Long-term effects of spironolactone in peritoneal dialysis patients

Management of patients with heart failure and chronic kidney disease

Chronic kidney disease (CKD) and heart failure are often co-existing conditions due to a shared pathophysiological process involving neurohormonal activation and hemodynamic maladaptation. A wide range of pharmaceutical and interventional tools are available to patients with CKD, consisting of traditional ones with decades of experience and newer emerging therapies that are rapidly reshaping the landscape of medical care for this population. Management of patients with heart failure and CKD requires a stepwise approach based on renal function and the clinical phenotype of heart failure. This is often challenging due to altered drug pharmacokinetics interactions with various degrees of kidney function and frequent adverse effects from the therapy that lead to poor patient tolerance. Despite a great body of clinical evidence and guidelines that have offered various treatment options for patients with heart failure and CKD, respectively, patients with CKD are still underrepresented in heart failure clinical trials, especially for those with advanced CKD and end-stage renal disease (ESRD). Future studies are needed to better understand the generalizability of these therapeutic options among heart failures with different stages of CKD.

Clinical Properties and Non-Clinical Testing of Mineralocorticoid Receptor Antagonists in In Vitro Cell Models

Mineralocorticoid receptor antagonists (MRAs) are one of the renin-angiotensin-aldosterone system inhibitors widely used in clinical practice. While spironolactone and eplerenone have a long-standing profile in clinical medicine, finerenone is a novel agent within the MRA class. It has a higher specificity for mineralocorticoid receptors, eliciting less pronounced adverse effects. Although approved for clinical use in patients with chronic kidney disease and heart failure, intensive non-clinical research aims to further elucidate its mechanism of action, including dose-related selectivity. Within the field, animal models remain the gold standard for non-clinical testing of drug pharmacological and toxicological properties. Their role, however, has been challenged by recent advances in in vitro models, mainly through sophisticated analytical tools and developments in data analysis. Currently, in vitro models are gaining momentum as possible platforms for advanced pharmacological and pathophysiological studies. This article focuses on past, current, and possibly future in vitro cell models research with clinically relevant MRAs.

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.

Hypertensive Heart Disease: Mechanisms, Diagnosis and Treatment

Hypertensive heart disease (HHD) presents a substantial global health burden, spanning a spectrum from subtle cardiac functional alterations to overt heart failure. In this comprehensive review, we delved into the intricate pathophysiological mechanisms governing the onset and progression of HHD. We emphasized the significant role of neurohormonal activation, inflammation, and metabolic remodeling in HHD pathogenesis, offering insights into promising therapeutic avenues. Additionally, this review provided an overview of contemporary imaging diagnostic tools for precise HHD severity assessment. We discussed in detail the current potential treatments for HHD, including pharmacologic, lifestyle, and intervention devices. This review aimed to underscore the global importance of HHD and foster a deeper understanding of its pathophysiology, ultimately contributing to improved public health outcomes.

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.

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.

Drug-induced gynecomastia: A systematic review and meta-analysis of randomized clinical trials

OBJECTIVE

To review the evidence concerning treatment-related gynecomastia in patients taking spironolactone, antiandrogens, 5 alpha-reductase inhibitors, lipid-lowering and psychotropic drugs.

MATERIAL AND METHODS

A search of Medline and EMBASE was performed up to 30 June 2021. We included randomized controlled trials comparing the effects of a drug belonging to these classes versus placebo or versus a drug of the same class.

RESULTS

A total of 32 randomized controlled trials were included in the final review. There was an increased odds of gynecomastia in men receiving antiandrogens (OR = 17.38, 95% CI: 11.26 to 26.82; 6 trials, 9599 participants) and 5 alpha-reductase inhibitors compared to controls (OR = 1.77, 95% CI: 1.53 to 2.06; 7 series out of 6 trials, 34860 participants). The use of spironolactone in mixed gender populations was characterized by significantly higher odds of having gynecomastia compared to controls (OR = 8.39, 95% CI: 5.03 to 13.99; 14 trials, 3745 participants). No placebo-controlled trials focusing on the risk of gynecomastia in patients taking antipsychotic drugs was available, although there was a significant difference in the odds of having gynecomastia in a comparison between risperidone and quetiapine (OR = 4.32, 95% CI: 1.31 to 14.27; 3 trials, 343 participants). Limited evidence about the effects of statins on mammary glands was found.

CONCLUSIONS

Antiandrogens and to a lesser extent 5 alphareductase inhibitors and spironolactone are associated with an increased risk of developing gynecomastia. Such effect can be explained by a modification of the testosterone to estradiol ratio. Gynecomastia (and galactorrhea) associated to the use of conventional and certain atypical antipsychotics can be related to high prolactin levels.

Peritoneal Dialysis Guidelines 2019 Part 1 (Position paper of the Japanese Society for Dialysis Therapy)

Approximately 10 years have passed since the Peritoneal Dialysis Guidelines were formulated in 2009. Much evidence has been reported during the succeeding years, which were not taken into consideration in the previous guidelines, e.g., the next peritoneal dialysis PD trial of encapsulating peritoneal sclerosis (EPS) in Japan, the significance of angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs), the effects of icodextrin solution, new developments in peritoneal pathology, and a new international recommendation on a proposal for exit-site management. It is essential to incorporate these new developments into the new clinical practice guidelines. Meanwhile, the process of creating such guidelines has changed dramatically worldwide and differs from the process of creating what were “clinical practice guides.” For this revision, we not only conducted systematic reviews using global standard methods but also decided to adopt a two-part structure to create a reference tool, which could be used widely by the society’s members attending a variety of patients. Through a working group consensus, it was decided that Part 1 would present conventional descriptions and Part 2 would pose clinical questions (CQs) in a systematic review format. Thus, Part 1 vastly covers PD that would satisfy the requirements of the members of the Japanese Society for Dialysis Therapy (JSDT). This article is the duplicated publication from the Japanese version of the guidelines and has been reproduced with permission from the JSDT.

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.

Effects of diuretics on intradialytic hypotension in maintenance dialysis patients: a systematic review and meta-analysis

PURPOSE

Intradialytic hypotension (IDH) is a serious complication in dialysis patients. Diuretics might reduce the incidence of IDH by decreasing ultrafiltration. However, the effect of diuretics on IDH in maintenance dialysis patients is still unclear.

METHODS

We searched Medline, Embase, the Cochrane Library, China National Knowledge Infrastructure and clinical trials registries from 1945 to May 2019. Randomized controlled trials (RCTs) or observational studies about IDH in maintenance dialysis with diuretics were included.

RESULTS

Seven studies including 28,226 patients were included, of which 4 were RCTs involving mineralocorticoid receptor antagonists (MRAs) and 3 were observational studies involving loop diuretics. There was a trend that a lower incidence rate of IDH in maintenance dialysis patients who used loop diuretics than control, although the result was not statistically significant (OR 0.65, 95% CI 0.34-1.22, P = 0.18). Similarly, lower incidence rate of all-cause mortality (OR 0.92, 95% CI 0.87-0.99; P = 0.02) and cardiovascular (CV) mortality (OR 0.86, 95% CI 0.75-0.99, P = 0.03) in dialysis patients who used loop diuretics than control. On the contrary, there were no significant difference in the incidence of IDH (OR 1.35, 95% CI 0.78-2.34, P = 0.29) and all-cause mortality (OR 0.73, 95% CI 0.26-2.01; P = 0.54) and CV mortality (OR 0.57, 95% CI 0.14-2.25; P = 0.42) in maintenance dialysis patients who used MRAs compared with control.

CONCLUSION

Loop diuretics, but not MRAs, might have a potential benefit to reduce the incidence rate of IDH, all-cause mortality and CV mortality. More high-quality studies are needed to strengthen the arguments.

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.

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.

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.

Left-sided heart disease and risk of death in patients with end-stage kidney disease receiving haemodialysis: an observational study

BACKGROUND

Cardiovascular disease is the most common cause of death in patients with end-stage kidney disease on haemodialysis. The potential clinical consequence of systematic echocardiographic assessment is however not clear. In an unselected, contemporary population of patients on maintenance haemodialysis we aimed to assess: the prevalence of structural and functional heart disease, the potential therapeutic consequences of echocardiographic screening and whether left-sided heart disease is associated with prognosis.

METHODS

Adult chronic haemodialysis patients in two large dialysis centres had transthoracic echocardiography performed prior to dialysis and were followed prospectively. Significant left-sided heart disease was defined as moderate or severe left-sided valve disease or left ventricular ejection fraction (LVEF) ≤40%.

RESULTS

Among the 247 included patients (mean 66 years of age [95%CI 64-67], 68% male), 54 (22%) had significant left-sided heart disease. An LVEF ≤40% was observed in 31 patients (13%) and severe or moderate valve disease in 27 (11%) patients. The findings were not previously recognized in more than half of the patients (56%) prior to the study. Diagnosis had a potential impact on management in 31 (13%) patients including for 18 (7%) who would benefit from initiation of evidence-based heart failure therapy. After 2.8 years of follow-up, all-cause mortality among patients with and without left-sided heart disease was 52 and 32% respectively (hazard ratio [HR] 1.95 (95%CI 1.25-3.06). A multivariable adjusted Cox proportional hazard analysis showed that left-sided heart disease was an independent predictor of mortality with a HR of 1.60 (95%CI 1.01-2.55) along with age (HR per year 1.05 [95%CI 1.03-1.07]).

CONCLUSION

Left ventricular systolic dysfunction and moderate to severe valve disease are common and often unrecognized in patients with end-stage kidney failure on haemodialysis and are associated with a higher risk of death. For more than 10% of the included patients, systematic echocardiographic assessment had a potential clinical consequence.

Effect of Low-Sodium versus Conventional Sodium Dialysate on Left Ventricular Mass in Home and Self-Care Satellite Facility Hemodialysis Patients: A Randomized Clinical Trial

BACKGROUND

Fluid overload in patients undergoing hemodialysis contributes to cardiovascular morbidity and mortality. There is a global trend to lower dialysate sodium with the goal of reducing fluid overload.

METHODS

To investigate whether lower dialysate sodium during hemodialysis reduces left ventricular mass, we conducted a randomized trial in which patients received either low-sodium dialysate (135 mM) or conventional dialysate (140 mM) for 12 months. We included participants who were aged >18 years old, had a predialysis serum sodium ≥135 mM, and were receiving hemodialysis at home or a self-care satellite facility. Exclusion criteria included hemodialysis frequency >3.5 times per week and use of sodium profiling or hemodiafiltration. The main outcome was left ventricular mass index by cardiac magnetic resonance imaging.

RESULTS

The 99 participants had a median age of 51 years old; 67 were men, 31 had diabetes mellitus, and 59 had left ventricular hypertrophy. Over 12 months of follow-up, relative to control, a dialysate sodium concentration of 135 mmol/L did not change the left ventricular mass index, despite significant reductions at 6 and 12 months in interdialytic weight gain, in extracellular fluid volume, and in plasma B-type natriuretic peptide concentration (ratio of intervention to control). The intervention increased intradialytic hypotension (odds ratio [OR], 7.5; 95% confidence interval [95% CI], 1.1 to 49.8 at 6 months and OR, 3.6; 95% CI, 0.5 to 28.8 at 12 months). Five participants in the intervention arm could not complete the trial because of hypotension. We found no effect on health-related quality of life measures, perceived thirst or xerostomia, or dietary sodium intake.

CONCLUSIONS

Dialysate sodium of 135 mmol/L did not reduce left ventricular mass relative to control, despite improving fluid status.

CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER

The Australian New Zealand Clinical Trials Registry, ACTRN12611000975998.

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.

Current Management of Hyperkalemia in Patients on Dialysis

Patients with end-stage renal disease (ESRD) on maintenance dialysis have a high risk of developing hyperkalemia, generally defined as serum potassium (K⁺) concentrations of >5.0 mmol/l, particularly those undergoing maintenance hemodialysis. Currently, the key approaches to the management of hyperkalemia in patients with ESRD are dialysis, dietary K⁺ restriction, and avoidance of medications that increase hyperkalemia risk. In this review, we highlight the issues and challenges associated with effective management of hyperkalemia in patients undergoing maintenance dialysis using an illustrative case presentation. In addition, we examine the potential nondialysis options for the management of these patients, including use of the newer K⁺ binder agents patiromer and sodium zirconium cyclosilicate, which may reduce the need for the highly restrictive dialysis diet, with its own implication on nutritional status in patients with ESRD, as well as reducing the risk of potentially life-threatening hyperkalemia.

Prescribing high-quality peritoneal dialysis: The role of preserving residual kidney function

Maintenance of residual kidney function (RKF) is independently associated with increased survival in patients with end-stage renal disease. Presence of RKF is also associated with improved volume status, better nutritional status, reduced erythropoietin requirement, and decreased rate of peritonitis in patients on peritoneal dialysis (PD). Thus, the preservation of RKF is an important therapeutic end point in the management of patients on PD. Measurement of RKF in PD patients should be based on the mean of 24-h urinary creatinine and urea clearances, and ideally, this should be done quarterly. Compared to those started on hemodialysis, patients initiated on PD appear to have slower decline in RKF. The choice of PD modality should be based on patient preference, as there is no clear evidence to date showing one modality is superior than the other in preserving RKF. Peritoneal dialysates with neutral pH and low glucose degradation products seem to have a favorable effect on RKF. An angiotensin-converting enzyme inhibitor or angiotensin receptor blocker should be used whenever possible to preserve RKF and reduce cardiac mortality. Both loop diuretics and icodextrin can be utilized to maintain fluid balance in PD patients. However, caution should be taken to avoid volume depletion which could accelerate RKF decline. Short-term use of aminoglycosides does not have a detrimental impact on RKF, but prolonged use (>3 weeks) should be avoided to minimize the risk of ototoxicity. Lastly, potential nephrotoxic agents such as intravenous contrast should be used judiciously.

Effectiveness of Renin-Angiotensin-Aldosterone System Blockade on Residual Kidney Function and Peritoneal Membrane Function in Peritoneal Dialysis Patients: A Network Meta-Analysis

We performed a network meta-analysis of randomised controlled trials (RCTs) and non-randomised studies in adult peritoneal dialysis patients to evaluate the effects of specific renin-angiotensin aldosterone systems (RAAS) blockade classes on residual kidney function and peritoneal membrane function. Key outcome parameters included the following: residual glomerular filtration rate (rGFR), urine volume, anuria, dialysate-to-plasma creatinine ratio (D/P Cr), and acceptability of treatment. Indirect treatment effects were compared using random-effects model. Pooled standardised mean differences (SMDs) and odd ratios (ORs) were estimated with 95% confidence intervals (CIs). We identified 10 RCTs (n = 484) and 10 non-randomised studies (n = 3,305). Regarding changes in rGFR, RAAS blockade with angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin II receptor blockers (ARBs) were more efficacious than active control (SMD 0.55 [0.06–1.04] and 0.62 [0.19–1.04], respectively) with the protective effect on rGFR observed only after usage ≥12 months, and no differences among ACEIs and ARBs. Compared with active control, only ACEIs showed a significantly decreased risk of anuria (OR 0.62 [0.41–0.95]). No difference among treatments for urine volume and acceptability of treatment were observed, whereas evidence for D/P Cr is inconclusive. The small number of randomised studies and differences in outcome definitions used may limit the quality of the evidence.

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.

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.

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.

Clinical Studies of Interventions to Mitigate Cardiovascular Risk in Peritoneal Dialysis Patients

Cardiovascular disease (CVD) is highly prevalent in the peritoneal dialysis (PD) population, affecting up to 60% of cohorts. CVD is the primary cause of death in up to 40% of PD patients in Australia, New Zealand, and the United States. Cardiovascular mortality rates are reported to be approximately 14 per 100 patient-years, which are 10- to 20-fold greater than those of age- and sex-matched controls. The excess risk of CVD is related to a combination of traditional risk factors (such as hypertension, dyslipidemia, obesity, smoking, sedentary lifestyle, and insulin resistance), nontraditional (kidney disease-related) risk factors (such as anemia, chronic volume overload, inflammation, malnutrition, hyperuricemia, and mineral and bone disorder), and PD-specific risk factors (such as dialysis solutions, glycation end products, hypokalemia, residual kidney function, and ultrafiltration failure). Interventions targeting these factors may mitigate cardiovascular risk, although high-level clinical evidence is lacking. This review summarizes the evidence relating to cardiovascular interventions targeting modifiable CVD risk factors in PD patients, as well as highlighting the key recommendations of the International Society for Peritoneal Dialysis Cardiovascular and Metabolic Guidelines.

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.

Changes in serum and intracardiac fibroblast growth factor 23 during the progression of left ventricular hypertrophy in hypertensive model rats

BACKGROUND

Recent clinical studies have demonstrated that serum fibroblast growth factor 23 (FGF23) levels have a significant association with left ventricular hypertrophy (LVH). Although LVH is commonly seen in hypertensive patients, the association between FGF23, hypertension, and LVH remains unclear. We aimed to examine the changes in serum and intracardiac FGF23 during the progression of hypertension using spontaneously hypertensive rats (SHR).

METHODS

Male SHR comprised the experimental group (HT group) and Wistar Kyoto rats served as controls. At 10 weeks, urinary and blood biochemical analyses and blood pressure measurements were performed for both the groups. At 18 weeks, the rats were sacrificed: urinary and blood biochemical analyses and real-time PCR were performed.

RESULTS

At 18 weeks, the relative heart weight and serum N-terminal pro-brain natriuretic peptide and aldosterone levels were significantly greater in the HT group. Serum calcium and phosphate levels were significantly lower, while serum FGF23 levels were significantly higher in the HT group compared to the control group. Further analyses showed that the mRNA expression of FGF23 in the heart was significantly increased in the HT group compared to the control group. Both serum FGF23 levels and intracardiac mRNA expression of FGF23 showed significant correlation with the relative heart weight.

CONCLUSIONS

During LVH progression, serum and intracardiac FGF23 increased in hypertension. Although it is unclear whether the change in FGF23 is the cause or result of LVH, the interaction between FGF23 and aldosterone may be associated with the development of LVH in hypertension.

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.

Hypertension in patients on dialysis: diagnosis, mechanisms, and management

Hypertension (blood pressure > 140/90 mm Hg) is very common in patients undergoing regular dialysis, with a prevalence of 70-80%, and only the minority has adequate blood pressure (BP) control. In contrast to the unclear association of predialytic BP recordings with cardiovascular mortality, prospective studies showed that interdialytic BP, recorded as home BP or by ambulatory blood pressure monitoring in hemodialysis patients, associates more closely with mortality and cardiovascular events. Although BP is measured frequently in the dialysis treatment environment, aspects related to the measurement technique traditionally employed may be unsatisfactory. Several other tools are now available and being used in clinical trials and in clinical practice to evaluate and treat elevated BP in chronic kidney disease (CKD) patients. While we wait for the ongoing review of the CKD Blood Pressure KIDGO guidelines, there is no guideline for the dialysis population addressing this important issue. Thus, the objective of this review is to provide a critical analysis of the information available on the epidemiology, pathogenic mechanisms, and the main pillars involved in the management of blood pressure in stage 5-D CKD, based on current knowledge.

What happens to the heart in chronic kidney disease?

Cardiovascular disease is common in patients with chronic kidney disease. The increased risk of cardiovascular disease seen in this population is attributable to both traditional and novel vascular risk factors. Risk of sudden cardiac or arrhythmogenic death is greatly exaggerated in chronic kidney disease, particularly in patients with end stage renal disease where the risk is roughly 20 times that of the general population. The reasons for this increased risk are not entirely understood and while atherosclerosis is accelerated in the presence of chronic kidney disease, premature myocardial infarction does not solely account for the excess risk. Recent work demonstrates that the structure and function of the heart starts to alter early in chronic kidney disease, independent of other risk factors. The implications of cardiac remodelling and hypertrophy may predispose chronic kidney disease patients to heart failure, arrhythmia and myocardial ischaemia. Further research is needed to minimise cardiovascular risk associated with structural and functional heart disease associated with chronic kidney disease.

Spironolactone is effective in treating hypokalemia among peritoneal dialysis patients

BACKGROUND

Hypokalemia is common in peritoneal dialysis (PD) patients and is associated with increased cardiovascular and all-cause mortality. The management approach for such patients routinely includes spironolactone at our centre. We undertook this study to assess the efficacy of spironolactone for the treatment of hypokalemia in PD patients.

METHODS

Retrospective chart review of PD patients at a single centre. Serum potassium was compared prior to initiation of spironolactone and two months afterwards. Indication for spironolactone and changes in blood pressure (BP), weight, and serum creatinine were also recorded.

RESULTS

The chart review identified 53 patients who fit our selection criteria. The mean age was 64 +/- 15 years and the majority was treated with continuous cyclic peritoneal dialysis. Serum potassium rose from 3.7 +/- 0.5 to 4.2 +/- 0.5 mmol/L (P<0.0001) after 2 months with a mean dose of spironolactone of 28.5+/-15.2 mg (median dose 25 mg). A significant reduction in systolic BP was observed from 150+/- 18 to 137 +/-24 (P = 0.002); a non- significant reduction in diastolic BP was also observed. The rise in potassium was constant in the range of 0.4 to 0.5 mmol/L regardless of whether spironolactone was initiated for hypokalemia, diuresis, or as an antihypertensive. There was no change in serum creatinine or body weight two months after introduction of spironolactone.

CONCLUSIONS

Spironolactone is safe and effective in treating hypokalemia in PD patients. It is also an effective antihypertensive agent and merits further study in the PD population.

Mineralocorticoid Receptor Blockade in End-Stage Renal Disease

PURPOSE OF REVIEW

The purpose of this study was to summarize recent findings about cardiovascular benefits and safety of aldosterone blockade in patients with end-stage renal disease (ESRD).

RECENT FINDINGS

It is now well recognized that aldosterone's deleterious cardiovascular impact is not limited to its pressor effect arising from an increase in sodium reabsorption in the kidneys. Aldosterone has also been shown to increase blood pressure by a direct activation of the sympathetic nervous system, to cause endothelial and vascular smooth muscle cell dysfunction, myocardial remodeling and fibrosis, and to have pro-arrhythmogenic actions in the heart. These unconventional extra-renal effects of aldosterone make its blockade feasible and potentially beneficial for patients with ESRD. Accumulating data support the idea that aldosterone antagonism leads to a better blood pressure control, reduction in left ventricular (LV) mass, improved LV function, and reduced all-cause and cardiovascular mortality in ESRD patients. Reassuringly, rates of major adverse events, especially, significant hyperkalemia-the most feared adverse consequence-were low with careful patient selection and monitoring.

Aldosterone antagonist therapy and its relationship with inflammation, fibrosis, thrombosis, mineral-bone disorder and cardiovascular complications in peritoneal dialysis (PD) patients

Background

High aldosterone level may contribute to pathogenesis of hypertension, vessels damage and cardiovascular system deterioration in chronic kidney disease patients. Besides its classical action via mineralocorticoid receptor, aldosterone is also involved in cell growth, inflammation, oxidative stress, endothelial dysfunction and exerts fibroproliferative effects. The aim of the study was to assess whether aldosterone antagonist treatment may influence serum level of inflammatory, fibrosis, thrombosis and mineral-bone metabolism markers in peritoneal dialysis (PD) patients and blood pressure, aortic stiffness, echocardiographic indices after 12 months of treatment.

Methods

Twenty-two patients on PD were assigned to spironolactone treatment in dose of 50 mg daily during 12 months. Fifteen PD patients were assigned to control group. Echocardiographic indices, PVW, SBP, DBP (mean values from ABPM) and biochemical parameters such as: aldosterone, osteopontin, IL-6, selectin-P, TGF-β, PTH, MMP-2 were performed at the beginning and after 12 months in spironolactone and control group.

Results

There were no statistically significant differences in echocardiographic indices, PWV, BP (ABPM readings) and biochemical markers: MMP-2, serum aldosterone, TGF-β, IL-6, selectin-P, PTH level after 12 months of spironolactone treatment. There was statistically significant rise in osteopontin level after 12 months of spironolactone treatment. Episodes of life-threatening hyperkalemia were not reported.

Conclusions

Aldosterone antagonists use in PD patients seems to be safe. Longer duration or higher dosage of spironolactone seems to be more effective in improving cardiovascular system status in PD patients. Further studies are required to determine relationship between mineralocorticoid receptor blockade and mineral-bone disturbances in PD patients.

Pharmacotherapy of Hypertension in Chronic Dialysis Patients

Among patients on dialysis, hypertension is highly prevalent and contributes to the high burden of cardiovascular morbidity and mortality. Strict volume control via sodium restriction and probing of dry weight are first-line approaches for the treatment of hypertension in this population; however, antihypertensive drug therapy is often needed to control BP. Few trials compare head-to-head the superiority of one antihypertensive drug class over another with respect to improving BP control or altering cardiovascular outcomes; accordingly, selection of the appropriate antihypertensive regimen should be individualized. To individualize therapy, consideration should be given to intra- and interdialytic pharmacokinetics, effect on cardiovascular reflexes, ability to treat comorbid illnesses, and adverse effect profile. β-Blockers followed by dihydropyridine calcium-channel blockers are our first- and second-line choices for antihypertensive drug use. Angiotensin-converting enzyme inhibitors and angiotensin receptor blockers seem to be reasonable third-line choices, because the evidence base to support their use in patients on dialysis is sparse. Add-on therapy with mineralocorticoid receptor antagonists in specific subgroups of patients on dialysis (i.e., those with severe congestive heart failure) seems to be another promising option in anticipation of the ongoing trials evaluating their efficacy and safety. Adequately powered, multicenter, randomized trials evaluating hard cardiovascular end points are urgently warranted to elucidate the comparative effectiveness of antihypertensive drug classes in patients on dialysis. In this review, we provide an overview of the randomized evidence on pharmacotherapy of hypertension in patients on dialysis, and we conclude with suggestions for future research to address critical gaps in this important area.