Management of Hyperkalemia in Renin-Angiotensin-Aldosterone System Inhibitor: Strategies to Maintain Chronic Kidney Disease Patients with Type II Diabetes on Therapy

BACKGROUND

According to the Centers for Disease Control and Prevention (CDC), diabetes affects approximately 37.3 million individuals in the USA, with another estimated 96 million people having a prediabetic state. Furthermore, one or two out of three adult Americans exhibit metabolic syndrome or an insulin-resistant state, depending on their age group.

SUMMARY

Chronic kidney disease (CKD) represents a complication often associated with type II diabetes or the insulin-resistant condition, typically identifiable through proteinuria. Proteinuria serves as both a marker and a contributing factor to kidney damage, and it significantly heightens the risk of cardiovascular (CV) events, including atherosclerosis, heart attacks, and strokes. Renin-angiotensin-aldosterone system inhibitors (RAASis) have demonstrated clinical efficacy in lowering blood pressure, reducing proteinuria, and slowing CKD progression. However, hyperkalemia is a common and serious adverse effect associated with using RAASi.

KEY MESSAGES

It is imperative to establish personalized management strategies to enable patients to continue RAASi therapy while effectively addressing hyperkalemia risk. Healthcare professionals must be careful not to inadvertently create a low renal perfusion state, which can reduce distal nephron luminal flow or luminal sodium concentration while using RAASi. Nonsteroidal mineralocorticoid receptor antagonists (nsMRAs), such as finerenone, are demonstrated to delay CKD progression and reduce CV complications, all while mitigating the risk of hyperkalemia. Additionally, maintaining a routine monitoring regimen for serum potassium levels among at-risk patients, making dietary adjustments, and considering the adoption of newer potassium-binding agents hold promise for optimizing RAASi therapy and achieving more effective hyperkalemia management.

Epidemiology and risk factors for hyperkalaemia in heart failure

Patients with heart failure (HF), particularly those with impaired renal function receiving renin-angiotensin-aldosterone system inhibitors (RAASis), are at risk of hyperkalaemia; when hyperkalaemia is severe, this can have serious clinical consequences. The incidence, prevalence, and risk factors for hyperkalaemia reported in randomized trials of RAASis may not reflect clinical practice due to exclusion of patients with elevated serum potassium (sK+ ) or severe renal impairment: information on patients managed in routine clinical care is important to understanding the actual burden of hyperkalaemia. This paper reviews the available clinical epidemiology data on hyperkalaemia in HF and considers areas requiring further research. Observational studies published since 2017 that focused on hyperkalaemia, included patients with HF, and had ≥1000 participants were considered. Hyperkalaemia occurrence in HF varied widely from 7% to 39% depending on the setting, HF severity, follow-up length, and concomitant medications. Rates were lowest in patients with newly diagnosed HF and highest in patients with greater disease severity; comorbidities, such as chronic kidney disease and diabetes, and RAASi use, reflected commonly identified risk factors for hyperkalaemia in patients with HF. Hyperkalaemia was most often mild; however, from the limited data available, persistence of mild hyperkalaemia was associated with an increased risk of mortality and major adverse cardiovascular events. There were also limited data available on the progression of hyperkalaemia. Recurrence was common, occurring in one-quarter to two-fifths of hyperkalaemia cases. Despite HF guidelines recommending close monitoring of sK+ , 55-93% of patients did not receive appropriate testing before or after initiation of RAASi or in follow-up to moderate/severe hyperkalaemia detection. Many of the observational studies were retrospective and from a single country. There is a need for international, prospective, longitudinal, observational studies, such as the CARE-HK in HF study (NCT04864795), to understand hyperkalaemia's prevalence, incidence, and severity; to identify and characterize cases that persist, progress, and recur; to highlight the importance of sK+ monitoring when using RAASi; and to assess the impact of newer HF therapies and potassium binders in clinical practice. Data from both clinical trials and observational studies with adjustments for confounding variables will be needed to assess the contribution of hyperkalaemia to clinical outcomes.

Maintaining Renin-Angiotensin-Aldosterone System Inhibitor Treatment with Patiromer in Hyperkalaemic Chronic Kidney Disease Patients: Comparison of a Propensity-Matched Real-World Population with AMETHYST-DN

INTRODUCTION

Guideline-directed renin-angiotensin-aldosterone system inhibitor (RAASi) therapy is rarely achieved in clinical settings, often due to hyperkalaemia. We assessed the potassium binder, patiromer, on continuation of RAASi therapy in hyperkalaemic patients with chronic kidney disease (CKD) and type 2 diabetes mellitus (T2DM) in the AMETHYST-DN trial, propensity score-matched to a real-world cohort not receiving patiromer (Salford Kidney Study).

METHODS

The phase 2, open-label AMETHYST-DN trial (NCT01371747) randomized 304 adults with CKD on RAASi, T2DM, hyperkalaemia (serum potassium [sK+] >5.0 mEq/L), and hypertension to receive patiromer, 8.4-33.6 g/day for 12 months. Patients underwent propensity score matching for systolic blood pressure (BP), heart failure status, and estimated glomerular filtration rate (eGFR), with 321 patients with CKD, T2DM, hyperkalaemia, and on RAASi from a prospective CKD cohort (Salford Kidney Study). Changes in RAASi utilization, sK+, BP, proteinuria, and eGFR during 12-month follow-up were assessed by Mann-Whitney U or χ2 tests.

RESULTS

Matching produced 135:135 patients with no significant differences in age, sex, systolic BP, sK+, eGFR, or heart failure status, although differences in diastolic BP remained (p < 0.001). After 12 months, 100% of AMETHYST-DN patients receiving patiromer remained on RAASi therapy, whereas 38.5% of the Salford Kidney Cohort discontinued RAASi (p < 0.001); hyperkalaemia contributed in 16% of patients (42% of RAASi discontinuations). Significantly greater reductions in sK+ and BP, but not proteinuria or eGFR, were observed in AMETHYST-DN, compared with Salford Kidney Study patients (p < 0.05).

CONCLUSIONS

These results demonstrate the benefit of patiromer for sK+ management to enable RAASi use while revealing beneficial effects on BP.

Real-World Modifications of Renin-Angiotensin-Aldosterone System Inhibitors in Patients with Hyperkalemia Initiating Sodium Zirconium Cyclosilicate Therapy: The OPTIMIZE I Study

INTRODUCTION

Hyperkalemia (HK) may result in disruptions of guidelines-concordant renin-angiotensin-aldosterone system inhibitors (RAASi), a standard of care in persons with chronic kidney disease (CKD). Such disruptions-dose reduction or discontinuation-diminish the benefits of RAASi, placing patients at risk of serious events and renal dysfunction. This real-world study evaluated RAASi modifications among patients who initiated sodium zirconium cyclosilicate (SZC) for HK.

METHODS

Adults (≥ 18 years) initiating outpatient SZC (index date) while on RAASi were identified from a large US claims database (January 2018-June 2020). RAASi optimization (maintain same or up-titration of RAASi dosage), non-optimization (down-titration of RAASi dosage or discontinuation), and persistence were descriptively summarized following index. Predictors of RAASi optimization were assessed using multivariable logistic regression models. Analyses were conducted by subgroups, including patients without end-stage kidney disease (ESKD), with CKD, and with CKD + diabetes.

RESULTS

A total of 589 patients initiated SZC during RAASi therapy (mean age 61.0 years, 65.2% male), and 82.7% patients (n = 487) kept RAASi after index (mean follow-up  = 8.1 months). Most patients (77.4%) optimized RAASi therapy after initiating SZC; 69.6% maintained the same dosage while 7.8% had up-titrations. A similar rate of RAASi optimization was observed among subgroups without ESKD (78.4%), with CKD (78.9%), and with CKD + diabetes (78.1%). At 1-year post-index, 73.9% of all patients who optimized RAASi were still on therapy, while only 17.9% of patients who did not optimize therapy were still on a RAASi. Among all patients, predictors of RAASi optimization included fewer prior hospitalizations (odds ratio = 0.79, 95% CI [0.63-1.00]; p < 0.05) and fewer prior emergency department (ED) visits (0.78 [0.63-0.96]; p < 0.05).

CONCLUSION

Consistent with clinical trial findings, nearly 80% of patients who initiated SZC for HK optimized their RAASi therapy. Patients may require long-term SZC therapy to encourage continuation of RAASi therapy especially after inpatient and ED visits.

Serum potassium level and mineralocorticoid receptor antagonist dose in a large cohort of chronic heart failure patients

AIMS

Hyperkalaemia is observed frequently in heart failure (HF) patients and is associated with an impaired prognosis and underuse of mineralocorticoid receptor antagonists (MRAs). However, the effects of serum potassium on prescription of the full guideline recommended daily dose of 50 mg in real-world daily practice are unknown. Therefore, we investigated serum potassium and its association with the prescribed MRA dose in a large cohort of chronic HF patients.

METHODS AND RESULTS

A total of 5346 patients with chronic HF with a left ventricular ejection fraction ≤40% from 34 Dutch outpatient HF clinics between 2013 and 2016 were analysed on serum potassium and MRA (spironolactone and eplenerone) dose. Data were stratified by potassium as a serum potassium level <4.0, 4.0 to 5.0 or >5.0 mmol/L. Multivariable logistic regression models were used to assess the association between serum potassium and MRA dose and to adjust for potential confounders. Mean serum potassium was 4.4 ± 0.5 mmol/L and hyperkalaemia (serum potassium >5.0 mmol/L) was present in 399 patients (7.5%). MRA was used in 3091 patients (58.1%). Patients with hyperkalaemia significantly less often received ≥100% of the target dose (50 mg) compared with patients with a serum potassium between 4.0-5.0 mmol/L and <4.0 mmol/L (7.7% vs. 9.5% vs. 13.6% respectively, P = 0.0078). In the multivariable regression analyses, patients with hyperkalaemia were significantly less likely to receive ≥100% of the target dose compared with patients with serum potassium 4.0-5.0 mmol/L (OR 0.38, 95% CI 0.15-0.97, P = 0.044). Additionally, a one unit increase in serum potassium was significantly associated with a lower odds of receiving ≥100% of the target dose (OR 0.69, 95% CI 0.49-0.98, P = 0.036).

CONCLUSIONS

In this large registry of real-world chronic HF patients, both an increase in serum potassium and hyperkalaemia were associated with a lower odds of receiving the guideline-recommended MRA dose.

An international Delphi consensus regarding best practice recommendations for hyperkalaemia across the cardiorenal spectrum

AIMS

Renin-angiotensin-aldosterone system inhibitors (RAASi) are guideline-recommended therapy for individuals with cardiorenal disease. They are associated with increased risk of hyperkalaemia, a common and life-threatening disorder for this population. RAASi-induced hyperkalaemia often leads to dose reduction or discontinuation, reducing cardiorenal protection. Guideline recommendations differ between specialties for the clinical management of hyperkalaemia. Using a modified Delphi method, we developed consensus recommendations for optimal management of hyperkalaemia in adults with cardiorenal disease.

METHODS AND RESULTS

An international steering group of cardiologists and nephrologists developed 39 statements regarding hyperkalaemia care, including risk factors and risk stratification, prevention, correction, and cross-specialty coordination. Consensus was determined by agreement on an online questionnaire administered to cardiorenal specialists across Europe and North America. The threshold for consensus agreement was established a priori by the steering group at 67%. Across November 2021, 520 responses were received from Canada (n = 50), France (n = 50), Germany (n = 54), Italy (n = 58), Spain (n = 57), the UK (n = 49), and the US (n = 202); 268 from cardiologists and 252 from nephrologists. Twenty-nine statements attained very high agreement (≥90%) and 10 attained high agreement (≥67%-&lt;90%), with strong alignment between cardiologists and nephrologists.

CONCLUSION

A high degree of consensus regarding hyperkalaemia evaluation and management exists among healthcare professionals. Based on high levels of agreement, the steering group derived six key recommendations for hyperkalaemia prevention and management in people with cardiorenal disease. Future studies examining the quality of hyperkalaemia care delivery are required.

COVID-19 and RAAS inhibitors: is there a final conclusion?

Coronavirus disease 2019 (COVID-19), the first pandemic caused by a human infecting coronavirus, has drawn global attention from the first time it appeared in Wuhan city of China in late December 2019. Detection of the responsible viral pathogen, named as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) by WHO, and its possible pathogenesis lead to the forming of many hypotheses about the factors that may affect the patients' outcome. One of the SARS-CoV-2 infection concerns was the potential role of angiotensin-converting enzyme (ACE) inhibitors and angiotensin-receptor blockers (ARBs) in COVID-19 patients' morbidity and mortality. Studies demonstrated that because SARS-CoV-2 uses human ACE2 cell receptors as an entry receptor to invade the cells, there might be an association between antihypertensive drugs such as RAAS inhibitors (specifically ACEIs and ARBs) and the COVID-19 disease. Data are scarce and conflicting regarding ACEI or ARB consumption and how it influences disease outcomes, and a single conclusion has not been reached yet. According to the literature review in our article, the most evidentially supported theory about the use of RAAS inhibitors in COVID-19 is that these medications, including ACEI/ARB, are not associated with the increased risk of infection, disease severity, and patient prognosis. However, further studies are needed to support the hypothesis.

Patiromer for the management of hyperkalaemia in patients receiving renin-angiotensin-aldosterone system inhibitors for heart failure: design and rationale of the DIAMOND trial

AIMS

In patients with current or a history of hyperkalaemia, treatment with renin-angiotensin-aldosterone system inhibitors (RAASi) is often compromised. Patiromer, a novel potassium (K⁺ ) binder, may improve serum K⁺ levels and adherence to RAASi.

METHODS

The DIAMOND trial will enroll ∼820 patients with heart failure with reduced ejection fraction (HFrEF; ejection fraction ≤40%). Patients meeting the screening criteria will enter a single-blinded run-in phase where they will be started or continued on a mineralocorticoid receptor antagonist (MRA) titrated to 50 mg/day and other RAASi therapy to ≥50% target dose, and patiromer. Patiromer will be titrated up to a maximum three packs/day (8.4 g/pack) to achieve optimal doses of RAASi without hyperkalaemia. The run-in phase will last up to 12 weeks, following which patients will undergo double-blind randomization in a 1:1 ratio to receive either continued patiromer or placebo (patiromer withdrawal). The primary endpoint is the mean difference in serum K⁺ from randomization between patiromer and placebo arms. Secondary endpoints will include hyperkalaemia events with K⁺ value >5.5 mEq/L, durable enablement of MRA at target dose, investigator-reported adverse events of hyperkalaemia, hyperkalaemia-related clinical endpoints and an overall RAASi use score (using a 0-8-point scale) comprising all-cause death, occurrence of cardiovascular hospitalization or usage of comprehensive heart failure medication.

CONCLUSION

The DIAMOND trial is designed to determine if patiromer can favourably impact K⁺ control in patients with HFrEF with hyperkalaemia or a history of hyperkalaemia leading to RAASi therapy compromise, and in turn improve RAASi use.

Non-immunosuppressive therapies for childhood IgA nephropathy

IgA nephropathy (IgAN) is the most common chronic primary glomerulonephritis in both children and adults, and 20-30% of patients with persistent hematuria/proteinuria progress to kidney failure within 20 years. In Japan, most cases of childhood IgAN are detected by school screening programs during the early onset of the disease when hematuria/proteinuria are asymptomatic and kidney function is normal. Therefore, it is possible to follow the detailed clinical course and appropriate therapeutic interventions from early onset of the disease. Data on non-immunosuppressive therapies for children with IgAN are highly limited. The Japanese Pediatric IgA Nephropathy Treatment Study Group was organized in 1989 to conduct clinical trials and accumulate data on treatments for childhood IgAN. In this review, we focus on non-immunosuppressive therapies, notably with renin-angiotensin-aldosterone system (RAAS) inhibitors for childhood IgAN and related clinical trials conducted primarily in Japan. We also describe the anti-inflammatory and antiproteinuric effects of RAAS inhibitors in IgAN, differences in treatment regimens because of the acute and active pathological features of childhood IgAN, adverse events of RAAS inhibitors, other non-immunosuppressive treatment options, and future directions.

Consensus on the management of hyperkalemia in patients with heart failure: Recommendations from the SEC-SEMI

Use of renin-angiotensin-aldosterone system inhibitors (RAASi) in patients with heart failure (HF) and reduced ejection fraction is associated with functional improvement, an increase in perceived quality of life, a reduction in the probability of cardiovascular death, and a decrease in the number of hospitalizations. Some of these drugs are also efficacious in patients with chronic kidney disease and albuminuria as well as in patients with resistant hypertension. Despite their numerous benefits, RAASi are associated with an increase in incidence of hyperkalemia, especially in patients with concomitant chronic kidney disease. Hyperkalemia is a common electrolyte disorder that is defined as an elevation in plasma concentrations of potassium above 5 mEq/L. It has been related to rehospitalizations, malignant arrhythmias, and an increase in mortality. On the other hand, optimized treatment with RAASi requires progressive dose increases which can in turn entail a greater probability of hyperkalemia. For all of these reasons, it is necessary to establish management and treatment guidelines for these patients. This consensus document arises from this objective. Its recommendations have been developed by a group of ten experts and reviewed by a panel of another ten specialists in the treatment of patients with HF (ten cardiologists and ten internists in total). This document has been endorsed by the Spanish Society of Cardiology (SEC, for its initials in Spanish) and the Spanish Society of Internal Medicine (SEMI, for its initials in Spanish).

The age again in the eye of the COVID-19 storm: evidence-based decision making

BACKGROUND

One hundred fifty million contagions, more than 3 million deaths and little more than 1 year of COVID-19 have changed our lives and our health management systems forever. Ageing is known to be one of the significant determinants for COVID-19 severity. Two main reasons underlie this: immunosenescence and age correlation with main COVID-19 comorbidities such as hypertension or dyslipidaemia. This study has two aims. The first is to obtain cut-off points for laboratory parameters that can help us in clinical decision-making. The second one is to analyse the effect of pandemic lockdown on epidemiological, clinical, and laboratory parameters concerning the severity of the COVID-19. For these purposes, 257 of SARSCoV2 inpatients during pandemic confinement were included in this study. Moreover, 584 case records from a previously analysed series, were compared with the present study data.

RESULTS

Concerning the characteristics of lockdown series, mild cases accounted for 14.4, 54.1% were moderate and 31.5%, severe. There were 32.5% of home contagions, 26.3% community transmissions, 22.5% nursing home contagions, and 8.8% corresponding to frontline worker contagions regarding epidemiological features. Age > 60 and male sex are hereby confirmed as severity determinants. Equally, higher severity was significantly associated with higher IL6, CRP, ferritin, LDH, and leukocyte counts, and a lower percentage of lymphocyte, CD4 and CD8 count. Comparing this cohort with a previous 584-cases series, mild cases were less than those analysed in the first moment of the pandemic and dyslipidaemia became more frequent than before. IL-6, CRP and LDH values above 69 pg/mL, 97 mg/L and 328 U/L respectively, as well as a CD4 T-cell count below 535 cells/μL, were the best cut-offs predicting severity since these parameters offered reliable areas under the curve.

CONCLUSION

Age and sex together with selected laboratory parameters on admission can help us predict COVID-19 severity and, therefore, make clinical and resource management decisions. Demographic features associated with lockdown might affect the homogeneity of the data and the robustness of the results.

[Recurrent hyperkalaemia management and use of renin-angiotensin-aldosterone system inhibitors: Analysis of French data from the PROKALE multinational European study]

INTRODUCTION

Recurrent hyperkalaemia may result in underutilisation of renin-angiotensin-aldosterone system inhibitors. We report an analysis of French data from the PROKALE retrospective study, which assessed the management of recurrent hyperkalaemia in five European countries.

PATIENTS AND METHODS

A retrospective chart review including patients not on dialysis with two or more hyperkalaemia episodes≥5.5 mEq/L documented within a 12-month observation period was performed.

RESULTS

In France, 115 physicians (57 nephrologists et 58 cardiologists) participated in the study and 295 patients were studied in this analysis. Mean age was 68 years; 212 patients (71.9%) had chronic kidney disease, 108 (36.6%) had chronic heart failure and 102 (34.6%) had diabetes mellitus. The mean number of documented hyperkalaemic episodes was 2.3. A total of 90 hospitalizations occurred during the observation period, of which 24 (26.7%) were directly related to a hyperkalaemic episode. At the time of the first documented hyperkalaemic episode, measures used for the management of hyperkalaemia included loop diuretics (144 patients [48.8%]), sodium/calcium polystyrene sulphonate (135 patients [45.8%]), a low-potassium diet (31 patients [10.5%]) and sodium bicarbonate (31 patients [10.5%]). Between the two consecutive hyperkalaemic episodes documented, the proportion of patients on renin-angiotensin-aldosterone system inhibitors treatment decreased from 42.4% to 34.6%.

CONCLUSION

Renin-angiotensin-aldosterone system inhibitors treatment interruptions were observed in the setting of recurrent hyperkalaemic episodes. Recurrent hyperkalaemia is a major cause of hospitalizations. More effective strategies for the prevention of recurrent hyperkalaemia are needed.

Association between renin-angiotensin-aldosterone system inhibitor use and COVID-19 hospitalization and death: a 1.4 million patient nationwide registry analysis

Aims

Renin–angiotensin–aldosterone system inhibitors (RAASi) improve outcomes in cardiorenal disease but concerns have been raised over increased risk of incident hospitalization and death from coronavirus disease 2019 (COVID‐19). We investigated the association between use of angiotensin‐converting enzyme inhibitors (ACEi), angiotensin receptor blockers (ARBs) or mineralocorticoid receptor antagonists (MRAs) and COVID‐19 hospitalization/death in a large nationwide population.

Methods and results

Patients with hypertension, heart failure, diabetes, kidney disease, or ischaemic heart disease registered in the Swedish National Patient Registry until 1 February 2020 were included and followed until 31 May 2020. COVID‐19 cases were defined based on hospitalization/death for COVID‐19. Multivariable logistic and Cox regressions were fitted to investigate the association between ACEi/ARB and MRA and risk of hospitalization/death for COVID‐19 in the overall population, and of all‐cause mortality in COVID‐19 cases. We performed consistency analysis to quantify the impact of potential unmeasured confounding. Of 1 387 746 patients (60% receiving ACEi/ARB and 5.8% MRA), 7146 (0.51%) had incident hospitalization/death from COVID‐19. After adjustment for 45 variables, ACEi/ARB use was associated with a reduced risk of hospitalization/death for COVID‐19 (odds ratio 0.86, 95% confidence interval 0.81–0.91) in the overall population, and with reduced mortality in COVID‐19 cases (hazard ratio 0.89, 95% confidence interval 0.82–0.96). MRA use was not associated with risk of any outcome. Consistency analysis showed that unmeasured confounding would need to be large for there to be harmful signals associated with RAASi use.

Conclusions

In a 1.4 million nationwide cohort, use of RAASi was not associated with increased risk of hospitalization for or death from COVID‐19.

COVID-19 and cardiovascular diseases

Infection by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is responsible for the second pandemic of the XXI century after influenza A in 2009. As of mid-June 2020, more than 4,40,000 fatal cases of SARS-CoV-2-related disease (COVID-19) have occurred worldwide. Besides its prominent expression at the level of the respiratory apparatus, COVID-19 is also characterized by a substantial degree of cardiovascular involvement, both in terms of deterioration of pre-existing conditions, and as the effect of inflammation-facilitated acute events. They include ischemic/inflammatory heart disease, ventricular arrhythmias, conduction disturbances, thrombotic events at the level of the lungs, and systemic activation of the coagulation cascade, configuring the scenario of disseminated intravascular coagulation. Herein, we summarize the main COVID-19 features of relevance for the clinicians in the cardiovascular field. The rationale, concerns, and possible side effects of specific therapeutic measures, including anticoagulants, renin-angiotensin-aldosterone system inhibitors, and anti-inflammatory/antiviral medications applied to the treatment of COVID-19 are also discussed.

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

INTRODUCTION AND OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Unravelling the interplay between hyperkalaemia, renin-angiotensin-aldosterone inhibitor use and clinical outcomes. Data from 9222 chronic heart failure patients of the ESC-HFA-EORP Heart Failure Long-Term Registry

AIMS

We assessed the interplay between hyperkalaemia (HK) and renin-angiotensin-aldosterone system inhibitor (RAASi) use, dose and discontinuation, and their association with all-cause or cardiovascular death in patients with chronic heart failure (HF). We hypothesized that HK-associated increased death may be related to RAASi withdrawal.

METHODS AND RESULTS

The ESC-HFA-EORP Heart Failure Long-Term Registry was used. Among 9222 outpatients (HF with reduced ejection fraction: 60.6%, HF with mid-range ejection fraction: 22.9%, HF with preserved ejection fraction: 16.5%) from 31 countries, 16.6% had HK (≥5.0 mmol/L) at baseline. Angiotensin-converting enzyme inhibitor (ACEi) or angiotensin receptor blocker (ARB) was used in 88.3%, a mineralocorticoid receptor antagonist (MRA) in 58.7%, or a combination in 53.2%; of these, at ≥50% of target dose in ACEi: 61.8%; ARB: 64.7%; and MRA: 90.3%. At a median follow-up of 12.2 months, there were 789 deaths (8.6%). Both hypokalaemia and HK were independently associated with higher mortality, and ACEi/ARB prescription at baseline with lower mortality. MRA prescription was not retained in the model. In multivariable analyses, HK at baseline was independently associated with MRA non-prescription at baseline and subsequent discontinuation. When considering subsequent discontinuation of RAASi (instead of baseline use), HK was no longer found associated with all-cause deaths. Importantly, all RAASi (ACEi, ARB, or MRA) discontinuations were strongly associated with mortality.

CONCLUSIONS

In HF, hyper- and hypokalaemia were associated with mortality. However, when adjusting for RAASi discontinuation, HK was no longer associated with mortality, suggesting that HK may be a risk marker for RAASi discontinuation rather than a risk factor for worse outcomes.

Attainment of Guideline-Directed Medical Treatment in Stable Ischemic Heart Disease Patients With and Without Chronic Kidney Disease

BACKGROUND

Stable ischemic heart disease (SIHD) is prevalent in patients with chronic kidney disease (CKD); however, whether guideline-directed medical therapy (GDMT) is adequately implemented in patients with SIHD and CKD is unknown.

HYPOTHESIS

Use of GDMT and achievement of treatment targets would be higher in SIHD patients without CKD than in patients with CKD.

METHODS

This was a retrospective study of 563 consecutive patients with SIHD (mean age 67.8 years, 84% Caucasians, 40% females). CKD was defined as an estimated glomerular filtration rate (eGFR) of < 60 mL/min/1.73m² using the four-variable MDRD Study equation. We examined the likelihood of achieving GDMT targets (prescription of high-intensity statins, antiplatelet agents, renin-angiotensin-aldosterone system inhibitors (RAASi), and low-density lipoprotein cholesterol levels < 70 mg/dL, blood pressure < 140/90 mmHg, and hemoglobin A1C < 7% if diabetes) in patients with (n = 166) and without CKD (n = 397).

RESULTS

Compared with the non-CKD group, CKD patients were significantly older (72 vs 66 years; p < 0.001), more commonly female (49 vs 36%; p = 0.002), had a higher prevalence of diabetes (46 vs 34%; p = 0.004), and left ventricular systolic ejection fraction (LVEF) < 40% (23 vs. 10%, p < 0.001). All GDMT goals were achieved in 26% and 24% of patients with and without CKD, respectively (p = 0.712). There were no between-group differences in achieving individual GDMT goals with the exception of RAASi (CKD vs non-CKD: adjusted risk ratio 0.73, 95% CI 0.62-0.87; p < 0.001).

CONCLUSIONS

Attainment of GDMT goals in SIHD patients with CKD was similar to patients without CKD, with the exception of lower rates of RAASi use in the CKD group.

Epidemiology of hyperkalemia in chronic kidney disease

BACKGROUND

Hyperkalaemia is a significant electrolyte imbalance in chronic kidney disease (CKD). Renin-angiotensin-aldosterone system inhibitors (RAASi) have beneficial cardio-renal properties, although they can often cause hyperkalaemia.

OBJECTIVE

To examine the prevalence of hyperkalaemia in CKD, identify factors associated with its appearance and the relationship between hyperkalaemia and mortality.

PATIENTS AND METHODS

Retrospective observational study on patients with CKD in the period 1971-2017. The population was categorised into 3groups: Group 1, patients with CKD without renal replacement therapy; Group 2, patients on haemodialysis; and Group 3, patients on continuous ambulatory peritoneal dialysis.

RESULTS

A total of 2,629 patients were evaluated. The prevalence observed in the different groups was: 9.6%, 16.4% and 10.6%, respectively. Risk factors related to the appearance of hyperkalaemia in the CKD group were glomerular filtration rate (GFR) (P<.001), plasma creatinine (P<.001), plasma sodium (P<.001), haemoglobin (P=.028), diastolic blood pressure (P=.012), intake of ACE inhibitors and/or angiotensin ii receptor blockers (P=.008), treatment with metformin (P<.001) and diabetes (P=.045). Treatment with RAASi significantly increased hyperkalaemia as GFR decreased, as well as in patients with diabetes or heart failure.

CONCLUSIONS

Hyperkalaemia is a frequent metabolic alteration in CKD patients that increases in the presence of drugs with beneficial cardio-renal properties (RAASi), which means that patients often lose the benefit associated with these drugs. New, recently-appearing non-absorbable compounds, which bind to potassium in the gastrointestinal tract, enhancing faecal excretion and thus maintaining the cardio-renal benefit of the RAASi, could be relevant in the progress of patients with CKD.

Sodium zirconium cyclosilicate: a new potassium binder for the treatment of hyperkalemia

Hyperkalemia is one of the most common electrolyte disturbances, especially among some groups of patients, such as in those with chronic kidney disease, diabetes or heart failure. Hyperkalemia has been associated with increased risks of mortality, arrhythmias, hospitalization and costs, as well as the need to down titrate/discontinue renin-angiotensin-aldosterone system inhibitors (RAASIs), despite their well-known cardiovascular and nephroprotective benefits. Current potassium binders have limitations (slow onset of action, limited selectivity for potassium binding, risk of drug interactions or gastrointestinal intolerance). Sodium zirconium cyclosilicate (SZC) is a new potassium binder recently approved for the treatment of chronic hyperkalemia. It is a nonabsorbable, inorganic crystal which selectively binds potassium and ammonium in exchange of Na+ and H+ in the whole gastrointestinal tract, achieving a rapid correction of serum potassium levels (within 2 days) and maintaining normokalemia in the long term (up to 1 year), with a good safety profile (common adverse reactions include gastrointestinal events and a dose-dependent risk of edema), excellent tolerability and a low potential for drug interactions. Its potassium-lowering efficacy is maintained irrespective of the use of RAASIs. In summary, SZC is a new potassium binder recently approved for the treatment of hyperkalemia. Its differences with respect to currently available potassium binders make SZC an attractive therapeutic option.

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

Background

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

Methods and results

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

Conclusion

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

Potassium and the use of renin-angiotensin-aldosterone system inhibitors in heart failure with reduced ejection fraction: data from BIOSTAT-CHF

BACKGROUND

Hyperkalaemia is a common co-morbidity in patients with heart failure with reduced ejection fraction (HFrEF). Whether it affects the use of renin-angiotensin-aldosterone system inhibitors and thereby negatively impacts outcome is unknown. Therefore, we investigated the association between potassium and uptitration of angiotensin-converting enzyme inhibitors (ACEi)/angiotensin receptor blockers (ARB) and its association with outcome.

METHODS AND RESULTS

Out of 2516 patients from the BIOSTAT-CHF study, potassium levels were available in 1666 patients with HFrEF. These patients were sub-optimally treated with ACEi/ARB or beta-blockers and were anticipated and encouraged to be uptitrated. Potassium levels were available at inclusion and at 9 months. Outcome was a composite of all-cause mortality and heart failure hospitalization at 2 years. Patients' mean age was 67 ± 12 years and 77% were male. At baseline, median serum potassium was 4.3 (interquartile range 3.9-4.6) mEq/L. After 9 months, 401 (24.1%) patients were successfully uptitrated with ACEi/ARB. During this period, mean serum potassium increased by 0.16 ± 0.66 mEq/L (P < 0.001). Baseline potassium was an independent predictor of lower ACEi/ARB dosage achieved [odds ratio 0.70; 95% confidence interval (CI) 0.51-0.98]. An increase in potassium was not associated with adverse outcomes (hazard ratio 1.15; 95% CI 0.86-1.53). No interaction on outcome was found between baseline potassium, potassium increase during uptitration, or potassium at 9 months and increased dosage of ACEi/ARB (P_interaction  > 0.5 for all).

CONCLUSION

Higher potassium levels are an independent predictor of enduring lower dosages of ACEi/ARB. Higher potassium levels do not attenuate the beneficial effects of ACEi/ARB uptitration.