The β-Blocker to Lower Cardiovascular Dialysis Events (BLOCADE) Feasibility Study: A Randomized Controlled Trial

Antihypertensive Drug Treatment and the Risk for Intrahemodialysis Hypotension

Key Points

Antihypertensive medications are often used by hemodialysis patients, and intradialytic hypotension is a common complication in these patients. The study emulates a randomized clinical trial comparing antihypertensive drug treatment for the risk of hemodialysis hypotension in 4072 incident patients. Compared with calcium antagonists, β and α –β blockers, angiotensin converting enzyme inhibitors or angiotensin II antagonists, and diuretics may increase the risk of hemodialysis hypotension.

Background

Antihypertensive medications are often prescribed to manage hypertension in hemodialysis patients, and intradialytic hypotension (IDH) is a common complication in these patients. We investigated the risk of IDH in incident hemodialysis patients who initiated treatment with antihypertensive drugs in monotherapy.

Methods

The study was conducted as an emulation of a randomized clinical trial in 4072 incident hemodialysis patients who started antihypertensive drug treatment between January 2016 and December 2019. The primary outcome was the occurrence of IDH during hemodialysis sessions. The generalized estimating equation analysis was adjusted by inverse probability treatment weighting.

Results

Calcium channel blocker (CCB) use was associated with an IDH incidence rate of 7.4 events per person-year (95% confidence interval [CI], 6.2 to 8.6). Compared with CCB use, use of β and α –β blockers was strongly associated with a higher likelihood of IDH (odds ratio [OR] [95% CI, 2.27; 1.50 to 3.43]). The use of angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers (OR [95% CI, 1.71; 1.14 to 2.57]) and diuretics (OR [95% CI, 1.52; 1.07 to 2.16]) were also associated with a higher likelihood of IDH compared with CCB use.

Conclusions

The study suggests that using β and α –β blockers, angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers, and diuretics may increase the risk of IDH in hemodialysis patients compared with CCB use.

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.

The Possible Effect of β-Blocker Use on the Circulating MMP-2/TIMP-2 System in Patients with Chronic Kidney Disease on Conservative Treatment

Background: The purpose of the study was to determine whether the use of β-adrenoceptor antagonists (β-blockers) can affect metalloproteinase 2 (MMP-2) and its tissue inhibitor (TIMP-2) in patients with chronic kidney disease (CKD) on conservative treatment. Methods: The circulating MMP-2/TIMP-2 system, proinflammatory cytokines (tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6), and the marker of oxidative stress-Cu/Zn superoxide dismutase (Cu/Zn SOD)-were measured in 23 CKD patients treated with β-blockers [β-blockers (+)] and in 27 CKD patients not receiving the above medication [β-blockers (-)]. Results: The levels of MMP-2, TIMP-2, and IL-6 were significantly lower in the β-blockers (+) than in the β-blockers (-) group, whereas Cu/Zn SOD concentrations were not affected by β-blocker use. There was a strong, independent association between MMP-2 and TIMP-2 in both analyzed patient groups. In the β-blockers (+) group, MMP-2 levels were indirectly related to the signs of inflammation, whereas in the β-blockers (-) group, the alterations in the MMP-2/TIMP-2 system were associated with the oxidative stress marker and CKD etiology. Conclusions: This study is the first to suggest that the use of β-blockers was associated with the reduction in IL-6 and the MMP-2/TIMP-2 system in CKD, providing a pharmacological rationale for the use of β-blockers to reduce inflammation and abnormal vascular remodeling in CKD.

Association between beta-blocker utilization and heart failure mortality in the peritoneal dialysis population: a cohort study

Background

The prognostic significance of beta(β)-blocker therapy in patients at end-stage renal disease, specifically those receiving peritoneal dialysis (PD) and presenting with heart failure, remains inadequately elucidated due to limited research conducted thus far.

Methods

A retrospective analysis was performed on a cohort comprising 608 patients receiving PD between September 2007 and March 2019, with a subsequent follow-up period extending until December 2020. Cox regression and propensity score matching weighted analysis was used to model adjusted hazard ratios for β-blocker use with heart failure-related mortality. Competing risk analysis and subgroup analysis were carried out to further elucidate the correlation.

Results

β-blockers were prescribed for 56.1% of the peritoneal dialysis patients. Heart failure occurred in 43.4% of the total population and 15.5% of deaths were due to heart failure. The prescription of β-blockers was associated with a 43% lower adjusted hazard ratio (HR) for heart failure death within the cohort (95% confidence interval [CI] = 0.36-0.89; P = 0.013). Even after accounting for competing risk events, patients in the group using β-blockers demonstrated a significantly lower cumulative risk of heart failure-related mortality compared to those not using β-blockers (P = 0.007). This protective effect of β-blockers was also observed in subgroup analyses. Conversely, β-blocker use had no statistically significant associations with all-cause mortality.

Conclusion

The use of β-blockers was associated with a reduced risk of heart failure-related mortality in the PD population. Future randomized clinical trials are warranted to confirm the beneficial effect of β-blockers in the context of PD.

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.

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.

Valvular heart disease and calcification in CKD: more common than appreciated

Ischaemic heart disease, sudden cardiac death and arrhythmias, heart failure, stroke and peripheral arterial disease make up >50% of the causes of death in advanced chronic kidney disease (CKD). Calcification of the vascular tree and heart valves is partially related to these complications and has received growing attention in the literature. However, the main focus of research has been on the pathophysiology and consequences of vascular calcification, with less attention being paid to valvular calcification (VC) and its impact on the survival of CKD patients. Although VC has long been seen as an age-related degenerative disorder with minimal functional impact, several studies proved that it carries an increased risk of death and clinical consequences different from those of vascular calcification. In dialysis patients, the annual incidence of aortic valve calcification is nearly 3.3% and the reported prevalence of aortic and mitral VC varies between 25% and 59%. Moreover, calcification of both valves occurs 10-20 years earlier in CKD patients compared with the general population. Therefore, the purpose of this review is to summarize the current knowledge on the pathophysiology and relevance of VC in CKD patients, and to highlight specific clinical consequences and potential therapeutic implications.

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.

Better peridialytic blood pressure control using carvedilol in end stage renal disease patients on twice weekly maintenance hemodialysis

BACKGROUND

While use of carvedilol in patients on hemodialysis is encouraged with its low dialyzability, evidence supporting its superiority over metoprolol in improving the blood pressure control during dialysis is lacking. This study was undertaken to study the blood pressure variations in the peridialytic period after conversion from metoprolol to carvedilol.

MATERIALS AND METHODS

In this this prospective, pre-post intervention study, patients on metoprolol were converted to carvedilol. Patients aged 18-65 years on biweekly dialysis with intradialytic rise in blood pressure {difference between pre- and post-dialysis systolic blood pressure > 10 mmHg with post-dialysis blood pressure of ≥ 130/80 mmHg} were recruited. The recorded blood pressure data post conversion to carvedilol was compared to the retrospective mean blood pressure recordings during metoprolol use.

RESULTS

Of the 48 subjects, the study mostly comprised young males (n-34, mean age- 37.06 ± 14.32 years). Both systolic and diastolic blood pressures at different time periods (pre-dialysis, intradialytic and post-dialysis) were significantly lower with carvedilol use than with metoprolol, p < 0.001. Mean pre-dialysis systolic blood pressures and diastolic blood pressures were 140.54 ± 7.68 and 84.42 ± 7.78 mmHg on carvedilol as compared to 148.12 ± 7.17 and 91.17 ± 6.97 mmHg on metoprolol (p < 0.001). Post-dialysis systolic blood pressures and diastolic blood pressures during Carvedilol regimen were better controlled at 147.42 ± 12.89 and 86.29 ± 7.31 mmHg, than 159.12 ± 8.18 and 97 ± 6.76 mmHg during metoprolol regimen (p < 0.001).

CONCLUSION

Our study has brought into focus the younger population at risk of peridialytic hypertension. Switch from metoprolol to carvedilol is an effective anti-hypertensive strategy in dialysis patients with poorly controlled peridialytic blood pressures. Carvedilol was well tolerated.

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 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.

Pharmacological interventions for heart failure in people with chronic kidney disease

BACKGROUND

Approximately half of people with heart failure have chronic kidney disease (CKD). Pharmacological interventions for heart failure in people with CKD have the potential to reduce death (any cause) or hospitalisations for decompensated heart failure. However, these interventions are of uncertain benefit and may increase the risk of harm, such as hypotension and electrolyte abnormalities, in those with CKD.

OBJECTIVES

This review aims to look at the benefits and harms of pharmacological interventions for HF (i.e., antihypertensive agents, inotropes, and agents that may improve the heart performance indirectly) in people with HF and CKD.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Register of Studies through 12 September 2019 in consultation with an Information Specialist and 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 randomised controlled trials of any pharmacological intervention for acute or chronic heart failure, among people of any age with chronic kidney disease of at least three months duration.

DATA COLLECTION AND ANALYSIS

Two authors independently screened the records to identify eligible studies and extracted data on the following dichotomous outcomes: death, hospitalisations, worsening heart failure, worsening kidney function, hyperkalaemia, and hypotension. We used random effects meta-analysis to estimate treatment effects, which we expressed as a risk ratio (RR) with 95% confidence intervals (CI). We assessed the risk of bias using the Cochrane tool. We applied the GRADE methodology to rate the certainty of evidence.

MAIN RESULTS

One hundred and twelve studies met our selection criteria: 15 were studies of adults with CKD; 16 studies were conducted in the general population but provided subgroup data for people with CKD; and 81 studies included individuals with CKD, however, data for this subgroup were not provided. The risk of bias in all 112 studies was frequently high or unclear. Of the 31 studies (23,762 participants) with data on CKD patients, follow-up ranged from three months to five years, and study size ranged from 16 to 2916 participants. In total, 26 studies (19,612 participants) reported disaggregated and extractable data on at least one outcome of interest for our review and were included in our meta-analyses. In acute heart failure, the effects of adenosine A1-receptor antagonists, dopamine, nesiritide, or serelaxin on death, hospitalisations, worsening heart failure or kidney function, hyperkalaemia, hypotension or quality of life were uncertain due to sparse data or were not reported. In chronic heart failure, the effects of angiotensin-converting enzyme inhibitors (ACEi) or angiotensin receptor blockers (ARB) (4 studies, 5003 participants: RR 0.85, 95% CI 0.70 to 1.02; I2 = 78%; low certainty evidence), aldosterone antagonists (2 studies, 34 participants: RR 0.61 95% CI 0.06 to 6.59; very low certainty evidence), and vasopressin receptor antagonists (RR 1.26, 95% CI 0.55 to 2.89; 2 studies, 1840 participants; low certainty evidence) on death (any cause) were uncertain. Treatment with beta-blockers may reduce the risk of death (any cause) (4 studies, 3136 participants: RR 0.69, 95% CI 0.60 to 0.79; I2 = 0%; moderate certainty evidence). Treatment with ACEi or ARB (2 studies, 1368 participants: RR 0.90, 95% CI 0.43 to 1.90; I2 = 97%; very low certainty evidence) had uncertain effects on hospitalisation for heart failure, as treatment estimates were consistent with either benefit or harm. Treatment with beta-blockers may decrease hospitalisation for heart failure (3 studies, 2287 participants: RR 0.67, 95% CI 0.43 to 1.05; I2 = 87%; low certainty evidence). Aldosterone antagonists may increase the risk of hyperkalaemia compared to placebo or no treatment (3 studies, 826 participants: RR 2.91, 95% CI 2.03 to 4.17; I2 = 0%; low certainty evidence). Renin inhibitors had uncertain risks of hyperkalaemia (2 studies, 142 participants: RR 0.86, 95% CI 0.49 to 1.49; I2 = 0%; very low certainty). We were unable to estimate whether treatment with sinus node inhibitors affects the risk of hyperkalaemia, as there were few studies and meta-analysis was not possible. Hyperkalaemia was not reported for the CKD subgroup in studies investigating other therapies. The effects of ACEi or ARB, or aldosterone antagonists on worsening heart failure or kidney function, hypotension, or quality of life were uncertain due to sparse data or were not reported. Effects of anti-arrhythmic agents, digoxin, phosphodiesterase inhibitors, renin inhibitors, sinus node inhibitors, vasodilators, and vasopressin receptor antagonists were very uncertain due to the paucity of studies.

AUTHORS' CONCLUSIONS

The effects of pharmacological interventions for heart failure in people with CKD are uncertain and there is insufficient evidence to inform clinical practice. Study data for treatment outcomes in patients with heart failure and CKD are sparse despite the potential impact of kidney impairment on the benefits and harms of treatment. Future research aimed at analysing existing data in general population HF studies to explore the effect in subgroups of patients with CKD, considering stage of disease, may yield valuable insights for the management of people with HF and CKD.

Techniques to improve intradialytic haemodynamic stability

PURPOSE OF REVIEW

Intra-dialytic hypotension (IDH) remains a significant problem for patients undergoing chronic haemodialysis. IDH causes symptoms that degrade patients' experience, compromises dialysis delivery and is strongly associated with adverse patient outcomes. Greater understanding of the link between IDH and dialysis-induced ischaemia in heart and brain has characterized mechanistic pathways, with repeated episodes of ischaemia resulting in organ dysfunction. This review provides updates from published evidence over the last 2 years across the range of potential interventions for IDH.

RECENT FINDINGS

A literature search was undertaken to identify articles published in peer review journals between January 2016 and April 2018 using terms 'intradialytic hypotension,' 'haemodynamic instability,' 'ESRF,' 'renal replacement therapy,' 'dialysis' in Medline and EMBASE and identified 58 references from which 15 articles were included in this review. Interventions included: cooling the dialysate; sodium profiling; convective therapies; strategies to minimize inter-dialytic weight gain (IDWG) and improve accuracy of target weight assessment; prescribing of antihypertensive medications; and carnitine supplementation.

SUMMARY

IDH remains a significant clinical problem. Recent evidence from the last 2 years does not support any major changes to current practice, with cooling of the dialysate and reduction of IDWG remaining cornerstones of management.

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.

Blood pressure control in conventional hemodialysis

Hypertension among patients on hemodialysis is common, difficult to diagnose and often inadequately controlled. Although specific blood pressure (BP) targets in this particular population are not yet established, meta-analyses of randomized trials showed that deliberate BP-lowering with antihypertensive drugs improves clinical outcomes in hemodialysis patients. BP-lowering in these individuals should initially utilize nonpharmacological strategies aiming to control sodium and volume overload. Accordingly, restricting dietary sodium intake, eliminating intradialytic sodium gain via individualized dialysate sodium prescription, optimally assessing and managing dry-weight and providing a sufficient duration of dialysis are first-line treatment considerations to control BP. If BP remains uncontrolled despite the adequate management of volume, antihypertensive therapy is the next consideration. Contrary to nonhemodialysis populations, emerging clinical-trial evidence suggests that among those on hemodialysis, β-blockers are more effective than agents blocking the renin-angiotensin-system (RAS) in reducing BP levels and protecting from serious adverse cardiovascular complications. Accordingly, β-blockade is our first-line approach in pharmacotherapy of hypertension. Long-acting calcium-channel-blockers and RAS-blockers are our next considerations, taking into account the comorbidities and the overall risk profile of each individual patient. Additional research efforts, mainly randomized trials, are clearly warranted in order to elucidate aspects of management that remain elusive in hypertensive dialysis patients.

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

BACKGROUND

Carvedilol and metoprolol are the β-blockers most commonly prescribed to US hemodialysis patients, accounting for ∼80% of β-blocker prescriptions. Despite well-established pharmacologic and pharmacokinetic differences between the 2 medications, little is known about their relative safety and efficacy in the hemodialysis population.

STUDY DESIGN

A retrospective cohort study using a new-user design.

SETTING & PARTICIPANTS

Medicare-enrolled hemodialysis patients treated at a large US dialysis organization who initiated carvedilol or metoprolol therapy from January 1, 2007, through December 30, 2012.

PREDICTOR

Carvedilol versus metoprolol initiation.

OUTCOMES

All-cause mortality, cardiovascular mortality, and intradialytic hypotension (systolic blood pressure decrease ≥ 20mmHg during hemodialysis plus intradialytic saline solution administration) during a 1-year follow-up period.

MEASUREMENTS

Survival models were used to estimate HRs and 95% CIs in mortality analyses. Poisson regression was used to estimate incidence rate ratios (IRRs) and 95% CIs in intradialytic hypotension analyses. Inverse probability of treatment weighting was used to adjust for several demographic, clinical, laboratory, and dialysis treatment covariates in all analyses.

RESULTS

27,064 individuals receiving maintenance hemodialysis were included: 9,558 (35.3%) carvedilol initiators and 17,506 (64.7%) metoprolol initiators. Carvedilol (vs metoprolol) initiation was associated with greater all-cause (adjusted HR, 1.08; 95% CI, 1.02-1.16) and cardiovascular mortality (adjusted HR, 1.18; 95% CI, 1.08-1.29). In subgroup analyses, similar associations were observed among patients with hypertension, atrial fibrillation, heart failure, and a recent myocardial infarction, the main cardiovascular indications for β-blocker therapy. During follow-up, carvedilol (vs metoprolol) initiators had a higher rate of intradialytic hypotension (adjusted IRR, 1.10; 95% CI, 1.09-1.11).

LIMITATIONS

Residual confounding may exist.

CONCLUSIONS

Relative to metoprolol initiation, carvedilol initiation was associated with higher 1-year all-cause and cardiovascular mortality. One potential mechanism for these findings may be the increased occurrence of intradialytic hypotension after carvedilol (vs metoprolol) initiation.

Beta blockers in patients with end-stage renal disease-Evidence-based recommendations

For patients who require hemodialysis, beta blockers offer a simultaneous opportunity and challenge in the treatment of cardiovascular disease. Beta blockers are well supported by data from nondialysis populations and directly mitigate the sympathetic overactivity that links chronic kidney disease with cardiovascular sequelae. However, the evidence supporting their use in patients receiving hemodialysis is sparse and the heterogeneity of the beta blocker class makes it difficult to prescribe these medications with confidence. Despite these limitations, both trial and observational data exist that can help guide the use of these medications. In this review, we outline the reasons to consider beta blockers for patients receiving hemodialysis, discuss the barriers to their use, and provide specific evidence-based recommendations for beta blocker use in patients with heart failure, hypertension, ischemic heart disease and arrhythmia.

Patient Engagement in Kidney Research: Opportunities and Challenges Ahead

PURPOSE OF REVIEW

Patient engagement in research is increasingly recognized as an important component of the research process and may facilitate translation of research findings. To heighten awareness on this important topic, this review presents opportunities and challenges of patient engagement in research, drawing on specific examples from 4 areas of Canadian kidney research conducted by New Investigators in the Kidney Research Scientist Core Education and National Training (KRESCENT) Program.

SOURCES OF INFORMATION

Research expertise, published reports, peer-reviewed articles, and research funding body websites.

METHODS

In this review, the definition, purpose, and potential benefits of patient engagement in research are discussed. Approaches toward patient engagement that may help with translation and uptake of research findings into clinical practice are highlighted. Opportunities and challenges of patient engagement are presented in both basic science and clinical research with the following examples of kidney research: (1) precision care in focal and segmental glomerulosclerosis, (2) systems biology approaches to improve management of chronic kidney disease and enhance kidney graft survival, (3) reducing the incidence of suboptimal dialysis initiation, and (4) use of patient-reported outcome measures (PROMs) and patient-reported experience measures (PREMs) in kidney practice.

KEY FINDINGS

Clinical research affords more obvious opportunities for patient engagement. The most obvious step at which to engage patients is in the setting of research priorities. Engagement at all stages of the research cycle may prove to be more challenging, and requires a detailed plan, along with funds and infrastructure to ensure that it is not merely tokenistic. Basic science research is several steps removed from the clinical application and involves complex scientific concepts, which makes patient engagement inherently more difficult.

LIMITATIONS

This is a narrative review of the literature that has been partly influenced by the perspectives and experiences of the authors and focuses on research conducted by the authors. The evidence base to support the suggested benefits of patient engagement in research is currently limited.

IMPLICATIONS

The formal incorporation of patients' priorities, perspectives, and experiences is now recognized as a key component of the research process. If patients and researchers are able to effectively work together, this could enhance research quality and efficiency. To effectively engage patients, proper infrastructure and dedicated funding are needed. Going forward, a rigorous evaluation of patient engagement strategies and their effectiveness will be needed.

Hypertension in dialysis patients: a consensus document by the European Renal and Cardiovascular Medicine (EURECA-m) working group of the European Renal Association - European Dialysis and Transplant Association (ERA-EDTA) and the Hypertension and the Kidney working group of the European Society of Hypertension (ESH)

In patients with end-stage renal disease treated with hemodialysis or peritoneal dialysis, hypertension is very common and often poorly controlled. Blood pressure (BP) recordings obtained before or after hemodialysis display a J-shaped or U-shaped association with cardiovascular events and survival, but this most likely reflects the low accuracy of these measurements and the peculiar hemodynamic setting related with dialysis treatment. Elevated BP by home or ambulatory BP monitoring is clearly associated with shorter survival. Sodium and volume excess is the prominent mechanism of hypertension in dialysis patients, but other pathways, such as arterial stiffness, activation of the renin-angiotensin-aldosterone and sympathetic nervous systems, endothelial dysfunction, sleep apnea and the use of erythropoietin-stimulating agents may also be involved. Nonpharmacologic interventions targeting sodium and volume excess are fundamental for hypertension control in this population. If BP remains elevated after appropriate treatment of sodium-volume excess, the use of antihypertensive agents is necessary. Drug treatment in the dialysis population should take into consideration the patient's comorbidities and specific characteristics of each agent, such as dialysability. This document is an overview of the diagnosis, epidemiology, pathogenesis and treatment of hypertension in patients on dialysis, aiming to offer the renal physician practical recommendations based on current knowledge and expert opinion and to highlight areas for future research.

Impact of drugs on intradialytic hypotension: Antihypertensives and vasoconstrictors

Intradialytic hypotension (IDH) is a common complication of hemodialysis and is associated with numerous adverse outcomes including cardiovascular events, inadequate dialysis, loss of vascular access, and death. It is estimated that approximately 20%-30% of all dialysis sessions are affected by IDH. In seeking ways to reduce the occurrence of IDH, dialysis providers often turn to pharmacological approaches: withholding antihypertensive medications prior to hemodialysis or administering vasoconstrictor medications. This review will focus on what is known about the relation between antihypertensive medications and IDH, and summarize studies that have examined the efficacy of vasoconstrictor medications on IDH, including midodrine, arginine vasopressin, and droxidopa. However, there is currently scant evidence that any pharmacological approach is particularly effective in reducing IDH. Additional studies of potential treatments for IDH are needed, and should examine not only hemodynamic effects such as changes in nadir blood pressure during dialysis, but also on patient-centered and clinical outcomes such as symptoms of IDH, quality of life, and cardiovascular events.

Hypertension in dialysis patients: a consensus document by the European Renal and Cardiovascular Medicine (EURECA-m) working group of the European Renal Association-European Dialysis and Transplant Association (ERA-EDTA) and the Hypertension and the Kidney working group of the European Society of Hypertension (ESH)

In patients with end-stage renal disease (ESRD) treated with haemodialysis or peritoneal dialysis, hypertension is common and often poorly controlled. Blood pressure (BP) recordings obtained before or after haemodialysis display a J- or U-shaped association with cardiovascular events and survival, but this most likely reflects the low accuracy of these measurements and the peculiar haemodynamic setting related to dialysis treatment. Elevated BP detected by home or ambulatory BP monitoring is clearly associated with shorter survival. Sodium and volume excess is the prominent mechanism of hypertension in dialysis patients, but other pathways, such as arterial stiffness, activation of the renin-angiotensin-aldosterone and sympathetic nervous systems, endothelial dysfunction, sleep apnoea and the use of erythropoietin-stimulating agents may also be involved. Non-pharmacologic interventions targeting sodium and volume excess are fundamental for hypertension control in this population. If BP remains elevated after appropriate treatment of sodium and volume excess, the use of antihypertensive agents is necessary. Drug treatment in the dialysis population should take into consideration the patient's comorbidities and specific characteristics of each agent, such as dialysability. This document is an overview of the diagnosis, epidemiology, pathogenesis and treatment of hypertension in patients on dialysis, aiming to offer the renal physician practical recommendations based on current knowledge and expert opinion and to highlight areas for future research.

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.

Epidemiology, diagnosis and management of hypertension among patients on chronic dialysis

The diagnosis and management of hypertension among patients on chronic dialysis is challenging. Routine peridialytic blood pressure recordings are unable to accurately diagnose hypertension and stratify cardiovascular risk. By contrast, blood pressure recordings taken outside the dialysis setting exhibit clear prognostic associations with survival and might facilitate the diagnosis and long-term management of hypertension. Once accurately diagnosed, management of hypertension in individuals on chronic dialysis should initially involve non-pharmacological strategies to control volume overload. Accordingly, first-line strategies should focus on achieving dry weight, individualizing dialysate sodium concentrations and ensuring dialysis sessions are at least 4 h in duration. If blood pressure remains unresponsive to volume management strategies, pharmacological treatment is required. The choice of appropriate antihypertensive regimen should be individualized taking into account the efficacy, safety, and pharmacokinetic properties of the antihypertensive medications as well as any comorbid conditions and the overall risk profile of the patient. In contrast to their effects in the general hypertensive population, emerging evidence suggests that β-blockers might offer the greatest cardioprotection in hypertensive patients on dialysis. In this Review, we discuss estimates of the epidemiology of hypertension in the dialysis population as well as the challenges in diagnosing and managing hypertension among these patients.