Race Influences the Safety and Efficacy of Spironolactone in Severe Heart Failure

Renal effects and safety between Asian and non-Asian chronic kidney disease and type 2 diabetes treated with nonsteroidal mineralocorticoid antagonists

BACKGROUND

Asians bear a heavier burden of chronic kidney disease (CKD), a common comorbidity of type 2 diabetes mellitus (T2DM), than non-Asians. Nonsteroidal mineralocorticoid receptor antagonists (MRAs) have garnered attention for their potential advantages in renal outcomes. Nevertheless, the impact on diverse ethnic groups remains unknown.

METHODS

The PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure (CNKI), Wanfang database, and clinical trial registries were searched through August 2023 with the following keywords: nonsteroidal MRAs (finerenone, apararenone, esaxerenone, AZD9977, KBP-5074), CKD, T2DM, and randomized controlled trial (RCT). A random effects model was used to calculate overall effect sizes.

RESULTS

Seven RCTs with 14 997 participants were enrolled. Nonsteroidal MRAs reduced urinary albumin to creatinine ratio (UACR) significantly more in Asians than non-Asians: (weighted mean difference [WMD], -0.59, 95% CI, -0.73 to -0.45, p < .01) vs (WMD, -0.29, 95% CI, -0.32 to -0.27, p < .01), respectively. The average decline of estimated glomerular filtration rate (eGFR) was similar in Asians and non-Asians (p > .05). Regarding systolic blood pressure (SBP), nonsteroidal MRAs had a better antihypertension performance in Asians (WMD, -5.12, 95% CI, -5.84 to -4.41, p < .01) compared to non-Asians (WMD, -3.64, 95% CI, -4.38 to -2.89, p < .01). A higher incidence of hyperkalemia and eGFR decrease ≥30% was found in Asians than non-Asians (p < .01).

CONCLUSIONS

Nonsteroidal MRAs exhibited significant renal benefits by decreasing UACR and lowering SBP in Asian than that of non-Asian patients with CKD and T2DM, without increase of adverse events except hyperkalemia and eGFR decrease ≥30%.

Safety and Efficacy of Spironolactone in Dialysis-Dependent Patients: Meta-Analysis of Randomized Controlled Trials

Background

Patients with end-stage renal disease (ESRD) are characterized with high risk of heart failure. Although mineralocorticoid receptor antagonists have beneficial effect on relieving cardiac fibrosis and, thus, reduce the incidence of cardiovascular disease and cardiac death, the therapeutic benefits and adverse effects are still controversial. We conducted a meta-analysis to measure the safety and efficacy of spironolactone in patients undergoing dialysis.

Methods

A systematic search for randomized controlled trials (RCTs) was performed in PubMed, Embase, and Cochrane databases. Primary outcomes included changes in all-cause mortality (ACM), serum potassium concentration, incidence of hyperkalemia and gynecomastia (GYN). Secondary outcomes included changes in blood pressure (BP), left ventricular mass index (LVMI) and left ventricular ejection fraction (LVEF). Subgroup analysis and sensitivity analysis were further conducted. This research was registered with PROSPERO (International Prospective Register of Systematic Reviews; No. CRD42021287493).

Results

Fifteen RCTs with 1,258 patients were enrolled in this pooled-analysis. Spironolactone treatment significantly decreased ACM (RR = 0.42, P < 0.0001), CCV (RR = 0.54, P = 0.008) and LVMI (MD = −6.28, P = 0.002), also increased occurrence of GYN (RR = 4.36, P = 0.0005). However, LVEF (MD = 2.63, P = 0.05), systolic BP (MD = −4.61, P = 0.14) and diastolic BP (MD = −0.12, P = 0.94) did not change between two groups after treatment. Although serum potassium concentration was increased (MD = 0.22, P < 0.0001) after spironolactone supplement, the risk of hyperkalemia remained unchanged (RR = 1.21, P = 0.31). Further subgroup analysis found more obvious advantageous as well as disadvantageous effects in Asian subjects than European or American ones. Also, with more than 9 months of treatment duration, patients achieved more favorable influence than shorter duration.

Conclusions

These results highlight the therapeutic effects of spironolactone on cardiovascular indexes, including ACM, CCV, and LVMI. However, the unignorable increase of GYN incidence and serum potassium level indicate that close monitor in dialysis-dependent patients, especially Asian patients, is essential.

NR3C2 genotype is associated with response to spironolactone in diastolic heart failure patients from the Aldo-DHF trial

STUDY OBJECTIVE

This study aimed to determine if variants in NR3C2, which codes the target protein of spironolactone, or CYP11B2, which is involved in aldosterone synthesis, were associated with spironolactone response, focused on the primary end point of diastolic function (E/e'), in Aldosterone Receptor Blockade in Diastolic Heart Failure (Aldo-DHF) participants.

DESIGN

Post-hoc genetic analysis.

DATA SOURCE

Data and samples were derived from the multi-center, randomized, double-blind, placebo-controlled Aldo-DHF trial.

PATIENTS

Aldo-DHF participants treated with spironolactone (n = 184) or placebo (n = 178) were included.

INTERVENTION

Participants were genotyped for NR3C2 rs5522, NR3C2 rs2070951 and CYP11B2 rs1799998 via pyrosequencing.

MEASUREMENTS

In the placebo and spironolactone arms, separate multivariable linear regression analyses were performed for change in E/e' with each single nucleotide polymorphism (SNP), adjusted for age, sex, and baseline E/e'. To discern potential mechanisms of a genotype effect, associated SNPs were further examined for their association with change in blood pressure, circulating procollagen type III N-terminal peptide (PIIINP), and left atrial area.

MAIN RESULTS

Carriers of the rs5522 G allele in the placebo arm had a greater increase in E/e' over the 12-month course of the trial compared to noncarriers (β = 1.10; 95% confidence interval [CI]: 0.05-2.16; p = 0.04). No corresponding E/e' worsening by rs5522 genotype was observed in the spironolactone arm. None of the other genotypes were associated with change in E/e'. Compared to noncarriers, rs5522 G carriers also had a greater increase in left atrial area with placebo (β = 0.83; 95% CI: 0.17-1.48; p = 0.01) and a greater reduction in diastolic blood pressure with spironolactone (β = -3.56; 95% CI: -6.73 to -0.39; p = 0.03). Serum PIIINP levels were similar across rs5522 genotypes.

CONCLUSIONS

Our results suggest that spironolactone attenuates progression of diastolic dysfunction associated with the NR3C2 rs5522 G allele. Validation of our findings is needed.

Spironolactone Reduces Aortic Stiffness in Patients With Resistant Hypertension Independent of Blood Pressure Change

Background

Aortic stiffness is an independent predictor of cardiovascular events in patients with arterial hypertension. Resistant hypertension is often linked to hyperaldosteronism and associated with adverse outcomes. Spironolactone, a mineralocorticoid receptor antagonist, has been shown to reduce both the arterial blood pressure (BP) and aortic stiffness in resistant hypertension. However, the mechanism of aortic stiffness reduction by spironolactone is not well understood. We hypothesized that spironolactone reduces aortic stiffness in resistant hypertension independently of BP change.

Methods and Results

Patients with uncontrolled BP (≥140/90 mm Hg) despite use of ≥3 antihypertensive medications (including diuretics) were prospectively recruited. Participants were started on spironolactone at 25 mg/d, and increased to 50 mg/d at 4 weeks while other antihypertensive medications were withdrawn to maintain constant mean BP. Phase‐contrast cardiac magnetic resonance imaging of the ascending aorta was performed in 30 participants at baseline and after 6 months of spironolactone treatment to measure aortic pulsatility, distensibility, and pulse wave velocity. Pulse wave velocity decreased (6.3±2.3 m/s to 4.5±1.8 m/s, P<0.001) and pulsatility and distensibility increased (15.9%±5.3% to 22.1%±7.9%, P<0.001; and 0.28%±0.10%/mm Hg to 0.40%±0.14%/mm Hg, P<0.001, respectively) following 6 months of spironolactone.

Conclusions

Our results suggest that spironolactone improves aortic properties in resistant hypertension independently of BP, which may support the hypothesis of an effect of aldosterone on the arterial wall. A larger prospective study is needed to confirm our findings.

Racial disparities and cardiovascular disease: One size fits all approach?

BACKGROUND

Despite recent advancements in prevention, treatment, and management options, cardiovascular diseases contribute to one of the leading causes of morbidity and mortality. Several studies highlight the compelling evidence for the existence of healthcare inequities and disparities in the treatment and management control of cardiovascular diseases.

AIMS

To explore the role of racial disparities in the treatment of various cardiovascular diseases, highlighting the role of socioeconomic and cultural factors, and ultimately postulate solutions to eliminate the disparities.

METHODS

A comprehensive review of the literature was conducted using appropriate keywords on search engines of SCOPUS, Wiley, PubMed, and SAGE Journals.

CONCLUSION

By continued research to eliminate healthcare inequalities, there exists a potential to improve health-related outcomes in minority populations.

Hyperkalemia and management of renin-angiotensin-aldosterone system inhibitors in chronic heart failure with reduced ejection fraction: A systematic review

INTRODUCTION AND OBJECTIVES

Renin-angiotensin-aldosterone system inhibitors (RAASi) are the cornerstone of treatment of heart failure with reduced ejection fraction (HFrEF). RAASi optimization in real-life care is challenged by hyperkalemia, a potentially fatal adverse event, which can necessitate downtitration or discontinuation of RAASi and negatively impact survival in HFrEF. The literature on this problem is sparse. We performed a systematic review of studies on HFrEF to investigate the prevalence, incidence, and risk factors of hyperkalemia, RAASi prescription rates, frequency of RAASi downtitration or discontinuation due to hyperkalemia, and the potential negative effect of the latter on prognosis.

METHODS

We conducted a MEDLINE (PubMed) search including observational and interventional studies published between January 1987 and May 2018.

RESULTS

A total of 30 observational and 18 interventional studies were included in the review. The incidence of hyperkalemia reported was between 0% and 63% in observational studies and was between 0% and 30% in clinical trials. Risk factors for hyperkalemia included RAASi prescription, older age, diabetes, and chronic kidney disease. In real-life studies, RAASi were downtitrated or discontinued in 3-22% of HFrEF patients; hyperkalemia was the reported cause in 5% of cases. No reports were found on the impact on prognosis of RAASi downtitration or discontinuation due to hyperkalemia.

CONCLUSIONS

Hyperkalemia and RAASi downtitration or discontinuation are frequent, particularly in real-life HFrEF studies. Further research is needed to clarify the role of RAASi downtitration or discontinuation due to hyperkalemia and to assess its long-term prognostic impact in HFrEF patients.

Exploring Biologic Predictors Response Disparities to Atypical Antipsychotics among Blacks: A Quasi-Systematic Review

Purpose

Management of schizophrenia among Blacks in the United States is affected by persistent disparities. This review explored response to atypical antipsychotics among Blacks compared with other groups to assess systematic variation that may contribute to disparities.

Methods

We conducted a quasi-systematic review of studies reporting response to atypical antipsychotics among Blacks compared with other groups, including effects of genetic variation.

Results

Of 48 identified research articles, 29 assessed differences in outcomes without inclusion of genetic variation and 20 explored effects of genetic variation; of note: one article included both types of data. Analysis of the 29 papers with clinical outcomes only suggests that while data on efficacy and risk of movement disorders were heterogeneous, findings indicate increased risk of metabolic effects and neutropenia among Blacks. Of the 20 articles exploring effects of genetic variation, allelic or genotypic variations involving several genes were associated with altered efficacy or safety among Blacks but not Whites, including risk of decreased response involving variation in DRD4 and DRD1, and improved efficacy associated with variants in DRD2, COMT, and RGS4. Others showed significant improvement in treatment response only among Whites, including variation in DTNBP1, DRD4, and GNB3.

Conclusions

The current analysis can help tailor management among Blacks using an atypical antipsychotic. Heterogeneity in genetic variation effects and response allele frequency suggests that pharmacogenetics approaches for atypical antipsychotics will need to explicitly incorporate race and ethnicity.

Correlates of Self-Care Behaviors in Adults With Type 2 Diabetes and Comorbid Heart Failure

PURPOSE

The purpose of this study was to describe sociodemographic, clinical, and psychosocial correlates of diabetes self-care behaviors in adults with type 2 diabetes mellitus (T2D) and comorbid heart failure (HF).

METHOD

Baseline data of 180 participants from a clinical trial that tested a 6-month integrated self-care intervention for persons with comorbid HF and T2D were analyzed. Correlational bivariate and multiple logistic regression analyses were performed to examine correlates of diabetes self-care behaviors.

RESULT

Participants had a mean age of 58 ± 11years; the majority were male (n = 118, 66%) and African American (n = 119, 66%). Number of comorbidities >2 (P < .001), having more than a high school education (P < .05), and African American ethnicity (P < .05) predicted better exercise, self-monitoring blood glucose (SMBG), and foot care behaviors, respectively. The use of an aldosterone inhibitor (P < .05) predicted worse exercise performance, higher Charlson Comorbidity Index scores (P < .01) predicted worse SMBG, and treatment with diet plus medication (P < .05) and dyslipidemia (P < .001) predicted worse foot care.

CONCLUSION

Findings from this study provide new insights into the complex self-care requirements for T2D patients with comorbid HF. Integrated self-care interventions are clearly warranted in persons living with multiple chronic conditions for optimal health outcomes and the prevention of complications. Our sample of predominately African American men showed they had better T2D self-care behaviors than whites than previously reported. Additional research is needed to determine racial and gender differences on health outcomes in persons with T2D and comorbid HF.

Incidence, predictors and clinical management of hyperkalaemia in new users of mineralocorticoid receptor antagonists

BACKGROUND

Concerns for hyperkalaemia limit the use of mineralocorticoid receptor antagonists (MRAs). The frequency of MRA-associated hyperkalaemia in real-world settings and the extent of subsequent MRA discontinuation are poorly quantified.

METHODS AND RESULTS

Observational study including all Stockholm citizens initiating MRA therapy during 2007-2010. Hyperkalaemias were identified from all potassium (K+ ) measurements in healthcare. MRA treatment lengths and dosages were obtained from complete collection of pharmacy dispensations. We assessed the 1-year incidence and clinical hyperkalaemia predictors, and quantified drug prescription changes after an episode of hyperkalaemia. Overall, 13 726 new users of MRA were included, with median age of 73 years, 53% women and median plasma K+ of 3.9 mmol/L. Within a year, 18.5% experienced at least one detected hyperkalaemia (K+  > 5.0 mmol/L), the majority within the first 3 monthsnthsnthsnthsnths of therapy. As a comparison, hyperkalaemia was detected in 6.4% of propensity-matched new beta-blocker users. Chronic kidney disease (CKD), older age, male sex, heart failure, peripheral vascular disease, diabetes and concomitant use of angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, beta-blockers and diuretics were associated with increased hyperkalaemia risk. After hyperkalaemia, 47% discontinued MRA and only 10% reduced the prescribed dose. Discontinuation rates were higher after moderate/severe (K+  > 5.5 mmol/L) and early in therapy (<3 months from initiation) hyperkalaemias. CKD participants carried the highest risk of MRA discontinuation in adjusted analyses. When MRA was discontinued, most patients (76%) were not reintroduced to therapy during the subsequent year.

CONCLUSION

Among real-world adults initiating MRA therapy, hyperkalaemia was very common and frequently followed by therapy interruption, especially among participants with CKD.

Racial Differences in Characteristics and Outcomes of Patients With Heart Failure and Preserved Ejection Fraction in the Treatment of Preserved Cardiac Function Heart Failure Trial

Background:

Black patients have been shown to have different baseline characteristics and outcomes compared with nonblack patients in cohort studies. However, few studies have focused on heart failure (HF) with preserved ejection fraction (HFpEF) patients. We aimed to determine the difference in cardiovascular outcomes in black and nonblack patients with HFpEF and to determine the relative efficacy and safety of spironolactone in black and nonblack patients.

Methods and Results:

Patients with HFpEF, randomized to spironolactone versus placebo in the TOPCAT trial (Treatment of Preserved Cardiac Function Heart Failure With an Aldosterone Antagonist) in North and South America, were grouped according to self-described black and nonblack race. Black HFpEF patients (n=302) were younger and were more likely to have diabetes mellitus and hypertension than nonblack patients but had similar HFpEF severity. Black patients had higher risk for the primary outcome (hazard ratio [HR], 1.34; 95% confidence interval, 1.06–1.71; P =0.02) and first HF hospitalization (HR, 1.51; 95% confidence interval, 1.167–1.97; P =0.002)], but no significant difference in cardiovascular mortality risk (HR, 0.78; 95% confidence interval, 0.51–1.20; P =0.326). In black and nonblack patients, randomization to spironolactone conferred similar efficacy in the primary outcome (HR, 0.83 versus 0.79; P for interaction=0.49), HF hospitalization (HR, 0.67 versus 0.82; P for interaction=0.76), and cardiovascular mortality ( P for interaction=0.19). The risk of hyperkalemia and worsening renal function with spironolactone and study drug adherence were also similar.

Conclusions:

Black patients with HFpEF have a higher HF hospitalization risk than nonblack patients, but spironolactone is similarly effective and safe in both groups.

Clinical Trial Registration:

URL: https://www.clinicaltrials.gov . Unique identifier: NCT00094302.

N-terminal pro-B-type natriuretic peptide and prognosis in Caucasian vs. Asian patients with heart failure

Aims

N‐terminal pro‐B‐type natriuretic peptide (NT‐proBNP) is the most frequently used biomarker in heart failure (HF), but its prognostic utility across ethnicities is unclear.

Methods and results

This study included 546 Caucasians with HF from the Coordinating Study Evaluating Outcomes of Advising and Counseling in Heart Failure and 578 Asians with HF from the Singapore Heart Failure Outcomes and Phenotypes study. NT‐proBNP was measured at discharge after HF hospitalization. The studied outcome was a composite of all‐cause mortality and HF hospitalization at 18 months. Compared with Caucasian patients, Asian patients were younger (63 ± 12 vs. 71 ± 11 years); less often female (26% vs. 39%); and had lower body mass index (26 vs. 27 kg/m²), better renal function (61 ± 37 vs. 54 ± 20 mL/min/1.73 m²), lower rates of atrial fibrillation (25% vs. 46%), strikingly higher rates of diabetes (59% vs. 30%), and higher rates of hypertension (76% vs. 44%). Despite these clear inter‐group differences in individual drivers of NT‐proBNP, average levels were similar in Asians [2709 (1350, 6302) pg/mL] and Caucasians [2545 (1308, 5484) pg/mL] (P = 0.514). NT‐proBNP was strongly associated with outcome [hazard ratio 1.28 (per doubling), 95% confidence interval 1.18–1.39, P < 0.001], regardless of ethnicity (P_interaction = 0.719). NT‐proBNP was similarly associated with outcome in HF with reduced and preserved ejection fraction in Asian (P_interaction = 0.776) and Caucasian patients (P_interaction = 0.558).

Conclusions

NT‐proBNP has similar prognostic performance in Asians and Caucasians with HF despite ethnic differences in known clinical determinants of plasma NT‐proBNP.

Pharmacological reasons that may explain why randomized clinical trials have failed in acute heart failure syndromes

Acute heart failure (AHF) represents a clinical challenge as it encloses a heterogeneous group of syndromes (AHFS) with different pathophysiology, clinical presentations, prognosis and response to therapy. In the last 25years multiple therapeutic targets have been identified and numerous new drugs were evaluated but, up to now, all failed to demonstrate a consistent benefit on clinical outcomes. Moreover, a repeated finding has been the poor correlation between the encouraging results of preclinical and early clinical trials and the lack of effect on outcomes observed in phase III trials. We review several possible pharmacological reasons that may explain the lack of success to develop new drugs and the pharmacological challenges to overcome in the future to develop new more effective and safer drugs for the treatment of AHFS.

SPIRONOLACTONE FOR NONRESOLVING CENTRAL SEROUS CHORIORETINOPATHY: A RANDOMIZED CONTROLLED CROSSOVER STUDY

This study is a randomized controlled crossover study evaluating the effect of spironolactone, a mineralocorticoid receptor antagonist for the treatment of nonresolving central serous chorioretinopathy. Spironolactone significantly reduced both serous retinal detachment and choroidal thickness as compared with placebo. Larger clinical trials are needed to confirm these promising results.

To evaluate the effect of spironolactone, a mineralocorticoid receptor antagonist, for nonresolving central serous chorioretinopathy.

Spirolactone provides protection from renal fibrosis by inhibiting the endothelial-mesenchymal transition in isoprenaline-induced heart failure in rats

Background

Fibrosis results in excessive accumulation of extracellular matrix proteins, collagen component alteration, and abnormalities in structure and is partly derived from a process called the endothelial–mesenchymal transition involving transforming growth factor β (TGF-β). We investigated whether spironolactone, an aldosterone receptor blocker, attenuated isoprenaline (Iso)-induced heart failure in rats and also studied the mechanism for the same.

Methods

Sprague–Dawley rats were subcutaneously injected with Iso to induce heart failure, which promoted renal fibrosis; rats with spironolactone treatment were given a gavage of spironolactone (30 or 60 mg/kg/d, for 21 days). Cardiac function and fibrosis indices were measured. Pathological alterations and expression of Type I and III collagen, α-smooth muscle actin, cluster of differentiation-31, and TGF-β were examined.

Results

In Iso-induced heart failure in rats, spironolactone significantly improved cardiac function and decreased myocardial fibrosis, reduced collagen fibrous proliferation in kidney, reduced expression of Type I and III collagen, increased the expression of cluster of differentiation-31, and decreased the expression of α-smooth muscle actin and TGF-β.

Conclusion

Spironolactone may prevent renal fibrosis by inhibiting the endothelial–mesenchymal transition.

Circulating Procollagen Type III N-Terminal Peptide and Mortality Risk in African Americans With Heart Failure

BACKGROUND

Procollagen type III N-terminal peptide (PIIINP) is a biomarker of cardiac fibrosis that is associated with heart failure prognosis in whites. Its prognostic significance in African Americans is unknown. We sought to determine whether PIIINP is associated with outcomes in African Americans with heart failure.

METHODS AND RESULTS

Blood was collected from 138 African Americans with heart failure for determining PIIINP and genetic ancestry, and patients were followed prospectively for death or hospitalization for heart failure. PIIINP was inversely correlated with West African ancestry (R(2) = 0.061; P = .010). PIIINP > 4.88 ng/mL was associated with all-cause mortality on univariate (hazard ratio [HR] 4.9, 95% confidence interval [CI] 2.2-11.0; P < .001) and multivariate (HR 5.8; 95% CI 1.9-17.3; P = .002) analyses over a median follow-up period of 3 years. We also observed an increased risk for the combined outcome of all-cause mortality or hospitalization for heart failure with PIIINP > 4.88 ng/mL on univariate (HR 2.6, 95% CI 1.6-5.0; P < .001) and multivariate (HR 2.4, 95% CI 1.2-4.7; P = .016) analyses.

CONCLUSIONS

High circulating PIIINP is associated with poor outcomes in African Americans with chronic heart failure, suggesting that PIIINP may be useful in identifying African Americans who may benefit from additional therapy to combat fibrosis as a means of improving prognosis.

Effect of mineralocorticoid receptor blockade on hippocampal-dependent memory in adults with obesity

OBJECTIVE

The hippocampus is crucial for paired-associate learning. Obesity is associated with increased mineralocorticoid receptor (MR) activity in peripheral and possibly central tissues, decreased hippocampal size in humans, and impaired hippocampal learning in rodents. The MR is expressed in hippocampal neurons, and MR blockade improves hippocampal learning in obese animals. The goal of the study was to determine whether MR blockade would modulate paired-associate learning in men and women with obesity.

METHODS

Men and women ages 20-61 years with BMI between 30-45 kg/m(2) were randomly assigned to placebo (n = 11; 7 women) or 50 mg spironolactone daily (n = 12; 7 women) for six weeks. At baseline and post-treatment, subjects underwent a clinical and hormonal evaluation. They also underwent a computerized task that assesses paired-associate learning and has been shown by functional magnetic resonance imaging to activate the hippocampus.

RESULTS

In an ANCOVA model that adjusted for baseline paired-associate learning, age, and race, spironolactone treatment was associated with a significant (P = 0.043) improvement in hippocampal memory as compared to placebo treatment.

CONCLUSIONS

Our findings demonstrate, for the first time, that blocking MR with chronic, low-dose spironolactone treatment improves paired-associate learning in individuals with obesity, suggesting that MR activation contributes to hippocampal memory modulation in humans.

Cardiovascular actions of mineralocorticoid receptor antagonists in patients with chronic kidney disease: A systematic review and meta-analysis of randomized trials

INTRODUCTION

The safety and actions of mineralocorticoid receptor antagonists on surrogate markers of cardiovascular disease as well as major patient level cardiovascular end-points in patients with chronic kidney disease are unclear.

METHODS

MEDLINE, EMBASE, Trip Database, Cochrane Central Register of Controlled Trials, Cochrane Renal Group specialized register, Current Controlled Trials and clinicaltrials.gov were searched for relevant trials.

RESULTS

Twenty-nine trials (1581 patients) were included. Overall, mineralocorticoid receptor antagonists lowered both systolic and diastolic blood pressure (-5.24, 95% confidence interval (CI) -8.65, -1.82 mmHg; p=0.003 and -1.96, 95% CI -3.22, -0.69 mmHg; p=0.002 respectively). There were insufficient data to perform a meta-analysis of other cardiovascular effects. However, a systematic review of the studies included suggested a consistent improvement in surrogate markers of cardiovascular disease. Overall, the use of mineralocorticoid receptor antagonists was associated with an increased serum potassium (0.23, 95% CI 0.13, 0.33 mmol/l; p<0.0001) and higher risk ratio (1.76, 95% CI 1.20, 2.57; p=0.001) of hyperkalemia. Data on long-term cardiovascular outcomes and mortality were not available in any of the trials.

CONCLUSIONS

The long-term effects of mineralocorticoid receptor antagonists on cardiovascular events, mortality and safety need to be established.

Aldosterone blockade in CKD: emphasis on pharmacology

Besides its epithelial effect on sodium retention and potassium excretion in the distal tubule, aldosterone promotes inflammation and fibrosis in the heart, kidneys, and blood vessels. As glomerular filtration rate falls, aldosterone is inappropriately elevated relative to extracellular fluid expansion. In addition, studies in CKD patients on angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, and/or direct renin inhibitors have shown that aldosterone levels paradoxically rise in approximately 30% to 40% of patients on these renin-angiotensin system-blocking drugs. Hence, there is interest in using mineralocorticoid receptor blockers that directly target the inflammatory and fibrotic effects of aldosterone in CKD patients. This interest, however, is tempered by a number of unresolved issues, including the safety of using such drugs in advanced CKD and ESRD populations, and the potential for differences in drug efficacy according to race and ethnicity of patient populations. A better understanding of mineralocorticoid receptor blocker pharmacology should help inform future research directions and clinical practice decisions as to how best to use these agents in CKD.

Mineralocorticoid receptor antagonist in heart failure: Past, present and future perspectives

Aldosterone is involved in various deleterious effects on the cardiovascular system, including sodium and fluid retention, myocardial fibrosis, vascular stiffening, endothelial dysfunction, catecholamine release and stimulation of cardiac arrhythmias. Therefore, aldosterone receptor blockade may have several potential benefits in patients with cardiovascular disease. Mineralocorticoid receptor antagonists (MRAs) have been shown to prevent many of the maladaptive effects of aldosterone, in particular among patients with heart failure (HF). Randomized controlled trials have demonstrated efficacy of MRA in heart failure with reduced ejection fraction, both in patients with NYHA functional classes III and IV and in asymptomatic and mildly symptomatic patients (NYHA classes I and II). Recent data in patients with heart failure with preserved ejection fraction are encouraging. MRA could also have anti-arrhythmic effects on atrial and ventricular arrhythmias and may be helpful in patient ischemic heart disease through prevention of myocardial fibrosis and vascular damage. This article aims to discuss the pathophysiological effects of aldosterone in patients with cardiovascular disease and to review the current data that support the use of MRA in heart failure.