A Comparative Study of Carvedilol Versus Metoprolol Initiation and 1-Year Mortality Among Individuals Receiving Maintenance Hemodialysis

I Brazilian guideline on hypertension in dialysis of the Brazilian Society of Nephrology

Hypertension in dialysis patients (HTND) has a high prevalence, affecting at least 80% or more of patients, and its management in the nephrology practice is heterogeneous and often empirical. Knowing how to define, understand the pathophysiology, diagnose, monitor and treat with lifestyle changes, and adjust antihypertensive drugs to achieve the recommended blood pressure (BP) target - to reduce morbidity and mortality - requires specific knowl-edge and approaches within the contexts of hemodialysis (HD) and peritoneal dialysis (PD). This document is the first guideline of the Brazilian Society of Nephrology, developed by the departments of Hypertension and Dialysis. It aims to guide physicians who provide care in dialysis centers on how to manage patients with HTND, in a comprehensive and individualized manner, based on the critical appraisal of the best available scientific evidence. When such evidence is scarce or unavailable, the opinion of specialists should be recommended. The different topics covered include HTND definition (pre-HD BP ≥ 140/90 mmHg and post-HD BP ≥ 130/80 mmHg), epidemiology, and pathophysiology; diagnosis of HTND preferably with BP measurements outside the dialysis setting (BP ≥ 130/80 mmHg); complementary assessment; blood pressure targets; non-pharmacological treatment; use of the most appropriate antihypertensive medications; special situations; and complications of HTND, predominantly cardiovascular ones.

Comparison of β-blocker agents and mortality in maintenance hemodialysis patients: an international cohort study

Background

Despite a lack of clinical trial data, β-blockers are widely prescribed to dialysis patients. Whether specific β-blocker agents are associated with improved long-term outcomes compared with alternative β-blocker agents in the dialysis population remains uncertain.

Methods

We analyzed data from an international cohort study of 10 125 patients on maintenance hemodialysis across 18 countries that were newly prescribed a β-blocker medication within the Dialysis Outcomes and Practice Patterns Study (DOPPS). The following β-blocker agents were compared: metoprolol, atenolol, bisoprolol and carvedilol. Multivariable Cox proportional hazards models were used to estimate the association between the newly prescribed β-blocker agent and all-cause mortality. Stratified analyses were performed on patients with and without a prior history of cardiovascular disease.

Results

The mean (standard deviation) age in the cohort was 63 (15) years and 57% of participants were male. The most commonly prescribed β-blocker agent was metoprolol (49%), followed by carvedilol (29%), atenolol (11%) and bisoprolol (11%). Compared with metoprolol, atenolol {adjusted hazard ratio (HR) 0.77 [95% confidence interval (CI) 0.65-0.90]} was associated with a lower mortality risk. There was no difference in mortality risk with bisoprolol [adjusted HR 0.99 (95% CI 0.82-1.20)] or carvedilol [adjusted HR 0.95 (95% CI 0.82-1.09)] compared with metoprolol. These results were consistent upon stratification of patients by presence or absence of a prior history of cardiovascular disease.

Conclusions

Among patients on maintenance hemodialysis who were newly prescribed β-blocker medications, atenolol was associated with the lowest mortality risk compared with alternative agents.

Role of β-blockers in the cardiovascular disease continuum: a collaborative Delphi survey-based consensus from Asia-Pacific

OBJECTIVE

This Delphi method of consensus was designed to develop scientific statements for β-blockers in the continuum of cardiovascular diseases with a special focus on the role of bisoprolol.

METHODS

Eleven experienced cardiologists from across the Asia-Pacific countries participated in two rounds of the survey. In the first round, experts were asked to rate agreement/disagreement with 35 statements across seven domains regarding the use of β-blockers for treating hypertension, heart failure, coronary artery diseases, co-morbidities, as well as their safety profile, usage pattern, and pharmacokinetic variability. A consensus for a statement could be reached with >70% agreement.

RESULTS

Except for seven statements, all attained consensus in the first round. In the second round that was conducted virtually, the experts re-appraised their ratings for the seven statements along with a critical appraisal of two additional statements that were suggested by experts in the preceding round. At the end of the second round, the final version included 36 statements (34 original statements, two statements suggested by experts, and the omission of one statement that did not attain consensus). The final version of statements in the second round was disseminated among experts for their approval followed by manuscript development.

CONCLUSION

Attainment of consensus for almost all statements reconfirms the clinical benefits of β-blockers, particularly β1-selective blockers for the entire spectrum of cardiovascular diseases.

Influence of Different Types of β-Blockers on Mortality in Patients on Hemodialysis

Previous results regarding the association between types of β-blockers and outcomes in patients on hemodialysis (HD) were inconsistent. Our study aimed to evaluate patient survival according to the type of β-blockers administered using a large sample of patients with maintenance HD. Our study included patients on maintenance HD patients from a national HD quality assessment program (n = 54,132). We divided included patients into four groups based on their use and type; Group 1 included patients without a prescription of β-blockers, Group 2 included patients with a prescription of dialyzable and cardioselective β-blockers, Group 3 included patients with a prescription of non-dialyzable and non-cardioselective β-blockers, and Group 4 included patients with prescription of non-dialyzable and cardioselective β-blockers. The number of patients in Groups 1, 2, 3, and 4 were 34,514, 2789, 15,808, and 1021, respectively. The 5-year survival rates in Groups 1, 2, 3, and 4 were 69.3%, 66.0%, 68.8%, and 69.2%, respectively. Univariate Cox regression analyses showed the hazard ratios to be 1.10 (95% CI, 1.04-1.17) in Group 2 and 1.05 (95% CI, 1.02-1.09) in Group 3 compared to Group 1. However, multivariate Cox regression analyses did not show statistical significance among the four groups. Our study showed that there was no significant difference in patient survival based on the use or types of β-blockers.

Current Knowledge of Beta-Blockers in Chronic Hemodialysis Patients

Beta-blockers include a large spectrum of drugs with various specific characteristics, and a well-known cardioprotective efficacy. They are recommended in heart failure, hypertension and arrhythmia. Their use in chronic hemodialysis patients is still controversial, mainly because of the lack of specific randomized clinical trials. Large observational studies and two important clinical trials have reported almost unanimously their efficacy in chronic hemodialysis patients, which seems to be related to their levels of dialyzability and cardioselectivity. A recent meta-analysis suggested that high dialyzable beta-blockers are correlated to a reduced risk of all-cause mortality and cardiovascular complications compared with low dialyzable beta-blockers. Despite their benefits, beta-blockers may have adverse effects, such as intradialytic hypotension with low dialyzability beta-blockers or the risk of sub-therapeutic plasma concentration of high dialyzable ones during dialysis sessions. Both cases are linked to adverse cardiovascular events. A solution for both high and low dialyzable drugs could be their administration after dialysis sessions. Futhermore, the bulk of existing literature seems to favor cardioselective beta-blockers with moderate-to-high dialyzability as the ideal agents in dialysis patients, but further, larger studies are needed. This review aims to analyze beta-blockers' characteristics, indications and evidence-based role in chronic hemodialysis patients.

Prevention of Intradialytic Hypotension in Hemodialysis Patients: Current Challenges and Future Prospects

Intradialytic hypotension, defined as rapid decrease in systolic blood pressure of greater than or equal to 20 mmHg or in mean arterial pressure of greater than or equal to 10 mmHg that results in end-organ ischemia and requires countermeasures such as ultrafiltration reduction or saline infusion to increase blood pressure to improve patient's symptoms, is a known complication of hemodialysis and is associated with several potential adverse outcomes. Its pathogenesis is complex and involves both patient-related factors such as age and comorbidities, as well as factors related to the dialysis prescription itself. Key factors include the need for volume removal during hemodialysis and a suboptimal vascular response which compromises the ability to compensate for acute intravascular volume loss. Inadequate vascular refill, incorrect assessment or unaccounted changes of target weight, acute illnesses and medication interference are further potential contributors. Intradialytic hypotension can lead to compromised tissue perfusion and end-organ damage, both acutely and over time, resulting in repetitive injuries. To address these problems, a careful assessment of subjective symptoms, minimizing interdialytic weight gains, individualizing dialysis prescription and adjusting the dialysis procedure based on patients' risk factors can mitigate negative outcomes.

β-Blockers could improve the 28-day and 3-year survival of patients with end-stage renal disease: a retrospective cohort study

BACKGROUND

Dialysis or non-dialysis end-stage renal disease (ESRD) patients are accompanied by cardiovascular disease (CVD) or hypertension. We aimed to study the effect of a common treatment for CVD, β-blockers, on the survival of ESRD patients, improving their prognosis from the perspective of drug therapy.

METHODS

It was a retrospective cohort study using the Medical Information Mart for Intensive Care dataset. ESRD patients in the intensive care unit from June 2001 to October 2012 were included. We examined the effect of using versus not using β-blockers in the overall population and subgroups with the risk of 28-day and 3-year mortality through Cox proportional hazards models and Kaplan-Meier curves.

RESULTS

A total of 1639 participants were included with 371 (22.64%) β-blockers users. There were 315 (19.22%) 28-day and 970 (59.18%) 3-year mortality events during follow-up. Using β-blockers in overall ESRD patients could reduce all-cause 28-day mortality [adjusted hazard ratio (HR) 0.450, 95% confidence interval (CI) 0.325-0.624] and 3-year mortality (adjusted HR 0.695, 95% CI 0.589-0.821). This result was consistent among subgroups (ESRD without hypertension: adjusted HR 0.412, 95% CI 0.289-0.588; with CVD: adjusted HR 0.478, 95% CI 0.321-0.711; without CVD: adjusted HR 0.448, 95% CI 0.248-0.810; with dialysis: adjusted HR 0.471, 95% CI 0.320-0.694) in 28-day mortality, and the 3-year mortality was consistent. In ESRD patients with hypertension and without dialysis subgroups, β-blockers had no effect on survival.

CONCLUSION

Using β-blockers could reduce the risk of 28-day and 3-year mortality in ESRD patients, including those with CVD. This study provided a reference for the treatment of β-blockers in patients with ESRD.

Why is Intradialytic Hypotension the Commonest Complication of Outpatient Dialysis Treatments?

Intradialytic hypotension (IDH) is the most frequent complication of hemodialysis (HD) treatments with a frequency of 10% to 12% for patients with chronic kidney disease attending for outpatient treatments and is associated with both temporary ischemic stress to vital organs, including the heart and brain, and increased patient mortality. Although there have been many different definitions of IDH over the years, an absolute nadir systolic blood pressure (SBP) has the strongest association with patient outcomes. The unifying pathophysiology is one of reduced effective blood volume, resulting in lower plasma tonicity, and if this cannot be adequately compensated for by activation of neurohumeral systems, then arteriolar tone and blood pressure fall. The risk factors for developing IDH are numerous, ranging from patient-related factors, including age and comorbidity with reduced cardiac reserve, to patient compliance with dietary and lifestyle advice, to reactions with the extracorporeal circuit and medications, choice of dialysate composition and temperature, setting of postdialysis target weight, ultrafiltration rate, and profiling. Advances in dialysis machine technology by providing real time estimates of the effective circulating volume and adjusting dialysate composition to maintain vascular tonicity are being developed, but currently require more sophisticated biofeedback loops to be clinically effective in preventing IDH. While awaiting advances in artificial intelligence, the clinician continues to rely on patient education to limit interdialytic weight gains, frequent assessment of the postdialysis target weight, adjusting dialysate composition and temperature, introducing convective therapies to increase thermal losses, and altering dialysis session duration and frequency to reduce ultrafiltration rate requirements.

Blood pressure, arterial waveform, and arterial stiffness during hemodialysis and their clinical implications in intradialytic hypotension

This study included 152 hemodialysis patients (mean age, 69 years; 34.2% female) and investigated serial changes in blood pressure (BP) and arterial stiffness indices during hemodialysis using an oscillometric device, SphygmoCor XCEL, and examined whether assessment of the arterial waveform has clinical implications for the management of intradialytic hypotension (IDH). Measurement was performed every 30 min during hemodialysis, and the threshold defining IDH was systolic BP (SBP) decrease ≥40 mmHg or a requirement for antihypotensive medication in all patients and ≥ the 75th percentile of maximum SBP decrease during hemodialysis (≥34 mmHg) in the subgroup without antihypotensive medication (n = 98). In all patients, a 1-standard deviation (SD) increase in the baseline subendocardial viability ratio (SEVR), an index of myocardial perfusion, was an independent predictor of IDH (odds ratio [OR] 0.43, p < 0.001). In the subgroup analysis, a serial change in SBP and all arterial waveform indices, including the augmentation index, augmented pressure (AP), and SEVR, during hemodialysis were greater for IDH than for non-IDH patients (all p < 0.01 by 2-way repeated-measures ANOVA), with the exception of heart rate (p = 0.40) and diastolic pressure time index (p = 0.21). Diabetes (OR 4.08), a 1-SD increase in ultrafiltration rate (OR 2.07), fractional shortening (OR 0.45), baseline SEVR (OR 0.36) and the first 1-h percent change in AP (OR 0.52) were independent predictors of IDH (all p < 0.05). In conclusion, impaired myocardial perfusion and increased arterial stiffness, particularly poor arteriolar responsiveness to acute dialysis-related changes, are associated with IDH, and predialysis SEVR evaluation can complement screening for IDH.

Chitosan-Based Scaffolds for the Treatment of Myocardial Infarction: A Systematic Review

Cardiovascular diseases (CVD), such as myocardial infarction (MI), constitute one of the world's leading causes of annual deaths. This cardiomyopathy generates a tissue scar with poor anatomical properties and cell necrosis that can lead to heart failure. Necrotic tissue repair is required through pharmaceutical or surgical treatments to avoid such loss, which has associated adverse collateral effects. However, to recover the infarcted myocardial tissue, biopolymer-based scaffolds are used as safer alternative treatments with fewer side effects due to their biocompatibility, chemical adaptability and biodegradability. For this reason, a systematic review of the literature from the last five years on the production and application of chitosan scaffolds for the reconstructive engineering of myocardial tissue was carried out. Seventy-five records were included for review using the "preferred reporting items for systematic reviews and meta-analyses" data collection strategy. It was observed that the chitosan scaffolds have a remarkable capacity for restoring the essential functions of the heart through the mimicry of its physiological environment and with a controlled porosity that allows for the exchange of nutrients, the improvement of the electrical conductivity and the stimulation of cell differentiation of the stem cells. In addition, the chitosan scaffolds can significantly improve angiogenesis in the infarcted tissue by stimulating the production of the glycoprotein receptors of the vascular endothelial growth factor (VEGF) family. Therefore, the possible mechanisms of action of the chitosan scaffolds on cardiomyocytes and stem cells were analyzed. For all the advantages observed, it is considered that the treatment of MI with the chitosan scaffolds is promising, showing multiple advantages within the regenerative therapies of CVD.

Managing Heart Failure in Patients on Dialysis: State-of-the-Art Review

Heart failure (HF) and end-stage kidney disease (ESKD) frequently coexist; 1 comorbidity worsens the prognosis of the other. HF is responsible for almost half the deaths of patients on dialysis. Despite patients' with ESKD composing an extremely high-risk population, they have been largely excluded from landmark clinical trials of HF, and there is, thus, a paucity of data regarding the management of HF in patients on dialysis, and most of the available evidence is observational. Likewise, in clinical practice, guideline-directed medical therapy for HF is often down-titrated or discontinued in patients with ESKD who are undergoing dialysis; this is due to concerns about safety and tolerability. In this state-of-the-art review, we discuss the available evidence for each of the foundational HF therapies in ESKD, review current challenges and barriers to managing patients with HF on dialysis, and outline future directions to optimize the management of HF in these high-risk patients.

Impact of type of dialyzable beta-blockers on subsequent risk of mortality in patients receiving dialysis: A systematic review and meta-analysis

BACKGROUND

Beta-blockers has been reported to improve all-cause mortality and cardiovascular mortality in patients receiving dialysis, but type of beta-blockers (i.e., high vs. low dialyzable) on patient outcomes remains unknown. This study aimed at assessing the outcomes of patients receiving dialyzable beta-blockers (DBBs) compared to those receiving non-dialyzable beta-blockers (NDBBs).

METHODS

We searched the databases including PubMed, Embase, Cochrane, and ClinicalTrials.gov until 28 February 2022 to identify articles investigating the impact of DBBs/NDBBs among patients with renal failure receiving hemodialysis/peritoneal dialysis (HD/PD). The primary outcome was risks of all-cause mortality, while the secondary outcomes included risk of overall major adverse cardiac event (MACE), acute myocardial infarction (AMI) and heart failure (HF). We rated the certainty of evidence (COE) by Cochrane methods and the GRADE approach.

RESULTS

Analysis of four observational studies including 75,193 individuals undergoing dialysis in hospital and community settings after a follow-up from 180 days to six years showed an overall all-cause mortality rate of 11.56% (DBBs and NDBBs: 12.32% and 10.7%, respectively) without significant differences in risks of mortality between the two groups [random effect, aHR 0.91 (95% CI, 0.81-1.02), p = 0.11], overall MACE [OR 1.03 (95% CI, 0.78-1.38), p = 0.82], and AMI [OR 1.02 (95% CI, 0.94-1.1), p = 0.66]. Nevertheless, the pooled odds ratio of HF among patients receiving DBBs was lower than those receiving NDBB [random effect, OR 0.87 (95% CI, 0.82-0.93), p<0.001]. The COE was considered low for overall MACE, AMI and HF, while it was deemed moderate for all-cause mortality.

CONCLUSIONS

The use of dialyzable and non-dialyzable beta-blockers had no impact on the risk of all-cause mortality, overall MACE, and AMI among dialysis patients. However, DBBs were associated with significant reduction in risk of HF compared with NDBBs. The limited number of available studies warranted further large-scale clinical investigations to support our findings.

Cardio-selective versus non-selective β-blockers for cardiovascular events and mortality in long-term dialysis patients: A systematic review and meta-analysis

BACKGROUND

Trials in patients receiving dialysis have demonstrated that β-blockers reduce all-cause mortality and cardiovascular events. However, differences still exist within-class comparative effectiveness studies of the therapeutic benefits of β-blockers in dialysis patients.

OBJECTIVE

The purpose of this systematic review is to examine whether cardiovascular events and all-cause mortality differed between dialysis patients receiving cardio-selective and non-selective agents.

METHODS

A comprehensive search of relevant articles from the PubMed, EMBASE, Cochrane Central Register and ClinicalTrials.gov was performed up to September 4, 2022, we included adults receiving β-blockers to evaluate the effects of cardio-selective versus non-selective agents on mortality and cardiovascular events in the dialysis population. Hazard ratios (HRs) and 95% confidence intervals (CIs) were examined for the negative outcomes of cardiovascular events and death for any reason. The risk of bias in randomized controlled trials (RCTs) was assessed using Cochrane's risk of bias tool and the risk of bias in observational studies was assessed using a table designed according to the ROBINS-I tool, the evidence grade was assessed using the GRADE guideline. For all-cause mortality and cardiovascular events, the RevMan software (version 5.3) was used to calculate pooled HRs with 95% CI. The heterogeneity (I2) in statistics was used to examine the degree of heterogeneity among studies.

RESULTS

Four observational studies, including 58, 652 long-term dialysis patients, were included in the meta-analysis. Compared to dialysis patients who took non-selective β-blockers, who took cardio-selective β-blockers was probably associated with fewer cardiovascular events (hazard ratio [HR] = 0.85, 95% confidence interval [CI] = 0.81, 0.89, heterogeneity [I2] = 0%, three trials, 52,077 participants, moderate-quality evidence) and may have lower all-cause mortality (HR = 0.83, 95% CI = 0.69, 0.99, I2 = 91%, four trials, 54,115 participants, low-quality evidence).

CONCLUSIONS

This systematic review showed that cardio-selective β-blockers are probably associated with fewer cardiovascular events and may have lower all-cause mortality in long-term dialysis patients than non-selective β-blockers. The present study results need to be replicated using randomized controlled trials with longer observation durations.

Frequency of Intradialytic Hypertension Using Kidney Disease: Improving Global Outcomes (KDIGO) Suggested Definition in a Single Hemodialysis Centre in Pakistan

OBJECTIVES

 To estimate the frequency of intradialytic hypertension (IDH) in our centre as per the definition suggested by Kidney Disease: Improving Global Outcomes (KDIGO).

METHODS

 A cross-sectional study was conducted at the dialysis department of The Kidney Centre Post Graduate Training Institute (PGTI) Karachi, Pakistan from August 2021 to October 2021 among 263 end-stage kidney disease (ESKD) patients on maintenance hemodialysis (MHD) aged ≥ 18 years of both genders. The study outcome was the frequency of IDH as per the latest KDIGO suggested definition i.e., systolic blood pressure (SBP) rise of > 10 mm Hg from pre- to post-dialysis within the hypertensive range in at least four out of six consecutive dialysis treatments. Frequencies (%) and mean (±SD) were calculated for categorical and continuous variables respectively, using SPSS version 21 (IBM Corp., Armonk, NY, USA).

RESULTS

 Among 263 patients, the mean age was 51.02 (±14.1) years and 56.3% were males. Around 30.8% of patients were dialysis-dependent for 1.1 to three years. The most common comorbidity was hypertension (88.6%). Standard dialysate calcium of 3mEq/l was received by 91.6% of study participants. About 78.7% of patients were using antihypertensive(s), out of which 85.5% were compliant and 37.6% were using a single antihypertensive. The most common antihypertensive in use was beta-blockers (78.3%). Around 16% of patients were found to have IDH. Age of the patients was significantly associated with IDH (p=0.038). The majority of the patients with IDH were those who were taking anti-hypertension medications as compared to the patients who were not taking them (p <0.004). Interdialytic weight gain was not a significant predictor for IDH.

CONCLUSION

 The frequency of IDH was 16% according to the latest suggested KDIGO definition. This is much lower than regional and global estimates according to earlier definitions. There is a dire need to establish a standardized definition of IDH in guidelines to diagnose, manage and compare data. Also, the association of IDH with fluid overload is not found in our study which emphasizes the need to evaluate other causative factors.

Executive summary of the Korean Society of Nephrology 2021 clinical practice guideline for optimal hemodialysis treatment

The Korean Society of Nephrology (KSN) has published a clinical practice guideline (CPG) document for maintenance hemodialysis (HD). The document, 2021 Clinical Practice Guideline on Optimal HD Treatment, is based on an extensive evidence-oriented review of the benefits of preparation, initiation, and maintenance therapy for HD, with the participation of representative experts from the KSN under the methodologists' support for guideline development. It was intended to help clinicians participating in HD treatment make safer and more effective clinical decisions by providing user-friendly guidelines. We hope that this CPG will be meaningful as a recommendation in practice, but not on a regulatory rule basis, as different approaches and treatments may be used by health care providers depending on the individual patient's condition. This CPG consists of eight sections and 15 key questions. Each begins with statements that are graded by the strength of recommendations and quality of the evidence. Each statement is followed by a summary of the evidence supporting the recommendations. There are also a link to full-text documents and lists of the most important reports so that the readers can read further (most of this is available online).

β-Blocker Use and Cardiovascular Outcomes in Hemodialysis: A Systematic Review

Rationale & Objective

There is conflicting evidence regarding the type of β-blockers to use in dialysis patients. This systematic review seeks to determine whether highly dialyzable β-blockers are associated with higher rates of cardiovascular events and mortality in hemodialysis patients than poorly dialyzable β-blockers.

Study Design

A systematic review of the existing literature was conducted. A meta-analysis was performed using data from the selected studies.

Setting & Study Populations

Participants were from the United States, Canada, and Taiwan. The mean ages of participants ranged from 55.9-75.7 years.

Selection Criteria for Studies

We searched the Ovid MEDLINE database from 1990 to September 2020. Studies without adult hemodialysis participants and without comparisons of at least 2 β-blockers of different dialyzability were excluded.

Data Extraction

Baseline and adjusted outcome data were extracted from each study.

Analytical Approach

Random-effects models were used to calculate pooled risk ratios using fully adjusted models from individual studies.

Results

Four cohort studies were included. Pooling fully adjusted models, highly dialyzable β-blockers did not influence mortality (HR, 0.94; 95% CI, 0.81-1.08; I² = 0.84) compared with poorly dialyzable β-blockers but were associated with a reduction in cardiovascular events (HR, 0.88; 95% CI, 0.83-0.93). There was significant heterogeneity between studies (I² = 0.35). Only 1 study reported on adverse events. Intradialytic hypotension was more common in those on carvedilol (a poorly dialyzable β-blocker) compared with those on metoprolol (a highly dialyzable β-blocker; adjusted incidence rate ratio, 1.10; 95% CI, 1.09-1.11).

Limitations

No randomized controlled trials were identified. Each study used different analytic methods and different definitions for outcomes. Classifications of β-blockers varied. Only 1 study reported on adverse events.

Conclusions

Pooled data suggest highly dialyzable β-blockers are associated with similar mortality events and fewer cardiovascular events compared with poorly dialyzable β-blockers.

Insights into Concomitant Atrial Fibrillation and Chronic Kidney Disease

Chronic kidney disease (CKD) shows a high prevalence and is characterized by progressive and irreversible loss of renal function. It is also associated with a high risk of cardiovascular disease. The CKD population often suffers from atrial fibrillation (AF), which is associated with cardiovascular and all-cause mortality. There is a pernicious bidirectional relationship between CKD and AF: renal dysfunction can help promote AF initiation and maintenance, while unmanageable AF often accelerates kidney function deterioration. Therefore, it is necessary to determine the interactive mechanisms between CKD and AF for optimal management of patients. However, due to renal function impairment and changes in the pharmacokinetics of anticoagulants, it is still elusive to formulate a normative therapeutic schedule for the AF population concomitant with CKD especially those with end-stage kidney failure. This review describes the possible molecular mechanisms linking CKD to AF and existing therapeutic options.

Executive Summary of the Korean Society of Nephrology 2021 Clinical Practice Guideline for Optimal Hemodialysis Treatment

The Korean Society of Nephrology (KSN) has published a clinical practice guideline (CPG) document for maintenance hemodialysis (HD). The document, 2021 Clinical Practice Guideline on Optimal HD Treatment, is based on an extensive evidence-oriented review of the benefits of preparation, initiation, and maintenance therapy for HD, with the participation of representative experts from the KSN under the methodologists’ support for guideline development. It was intended to help clinicians participating in HD treatment make safer and more effective clinical decisions by providing user-friendly guidelines. We hope that this CPG will be meaningful as a recommendation in practice, but not on a regulatory rule basis, as different approaches and treatments may be used by health care providers depending on the individual patient’s condition. This CPG consists of eight sections and 15 key questions. Each begins with statements that are graded by the strength of recommendations and quality of the evidence. Each statement is followed by a summary of the evidence supporting the recommendations. There is also a link to full-text documents and lists of the most important reports so that the readers can read further (most of this is available online).

An Integrative Pharmacology-Based Strategy to Uncover the Mechanism of Xiong-Pi-Fang in Treating Coronary Heart Disease with Depression

Objectives: This study aimed to explore the mechanism of Xiong-Pi-Fang (XPF) in the treatment of coronary heart disease (CHD) with depression by an integrative strategy combining serum pharmacochemistry, network pharmacology analysis, and experimental validation. Methods: An ultrahigh performance liquid chromatography-quadrupole-time-of-flight tandem mass spectrometry (UPLC-Q-TOF/MS) method was constructed to identify compounds in rat serum after oral administration of XPF, and a component-target network was established using Cytoscape, between the targets of XPF ingredients and CHD with depression. Furthermore, Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses were performed to deduce the mechanism of XPF in treating CHD with depression. Finally, in a chronic unpredictable mild stress (CUMS)-and isoproterenol (ISO)-induced rat model, TUNEL was used to detect the apoptosis index of the myocardium and hippocampus, ELISA and western blot were used to detect the predicted hub targets, namely AngII, 5-HT, cAMP, PKA, CREB, BDNF, Bcl-2, Bax, Cyt-c, and caspase-3. Results: We identified 51 compounds in rat serum after oral administration of XPF, which mainly included phenolic acids, saponins, and flavonoids. Network pharmacology analysis revealed that XPF may regulate targets, such as ACE2, HTR1A, HTR2A, AKT1, PKIA, CREB1, BDNF, BCL2, BAX, CASP3, cAMP signaling pathway, and cell apoptosis process in the treatment of CHD with depression. ELISA analysis showed that XPF decreased Ang-II content in the circulation and central nervous system, inhibited 5-HT levels in peripheral circulation, and increased 5-HT content in the central nervous system and cAMP content in the myocardia and hippocampus. Meanwhile, western blot analysis indicated that XPF could upregulate the expression levels of PKA, CREB, and BDNF both in the myocardia and hippocampus. TUNEL staining indicated that the apoptosis index of myocardial and hippocampal cells increased in CUMS-and ISO-induced CHD in rats under depression, and XPF could increase the expression of Bcl-2, inhibit the expression of Bax, Cyt-c, and caspase-3, and rectify the injury of the hippocampus and myocardium, which exerted antidepressant and antimyocardial ischemia effects. Conclusion: Our study proposed an integrated strategy, combining serum pharmacochemistry and network pharmacology to investigate the mechanisms of XPF in treating CHD with depression. The mechanism of XPF in treating CHD with depression may be related to the activation of the cAMP signaling pathway and the inhibition of the apoptosis.

β-blocker dialyzability and the risk of mortality and cardiovascular events in patients undergoing hemodialysis

BACKGROUND

β-blocker (BB) dialyzability has been proposed to limit their efficacy among hemodialysis (HD) patients. We attempted to confirm this hypothesis by comparing health outcomes associated with the initiation of dialyzable or nondialyzable BBs in a nationwide cohort of HD patients.

METHODS

We created a prospective cohort study of 15 699 HD patients who initiated dialyzable BBs (atenolol, acebutolol, metoprolol and bisoprolol) and 20 904 hemodialysis patients who initiated nondialyzable BBs (betaxolol, carvedilol and propranolol) between 2004 and 2011 in Taiwan healthcare. We compared the risk of all-cause mortality and major adverse cardiovascular events (MACEs, a composite of the acute coronary syndrome, ischemic stroke and heart failure) between users of dialyzable versus nondialyzable BBs during a 2-year follow-up.

RESULTS

New users of dialyzable BBs were younger, more often men, with diabetes mellitus, hypertension and hyperlipidemia compared with users of nondialyzable BBs. Compared with nondialyzable BBs, initiation of dialyzable BBs was associated with lower all-cause mortality {hazard ratio [HR] 0.82 [95% confidence interval (CI) 0.75-0.88]} and lower risk of MACEs [HR 0.89 (95% CI 0.84-0.93)]. Results were confirmed in subgroup analyses, censoring at BB discontinuation or switch, after 1:1 propensity score matching, reclassifying bisoprolol or excluding bisoprolol/carvedilol users.

CONCLUSIONS

This study does not offer support for the hypothesis that the dialyzability of BBs reduces their efficacy in HD patients.

β-blockers in hemodialysis: simple questions, complicated answers

In this issue of the Clinical Kidney Journal, Wu et al. present the results of a nationwide population-based study using Taiwanese administrative data to compare safety and efficacy outcomes with initiation of bisoprolol versus carvedilol among patients receiving maintenance hemodialysis for >90 days. The primary outcomes were all-cause mortality and major adverse cardiovascular events over 2 years of follow-up. The study found that bisoprolol was associated with a lower risk for both major adverse cardiovascular events and all-cause mortality compared with carvedilol. While the bulk of the existing evidence favors a cardioprotective and survival benefit with β-blockers as a medication class among dialysis patients, there is wide heterogeneity among specific β-blockers in regard to pharmacologic properties and dialyzability. While acknowledging the constraints of observational data, these findings may serve to inform clinicians about the preferred β-blocker agent for dialysis patients to help mitigate cardiovascular risk and improve long-term survival for this high-risk population.

Comparative effectiveness of bisoprolol and carvedilol among patients receiving maintenance hemodialysis

Background

Despite widespread use, there is no trial evidence to inform β-blocker's (BB) relative safety and efficacy among patients undergoing hemodialysis (HD). We herein compare health outcomes associated with carvedilol or bisoprolol use, the most commonly prescribed BBs in these patients.

Methods

We created a cohort study of 9305 HD patients who initiated bisoprolol and 11 171 HD patients who initiated carvedilol treatment between 2004 and 2011. We compared the risk of all-cause mortality and major adverse cardiovascular events (MACEs) between carvedilol and bisoprolol users during a 2-year follow-up.

Results

Bisoprolol initiators were younger, had shorter dialysis vintage, were women, had common comorbidities of hypertension and hyperlipidemia and were receiving statins and antiplatelets, but they had less heart failure and digoxin prescriptions than carvedilol initiators. During our observations, 1555 deaths and 5167 MACEs were recorded. In the multivariable-adjusted Cox model, bisoprolol initiation was associated with a lower all-cause mortality {hazard ratio [HR] 0.66 [95% confidence interval (CI) 0.60-0.73]} compared with carvedilol initiation. After accounting for the competing risk of death, bisoprolol use (versus carvedilol) was associated with a lower risk of MACEs [HR 0.85 (95% CI 0.80-0.91)] and attributed to a lower risk of heart failure [HR 0.83 (95% CI 0.77-0.91)] and ischemic stroke [HR 0.84 (95% CI 0.72-0.97)], but not to differences in the risk of acute myocardial infarction [HR 1.03 (95% CI 0.93-1.15)]. Results were confirmed in propensity score matching analyses, stratified analyses and analyses that considered prescribed dosages or censored patients discontinuing or switching BBs.

Conclusions

Relative to carvedilol, bisoprolol initiation by HD patients was associated with a lower 2-year risk of death and MACEs, mainly attributed to lower heart failure and ischemic stroke risk.

β-Blocker Use and Risk of Mortality in Heart Failure Patients Initiating Maintenance Dialysis

RATIONAL & OBJECTIVE

Beta-blockers are recommended for patients with heart failure (HF) but their benefit in the dialysis population is uncertain. Beta-blockers are heterogeneous, including with respect to their removal by hemodialysis. We sought to evaluate whether β-blocker use and their dialyzability characteristics were associated with early mortality among patients with chronic kidney disease with HF who transitioned to dialysis.

STUDY DESIGN

Retrospective cohort study.

SETTING & PARTICIPANTS

Adults patients with chronic kidney disease (aged≥18 years) and HF who initiated either hemodialysis or peritoneal dialysis during January 1, 2007, to June 30, 2016, within an integrated health system were included.

EXPOSURES

Patients were considered treated with β-blockers if they had a quantity of drug dispensed covering the dialysis transition date.

OUTCOMES

All-cause mortality within 6 months and 1 year or hospitalization within 6 months after transition to maintenance dialysis.

ANALYTICAL APPROACH

Inverse probability of treatment weights using propensity scores was used to balance covariates between treatment groups. Cox proportional hazard analysis and logistic regression were used to investigate the association between β-blocker use and study outcomes.

RESULTS

3,503 patients were included in the study. There were 2,115 (60.4%) patients using β-blockers at transition. Compared with nonusers, the HR for all-cause mortality within 6 months was 0.79 (95% CI, 0.65-0.94) among users of any β-blocker and 0.68 (95% CI, 0.53-0.88) among users of metoprolol at transition. There were no observed differences in all-cause or cardiovascular-related hospitalization.

LIMITATIONS

The observational nature of our study could not fully account for residual confounding.

CONCLUSIONS

Beta-blockers were associated with a lower rate of mortality among incident hemodialysis patients with HF. Similar associations were not observed for hospitalizations within the first 6 months following transition to dialysis.

Coronary artery disease in dialysis patients: evidence synthesis, controversies and proposed management strategies

Cardiovascular disease (CVD) remains the leading cause of morbidity and mortality among patients with end-stage renal disease (ESRD). Clustering of traditional atherosclerotic and non-traditional risk factors drive the excess rates of coronary and non-coronary CVD in this population. The incidence, severity and mortality of coronary artery disease (CAD) as well as the number of complications of its therapy is higher in dialysis patients than in non-chronic kidney disease patients. Given the lack of randomized clinical trial evidence in this population, current practice is informed by observational data with a significant potential for bias. Furthermore, guidelines lack any recommendation for these patients or extrapolate them from trials performed in non-dialysis patients. Patients with ESRD are more likely to be asymptomatic, posing a challenge to the correct identification of CAD, which is essential for appropriate risk stratification and management. This may lead to "therapeutic nihilism", which has been associated with worse outcomes. Here, the ERA-EDTA EUDIAL Working Group reviews the diagnostic work-up and therapy of chronic coronary syndromes, unstable angina/non-ST elevation and ST-elevation myocardial infarction in dialysis patients, outlining unclear issues and controversies, discussing recent evidence, and proposing management strategies. Indications of antiplatelet and anticoagulant therapies, percutaneous coronary intervention and coronary artery bypass grafting are discussed. The issue of the interaction between dialysis session and myocardial damage is also addressed.

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.

Thinking Volume First: Developing a Multifaceted Systematic Approach to Volume Management in Hemodialysis

Purpose of review:

Volume overload and hypovolemia-induced symptoms are common in the hemodialysis (HD) population and frequently result in emergency department visits and hospitalization. A structured strategy for the reporting, evaluation, and management of disordered volume status may improve clinical outcomes and the patient experience. We developed a new strategy that systematically addresses volume issues by leveraging the electronic medical record, technological adjuncts, and multidisciplinary expertise to institute new processes of care in our HD unit.

Sources of information:

This initiative was implemented in a unit located in an urban academic hospital where 250 patients receive maintenance HD. This initiative involved a multidisciplinary team of health professionals including physicians, nurse practitioners, social workers, and dieticians.

Methods:

We generated volume metrics for HD recipients based on routinely collected data from the unit’s electronic medical record. We then engaged stakeholders in a root cause analysis to identify the major causes of abnormal volume metrics locally. We subsequently developed interventions that were designed to address each of the major causes in a pragmatic and sustainable program.

Key findings:

The final product was a local volume management program with 3 components. First, we integrated volume metric reporting into the routine surveillance bloodwork reports across our unit. This enabled the clinical teams to more easily target patients at risk for volume-related adverse events and provide them with closer surveillance. Those identified with abnormal volume metrics were then evaluated with the use of technologic adjuncts such as lung ultrasound and bioimpedance spectroscopy to complement traditional assessments of volume status. Finally, those with abnormal volume metrics underwent rigorous interdisciplinary review for potential nutritional/social interventions.

Limitations:

While we report the successful initial implementation of the program within a single center, it remains unclear whether this initiative will lead to meaningful benefits for HD recipients, be readily applicable in other centers, or be sustainable in the long term.

Implications:

This volume management program will need further evaluation linked to outcome assessment and feasibility in other centers before wider adoption is advocated.

Timing of blood pressure medications and intradialytic hypotension

Intradialytic hypotension (IDH) is a prevalent yet serious complication of hemodialysis, associated with decreased quality of life, inadequate dialysis, vascular access thrombosis, global hypoperfusion, and increased cardiovascular and all-cause mortality. Current guidelines recommend antihypertensive medications be given at night and held the morning of dialysis for affected patients. Despite little evidence to support this recommendation, more than half of patients on dialysis may employ some form of this method. In this article, we will review the available evidence and clinical considerations regarding timing of blood pressure medications and occurrence of IDH, and conclude that witholding BP medications before hemodialysis should not be a routine practice.

Beta-blockers use from the general to the hemodialysis population

Beta-blockers have numerous indications in the general population and are strongly recommended in heart failure, post-myocardial infarction and arrhythmias. In hemodialysis patients, their use is based on weak evidence because of the lack of a sufficient number of randomized clinical trials. The strongest evidence is based on two trials. The first showed better survival with carvedilol in hemodialysis patients with four sessions per week and systolic heart failure. The second found reduced cardiovascular morbidity with atenolol compared to lisinopril in mostly black hypertensive hemodialysis patients. No clinical trials exist regarding myocardial infarction. Large retrospective studies have assessed the benefits of beta-blockers in hemodialysis. A large cohort of hemodialysis patients with new-onset heart failure showed better survival when treated with carvedilol, bisoprolol or metoprolol. Another recent one of 20,064 patients found out that metoprolol compared to carvedilol was associated with less all-cause mortality. There is still uncertainty also regarding the impact of dialysability of beta-blockers on patient's survival. On top of that, many observations suggested that beta-blockers were associated with a reduced rate of sudden cardiac death in hemodialysis patients but recent data show a link between bradycardia and sudden cardiac death questioning the benefit of beta-blockade in this population. Finally, what we know for sure so far is that beta-blockers should be avoided in patients with intradialytic hypotension associated with bradycardia.

Sympathetic overactivity in dialysis patients-Underappreciated and clinically consequential

Cardiovascular morbidity and mortality remain frustratingly common in dialysis patients. A dearth of established evidence-based treatment calls for alternative therapeutic avenues to be embraced. Sympathetic hyperactivity, predominantly due to afferent nerve signaling from the diseased native kidneys, has been established to be prognostic in the dialysis population for over 15 years. Despite this, tangible therapeutic interventions have, to date, been unsuccessful and the outlook for patients remains poor. This narrative review summarizes established experimental and clinical data, highlighting recent developments, and proposes why interventions to ameliorate sympathetic hyperactivity may well be beneficial for this high-risk population.