Long-Term Effects of Low-Dose Spironolactone on Chronic Dialysis Patients: A Randomized Placebo-Controlled Study

Effect of spironolactone on survival in patients undergoing maintenance hemodialysis

BACKGROUND

Previous studies have reported inconsistent results regarding the advantages or disadvantages of spironolactone use in patients undergoing hemodialysis (HD). This study aimed to evaluate survival according to the use of spironolactone in a large sample of patients undergoing maintenance HD.

METHODS

This retrospective study used laboratory and clinical data from the national HD Quality Assessment Program and claims data. The participants of the quality assessment program were patients who had been undergoing maintenance HD for ≥ 3 months, patients undergoing HD at least twice a week. Patients with no spironolactone prescription during the assessment periods were designated as the control group. Patients with one or more prescriptions of spironolactone during the assessment periods were assigned to the SPR group.

RESULTS

The number of patients in the control and SPR groups were 54,588 and 315, respectively. The 5-year survival rates were 69.1% and 59.1% in the control and SPR groups, respectively (P < 0.001). Cox regression analyses showed that the hazard ratio in the SPR group was 1.34 (P < 0.001) in univariate analysis and 1.13 (P = 0.249) in multivariable analysis. Univariate Cox-regression analysis showed a better patient survival rate in the control group than in the SPR group; however, multivariable analyses showed similar patient survival rates between the two groups.

CONCLUSION

This study showed no difference in survival between patients undergoing HD with and without spironolactone use.

Mineralocorticoid receptor antagonists and atrial fibrillation: a meta-analysis of clinical trials

BACKGROUND AND AIMS

Mineralocorticoid receptor antagonists (MRAs) improve cardiovascular outcomes in a variety of settings. This study aimed to assess whether cardioprotective effects of MRAs are modified by heart failure (HF) and atrial fibrillation (AF) status and to study their impact on AF events.

METHODS

MEDLINE, Embase, and Cochrane Central databases were searched to 24 March 2023 for randomized controlled trials evaluating the efficacy of MRAs as compared with placebo or usual care in reducing cardiovascular outcomes and AF events in patients with or at risk for cardiovascular diseases. Random-effects models and interaction analyses were used to test for effect modification.

RESULTS

Meta-analysis of seven trials (20 741 participants, mean age: 65.6 years, 32% women) showed that the efficacy of MRAs, as compared with placebo, in reducing a composite of cardiovascular death or HF hospitalization remains consistent across patients with HF [risk ratio = 0.81; 95% confidence interval (CI): 0.67-0.98] and without HF (risk ratio = 0.84; 95% CI: 0.75-0.93; interaction P = .77). Among patients with HF, MRAs reduced cardiovascular death or HF hospitalization in patients with AF (hazard ratio = 0.95; 95% CI: 0.54-1.66) to a similar extent as in those without AF (hazard ratio = 0.82; 95% CI: 0.63-1.07; interaction P = .65). Pooled data from 20 trials (21 791 participants, mean age: 65.2 years, 31.3% women) showed that MRAs reduce AF events (risk ratio = 0.76; 95% CI: 0.67-0.87) in both patients with and without prior AF.

CONCLUSIONS

Mineralocorticoid receptor antagonists are similarly effective in preventing cardiovascular events in patients with and without HF and most likely retain their efficacy regardless of AF status. Mineralocorticoid receptor antagonists may also be moderately effective in preventing incident or recurrent AF events.

Overview of research progress on the association of dietary potassium intake with serum potassium and survival in hemodialysis patients, does dietary potassium restriction really benefit hemodialysis patients?

For the general population, increasing potassium intake can reduce the incidence of cardiovascular and cerebrovascular diseases. However, since hyperkalemia is a common and life-threatening complication in maintenance hemodialysis patients, which can increase the risk of malignant arrhythmia and sudden death, the current mainstream of management for hemodialysis patients is dietary potassium restriction in order to prevent hyperkalemia. Hemodialysis patients are usually advised to reduce dietary potassium intake and limit potassium-rich fruits and vegetables, but there is limited evidence to support this approach can reduce mortality and improve quality of life. There is still no consistent conclusion on the association between dietary potassium intake and serum potassium and survival in hemodialysis patients. According to the current small observational studies, there was little or even no association between dietary potassium intake and serum potassium in hemodialysis patients when assurance of adequate dialysis and specific dietary patterns (such as the plant-based diet mentioned in the article) are being followed, and excessive dietary potassium restriction may not benefit the survival of hemodialysis patients. Additionally, when assessing the effect of diet on serum potassium, researchers should not only focus on the potassium content of foods, but also consider the type of food and the content of other nutrients. However, more large-scale, multi-center clinical trials are required to provide high-quality evidence support. Besides, further research is also needed to determine the optimal daily potassium intake and beneficial dietary patterns for hemodialysis patients.

Diagnosis and treatment of hypertension in dialysis patients: a systematic review

In patients with end-stage renal disease (ESRD) undergoing dialysis, hypertension is common but often inadequately controlled. The prevalence of hypertension varies widely among studies because of differences in the definition of hypertension and the methods of used to measure blood pressure (BP), i.e., peri-dialysis or ambulatory BP monitoring (ABPM). Recently, ABPM has become the gold standard for diagnosing hypertension in dialysis patients. Home BP monitoring can also be a good alternative to ABPM, emphasizing BP measurement outside the hemodialysis (HD) unit. One thing for sure is pre- and post-dialysis BP measurements should not be used alone to diagnose and manage hypertension in dialysis patients. The exact target of BP and the relationship between BP and all-cause mortality or cause-specific mortality are unclear in this population. Many observational studies with HD cohorts have almost universally reported a U-shaped or even an L-shaped association between BP and all-cause mortality, but most of these data are based on the BP measured in HD units. Some data with ABPM have shown a linear association between BP and mortality even in HD patients, similar to the general population. Supporting this, the results of meta-analysis have shown a clear benefit of BP reduction in HD patients. Therefore, further research is needed to determine the optimal target BP in the dialysis population, and for now, an individualized approach is appropriate, with particular emphasis on avoiding excessively low BP. Maintaining euvolemia is of paramount importance for BP control in dialysis patients. Patient heterogeneity and the lack of comparative evidence preclude the recommendation of one class of medication over another for all patients. Recently, however, β-blockers could be considered as a first-line therapy in dialysis patients, as they can reduce sympathetic overactivity and left ventricular hypertrophy, which contribute to the high incidence of arrhythmias and sudden cardiac death. Several studies with mineralocorticoid receptor antagonists have also reported promising results in reducing mortality in dialysis patients. However, safety issues such as hyperkalemia or hypotension should be further evaluated before their use.

Epidemiology, Pathophysiology, and Clinical Perspectives of Intradialytic Hypertension

BACKGROUND

Individuals with end-stage renal disease on chronic hemodialysis (HD) may encounter numerous HD-associated complications, including intradialytic hypertension (IDHYPER). Although blood pressure (BP) follows a predictable course in the post-HD period, BP levels during the session may vary across the individuals. Typically, a decline in BP is noted during HD, but a significant proportion of patients exhibit a paradoxical elevation.

SUMMARY

Several studies have been conducted to understand the complexity of IDHYPER, but much remains to be elucidated in the future. This review article aimed to present the current evidence regarding the proposed definitions, the pathophysiologic background, the extent and clinical implications of IDHYPER, as well as the possible therapeutic options that have emerged from clinical studies.

KEY MESSAGES

IDHYPER is noted in approximately 15% of individuals undergoing HD. Several definitions have been proposed, with a systolic BP rise >10 mm Hg from pre- to post-dialysis in the hypertensive range in at least four out of six consecutive HD treatments being suggested by the latest Kidney Disease: Improving Global Outcomes. Concerning its pathophysiology, extracellular fluid overload is a crucial determinant, with endothelial dysfunction, sympathetic nervous system overdrive, renin-angiotensin-aldosterone system activation, and electrolyte alterations being important contributors. Although its association with ambulatory BP in the interdialytic period is controversial, IDHYPER is associated with adverse cardiovascular events and mortality. Moving to its management, the antihypertensive drugs of choice should ideally be nondialyzable with proven cardiovascular and mortality benefits. Finally, rigorous clinical and objective assessment of extracellular fluid volume is essential. Volume-overloaded patients should be instructed about the importance of sodium restriction, while physicians ought to alter HD settings toward a greater dry weight reduction. The use of a low-sodium dialysate and isothermic HD could also be considered on a case-by-case basis since no randomized evidence is currently available.

Research Progress on the Efficacy and Safety of Spironolactone in Reversing Left Ventricular Hypertrophy in Hemodialysis Patients

The mineralocorticoid receptor antagonist spironolactone has been shown to improve cardiac function and reverse left ventricular hypertrophy in heart failure patients, but there are no consistent findings on the efficacy and safety in hemodialysis patients. Abnormal aldosterone secretion plays a critical role in the formation of left ventricular hypertrophy. Because of the existence of "aldosterone escape", the routine use of angiotensin-converting enzyme inhibitors/angiotensin receptor blockers does not completely inhibit aldosterone secretion. Low-dose spironolactone (25 mg/d) has been found in small-sample clinical studies to have a significant positive impact with respect to decreasing left ventricular mass index, increasing left ventricular ejection fraction, reversing left ventricular hypertrophy, and improving cardiovascular function while still being safe. More prospective multicenter clinical trials with large sample sizes are needed, however, to provide convincing evidence.

Emerging vascular cell-specific roles for mineralocorticoid receptor: implications for understanding sex differences in cardiovascular disease

As growing evidence implicates extrarenal mineralocorticoid receptor (MR) in cardiovascular disease (CVD), recent studies have defined both cell- and sex-specific roles. MR is expressed in vascular smooth muscle (SMC) and endothelial cells (ECs). This review integrates published data from the past 5 years to identify novel roles for vascular MR in CVD, with a focus on understanding sex differences. Four areas are reviewed in which there is recently expanded understanding of the cell type- or sex-specific role of MR in 1) obesity-induced microvascular endothelial dysfunction, 2) vascular inflammation in atherosclerosis, 3) pulmonary hypertension, and 4) chronic kidney disease (CKD)-related CVD. The review focuses on preclinical data on each topic describing new mechanistic paradigms, cell type-specific mechanisms, sexual dimorphism if addressed, and clinical implications are then considered. New data support that MR drives vascular dysfunction induced by cardiovascular risk factors via sexually dimorphic mechanisms. In females, EC-MR contributes to obesity-induced endothelial dysfunction by regulating epithelial sodium channel expression and by inhibiting estrogen-induced nitric oxide production. In males with hyperlipidemia, EC-MR promotes large vessel inflammation by genomic regulation of leukocyte adhesion molecules, which is inhibited by the estrogen receptor. In pulmonary hypertension models, MRs in EC and SMC contribute to distinct components of disease pathologies including pulmonary vessel remodeling and RV dysfunction. Despite a female predominance in pulmonary hypertension, sex-specific roles for MR have not been explored. Vascular MR has also been directly implicated in CKD-related vascular dysfunction, independent of blood pressure. Despite these advances, sex differences in MR function remain understudied.

The effects of mineralocorticoid receptor antagonists on cardiovascular outcomes in patients with end-stage renal disease and heart failure

AIMS

Mineralocorticoid receptor antagonists (MRAs) have been shown to provide survival benefits in patients with heart failure; however, MRA use in patients with chronic kidney disease has been limited by safety concerns. The effects of MRAs on outcomes in patients with end-stage renal disease (ESRD) and heart failure remain unknown. The aim of this study was to evaluate the effects of MRAs on cardiovascular outcomes in patients with heart failure under maintenance dialysis in a real-world setting.

METHODS AND RESULTS

A retrospective cohort study was conducted by collecting data from the Taiwan National Health Insurance Research Database (NHIRD). Patients diagnosed with heart failure and ESRD and who started maintenance dialysis between 1 January 2001 and 31 December 2013 were identified. Patients were grouped according to MRA prescription. The outcomes of interest included cardiovascular (CV) death, hospitalization for heart failure (HHF), all-cause mortality, acute myocardial infarction (AMI), ischaemic stroke, any coronary revascularization procedures, and new-onset hyperkalaemia. Propensity score matching was performed at a 1:3 ratio between MRA users and non-users to minimize selection bias. A total of 50 872 patients who satisfied our inclusion and exclusion criteria were identified. After 1:3 matching, 2176 patients were included in the MRA group, and 6528 patients were included in the non-MRA group. The risk of CV death was significantly lower among patients who received MRAs than those who did not (hazard ratio [HR] 0.88, 95% confidence interval [CI] 0.80-0.95), as was the risk of all-cause mortality (HR 0.88, 95% CI 0.83-0.94). Reductions in the risks of CV death and all-cause mortality were more prominent among patients undergoing haemodialysis and those with coronary artery disease.

CONCLUSIONS

In patients undergoing regular dialysis who are diagnosed with heart failure, the use of MRAs is associated with lower risks of all-cause mortality and CV death. The benefits of MRA treatment in heart failure may persist in patients with ESRD. Further investigations through randomized controlled trials are needed to assess the efficacy and safety of MRAs in this high-risk population.

Mineralocorticoid receptor antagonists for cardioprotection in chronic kidney disease: a step into the future

Chronic kidney disease (CKD) and cardiovascular disease (CVD) share major risk factors and mechanistic pathways for progression. Furthermore, either decreased glomerular filtration rate or increased albuminuria are major risk factors for cardiovascular events. Evidence from previous renal outcome trials in patients with proteinuric CKD showed that angiotensin-converting-enzyme inhibitors (ACEIs) and angiotensin-II receptor blockers (ARBs) effectively slow CKD progression, establishing these agents as fundamental CKD pharmacologic treatments. However, in all these trials and subsequent meta-analyses, ACEIs and ARBs did not significantly reduce cardiovascular events or mortality, indicating a high residual risk for CVD progression in individuals with CKD. In contrast to the above, several outcome trials with old and novel mineralocorticoid receptor-antagonists (MRAs) clearly suggest that these agents, apart from nephroprotection, offer important cardioprotection in this population. This article is an overview of previous and recent evidence on the effects of MRAs on cardiovascular outcomes in patients with CKD attempting to highlight a pathway able to improve both cardiovascular and renal prognosis in this population.

Association of Mineralocorticoid Receptor Antagonists With the Mortality and Cardiovascular Effects in Dialysis Patients: A Meta-analysis

Whether Mineralocorticoid receptor antagonists (MRA) reduce mortality and cardiovascular effects of dialysis patients remains unclear. A meta-analysis was designed to investigate whether MRA reduce mortality and cardiovascular effects of dialysis patients, with a registration in INPLASY (INPLASY2020120143). The meta-analysis revealed that MRA significantly reduced all-cause mortality (ACM) and cardiovascular mortality (CVM). Patients receiving MRA presented improved left ventricular mass index (LVMI) and left ventricular ejection fraction (LVEF), decreased systolic blood pressure (SBP) and diastolic blood pressure (DBP). There was no significant difference in the serum potassium level between the MRA group and the placebo group. MRA vs. control exerts definite survival and cardiovascular benefits in dialysis patients, including reducing all-cause mortality and cardiovascular mortality, LVMI, and arterial blood pressure, and improving LVEF. In terms of safety, MRA did not increase serum potassium levels for dialysis patients with safety. Systematic Review Registration: (https://inplasy.com/inplasy-protocol-1239-2/), identifier (INPLASY2020120143).

Effect of spironolactone on vascular stiffness in hemodialysis patients: a randomized crossover trial

Background

The role of spironolactone treatment in hemodialysis patients is debated, but a survival benefit is suggested. Mineralocorticoids and chronic kidney disease have been linked to cardiovascular fibrosis. Therefore, we hypothesized that spironolactone would affect vascular stiffness, cardiac systolic, and diastolic function in hemodialysis patients.

Methods

This was a randomized crossover study in hemodialysis patients supplemented with an echocardiographic case series. All outcomes reported here were secondary in the trial and were assessed without blinding. Block randomization and allocation determined treatment order. Participants received 50 mg spironolactone daily for 12 weeks and untreated observation for another 12 weeks. Pulse wave velocity (PWV) was measured before and after treatment and observation. Doppler-echocardiography was conducted before and after treatment. Systemic arterial compliance indexed to body surface area (SACi), left ventricular ejection fraction (LVEF), the peak early diastolic mitral inflow velocity (E), the peak late diastolic mitral inflow velocity (A), and the peak early diastolic myocardial lengthening velocity (E') were measured. E/A and E/E' were then calculated. Statistical analyses were conducted per protocol. A generalized linear mixed model with random participant effects was used for PWV. The Wilcoxon signed-rank test was used for echocardiographic variables.

Results

Thirty participants were recruited, 18 completed follow-up, and 17 were included in PWV-analyses. Spironolactone treatment showed a tendency toward an increase in PWV of 1.34 (95% confidence interval: -0.11 to 2.78) m/s, which was not statistically significant (P = 0.07). There were no significant changes in any of the other variables (LVEF, E/A, E/E', or SACi).

Conclusions

We found no evidence supporting an effect of 12-week administration of spironolactone 50 mg daily on vascular stiffness, cardiac systolic, or diastolic function in hemodialysis patients.

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.

Left ventricular mass regression, all-cause and cardiovascular mortality in chronic kidney disease: a meta-analysis

Background

Cardiovascular disease is an important driver of the increased mortality associated with chronic kidney disease (CKD). Higher left ventricular mass (LVM) predicts increased risk of adverse cardiovascular outcomes and total mortality, but previous reviews have shown no clear association between intervention-induced LVM change and all-cause or cardiovascular mortality in CKD.

Methods

The primary objective of this meta-analysis was to investigate whether treatment-induced reductions in LVM over periods ≥12 months were associated with all-cause mortality in patients with CKD. Cardiovascular mortality was investigated as a secondary outcome. Measures of association in the form of relative risks (RRs) with associated variability and precision (95% confidence intervals [CIs]) were extracted directly from each study, when reported, or were calculated based on the published data, if possible, and pooled RR estimates were determined.

Results

The meta-analysis included 42 trials with duration ≥12 months: 6 of erythropoietin stimulating agents treating to higher vs. lower hemoglobin targets, 10 of renin-angiotensin-aldosterone system inhibitors vs. placebo or another blood pressure lowering agent, 14 of modified hemodialysis regimens, and 12 of other types of interventions. All-cause mortality was reported in 121/2584 (4.86%) subjects in intervention groups and 168/2606 (6.45%) subjects in control groups. The pooled RR estimate of the 27 trials ≥12 months with ≥1 event in ≥1 group was 0.72 (95% CI 0.57 to 0.90, p = 0.005), with little heterogeneity across studies. Directionalities of the associations in intervention subgroups were the same. Sensitivity analyses of ≥6 months (34 trials), ≥9 months (29 trials), and >12 months (10 trials), and including studies with no events in either group, demonstrated similar risk reductions to the primary analysis. The point estimate for cardiovascular mortality was similar to all-cause mortality, but not statistically significant: RR 0.67, 95% CI 0.39 to 1.16.

Conclusions

These results suggest that LVM regression may be a useful surrogate marker for benefits of interventions intended to reduce mortality risk in patients with CKD.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12882-022-02666-1.

Mineralocorticoid Receptor Antagonist Use and Hard Renal Outcomes in Real-World Patients With Chronic Kidney Disease

BACKGROUND

Real-world evidence about mineralocorticoid receptor antagonist (MRA) use has been limited in chronic kidney disease, particularly regarding its association with hard renal outcomes.

METHODS

In this retrospective cohort study, adult chronic kidney disease outpatients referred to the department of nephrology at an academic hospital between January 2005 and December 2018 were analyzed. The main inclusion criteria were estimated glomerular filtration rate ≥10 and <60 mL/min per 1.73 m² and follow-up ≥90 days. The exposure of interest was MRA use, defined as the administration of spironolactone, eplerenone, or potassium canrenoate. The primary outcome was renal replacement therapy initiation, defined as the initiation of chronic hemodialysis, peritoneal dialysis, or kidney transplantation. A marginal structural model using inverse probability of weighting was applied to account for potential time-varying confounders.

RESULTS

Among a total of 3195 patients, the median age and estimated glomerular filtration rate at baseline were 66 years and 38.4 mL/min per 1.73 m², respectively. During follow-up (median, 5.9 years), 770 patients received MRAs, 211 died, and 478 started renal replacement therapy. In an inverse probability of weighting-weighted pooled logistic regression model, MRA use was significantly associated with a 28%-lower rate of renal replacement therapy initiation (hazard ratio, 0.72 [95% CI, 0.53-0.98]). The association between MRA use and renal replacement therapy initiation was dose-dependent (P for trend <0.01) and consistent across patient subgroups. The incidence of hyperkalemia (>5.5 mEq/L) was somewhat higher in MRA users but not significant (hazard ratio, 1.14 [95% CI, 0.88-1.48]).

CONCLUSIONS

MRA users showed a better renal prognosis across various chronic kidney disease subgroups in a real-world chronic kidney disease population.

Mineralocorticoid Receptor Antagonists-Use in Chronic Kidney Disease

Mineralocorticoid receptor antagonists (MRA) are drugs with a potentially broad spectrum of action. They have been reported to have healing effects in many diseases, such as chronic heart failure, hypertension, or nephrotic syndrome. Numerous studies suggest that mineralocorticoid receptor activation is pathogenic and a progression factor of chronic kidney disease (CKD); however, results of studies on the use of MRA in the treatment of CKD are inconclusive. Current guidelines recommend against the use of MRA in patients with advanced CKD. Although, there is growing interest on their use in this population due to treatment benefits. In this review, we summarize studies which were purposed to evaluate the impact of MRA therapy on CKD patients. Despite many benefits of this treatment e.g., reducing cardiovascular mortality or alleviating proteinuria, steroidal MRA (such as spironolactone or eplerenone) have a low safety profile. They often lead to hyperkalemia complications which are dangerous in patients with CKD, and diabetic nephropathy, especially in hemodialysis patients. Studies on recently developed nonsteroidal MRA showed that they have fewer side effects. In our review, we discuss steroidal and nonsteroidal MRA treatment effects on the estimated glomerular filtration rate (eGFR), proteinuria, the cardiovascular system, and hyperkalemia in CKD patients. We present new content and recent publications in this field.

A Comparison of Hemodialysis and Peritoneal Dialysis in Patients with Cardiovascular Disease

The high prevalence of cardiovascular disease is caused by the traditional cardiovascular risk factors common among end-stage renal disease patients, and nontraditional risk factors attributed to underlying kidney disease, including chronic inflammation, anemia, bone mineral disease, and the dialysis procedure itself. Individualization of the treatment of cardiovascular disease in end-stage renal disease that could impact the underlying mechanisms of the cardiovascular diseases is important to improve outcomes. This article reviews and compares hemodialysis and peritoneal dialysis in association with different cardiovascular diseases affecting dialysis patients, including hypertension, coronary artery disease, myocardial stunning, cardiac arrhythmias, heart failure, and the cardiorenal syndrome.

Systematic Review and Meta-Analysis of Renin-Angiotensin-Aldosterone System Blocker Effects on the Development of Cardiovascular Disease in Patients With Chronic Kidney Disease

Background: Cardiovascular events are one of the most serious complications that increase the risk of mortality and morbidity in pre-dialysis and on-dialysis chronic kidney disease (CKD) patients. Activation of the renin-angiotensin-aldosterone system (RAAS) is considered to contribute to the development of cardiovascular events in these populations. Therefore, several kinds of RAAS blockers have been frequently prescribed to prevent cardiovascular events in patients with CKD; however, their effectiveness remains controversial. This systematic review focuses on whether RAAS blockers prevent cardiovascular events in patients with CKD. Method: PubMed were searched to retrieve reference lists of eligible trials and related reviews. Randomized prospective controlled trials that investigated the effects on cardiovascular events in CKD patients that were published in English from 2010 to 2020 were included. Results: Among 167 identified studies, 11 eligible studies (n = 8,322 subjects) were included in the meta-analysis. The meta-analysis showed that RAAS blockers significantly reduced cardiovascular events in on-dialysis patients with CKD [three studies; odds ratio (OR), 0.52; 95% confidence interval (CI), 0.36 to 0.74; p = 0.0003], but there was no significant difference in pre-dialysis patients with CKD because of the heterogeneity in each study (eight studies). We also investigated the effects of each kind of RAAS blocker on cardiovascular events in CKD patients. Among the RAAS blockers, mineralocorticoid receptor antagonists significantly decreased cardiovascular events in pre-dialysis or on-dialysis patients with CKD (four studies; OR, 0.60; 95%CI, 0.50 to 0.73, p < 0.0001). However, angiotensin receptor blockers did not show significant effects (four studies; OR, 0.65; 95%CI, 0.42 to 1.01; p = 0.0529). The effects of angiotensin converting enzyme inhibitors and direct renin inhibitors on cardiovascular events in patients with CKD could not be analyzed because there were too few studies. Conclusion: Mineralocorticoid receptor antagonists may decrease cardiovascular events in pre-dialysis or on-dialysis patients with CKD.

Efficacy and Safety of Mineralocorticoid Receptor Antagonists in Kidney Failure Patients Treated with Dialysis: A Systematic Review and Meta-Analysis

BACKGROUND AND OBJECTIVES

Patients with kidney failure have a high risk of cardiovascular disease due to cardiac remodeling, left ventricular fibrosis, and hyperaldosteronism, all of which can be potentially mitigated by mineralocorticoid receptor antagonists. However, because of the fear of hyperkalemia, the use of mineralocorticoid receptor antagonists in patients with kidney failure is limited in current clinical practice, and few studies have investigated the efficacy and safety. Thus, we aimed to determine the benefits and side effects of mineralocorticoid receptor antagonists in patients with kidney failure treated with dialysis.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

This is a systematic review and meta-analysis of randomized controlled trials published from 2005 to 2020 that compared the effect of mineralocorticoid receptor antagonists with either placebo or no treatment in patients with kidney failure. Two reviewers independently searched the PubMed, EMBASE, and Cochrane databases for all published studies, extracted data, assessed the risk of bias, and rated the quality of evidence. A meta-analysis was conducted on 14 eligible randomized controlled trials, and a total of 1309 patients were included.

RESULTS

High-quality evidence suggested that mineralocorticoid receptor antagonists are associated with lower cardiovascular mortality (relative risk, 0.41; 95% confidence interval, 0.24 to 0.70; P=0.001) and all-cause mortality (relative risk, 0.44; 95% confidence interval, 0.30 to 0.66; P<0.001), and the risk of hyperkalemia was comparable with that of control group (relative risk, 1.12; 95% confidence interval, 0.91 to 1.36; P=0.29). However, no significant decrease in nonfatal cardiovascular events and stroke was observed, and there was no significant improvement in BP or cardiac performance parameters, including left ventricular ejection fraction and left ventricular mass index.

CONCLUSIONS

Our meta-analysis suggests that mineralocorticoid receptor antagonists might improve clinical outcomes of patients with kidney failure without significant increase in the risk of hyperkalemia.

The cardiovascular-dialysis nexus: the transition to dialysis is a treacherous time for the heart

Chronic kidney disease (CKD) patients require dialysis to manage the progressive complications of uraemia. Yet, many physicians and patients do not recognize that dialysis initiation, although often necessary, subjects patients to substantial risk for cardiovascular (CV) death. While most recognize CV mortality risk approximately doubles with CKD the new data presented here show that this risk spikes to >20 times higher than the US population average at the initiation of chronic renal replacement therapy, and this elevated CV risk continues through the first 4 months of dialysis. Moreover, this peak reflects how dialysis itself changes the pathophysiology of CV disease and transforms its presentation, progression, and prognosis. This article reviews how dialysis initiation modifies the interpretation of circulating biomarkers, alters the accuracy of CV imaging, and worsens prognosis. We advocate a multidisciplinary approach and outline the issues practitioners should consider to optimize CV care for this unique and vulnerable population during a perilous passage.

Cardiovascular Protection With Sodium-Glucose Cotransporter-2 Inhibitors and Mineralocorticoid Receptor Antagonists in Chronic Kidney Disease: A Milestone Achieved

Chronic kidney disease (CKD) and cardiovascular disease are intimately linked. They share major risk factors, including age, hypertension, and diabetes, and common pathogenetic mechanisms. Furthermore, reduced renal function and kidney injury documented with albuminuria are independent risk factors for cardiovascular events and mortality. In major renal outcome trials and subsequent meta-analyses in patients with CKD, ACE (angiotensin-converting enzyme) inhibitors and ARBs (angiotensin II receptor blockers) were shown to effectively retard CKD progression but not to significantly reduce cardiovascular events or mortality. Thus, a high residual risk for cardiovascular disease progression under standard-of-care treatment is still present for patients with CKD. In contrast to the above, several outcome trials with SGLT-2 (sodium-glucose cotransporter-2) inhibitors and MRAs (mineralocorticoid receptor antagonists) clearly suggest that these agents, apart from nephroprotection, offer important cardioprotection in this population. This article discusses existing evidence on the effects of SGLT-2 inhibitors and MRAs on cardiovascular outcomes in patients with CKD that open new roads in cardiovascular protection of this heavily burdened population.

The safety and efficacy of low-dose mineralocorticoid receptor antagonists in dialysis patients: A meta-analysis

INTRODUCTION

Our aim was to evaluate the safety and efficacy of low-dose mineralocorticoid receptor antagonists (MRAs) in dialysis patients.

METHODS

We systematically searched PubMed, EMBASE, and Cochrane libraries for clinical trials on the use of MRAs in dialysis patients. Review Manager 5.3 software was used to analyze relevant data and evaluate the quality of evidence.

RESULTS

We identified nine randomized controlled trials including 1128 chronic dialysis patients. In terms of safety, when hyperkalemia was defined as serum potassium level ≥5.5 mmol/L, low-dose MRAs were significantly associated with hyperkalemia (relative risk [RR] 1.76, 95% confidence intervals [CI] 1.07-2.89, P = .02); however, when hyperkalemia was defined as serum potassium level ≥6.0 mmol/L or serum potassium level ≥6.5 mmol/L, no significant association was observed between low-dose MRAs and hyperkalemia (RR 1.40, 95% CI 0.83-2.37, P = .20; RR 1.98, 95% CI 0.91-4.30, P = .09, respectively). Use of low-dose MRAs can reduce cardiovascular mortality by 54% compared with the control group (0.46, 95% CI 0.28-0.76, P = .003). Similarly, the RR of all-cause mortality for the low-dose MRAs group was 0.48 (95% CI 0.33-0.72, P = .0003).

CONCLUSION

Low-dose MRAs may benefit dialysis patients without significantly increasing moderate to severe hyperkalemia.

Aldosterone antagonists for people with chronic kidney disease requiring dialysis

BACKGROUND

People with chronic kidney disease (CKD) requiring dialysis are at a particularly high risk of cardiovascular death and morbidity. Several clinical studies suggested that aldosterone antagonists would be a promising treatment option for people undergoing dialysis. However, the clinical efficacy and potential harm of aldosterone antagonists for people with CKD on dialysis has yet to be determined.

OBJECTIVES

This review aimed to evaluate the benefits and harms of aldosterone antagonists, both non-selective (spironolactone) and selective (eplerenone), in comparison to control (placebo or standard care) in people with CKD requiring haemodialysis (HD) or peritoneal dialysis (PD).

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Register of Studies up to 5 August 2020 using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov.

SELECTION CRITERIA

We included parallel randomised controlled trials (RCTs), cross-over RCTs, and quasi-RCTs (where group allocation is by a method that is not truly random, such as alternation, assignment based on alternate medical records, date of birth, case record number, or other predictable methods) that compared aldosterone antagonists with placebo or standard care in people with CKD requiring dialysis.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed risk of bias for included studies. We used a random-effects model meta-analysis to perform a quantitative synthesis of the data. We used the I² statistic to measure heterogeneity among the studies in each analysis. We indicated summary estimates as a risk ratio (RR) for dichotomous outcomes, mean difference (MD) for continuous outcomes, or standardised mean differences (SMD) if different scales were used, with their 95% confidence interval (CI). We assessed the certainty of the evidence for each of the main outcomes using the GRADE (Grades of Recommendation, Assessment, Development, and Evaluation) approach.

MAIN RESULTS

We included 16 studies (14 parallel RCTs and two cross-over RCTs) involving a total of 1446 participants. Thirteen studies compared spironolactone to placebo or standard care and one study compared eplerenone to a placebo. Most included studies had an unclear or high risk of bias. Compared to control, aldosterone antagonists probably reduced the risk of death (any cause) for people with CKD requiring dialysis (9 studies, 1119 participants: RR 0.45, 95% CI 0.30 to 0.67; I² = 0%; moderate certainty of evidence). Aldosterone antagonist probably decreased the risk of death due to cardiovascular disease (6 studies, 908 participants: RR 0.37, 95% CI 0.22 to 0.64; I² = 0%; moderate certainty of evidence) and cardiovascular and cerebrovascular morbidity (3 studies, 328 participants: RR 0.38, 95% CI 0.18 to 0.76; I² = 0%; moderate certainty of evidence). While aldosterone antagonists probably increased risk of gynaecomastia compared with control (4 studies, 768 participants: RR 5.95, 95% CI 1.93 to 18.3; I² = 0%; moderate certainty of evidence), aldosterone antagonists may make little or no difference to the risk of hyperkalaemia (9 studies, 981 participants: RR 1.41, 95% CI 0.72 to 2.78; I² = 47%; low certainty of evidence). Aldosterone antagonists had a marginal effect on left ventricular mass among participants undergoing dialysis (8 studies, 633 participants: SMD -0.42, 95% CI -0.78 to 0.05; I² = 77%). In people with CKD requiring dialysis received aldosterone antagonists compared to control, there were 72 fewer deaths from all causes per 1000 participants (95% CI 47 to 98) with a number needed to treat for an additional beneficial outcome (NNTB) of 14 (95% CI 10 to 21) and for gynaecomastia were 26 events per 1000 participants (95% CI 15 to 39) with a number need to treat for an additional harmful outcome (NNTH) of 38 (95% CI 26 to 68).

AUTHORS' CONCLUSIONS

Based on moderate certainty of the evidence, aldosterone antagonists probably reduces the risk of all-cause and cardiovascular death and probably reduces morbidity due to cardiovascular and cerebrovascular disease in people with CKD requiring dialysis. For the adverse effect of gynaecomastia, the risk was increased compared to control. For this outcome, the absolute risk was lower than the absolute risk of death. It is hoped the three large ongoing studies will provide better certainty of evidence.

Mitigating risk of aldosterone in diabetic kidney disease

PURPOSE OF REVIEW

Diabetic kidney disease is a growing problem leading to end-stage kidney disease but also atherosclerotic cardiovascular disease and heart failure. Aldosterone is a key risk factor promoting inflammation and fibrosis causing cardio-renal failure. Current options and challenges with mitigating the risk of aldosterone are reviewed.

RECENT FINDINGS

More aggressive renin-angiotensin-aldosterone system (RAAS) blockade can be maintained in individuals with hyperkalemia if new potassium binders are added. Aldosterone synthase inhibitors may lower aldosterone without causing hyperkalemia. Novel nonsteroidal mineralocorticoid receptor antagonists (MRA) are able to lower proteinuria and markers of heart failure, with limited potassium problems and without renal impairment. Ongoing clinical trials are evaluating the safety and potential benefits of nonsteroidal MRAs on progression of renal disease and development of cardiovascular outcomes in type 2 diabetes and kidney disease.

SUMMARY

Aldosterone is an important driver of inflammation and fibrosis leading to renal and cardiovascular complications. MRA lower albuminuria but data showing prevention of end-stage kidney disease are lacking. Side effects including hyperkalemia have previously prevented long-term studies in diabetic kidney disease but new treatment strategies with potassium binders, aldosterone synthase inhibitors and nonsteroidal MRA have been developed for clinical testing.

Effect of Mineralocorticoid Receptor Blockade on Arterial Stiffness and Endothelial Function: A Meta-Analysis of Randomized Trials

Although numerous studies have confirmed the beneficial effects of pharmacological therapy for arterial stiffness and endothelial dysfunction, which are predictors/therapeutic targets for cardiovascular diseases, only a few overall quantitative evaluations of MRAs (mineralocorticoid receptor antagonists) exist. We searched PubMed and Cochrane CENTRAL (Cochrane Central Register of Controlled Trials) for randomized trials evaluating MRA effects on arterial stiffness measured by pulse wave velocity (PWV) or augmentation index and endothelial function measured by flow-mediated dilation. Data from the included trials were pooled by using random-effects meta-analysis of the weighted mean difference (MD) between the comparator groups. The primary outcome was the MD of PWV. In 11 trials including 515 patients, the MRA treatment reduced the PWV when compared with control (MD, -0.75 m/s [95% CI, -1.12 to -0.39], P<0.00001), without heterogeneity. There were comparable effects of MRA on carotid-femoral PWV and those on other forms of PWV (P=0.705 for heterogeneity). The effects of MRA on PWV were independent of blood pressure reduction related to the treatment according to meta-regression analysis. The MRA treatment reduced the augmentation index compared with control in 5 trials including 283 patients (MD, -6.74% [95% CI, -10.26 to -3.21], P=0.0002) and increased the flow-mediated dilation in 11 trials including 570 patients (MD, 1.18% [95% CI, 0.14 to 2.23], P=0.03). In conclusion, the current meta-analysis demonstrates the beneficial effects of MRA on PWV, augmentation index, and flow-mediated dilation.

Mineralocorticoid Receptor Antagonist Use in Heart Failure With Reduced Ejection Fraction and End-Stage Renal Disease Patients on Dialysis: A Literature Review

Mineralocorticoid receptor antagonists (MRAs) are known to have a proven mortality benefit in heart failure with reduced ejection fraction (HFrEF) without kidney disease. As patients with end-stage renal disease (ESRD) requiring either peritoneal dialysis or hemodialysis were excluded in clinical trials of HFrEF, the data are scant on the appropriate use of MRAs in this population. The unknown efficacy, along with concerns of adverse effects such as hyperkalemia, has limited the willingness of clinicians to consider using MRAs in these patients. However, it is unclear whether the risk of hyperkalemia is present if a patient is oliguric or anuric. Current guidelines recommend against the use of MRAs in patients with chronic kidney disease, but do not address the use of MRAs in patients requiring dialysis. This article will review the epidemiology of heart failure in ESRD, the pathophysiological derangements of the renin-angiotensin-aldosterone system in patients with kidney disease, and the results from case series and trials of the use of MRAs in ESRD with HFrEF. Although limited to several small trials using MRAs in peritoneal and hemodialysis patients with or without HFrEF, the current literature appears to show the potential for clinical benefits with little risk.

Effects of spironolactone on extrasystoles and heart rate variability in haemodialysis patients: a randomised crossover trial

BACKGROUND

Spironolactone treatment reduces mortality in haemodialysis (HD) patients. The objective of this study was to evaluate if spironolactone affects cardiac electric activity in this population.

METHODS

Participants were randomised to start with spironolactone 50 mg daily or observation (12 weeks) with subsequent washout (6 weeks) and crossover to the other intervention (12 weeks). Long-term electrocardiograms were recorded and assessed with blinding to treatment. The primary outcome was premature ventricular complexes (PVC), and secondary outcomes were atrial premature contractions (APC) and heart rate variability (HRV).

RESULTS

Thirty participants were recruited, and data for 16 participants were included in the analysis. Treatment was associated with an increase in PVCs by 9.7 [95% confidence interval (CI): 1.5 to 18] h^-1. HRV time-domain variables increased during treatment, the standard deviation of all beat-to-beat intervals by 18 (95% CI: 3.3 to 32) milliseconds (ms) and the standard deviation of the averages of beat-to-beat intervals in all 5-min segments of the entire recording by 16 (95% CI: 1.5 to 30) ms. There were no significant differences in other variables.

CONCLUSION

Spironolactone treatment increases PVCs in HD, indicating a possible proarrhythmic effect. However, improved cardiac autonomic function, as indicated by an increased HRV, may contribute to the survival benefit from spironolactone treatment in HD patients.

Antihypertensive Therapy in Patients Receiving Maintenance Hemodialysis: A Narrative Review of the Available Clinical-Trial Evidence

BACKGROUND

Blood pressure (BP)-lowering with the use of antihypertensive drugs appears to protect the cardiovascular (CV) system in hemodialysis patients. However, the optimal treatment algorithm of hypertension remains elusive; extrapolation of clinical-trial evidence from the general population may not be optimal.

METHODS

For this narrative review, we searched the Medline/PubMed database (inception to August 01, 2019) to identify randomized clinical trials evaluating the efficacy of antihypertensive drugs on CV outcomes and mortality in patients on hemodialysis.

RESULTS

Randomized trials with angiotensin-converting-enzyme-inhibitors (ACEIs) or angiotensinreceptor- blockers (ARBs) failed to provide consistent cardioprotection. β-blockers may provide a more consistent CV benefit. Although some early clinical trials have shown that mineralocorticoid-receptorantagonists (MRAs) reduce CV mortality, the associated risk of hyperkalemia raises important safety concerns on the use of MRAs as add-on therapy.

CONCLUSION

Our first-line therapy of hypertension in hemodialysis is the assessment and management of dry-weight and optimization of dialysis prescription. Based on the available clinical-trial evidence, we prescribe atenolol 3 times/week after dialysis as the first-line pharmacological option of hypertension to our patients without specific indications for other agents. Long-acting dihydropyridines and ACEIs/ARBs are our second-line and third-line choices, respectively. We avoid using MRAs and await results from ongoing trials testing their safety and efficacy. In patients receiving maintenance hemodialysis, randomized trials are clearly warranted in order to define BP targets and the comparative effectiveness of different antihypertensive drugs.

Effect of spironolactone on cardiovascular morbidity and mortality in patients with hypertension and glucose metabolism disorders (ESCAM): a study protocol for a pragmatic randomised controlled trial

INTRODUCTION

Hypertension combined with diabetes and hypokalemia is more likely to develop hyperaldosteronism and is at higher risk of cardiovascular events. There is evidence that activation of aldosterone and mineralocorticoid receptors may play a significant role in the occurrence of cardiovascular events in patients with hypertension and diabetes. Clinical studies have demonstrated that spironolactone can reduce the incidence of cardiovascular events in patients with chronic kidney diseases or severe heart failure. However, the effect of spironolactone on cardiovascular risk in patients with hypertension and glucose metabolism disorders (GMD) and low potassium has been scarcely studied. Therefore, this study aims to evaluate whether add-on spironolactone (conventional antihypertensive drugs alone vs conventional antihypertensive drugs+spironolactone) can reduce the morbidity and mortality of cardiovascular events in this population.

METHODS AND ANALYSIS

In this multicentre, randomised, parallel-controlled study, a total of 7140 hypertensive patients aged 45-75 years with GMD and low potassium will be randomised in a 1:1 manner to the control or the spironolactone group (20 mg/day or with a maximum dose of 40 mg). The primary objective is to estimate the difference in the HR of composite cardiovascular events between the two groups. We will also assess the effects of spironolactone on individual cardiovascular events and the progression of diabetes and renal dysfunction.

ETHICS AND DISSEMINATION

This protocol was approved by the Independent Ethics Committee of People's Hospital of Xinjiang Uygur Autonomous Region (no. 2020020618). The results will be disseminated in peer-reviewed journals and at scientific conferences.

TRIAL REGISTRATION NUMBER

ChiCTR2000028909.

Role of the vascular endothelial sodium channel activation in the genesis of pathologically increased cardiovascular stiffness

Cardiovascular (CV) stiffening represents a complex series of events evolving from pathological changes in individual cells of the vasculature and heart which leads to overt tissue fibrosis. While vascular stiffening occurs naturally with ageing it is accelerated in states of insulin (INS) resistance, such as obesity and type 2 diabetes. CV stiffening is clinically manifested as increased arterial pulse wave velocity and myocardial fibrosis-induced diastolic dysfunction. A key question that remains is how are these events mechanistically linked. In this regard, heightened activation of vascular mineralocorticoid receptors (MR) and hyperinsulinaemia occur in obesity and INS resistance states. Further, a downstream mediator of MR and INS receptor activation, the endothelial cell Na+ channel (EnNaC), has recently been identified as a key molecular determinant of endothelial dysfunction and CV fibrosis and stiffening. Increased activity of the EnNaC results in a number of negative consequences including stiffening of the cortical actin cytoskeleton in endothelial cells, impaired endothelial NO release, increased oxidative stress-meditated NO destruction, increased vascular permeability, and stimulation of an inflammatory environment. Such endothelial alterations impact vascular function and stiffening through regulation of vascular tone and stimulation of tissue remodelling including fibrosis. In the case of the heart, obesity and INS resistance are associated with coronary vascular endothelial stiffening and associated reductions in bioavailable NO leading to heart failure with preserved systolic function (HFpEF). After a brief discussion on mechanisms leading to vascular stiffness per se, this review then focuses on recent findings regarding the role of INS and aldosterone to enhance EnNaC activity and associated CV stiffness in obesity/INS resistance states. Finally, we discuss how coronary artery-mediated EnNaC activation may lead to cardiac fibrosis and HFpEF, a condition that is especially pronounced in obese and diabetic females.

Hyperkalemia and Acute Kidney Injury with Spironolactone Use Among Patients with Heart Failure

OBJECTIVE

To quantify the risk of hyperkalemia and acute kidney injury (AKI) when spironolactone use is added on to loop diuretic use among patients with heart failure, and to evaluate whether the risk is modified by level of kidney function.

METHODS

We identified 17,110 patients with heart failure treated with loop diuretics between January 1, 2004, and December 31, 2016 within the Geisinger Health System. We estimated the incidence of hyperkalemia and AKI associated with spironolactone initiation, and used target trial emulation methods to minimize confounding by indication.

RESULTS

During a mean follow-up of 134 mo, 3229 of 17,110 patients (18.9%) initiated spironolactone. Incidence rates of hyperkalemia and AKI in patients using spironolactone with a loop diuretic were 2.9 and 10.1 events per 1000 person-months, respectively. In propensity score-matched analyses, spironolactone initiation was associated with higher hyperkalemia and AKI risk compared with loop alone (hazard ratio, 1.69; 95% CI, 1.35 to 2.10; P<.001, and hazard ratio, 1.12; 95% CI, 1.00 to 1.26; P=.04, respectively). There were no differences in the relative risk of either outcome associated with spironolactone by level of kidney function.

CONCLUSION

The addition of spironolactone to loop diuretics in patients with heart failure was associated with higher risk of hyperkalemia and AKI; these risks must be weighed against the potential benefits of spironolactone.

Mineralocorticoid receptor antagonists in patients with chronic kidney disease

Mineralocorticoid receptor antagonists (MRA) can reduce cardiovascular morbidity and mortality in patients with heart failure and ischemic heart disease. In addition, these agents have been used in patients with diabetic nephropathy to control proteinuria and slow down chronic kidney disease (CKD) progression. Current guidelines recommend against the use of MRAs in patients with advanced CKD. However, there is growing interest on their use in this population that has unmet needs (high cardiovascular morbidity and mortality) and unique challenges (risk of acute kidney injury or hyperkalemia). This narrative review discusses the emerging role of MRAs for the management of cardiovascular disease and/or the prevention of CKD progression, highlighting results from randomized controlled trials and presenting real-world data from available registries. Results from recent trials in patients on maintenance dialysis are also discussed.

Heart failure management in dialysis patients: Many treatment options with no clear evidence

Heart failure with reduced ejection fraction (HFrEF) impacts approximately 20% of dialysis patients and is associated with high mortality rates. Key issues discussed in this review of HFrEF management in dialysis include dialysis modality choice, vascular access, dialysate composition, pharmacological therapies, and strategies to reduce sudden cardiac death, including the use of cardiac devices. Peritoneal dialysis and more frequent or longer duration of hemodialysis may be better tolerated due to slower ultrafiltration rates, leading to less intradialytic hypotension and better volume control; dialysate cooling and higher dialysate calcium may also have benefits. While high-quality evidence exists for many drug classes in the non-dialysis population, dialysis patients were excluded from major trials, and only limited data exist for many medications in kidney failure patients. Despite limited evidence, beta blocker and angiotensin-converting enzyme inhibitor or angiotensin receptor blocker use is common in dialysis. Similarly, devices such as implantable cardiac defibrillators (ICDs) and cardiac resynchronization therapy that have proven benefits in non-dialysis HFrEF patients have not consistently been beneficial in the limited dialysis studies. The use of leadless pacemakers and subcutaneous ICDs can mitigate future hemodialysis access limitations. Additional research is critical to address knowledge gaps in treating maintenance dialysis patients with HFrEF.

Blood pressure and volume management in dialysis: conclusions from a Kidney Disease: Improving Global Outcomes (KDIGO) Controversies Conference

Blood pressure (BP) and volume control are critical components of dialysis care and have substantial impacts on patient symptoms, quality of life, and cardiovascular complications. Yet, developing consensus best practices for BP and volume control have been challenging, given the absence of objective measures of extracellular volume status and the lack of high-quality evidence for many therapeutic interventions. In February of 2019, Kidney Disease: Improving Global Outcomes (KDIGO) held a Controversies Conference titled Blood Pressure and Volume Management in Dialysis to assess the current state of knowledge related to BP and volume management and identify opportunities to improve clinical and patient-reported outcomes among individuals receiving maintenance dialysis. Four major topics were addressed: BP measurement, BP targets, and pharmacologic management of suboptimal BP; dialysis prescriptions as they relate to BP and volume; extracellular volume assessment and management with a focus on technology-based solutions; and volume-related patient symptoms and experiences. The overarching theme resulting from presentations and discussions was that managing BP and volume in dialysis involves weighing multiple clinical factors and risk considerations as well as patient lifestyle and preferences, all within a narrow therapeutic window for avoiding acute or chronic volume-related complications. Striking this challenging balance requires individualizing the dialysis prescription by incorporating comorbid health conditions, treatment hemodynamic patterns, clinical judgment, and patient preferences into decision-making, all within local resource constraints.

Uncertainties in BP management in dialysis patients

Hypertension in dialysis patients is extremely common. In this article, we review the current evidence for blood pressure (BP) goals in hemodialysis patients, and consider the effectiveness of interventions by which BP may be lowered, including manipulation of dietary and dialysate sodium; optimization of extracellular water; prolongation of dialysis time; and antihypertensive medication. Although two meta-analyses suggest lowering BP using antihypertensive drugs might be beneficial in reducing cardiovascular events and mortality, there are insufficient rigorously designed trials in hypertensive hemodialysis populations to determine preferred antihypertensive drug classes. We suggest aiming for predialysis systolic BP between 130 and 159 mm Hg, while at the same time acknowledge the significant limitations of the data upon which it is based. We conclude by summarizing current knowledge as regards management of hypertension in the peritoneal dialysis population and make recommendations for future research in this field.

Blood pressure targets and pharmacotherapy for hypertensive patients on hemodialysis

INTRODUCTION

Hypertension is highly prevalent in patients with end-stage kidney disease on hemodialysis and is often not well controlled. Blood pressure (BP) levels before and after hemodialysis have a U-shaped relationship with cardiovascular and all-cause mortality. Although antihypertensive drugs are recommended for patients in whom BP cannot be controlled appropriately by non-pharmacological interventions, large-scale randomized controlled clinical trials are lacking.

AREAS COVERED

The authors review the pharmacotherapy used in hypertensive patients on dialysis, primarily focusing on reports published since 2000. An electronic search of MEDLINE was conducted using relevant key search terms, including 'hypertension', 'pharmacotherapy', 'dialysis', 'kidney disease', and 'antihypertensive drug'. Systematic and narrative reviews and original investigations were retrieved in our research.

EXPERT OPINION

When a drug is administered to patients on dialysis, the comorbidities and characteristics of each drug, including its dialyzability, should be considered. Pharmacological lowering of BP in hypertensive patients on hemodialysis is associated with improvements in mortality. β-blockers should be considered first-line agents and calcium channel blockers as second-line therapy. Renin-angiotensin-aldosterone system inhibitors have not shown superiority to other antihypertensive drugs for patients on hemodialysis.

Prevalence and Management of Hypokalemia in Peritoneal Dialysis Patients in Qatar

Introduction

Hypokalemia is common in patients undergoing peritoneal dialysis (PD). It is associated with increased cardiovascular and all-cause mortality. Treatment usually includes oral potassium supplements, which are poorly tolerated. Our aim was to evaluate the prevalence of hypokalemia in PD patients in Qatar and to improve treatment measures.

Methods

All PD patients in Qatar with persistent hypokalemia and on potassium supplement were included. We performed a root cause analysis, and a management pathway was created. We collected data before (Period 1) and after (Period 2) implementation of the new pathway.

Results

A total of 143 patients with a mean age of 54 years (range 21–82 years) were included in the study. Initial results of Period 1 showed hypokalemia in 48 patients (34%); of these, 14 (29%) had hypomagnesemia. Hypokalemia resolved in 10 of the patients after correction of their hypomagnesemia. The remaining 4 patients continued to require potassium supplementation despite correction of their hypomagnesemia. We started spironolactone (25 mg daily) in 13 of the hypokalemia patients. After 3 months, their mean serum potassium level improved from 3.2 ± 0.3 mmol/L to 3.9 ± 0.4 mmol/L (p < 0.001), and the prevalence of patients with persistent hypokalemia decreased from 36% to 21% (statistically significant with p= 0.006). No episodes of hypotension or hyperkalemia were observed. Only 1 patient developed mild gynecomastia without discontinuation of the medications.

Conclusion

Our study showed that hypokalemia is a prevalent problem in PD patients in Qatar. Hypomagnesemia is a significant contributing factor to hypokalemia in PD and correcting it leads to improvement of hypokalemia. Addition of spironolactone is safe and effective in treating hypokalemia. Implementing a holistic pathway led to a significant improvement in hypokalemia prevalence in PD patients.

Spironolactone ameliorates endothelial dysfunction through inhibition of the AGE/RAGE axis in a chronic renal failure rat model

BACKGROUND

Spironolactone can improve endothelial dysfunction in the setting of heart failure and diabetes models. However, its beneficial effect in the cardiovascular system is not clear in the setting of non-diabetic renal failure. We conducted this study to investigate whether spironolactone can ameliorate endothelial dysfunction in a 5/6 nephrectomy model, and to determine the underlying mechanism.

METHODS

Twenty-four Sprague-Dawley rats were divided into four groups. A renal failure model was created using the 5/6 nephrectomy method. The four groups included: Sham-operation group (Group1), chronic kidney disease (CKD; Group2), CKD + ALT-711 (advanced glycation end products [AGEs] breaker; Group 3), and CKD + spironolactone group (Group4). Acetylcholine (Ach)-mediated vasodilatation responses were compared between the four groups. To investigate the underlying mechanism, we cultured human aortic endothelial cells (HAECs) for in-vitro assays. Differences between two groups were determined with the paired student's t test. Differences between three or more groups were determined through one-way analysis of variance (ANOVA) with post-hoc analysis with LSD method.

RESULTS

Compared with Group 1, Group 2 has a significantly impaired Ach-mediated vasodilatation response. Group 3 and 4 exhibited improved vasoreactivity responses. To determine the underlying mechanism, we performed an in-vitro study using cultured HAECs. We noted significant sirtuin-3 (SIRT3) protein downregulation, reduced phosphorylation of endothelial nitric oxide synthase at serine 1177 (p-eNOS), and increased intracellular oxidative stress in cultured HAECs treated with AGEs (200 μg/mL). These effects were counter-regulated when cultured HAECs were pretreated with spironolactone (10 μM). Furthermore, the increased p-eNOS production by spironolactone was abrogated when the HAECs were pretreated with tenolvin (1 μM), a SIRT3 inhibitor.

CONCLUSIONS

Spironolactone could ameliorate endothelial dysfunction in a 5/6 nephrectomy renal failure model through AGEs/Receptor for AGEs (RAGEs) axis inhibition, SIRT3 upregulation, and nicotinamide adenine dinucleotide phosphate oxidase-2 (NOX-2) and its associated intracellular oxidative stress attenuation.

Effect of spironolactone on the progression of coronary calcification in peritoneal dialysis patients: a pilot study

INTRODUCTION

There is evidence that aldosterone plays a role in the pathogenesis of vascular calcification. The aim of this study was to evaluate the effect of spironolactone, a mineralocorticoid receptor antagonist, on the progression of coronary calcification (CC) in peritoneal dialysis patients and to identify the factors involved in this progression.

METHODS

Thirty-three patients with a coronary calcium score (CCS) ≥ 30, detected through multi-detector computed tomography (MDCT) and expressed in Agatston units, were randomly assigned to a group receiving 25mg spironolactone per day for 12 months (spironolactone group) and a control group not receiving this drug. The primary outcome was a percentage change in CCS from baseline to end of the study (relative progression), when a further MDCT was conducted. Patients who had progression of CC were compared with those who did not progress.

RESULTS

Sixteen patients, seven in the spironolactone group and nine in the control group, concluded the study. The relative progression of the CCS was similar in both groups, 17.2% and 27.5% in the spironolactone and control groups respectively. Fifty-seven percent of the treated patients and 67% of those in the control group presented progression in the CC scores (p = 0.697). Progressor patients differed from non-progressors because they presented higher levels of calcium and low-density lipoprotein cholesterol and lower levels of albumin.

CONCLUSION

In peritoneal dialysis patients, spironolactone did not attenuate the progression of CC. However, large-scale studies are needed to confirm this observation. Disorders of mineral metabolism and dyslipidemia are involved in the progression of CC.

Effect of spironolactone for 1 yr on endothelial function and vascular inflammation biomarkers in renal transplant recipients

Kidney transplantation is associated with increased cardiovascular risk. Endothelial dysfunction and vascular inflammation contribute to negative outcome. In experimental models, mineralocorticoid receptor antagonists improved endothelial function and reduced inflammation. The present study tested the hypothesis that the mineralocorticoid receptor antagonist spironolactone improves endothelial function and reduces vascular inflammation in renal transplant patients. Eighty prevalent renal transplant patients from an ongoing, double-blind randomized placebo-controlled trial were included. Paired plasma samples before and after 1 yr of treatment (n = 39 in the spironolactone-treated group and 41 in the placebo-treated group) were used to determine markers of endothelial dysfunction (nitrite, nitrate, cGMP, arginine, citrulline, ornithine, asymmetric dimethylarginine, symmetric dimethylarginine, N^G-monomethyl-l-arginine, von Willebrand factor, tissue-type plasminogen activator antigen, and plasminogen activator inhibitor 1 antigen) and markers of inflammation (intercellular adhesion molecule, vascular adhesion molecule, high-sensitivity C-reactive protein, and serum amyloid protein A). The median time since the transplantation was 4.6 (0.12-22.3) yr in the spironolactone-treated group and 2.1 (0.17-13.9) yr in the placebo-treated group (P > 0.05). Spironolactone increased plasma aldosterone (P < 0.001) and K⁺ (P < 0.001). Blood pressure did not change significantly. No significant differences were detected between groups in any of the measured markers of endothelial dysfunction or inflammation except in the subgroup analysis of patients with diabetes, where spironolactone decreased nitrite compared with placebo. In this study, mineralocorticoid receptor antagonism did not improve biomarkers of endothelial dysfunction or vascular inflammation in prevalent renal transplant patients. Further studies are needed to evaluate the potential beneficial effect of early or late mineralocorticoid receptor antagonism on vascular outcomes in renal transplant patients.

Safety evaluation and cardiovascular effect of additional use of spironolactone in hemodialysis patients: a meta-analysis

Objective: To evaluate the safety and cardiovascular effect of low-dose spironolactone administration in end-stage renal failure patients undergoing hemodialysis coupled with conventional treatment.

Methods: We conducted a systematic search for clinical trials on the safety and cardiovascular effect of additional low-dose spironolactone in hemodialysis patients. The search was performed on PubMed, EMBASE, Cochrane Library, and CBM databases. Relevant references (up to February 2016) were retrieved and subsequent results analyzed with a random-effects model or a fixed-effects model.

Results: We identified nine trials with a total sample size of 765 patients. The results did not indicate significant differences regarding safety and serum potassium levels (mean difference [MD]=0.23, P=0.09) between the two treatment options. However, patients receiving low-dose spironolactone exhibited improvements in left venticular mass index (LVMI) (standardized mean difference= –0.58, P<0.00001) and left ventricular ejection fraction (LVEF) (MD=4.91, P<0.0001) with an additional decrease in systolic blood pressure (MD= –6.97, P=0.0001) and diastolic blood pressure (MD= –4.01, P=0.007). Furthermore, the clinical (OR=0.4, P=0.0003) or cardiovascular and cerebrovascular-related (OR=0.4, P=0.002) mortality was significantly lower among those patients.

Conclusion: These results indicated that additional use of low-dose spironolactone associated with conventional treatment does not have a significant impact on serum potassium levels in hemodialysis patients. What’s more, it might exert a protective effect on the cardiovascular system by optimizing LVMI, improving LVEF, decreasing arterial blood pressure and reducing events-related mortality. Further large sample size studies are needed to support these findings.

Aldosterone Antagonists Reduce the Risk of Cardiovascular Mortality in Dialysis Patients: A Meta-Analysis

Background and Purpose. Cardiovascular disease is the major cause of death in dialysis patients. Although aldosterone antagonists were considered a treatment for severe heart failure patients to reduce cardiac mortality, whether treating patients undergoing maintenance dialysis with aldosterone antagonists could reduce the risk of cardiocerebrovascular (CCV) remains unclear. We aim to systematically assess the efficacy and tolerability of the addition of aldosterone antagonists to conventional therapy in patients undergoing maintenance dialysis. Materials and Methods. We searched PubMed, EMBASE, the Cochrane Library, the Chinese Biomedical Literature Database (CBM), and the China National Knowledge Infrastructure (CNKI) for relevant articles. The primary endpoint of interest was CCV mortality. The secondary endpoints were all-cause mortality, left ventricular mass index (LVMI), and left ventricular ejection fraction (LVEF). Publication bias was evaluated using funnel plots and Egger's test. The meta-analysis was performed using Review Manager software version 5.3. Results. This analysis included 10 randomized controlled trials (RCTs) with 1172 total chronic dialysis patients. The use of aldosterone antagonists in the dialysis population resulted in a marked reduction in CCV mortality (RR 0.42, 95% CI 0.26-0.65, P=0.0002) and all-cause mortality (RR0.46, 95%CI 0.32-0.66, P<0.0001). The LVEF was improved by treatment with aldosterone antagonists (WMD 6.35%, P<0.00001). Moreover, aldosterone antagonists decreased the LVMI (WMD -8.69 g/m², P=0.0006), whereas aldosterone antagonists increased the occurrence of hyperkalemia (RR1.70, 95%CI 1-2.88, P=0.05) and gynecomastia (RR 8.01, 95% CI 2.44- 26.27, P=0.0006). Conclusions. Addition of aldosterone antagonists to conventional treatment in chronic dialysis patients may reduce CCV mortality, improve cardiac function, and simultaneously decrease LVMI.

Assessment and Management of Hypertension among Patients on Peritoneal Dialysis

Approximately 7%-10% of patients with ESKD worldwide undergo peritoneal dialysis (PD) as kidney replacement therapy. The continuous nature of this dialytic modality and the absence of acute shifts in pressure and volume parameters is an important differentiation between PD and in-center hemodialysis. However, the burden of hypertension and prognostic association of BP with mortality follow comparable patterns in both modalities. Although management of hypertension uses similar therapeutic principles, long-term preservation of residual diuresis and longevity of peritoneal membrane function require particular attention in the prescription of the appropriate dialysis regimen among those on PD. Dietary sodium restriction, appropriate use of icodextrin, and limited exposure of peritoneal membrane to bioincompatible solutions, as well as adaptation of the PD regimen to the peritoneal transport characteristics, are first-line therapeutic strategies to achieve adequate volume control with a potential long-term benefit on technique survival. Antihypertensive drug therapy is a second-line therapeutic approach, used when BP remains unresponsive to the above volume management strategies. In this article, we review the available evidence on epidemiology, diagnosis, and treatment of hypertension among patients on PD and discuss similarities and differences between PD and in-center hemodialysis. We conclude with a call for randomized trials aiming to elucidate several areas of uncertainty in management of hypertension in the PD population.

A randomized controlled trial of the effect of spironolactone on left ventricular mass in hemodialysis patients

Mineralocorticoid receptor antagonists have beneficial effects on left ventricular remodeling, cardiac fibrosis, and arrhythmia in heart failure, but efficacy and safety in dialysis patients is less clear. We evaluated the effect of spironolactone on left ventricular mass (LVM), an independent predictor of all-cause and cardiovascular mortality, in hemodialysis patients. In this placebo-controlled, parallel-group trial, 97 hemodialysis patients (23% female; mean age 60.3 years) were randomized to spironolactone 50 mg once daily (n=50) or placebo (n=47). The primary efficacy endpoint was change in LVM index (LVMi) from baseline to 40 weeks as determined by cardiac magnetic resonance imaging. Safety endpoints were development of hyperkalemia and change in residual renal function. There was no significant change in LVMi in participants randomized to spironolactone compared to placebo (-2.86±11.87 vs. 0.41±10.84 g/m²). There was also no difference in the secondary outcomes of mean 24-hour systolic or diastolic ambulatory blood pressure, left ventricular ejection fraction, 6-minute walk test distance, or New York Heart Association functional class. Moderate hyperkalemia (pre-dialysis potassium levels of 6.0-6.5 mmol/L) was more frequent with spironolactone treatment (155 vs. 80 events), but severe hyperkalemia (≥6.5 mmol/L) was not (14 vs. 24 events). Changes in residual urine volume and measured glomerular filtration rate did not differ between groups. There were no deaths in the spironolactone group and 4 deaths in the placebo group. Thus, treatment with 50 mg spironolactone did not change left ventricular mass index, cardiac function, or blood pressure in hemodialysis patients. Spironolactone increased the frequency of moderate hyperkalemia, but did not increase severe hyperkalemia.

Antihypertensive Agents in the Dialysis Patient

PURPOSE OF REVIEW

Hypertension and antihypertensive drug utilization are remarkably prevalent in ESRD patients. Management of blood pressure elevation in this population is complicated by many factors, including a multidimensional etiology, challenges in obtaining accurate and appropriately timed blood pressure measurements, highly specific drug dosing requirements, and a paucity of outcomes-based evidence to guide management decisions. The purpose of this review is to summarize and apply knowledge from existing clinical trials to enhance safe and effective use of antihypertensive agents in dialysis patients.

RECENT FINDINGS

Two meta-analyses have established the benefit of antihypertensive therapy in ESRD. Data supporting the use of one antihypertensive class over another is less robust; however, beta-blockers have more clearly demonstrated improved cardiovascular outcomes in prospective randomized trials. Interdialytic home blood pressure monitoring has been demonstrated to be better associated with cardiovascular outcomes than clinic pre- or post-dialysis readings and should ideally be considered as a routine part of blood pressure management in this population. As data from small trials provides limited guidance for the management of hypertension in ESRD, more research is needed to guide medication selection and utilization. Specifically, large prospective randomized trails comparing cardiovascular outcomes of various medication classes and differing blood pressure targets are needed.

Pathophysiological mechanisms of mineralocorticoid receptor-dependent cardiovascular and chronic kidney disease

Accumulating evidence has indicated the potential contributions of aldosterone and mineralocorticoid receptor (MR) to the pathophysiology of cardiovascular disease (CVD) and chronic kidney disease (CKD). Patients with primary aldosteronism have a higher risk of CVD and CKD than those with essential hypertension. MR is strongly expressed in endothelial cells, vascular smooth muscle cells, cardiomyocytes, fibroblasts, macrophages, glomerular mesangial cells, podocytes, and proximal tubular cells. In these cardiovascular and renal cells, aldosterone-induced cell injury is prevented by MR blockade. Interestingly, MR antagonists elicit beneficial effects on CVD and CKD in subjects with low or normal plasma aldosterone levels. Recent studies have shown that during development of CVD and CKD, cardiovascular and renal MR is activated by glucocorticoid and ligand-independent mechanisms, such as Rac1 signaling pathways. These data indicate that inappropriate activation of local MR contributes to cardiovascular and renal tissue injury through aldosterone-dependent and -independent mechanisms. In this review, recent findings on the specific role of cardiovascular and renal MR in the pathogenesis of CVD and CKD are summarized.

Safety and cardiovascular efficacy of spironolactone in dialysis-dependent ESRD (SPin-D): a randomized, placebo-controlled, multiple dosage trial

The safety and efficacy of spironolactone is uncertain in end-stage renal disease. We randomized 129 maintenance hemodialysis patients to placebo (n=51) or spironolactone 12.5 mg (n=27), 25 mg (n=26), or 50 mg (n=25) daily for 36 weeks in a double-blind, placebo-controlled, multiple dosage trial to assess safety, tolerability and feasibility and to explore cardiovascular efficacy. The primary safety endpoints were hyperkalemia (potassium > 6.5 mEq/L) and hypotension requiring emergency department visit or hospitalization. Diastolic function was assessed by Doppler echocardiography. 125 participants (97%) completed dose escalation, with no significant difference in permanent study drug discontinuation between the groups (27.5% in placebo versus 16.7% in the combined spironolactone groups and 28% in the 50 mg group). Hyperkalemia frequency was similar between spironolactone and placebo (0.49 versus 0.50 events per patient-year) but demonstrated a significant linear trend due primarily to an increased event rate at the 50 mg dose (0.89 events per patient-year). The primary hypotension outcome was infrequent and similar with spironolactone and placebo (0.11 versus 0 events per patient-year). Gynecomastia was rare and did not differ significantly between groups. Change in diastolic function was similar with spironolactone and placebo. Spironolactone appears safe in carefully monitored maintenance hemodialysis patients, but did not affect cardiovascular parameters in this small study. Hyperkalemia occurs more frequently as dosage increases to 50 mg daily.