applied. Various patterns of hypertension exist in the patient with an endocrine source of their disease, including new-onset hypertension in a previously normotensive individual, a loss of blood pressure control in a patient with previously well-controlled blood pressure, and/or labile blood pressure in the setting of either of these 2 patterns. A thorough history and physical exam, which can rule out concomitant medications, alcohol intake, and over-the-counter medication use, is an important prerequisite to the workup for endocrine causes of hypertension. Endocrine forms of secondary hypertension, such as pheochromocytoma and Cushing's disease, are extremely uncommon. Conversely, primary aldosteronism now occurs with sufficient frequency so as to be considered "top of the list" for secondary endocrine causes in otherwise difficult-to-treat or resistant hypertension. Primary aldosteronism can be insidious in its presentation since a supposed hallmark finding, hypokalemia, may be variable in its presentation. It is important to identify secondary causes of hypertension that are endocrine in nature because surgical intervention may result in correction or substantial improvement of the hypertension.

A comparison of the aldosterone-blocking agents eplerenone and spironolactone

Improved understanding of the adverse pharmacological properties of aldosterone has prompted investigation of the clinical benefits of blocking aldosterone at the receptor level. This article reviews the pharmacology, clinical efficacy, and tolerability of the two available blocking agents, spironolactone and eplerenone. A Medline search identified clinical studies assessing spironolactone and eplerenone. Priority was given to large, well-controlled, clinical trials and comparative studies. Pharmacological differences between spironolactone and eplerenone include lower affinity of eplerenone for progesterone, androgen, and glucocorticoid receptors; more consistently demonstrated nongenomic properties for eplerenone; and the presence of long-acting metabolites for spironolactone. Both agents effectively treat hypertension and heart failure but comparisons are complicated by the deficiency of head-to-head trials and differences between patient populations. There are differences in the tolerability profiles; spironolactone is associated with dose-dependent sexual side effects. Both agents produce dose-dependent increases in potassium concentrations, although the effect with spironolactone appears to be greater when both agents are administered at recommended doses. Choice of a specific agent should be based on individual patient issues, such as the nature of heart failure and patient concerns about adverse events.

Antiangiogenic effects of spironolactone and other potassium-sparing diuretics in human umbilical vein endothelial cells and in fibrin gel chambers implanted in rats

OBJECTIVE

Potassium-sparing diuretics have different effects on angiogenesis that may mediate some abilities to treat cardiovascular diseases. The aim of the current study was to compare the effects of spironolactone and an active metabolite, canrenone, or a derivative, eplerenone, and amiloride, a diuretic without affecting mineralocorticoid activity, on the proliferation of human umbilical vein endothelial cells (HUVEC) and on angiogenesis in fibrin gel chambers implanted in rats.

MATERIALS AND METHODS

We measured the effects of spironolactone, canrenone, eplerenone, and amiloride on the proliferation of HUVEC in the presence or absence of vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF). We also examined the effects of these compounds on migration and capillary tube formation by HUVEC. Finally, the effects of the compounds on neovessel formation in vivo were investigated by implanting Wistar rats for 14 days with perforated Plexiglas chambers containing rat fibrin.

RESULTS

Spironolactone and amiloride inhibited the proliferation of HUVEC, but canrenone and eplerenone had no effect. The inhibitory effect of spironolactone was not prevented by VEGF or bFGF. Aldosterone had no effect on spironolactone-induced inhibition of HUVEC proliferation. Spironolactone induced a dose-dependent reduction of both cell chemotaxis and capillary tube formation. In fibrin gel chambers, spironolactone and amiloride significantly reduced the numbers of both peripheral and central neovessels. Canrenone and eplerenone, in contrast, had no antiangiogenic effect.

CONCLUSION

Spironolactone and amiloride significantly inhibited angiogenesis in vitro and in the fibrin gel chamber in vivo. Spironolactone antiangiogenic effects are unrelated to antimineralocorticoid activity.