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Hyperkalemia is a potentially life-threatening condition frequently encountered in clinical practice, particularly among patients with chronic kidney disease, heart failure, diabetes, and hypertension and those undergoing treatment with renin-angiotensin-aldosterone system inhibitors (RAASi). The management of chronic and acute hyperkalemia is complex and requires timely intervention to prevent severe complications such as cardiac arrhythmias and sudden death. Traditional therapeutic approaches to chronic hyperkalemia, including dietary potassium restriction, use of diuretics, and administration of cation-exchange resins like sodium polystyrene sulfonate, often suffer from limitations like gastrointestinal side effects, variable efficacy, delayed onset of action, and RAASi treatment discontinuation. In recent years, the development of new potassium binders, specifically patiromer and sodium zirconium cyclosilicate (SZC), has revolutionized the management of hyperkalemia. Patiromer, a non-absorbed polymer, binds potassium in the gastrointestinal tract in exchange for calcium, thus facilitating its excretion. SZC operates by exchanging sodium and hydrogen ions for potassium, leading to efficient potassium removal. Both agents have demonstrated rapid and sustained reductions in serum potassium levels, coupled with favorable safety and tolerability profiles, in multiple clinical trials. This review article, authored by a multidisciplinary group of Portuguese experts in hyperkalemia management, provides an in-depth analysis of the efficacy and safety of current therapeutic strategies and highlights the clinical potential of new potassium binders. The introduction of patiromer and SZC offers significant advantages over traditional therapies, providing effective and better-tolerated options for patients. The review highlights the role of these novel agents in contemporary hyperkalemia management and calls for ongoing research to further refine treatment protocols and improve patient outcomes., Competing Interests: Declarations. Ethics approval: Not applicable. Consent for publication: All the authors have read and approved the final version of the manuscript and gave their consent for publication. Competing interests: C.F received consultancy fees, lectures, or sponsorship of scientific meetings from AstraZeneca, Bayer, Bial, Boehringer Ingelheim, Novartis, Novo Nordisk, Pfizer, Roche Diagnosis, Servier, CSL Vifor, companies that research and commercialize drugs for the treatment of heart failure patients. G.C. received speaking fees from Servier, Novartis, CSL Vifor, and Boehringer. C.G. is employed by Fresenius Medical Care as Head of the Nutrition Department. G.S. received speaking fees from CSL Vifor, AstraZeneca, Alnylam and Baxter. I.M. received speaking fees from AstraZeneca, Bayer, Bial, CSL Vifor, Daiichi-Sankyo, Novartis, Pfizer, Roche Diagnostics, and Servier. I.M. served on advisory boards for AstraZeneca, Bayer, Bial, CSL Vifor, Novartis, Novo Nordisk, and Servier. A.F. received Advisory Board and consultancy fees, lectures, or sponsorship of scientific meetings from AstraZeneca, Astellas, CSL Vifor, Fresenius Medical Care, MSD-Merck Sharp & Dohme companies., (© 2024. The Author(s).)

Two potassium (K + ) binders-patiromer sorbitex calcium and sodium zirconium cyclosilicate-are recommended by international guidelines for the management of hyperkalemia. There is, however, no universally accepted best practice for how to appropriately utilize K + binders in the long-term clinical management of CKD. A panel of eight US-based nephrologists convened in October 2022 to develop a consensus statement regarding utilizing K + binders in clinical practice to help manage patients with nonemergent, persistent/recurrent hyperkalemia in CKD. Consensus was reached on the following topics: (1) identifying risk factors for hyperkalemia; (2) serum K + monitoring before and during K + binder use; (3) utilizing K + binders in patients receiving renin-angiotensin-aldosterone system inhibitors and dialysis; and (4) when to initiate K + binders and their duration of use. These consensus statements for the use of K + binders may assist the nephrology community in optimizing management of hyperkalemia in patients across the spectrum of CKD., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Hyperkalemia is a common complication of chronic kidney disease (CKD). This study aims to investigate the efficacy and safety of sodium zirconium cyclosilicate and calcium polystyrene sulfonate in reducing potassium in patients with acute and severe hyperkalemia in CKD who are not undergoing dialysis., Materials and Methods: A retrospective real-world study was conducted among 73 patients with non-dialysis chronic kidney disease who were hospitalized in the First Affiliated Hospital of Chengdu Medical College from June 2020 to June 2022. 33 patients treated with sodium zirconium cyclosilicate were categorized as SZC group, and the other 40 patients treated with calcium polystyrene sulfonate were categorized as CPS group. Serum potassium, serum sodium, magnesium, calcium, and phosphorus levels were examined. Adverse reactions were recorded during medication., Results: Significantly decreased serum potassium was observed in both groups, whereas the potassium reduction was higher in the SZC group than in the CPS group at 2, 4, 24, and 48 hours after medication while there was no statistically significant difference in the serum potassium level between the two groups at 72 hours. For those people whose initial potassium exceeded 6 mmol/L, the potassium reduction was more obvious in the SZC group than in the CPS group at 2 and 4 hours after medication. The control rate of hyperkalemia in the SZC group was significantly higher than in the CPS group at 4, 24, and 48 hours. No distinct change was observed in serum sodium, calcium, magnesium, and phosphorus before and 72 hours after medication. No severe adverse reactions occurred., Conclusion: Sodium zirconium cyclosilicate has a more obvious effect on reducing potassium particularly for those patients with moderate to severe hyperkalemia who need rapid potassium reduction.

Background: Patiromer and sodium zirconium cyclosilicate (SZC) are 2 oral potassium binders approved for chronic hyperkalemia. It is unknown if one is more effective at reducing serum potassium than the other in acute hyperkalemia., Objective: The objective of this study was to determine if there was a difference between patiromer and SZC in the reduction of serum potassium in patients with acute hyperkalemia., Methods: This was a single-center, retrospective, observational study. Patients with a nonhemolyzed serum potassium level of 5.5 mEq/L or greater and received at least one dose of patiromer or SZC were included. The primary outcome was to determine the difference in effectiveness between patiromer and SZC in lowering of serum potassium 6 to 24 hours after administration. Secondary outcomes included description of total dosage received in 24 hours and incidence of electrolyte changes., Results: A total of 200 patients were included in this study, with 100 patients in each group. Serum potassium was significantly reduced by both patiromer (-1.2 mEq/L, 95% confidence interval [CI]: -2.3 to -0.2) and SZC (-0.8 mEq/L, 95% CI: -1.0 to -0.7), but there was no difference between the 2 medications in the amount of potassium reduction ( P = 0.464). No clinically significant differences in electrolyte changes were seen., Conclusions and Relevance: This study represents the first head-to-head comparison of patiromer and SZC in the setting of acute hyperkalemia. No difference in effectiveness between patiromer and SZC in reducing serum potassium was seen. Both agents can be considered in acute hyperkalemia management., Competing Interests: Declaration of Conflicting InterestsThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Introduction: Hyperkalemia, one of the most important electrolyte abnormalities of chronic kidney disease (CKD), often limits the use of renin-angiotensin-aldosterone system inhibitors and can increase in the postprandial period. In this study we report a real-world experience with the new non-adsorbed potassium binder patiromer in stage 3b-4 CKD patients. Moreover, we performed a cross-sectional analysis to evaluate, for the first time, the efficacy of patiromer in the control of postprandial potassium concentrations., Methods: We retrospectively collected data of 40 patients at the time of patiromer initiation (T0), and after 2 (T2), 6 (T6) and 12 (T12) months of treatment. For cross sectional analysis, a blood sample was collected 2 h after the main meal for the evaluation of postprandial potassium concentrations., Results: Eighty-two point five percent of patients (33/40) reached normal potassium concentrations at T2. Serum potassium significantly decreased at T2 compared to T0 (5.13 ± 0.48 vs 5.77 ± 0.41 mmol/L, respectively; p < 0.001) and the reduction remained significant during the follow-up (5.06 ± 0.36 at T6 and 5.77 ± 0.41 at T12; p < 0.001 vs T0). Renin-angiotensin-aldosterone system inhibitors were continued by 93% of patients (27/29). Adverse events were reported in 27.5% of patients and were all mild-to-moderate. Postprandial potassium concentrations did not significantly change compared to fasting state potassium measured at T12 (4.53 ± 0.33 vs 5.06 ± 0.36 mmol/L; p = 0.15)., Conclusions: In a real-world setting of advanced CKD patients, patiromer is a useful treatment for hyperkalemia, since it significantly reduces serum potassium levels over the long term and is able to maintain potassium concentrations in the normal range even in the post-prandial period., (© 2024. The Author(s) under exclusive licence to Italian Society of Nephrology.)

Background: Sodium zirconium cyclosilicate (SZC) is an approved oral treatment for hyperkalemia that selectively binds potassium (K + ) in the gastrointestinal tract and removes K + from the body through increased fecal excretion. Here, we describe the population pharmacodynamic (PopPD) response of serum K + concentration in patients with hyperkalemia who are treated with SZC, estimate the impact of patients' intrinsic and extrinsic factors, and compare predicted serum K + responses between 5 g alternate daily (QOD) and 2.5 g once daily (QD) maintenance doses., Methods: PopPD analysis was based on pooled data from seven phase II and III clinical trials for SZC. A semi-mechanistic longitudinal mixed-effects (base) model was used to characterize serum K + concentration after SZC dosing. Indirect-response, virtual pharmacokinetics-pharmacodynamics (PK-PD) modeling was used to mimic the drug exposure compartment. Full covariate modeling was used to assess covariate impact on the half-maximal effective concentration of drug (EC 50 ), placebo response, and K out . Models were evaluated using goodness-of-fit plots, relative standard errors, and visual predictive checks, and data were stratified to optimize model performance across subgroups. Covariate effects were evaluated based on the magnitude of change in serum K + between baseline and end of correction phase dosing (48 h, SZC 10 g three times a day) and maintenance phase dosing (28 days, SZC 10 g QD) using a reference subject., Results: The analysis data set included 2369 patients and 25,764 serum K + observations. The mean (standard deviation) patient age was 66.0 (12) years, 61% were male, 68% were White, 34% had congestive heart failure, and 62% had diabetes. Mean (standard deviation) serum K + at baseline was 5.49 (0.43) mmol/L. Both the base and full covariance models adequately described observed data. In the final model, there was a sigmoid exposure response on K in , with EC 50 of 32.8 g and a Hill coefficient of 1.36. The predicted placebo-adjusted dose-responses of serum K + change appeared nearly linear in the correction and maintenance phases. No clinically meaningful difference in placebo-adjusted serum K + change from baseline at 28 days was observed between maintenance regimens of SZC 5 g QOD and 2.5 g QD. A greater SZC treatment response was associated with high serum K + at baseline, advanced age, lower body weight, lower estimated glomerular filtration rate, and Black/African American and Asian race, compared with the reference patient. The impact of heart failure status and diabetes status was only minor., Conclusions: The PopPD model of SZC adequately described changes in serum K + concentration during correction and maintenance phase dosing. A greater treatment response was associated with various covariates, but the impact of each was modest. Overall, these findings suggest that no adjustment in SZC dose is needed for any of the covariates evaluated., (© 2024. The Author(s).)

Objective: Spironolactone (SPL) has been used to manage hyperandrogenic manifestations in women with polycystic ovary syndrome (PCOS), but data on the risk of hyperkalemia in this population are scarce. The aim of this study was to evaluate the incidence of hyperkalemia in women with PCOS using SPL in the long term., Design: Single-centre retrospective study., Patients: Inclusion and analysis of 98 treatment periods in 78 women with PCOS (20 of whom were duplicates, returning after treatment interruption for a mean of 38 months) who received SPL for a minimum of 12 months and had at least three measurements of potassium levels over time., Measurements: Clinical and hormonal profiles before and during SPL treatment., Results: Mean age was 29.1 (SD: 9.6) years, and body mass index was 32.2 (SD: 8.1) kg/m². Nine patients had diabetes, and 22 had prediabetes. SPL was used in combination with combined oral contraceptive pills in 55 participants and progestin-only pills/long-acting reversible contraception in 28; metformin was added in 35, and angiotensin-converting enzyme inhibitors/angiotensin receptor blockers in 15. Median SPL dose was 100 (range: 50-150) mg. A total of 327 serum potassium measurements were obtained (84 pre-exposure and 243 postexposure). Four potassium measurements were above the reference range before exposure and 19 during exposure. All potassium measurements above the reference range during follow-up were classified as mild hyperkalemia (5.1-5.5 mEq/L)., Conclusions: The present findings suggest that women with PCOS, without kidney or heart disease, using SPL combined with hormonal contraception for managing clinical hyperandrogenism have a low incidence of hyperkalemia and well-tolerated minor adverse effects., (© 2023 John Wiley & Sons Ltd.)

Problem: Hyperkalemia is a serious condition among intra-abdominal transplant recipients, and the safety and efficacy of sodium zirconium cyclosilicate (SZC) for its management during the early post-transplant period are not well-established., Methods: Adults who received at least one 10-g dose of SZC within 14 days after an intra-abdominal transplant between January 2020 and July 2022 were included in our study. The primary outcome was the change in potassium (K+) levels following the first SZC dose. Other analyses explored adjunctive potassium-lowering therapies, potential gastrointestinal complications, and patient subgroups based on therapy and transplant type., Results: Among the recipients (n = 46), 11 were kidney recipients, 26 were liver recipients, seven were simultaneous liver/kidney recipients, and two were simultaneous pancreas/kidney recipients. The mean time to first dose post-transplant was 7.6 (±4) days, and the mean change in serum K+ after the initial SZC dose was -.27 mEq (p = .001). No gastrointestinal complications were observed following the SZC dose. The mean increase in serum bicarbonate was .58 mEq (p = .41) following the first dose of SZC. Four kidney recipients required dialysis following the SZC dose., Conclusion: This study represents the largest investigation on the use of SZC in transplant recipients. A single 10-g dose of SZC reduced serum K+ levels in all subgroups, while the use of adjunctive K+-lowering therapies did not provide additional reduction beyond the effects of SZC. Importantly, no gastrointestinal complications were observed. These findings suggest that SZC may be a safe and promising therapeutic option for hyperkalemia management following solid organ transplantation., (© 2023 The Authors. Clinical Transplantation published by John Wiley & Sons Ltd.)

Background: Sodium zirconium cyclosilicate (SZC) is an effective and well-tolerated treatment for hyperkalemia in maintenance hemodialysis patients. In post-hoc analyses of the phase 3b DIALIZE study, we examined the spectrum of potassium responses to SZC., Methods: Post-hoc analyses with SZC and placebo included: the number of long interdialytic interval (LIDI) visits during the 4-week evaluation period where patients attained pre-dialysis serum potassium (sK + ) concentrations of 4.0-5.0 and 4.0-5.5 mmol/L; potassium gradient (the difference between pre-dialysis sK + and dialysate potassium) at days 36, 43, 50, and 57, and change from baseline to the end of treatment (EOT) using categories of potassium gradient (1 to < 2, 2 to < 3, 3 to < 4, and ≥ 4 mmol/L)., Results: A greater proportion of patients achieved the ranges of pre-dialysis sK + concentration with SZC versus placebo for ≥1, ≥ 2, ≥ 3, and 4 LIDI visits over 4 weeks; 23.7 and 48.5% of patients in the SZC group achieved pre-dialysis sK + concentrations of 4.0-5.0 and 4.0-5.5 mmol/L, respectively, at all 4 LIDI visits. Baseline mean potassium gradient was similar with SZC and placebo. At day 57, mean (standard deviation) potassium gradient was 2.78 (0.08) mmol/L with SZC and 3.52 (0.08) mmol/L with placebo; mean difference (95% confidence interval) was - 0.74 mmol/L (- 0.97 to - 0.52). A greater reduction in potassium gradient category from baseline towards lower-risk categories at EOT was observed with SZC versus placebo., Conclusions: These analyses expand our knowledge of the spectrum of potassium responses with SZC in hyperkalemic hemodialysis patients., Trial Registration: NCT03303521 ., (© 2022. The Author(s).)

Background: Hyperkalemia is an electrolyte disorder commonly encountered in the emergency department that can result in significant morbidity and mortality. While sodium bicarbonate is often used for acute lowering of serum potassium, its efficacy is not well established. The purpose of this study was to evaluate and quantify the amount of potassium reduction in emergency department patients who received intravenous sodium bicarbonate as part of treatment for hyperkalemia compared with those who did not., Methods: A retrospective electronic chart review was conducted on adult patients who presented to the emergency department with initial potassium concentration greater than or equal to 5.4 mMol/L and received intravenous insulin as part of hyperkalemia treatment. Patients who received intravenous sodium bicarbonate in addition to intravenous insulin were included in the sodium bicarbonate group. The control group included patients who did not receive intravenous sodium bicarbonate. The primary objective of this study was to compare the absolute reduction in serum potassium between initial and second concentrations in patients from the sodium bicarbonate group and those in the control group., Results: A total of 106 patients were included in this study with 38 patients in the sodium bicarbonate group and 68 patients in the control group. Median initial potassium concentration was 6.6 mMol/L in the sodium bicarbonate group and 6.1 mMol/L in the control group (P = 0.009). Absolute reduction of potassium at first repeat was 1 and 0.9 mMol/L in sodium bicarbonate group and control group respectively (P = 0.976)., Conclusions: The addition of sodium bicarbonate therapy to intravenous insulin in the treatment of hyperkalemia did not offer statistically significant added efficacy in potassium lowering. Larger studies are needed to further validate the result findings., Competing Interests: Declaration of Competing Interest Shiyi Geng: none. Emily Green: none. Jessica Rivera: none. Michael Kurz: funded by NIH 5U01DK096037 (Site PI); K23AG038548 (Site PI); R01GM101197 (Site PI); R01GM103799 (Site PI), American Heart Association, Society for Critical Care Medicine, Emergency Medicine Foundation, Rapid Pathogen Screening Inc, Boehringer-Ingelheim, Abbott, Zoll Medical Corporation, and Stryker Corporation to the University of Alabama at Birmingham., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Hyperkalemia is a common electrolyte abnormality in heart failure (HF) that can cause potentially life-threatening cardiac arrhythmias and sudden cardiac death. HF patients with diabetes, chronic kidney disease and older age are at higher risk of hyperkalemia. Moreover, hyperkalemia is also often associated with the use of renin-angiotensin-aldosterone system inhibitors (RAASi) including angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, mineralocorticoid receptor antagonists and sacubitril-valsartan. In clinical practice, the occurrence of hyperkalemia is a major concern among the clinicians and often limits RAASi use and/or lead to dose reduction or discontinuation, thereby reducing their potential benefits for HF. Furthermore, recurrent hyperkalemia is frequent in the long-term and is associated with an increase in hyperkalemia-related hospitalizations. Therefore, management of hyperkalemia has a special importance in HF patients. However, treatment options in chronic management are currently limited. Dietary restriction of potassium is usually ineffective with variable adherence. Sodium polystyrene sulfonate is commonly used, but its effectiveness is uncertain and reported to be associated with intestinal toxicity. New therapeutic options such as potassium binders have been suggested as potentially beneficial agents in the management of hyperkalemia. This document discusses prevalence, predictors and management of hyperkalemia in HF, emphasizing the importance of careful patient selection for medical treatment, uptitration of the doses of RAASi, regular surveillance of potassium and treatment options of hyperkalemia.

Hyperkalemia is an electrolyte abnormality with potentially life-threatening consequences. Despite various guidelines, no universally accepted consensus exists on best practices for hyperkalemia monitoring, with variations in precise potassium (K + ) concentration thresholds or for the management of acute or chronic hyperkalemia. Based on the available evidence, this review identifies several critical issues and unmet needs with regard to the management of hyperkalemia. Real-world studies are needed for a better understanding of the prevalence of hyperkalemia outside the clinical trial setting. There is a need to improve effective management of hyperkalemia, including classification and K + monitoring, when to reinitiate previously discontinued renin-angiotensin-aldosterone system inhibitor (RAASi) therapy, and when to use oral K + -binding agents. Monitoring serum K + should be individualized; however, increased frequency of monitoring should be considered for patients with chronic kidney disease, diabetes, heart failure, or a history of hyperkalemia and for those receiving RAASi therapy. Recent clinical studies suggest that the newer K + binders (patiromer sorbitex calcium and sodium zirconium cyclosilicate) may facilitate optimization of RAASi therapy. Enhancing the knowledge of primary care physicians and internists with respect to the safety profiles of these newer K + binders may increase confidence in managing patients with hyperkalemia. Lastly, the availability of newer K + -binding agents requires further study to establish whether stringent dietary K + restrictions are needed in patients receiving K + -binder therapy. Individualized monitoring of serum K + among patients with an increased risk of hyperkalemia and the use of newer K + -binding agents may allow for optimization of RAASi therapy and more effective management of hyperkalemia., (Copyright © 2020 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.)

Introduction: Hyperkalemia, defined as serum potassium level > 5.0 mEq/l, is associated with serious cardiac dysrhythmias, sudden death and increased mortality risk. It is common in patients with chronic kidney disease (CKD), diabetes (DM) and heart failure (HF), particularly in those treated with the renin-angiotensin-aldosterone system (RAAS) inhibitors or potassium-sparing diuretics. Although these drugs have documented renal and cardiac protective benefits, frequent hyperkalemia associated with their use often dictates administration of suboptimal doses or their discontinuation altogether. Treatment for chronic hyperkalemia in these settings has been challenging; however, the recent introduction of two new potassium-binding resins has revolutionized our approach to treating hyperkalemia., Areas Covered: We review key clinical data relating to the pharmacokinetics, efficacy and safety of sodium zirconium cyclosilicate (SZC) as a treatment option for hyperkalemia., Expert Opinion: SZC and Patiromer are promising new agents for lowering serum potassium in hyperkalemic patients, including those with CKD, with and without DM or HF, facilitating the use of the RAAS inhibitors for renal and cardiac protection. Recent randomized clinical trials have shown that SZC effectively lowers serum potassium and maintains normokalemia in most hyperkalemic patients. Clinical trials showed that SZC lowers serum potassium within 1 h, although it is not approved for treating acute hyperkalemia. SZC was well tolerated and associated with minimal adverse effects.

Background: Sodium zirconium cyclosilicate (SZC; formerly ZS-9) is a selective potassium (K+) binder for the treatment of adults with hyperkalaemia. This post hoc analysis of an open-label, single-arm trial (NCT02163499) compared SZC efficacy and safety >12 months among outpatients with hyperkalaemia and Stages 4 and 5 chronic kidney disease (CKD) versus those with Stages 1-3 CKD., Methods: Adults with serum K+ ≥5.1 mmol/L (measured by point-of-care i-STAT device) received SZC 10 g three times daily for 24-72 h until normokalaemia (i-STAT K+ 3.5-5.0 mmol/L) was achieved [correction phase (CP)], followed by once daily SZC 5 g for ≤12 months [maintenance phase (MP)]. Here, patients were stratified by baseline estimated glomerular filtration rate (eGFR <30 or ≥30 mL/min/1.73 m2). Study endpoints included percent achieving normokalaemia during CP and MP, mean serum K+ and bicarbonate during MP, and adverse events (AEs)., Results: Of 751 patients enrolled, 289 (39%), 453 (60%) and 9 (1%) had baseline eGFR values of <30, ≥30 mL/min/1.73 m2 or missing, respectively. During the CP, 82% of patients achieved normokalaemia in both eGFR subgroups within 24 h, and 100 and 95% with baseline eGFR <30 and ≥30 mL/min/1.73 m2, respectively, within 72 h. Corresponding proportions with normokalaemia during the MP were 82 and 90% at Day 365, respectively. Mean serum K+ reduction from baseline during the CP was sustained throughout the MP and serum bicarbonate increased. AEs during the MP were more common in the eGFR <30 ≥30 mL/min/1.73 m2 subgroup., Conclusions: SZC corrects hyperkalaemia and maintains normokalaemia among outpatients regardless of the CKD stage., (© The Author(s) 2020. Published by Oxford University Press on behalf of ERA-EDTA.)

Background: Sodium zirconium cyclosilicate (SZC) is an oral potassium binder approved to treat hyperkalemia in adults in a number of countries, including Japan., Methods: This phase 2/3, randomized, double-blind, placebo-controlled, dose-response study (ClinicalTrials.gov: NCT03127644) was designed to determine the efficacy and safety of SZC in Japanese adults with hyperkalemia. Patients with serum potassium (sK + ) concentrations ≥ 5.1- ≤ 6.5 mmol/L were randomized 1:1:1 to SZC 5 g, SZC 10 g, or placebo three times daily for 48 h (six doses total). The primary efficacy endpoint was the exponential rate of change in sK + over 48 h. The proportion of patients with normokalemia (sK + 3.5-5.0 mmol/L) at 48 h and adverse events (AEs) were also evaluated., Results: Overall, 103 patients (mean age, 73.2 years; range 50-89 years) received SZC 5 g (n = 34), SZC 10 g (n = 36), or placebo (n = 33). The exponential rate of sK + change from 0 to 48 h versus placebo was - 0.00261 (SZC 5 g) and - 0.00496 (SZC 10 g; both P < 0.0001). At 48 h, the proportions of patients with normokalemia were 85.3%, 91.7%, and 15.2% with SZC 5 g, SZC 10 g, and placebo, respectively. No serious AEs were reported. Hypokalemia (sK +  < 3.5 mmol/L) occurred in two patients in the SZC 10 g group; normokalemia was re-established within 6 days and no treatment-related AEs were reported., Conclusion: SZC is effective and well tolerated in Japanese patients with hyperkalemia.

Background: Hyperkalemia (HK) is a serious medical condition that can cause potentially fatal cardiac arrhythmias. Patients with heart failure (HF) are at risk of HK due to underlying chronic kidney disease and use of guideline-recommended renin-angiotensin-aldosterone system inhibitors. Patiromer, a sodium-free, non-absorbed potassium (K + ) binder, is indicated for the treatment of HK., Objective: To evaluate the consistency of patiromer's effect on lowering serum K + in patients with HF and HK using pooled data from three clinical trials., Methods: This post-hoc analysis evaluated the efficacy and safety of patiromer for management of HK over a 4-week treatment period using combined data from three clinical trials (AMETHYST-DN, OPAL-HK and TOURMALINE). Eligible patients had HK (serum K +  > 5.0 mEq/L) at study entry. Starting doses of patiromer ranged from 8.4 to 33.6 g/day. In this analysis, efficacy was assessed as the mean (± standard error [SE]) change in serum K + from baseline to Week 4. Safety outcomes evaluated included the incidence and severity of adverse events (AEs) during the 4-week treatment period., Results: In total, 653 patients who received ≥1 dose of patiromer were evaluable for efficacy (214 diagnosed with HF and 439 without HF). Mean baseline serum K + was 5.4 mEq/L. Patient characteristics were generally similar between the HF and non-HF subgroups. Serum K + decreased to <5.0mEq/L within one week of patients starting patiromer, reaching a nadir after 3 weeks in both the HF and non-HF subgroups (4.59 mEq/L and 4.64 mEq/L, respectively). The mean ± SE change from baseline to Week 4 in serum K + was -0.79 ± 0.06 mEq/L (95% CI: -0.91, -0.68) in patients with HF and - 0.75 ± 0.02 mEq/L (95% CI: -0.79, -0.70) in patients without HF. AEs occurred in 31% of patients with HF and 37% of patients without HF and were mostly mild or moderate in severity. The most common AEs were constipation (HF patients: 7%, non-HF patients: 5%) and diarrhea (HF patients: 2%, non-HF patients: 4%). AEs leading to discontinuation of patiromer occurred in 7% of patients with HF and in 3% of patients without HF., Conclusions: In this pooled analysis of patients with HK, patiromer was generally well tolerated and reduced serum K + similarly in patients with and without HF over 4 weeks., Competing Interests: Declaration of Competing Interest ILP is a consultant for the U.S. Food and Drug Administration/Center for Devices and Radiological Health; and serves on an advisory board for Relypsa, Inc., a Vifor Pharma Company. JY and GA are employees of Relypsa, Inc., a Vifor Pharma Company. HV has nothing to disclose., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Hyperkalemia is a frequent and sometimes life-threatening condition that may be associated with arrhythmia and cardiac dysfunction in patients with heart failure (HF). High potassium levels in HF represent both a direct risk for cardiovascular complication and an indirect biomarker of the severity of the underlying disease, reflecting neurohormonal activation and renal dysfunction. Evaluating the prevalence and significance of hyperkalemia in HF patients is essential for optimizing the use of potassium sparing agents, such the renin-angiotensin-aldosterone system inhibitors (RAASi) or angiotensin receptor-neprilysin inhibitors and mineralocorticoid receptor antagonists, which represent a well-established cornerstone and life-saving therapy. In this review we discuss recent findings and current concepts related to the epidemiology, pathological mechanisms and implications of hyperkalemia, as well as novel therapeutic approaches to counteract it in patients with HF. The balance between optimizing life-saving potassium sparing medication and minimizing hyperkalemia-associated risk is much needed in patients with HF. Although older potassium-binding agents are associated with serious adverse events, novel potassium-binding drugs are effective in lowering potassium levels and are generally well tolerated. Novel potassium-binding drugs, such as patiromer and sodium zirconium cyclosilicate, may help to optimize therapy in HF and achieve guideline-recommended doses. Hyperkalemia is common in HF patients and is associated with a poorer prognosis and an increased risk of cardiovascular complications: Contrariwise, "moderate" potassium levels go with a better prognosis, while the emergence of new drugs, potassium binders, could allow target doses of RAASi to be achieved., (© 2020 The Authors. Clinical Cardiology published by Wiley Periodicals, Inc.)

Hyperkalemia in heart failure is a condition that can occur with relative frequency because it is related to pathophysiological aspects of the disease, and favored by drugs that form the basis of chronic cardiac failure therapy. Often, associated comorbidities, such as kidney failure or diabetes mellitus can further adversely affect potassium levels. Hyperkalemia can result in acute and even severe clinical manifestations that put patients at risk. On the other hand, the finding of hyperkalemia in a chronic context can lead to a reduction in dosages or to suspension of drugs such as angiotensin-converting enzymes inhibitor, angiotensin receptor blocker, angiotensin receptor neprilysin inhibitor, and mineralcorticoid receptor antagonist, first line in the treatment of the disease, with negative effects in prognostic terms. Therapies for the correction of hyperkalemia have so far mainly concerned the treatment of acute clinical pictures. Newly developed molecules, such as patiromer or sodium zirconium cyclosilicate, now open new prospectives in the long-term management of hyperkalemia, and allow us to glimpse the possibility of a better titration of the cardinal drugs for heart failure, with consequent positive effects on patient prognosis. The aim of this review is to focus on the problem of hyperkalemia in the setting of heart failure, with particular regard to its incidence, its prognostic role, and the underlining pathophysiological mechanisms. The review also provides an overview of therapeutic strategies for correcting hyperkalemia in acute and chronic conditions, with a focus on the new potassium binders that promise to improve management of heart failure., Competing Interests: The author declares no conflicts of interest., (© 2020 Minà et al. Published by IMR press.)

Background: Hyperkalaemia is a common electrolyte abnormality caused by reduced renal potassium excretion in patients with chronic kidney diseases (CKD). Potassium binders, such as sodium polystyrene sulfonate and calcium polystyrene sulfonate, are widely used but may lead to constipation and other adverse gastrointestinal (GI) symptoms, reducing their tolerability. Patiromer and sodium zirconium cyclosilicate are newer ion exchange resins for treatment of hyperkalaemia which may cause fewer GI side-effects. Although more recent studies are focusing on clinically-relevant endpoints such as cardiac complications or death, the evidence on safety is still limited. Given the recent expansion in the available treatment options, it is appropriate to review the evidence of effectiveness and tolerability of all potassium exchange resins among people with CKD, with the aim to provide guidance to consumers, practitioners, and policy-makers., Objectives: To assess the benefits and harms of potassium binders for treating chronic hyperkalaemia among adults and children with CKD., Search Methods: We searched the Cochrane Kidney and Transplant Register of Studies up to 10 March 2020 through contact with the Information Specialist 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: Randomised controlled trials (RCTs) and quasi-randomised controlled studies (quasi-RCTs) evaluating potassium binders for chronic hyperkalaemia administered in adults and children with CKD., Data Collection and Analysis: Two authors independently assessed risks of bias and extracted data. Treatment estimates were summarised by random effects meta-analysis and expressed as relative risk (RR) or mean difference (MD), with 95% confidence interval (CI). Evidence certainty was assessed using GRADE processes., Main Results: Fifteen studies, randomising 1849 adult participants were eligible for inclusion. Twelve studies involved participants with CKD (stages 1 to 5) not requiring dialysis and three studies were among participants treated with haemodialysis. Potassium binders included calcium polystyrene sulfonate, sodium polystyrene sulfonate, patiromer, and sodium zirconium cyclosilicate. A range of routes, doses, and timing of drug administration were used. Study duration varied from 12 hours to 52 weeks (median 4 weeks). Three were cross-over studies. The mean study age ranged from 53.1 years to 73 years. No studies evaluated treatment in children. Some studies had methodological domains that were at high or unclear risks of bias, leading to low certainty in the results. Studies were not designed to measure treatment effects on cardiac arrhythmias or major GI symptoms. Ten studies (1367 randomised participants) compared a potassium binder to placebo. The certainty of the evidence was low for all outcomes. We categorised treatments in newer agents (patiromer or sodium zirconium cyclosilicate) and older agents (calcium polystyrene sulfonate and sodium polystyrene sulfonate). Patiromer or sodium zirconium cyclosilicate may make little or no difference to death (any cause) (4 studies, 688 participants: RR 0.69, 95% CI 0.11, 4.32; I 2 = 0%; low certainty evidence) in CKD. The treatment effect of older potassium binders on death (any cause) was unknown. One cardiovascular death was reported with potassium binder in one study, showing that there was no difference between patiromer or sodium zirconium cyclosilicate and placebo for cardiovascular death in CKD and HD. There was no evidence of a difference between patiromer or sodium zirconium cyclosilicate and placebo for health-related quality of life (HRQoL) at the end of treatment (one study) in CKD or HD. Potassium binders had uncertain effects on nausea (3 studies, 229 participants: RR 2.10, 95% CI 0.65, 6.78; I 2 = 0%; low certainty evidence), diarrhoea (5 studies, 720 participants: RR 0.84, 95% CI 0.47, 1.48; I 2 = 0%; low certainty evidence), and vomiting (2 studies, 122 participants: RR 1.72, 95% CI 0.35 to 8.51; I 2 = 0%; low certainty evidence) in CKD. Potassium binders may lower serum potassium levels (at the end of treatment) (3 studies, 277 participants: MD -0.62 mEq/L, 95% CI -0.97, -0.27; I 2 = 92%; low certainty evidence) in CKD and HD. Potassium binders had uncertain effects on constipation (4 studies, 425 participants: RR 1.58, 95% CI 0.71, 3.52; I 2 = 0%; low certainty evidence) in CKD. Potassium binders may decrease systolic blood pressure (BP) (2 studies, 369 participants: MD -3.73 mmHg, 95%CI -6.64 to -0.83; I 2 = 79%; low certainty evidence) and diastolic BP (one study) at the end of the treatment. No study reported outcome data for cardiac arrhythmias or major GI events. Calcium polystyrene sulfonate may make little or no difference to serum potassium levels at end of treatment, compared to sodium polystyrene sulfonate (2 studies, 117 participants: MD 0.38 mEq/L, 95% CI -0.03 to 0.79; I 2 = 42%, low certainty evidence). There was no evidence of a difference in systolic BP (one study), diastolic BP (one study), or constipation (one study) between calcium polystyrene sulfonate and sodium polystyrene sulfonate. There was no difference between high-dose and low-dose patiromer for death (sudden death) (one study), stroke (one study), myocardial infarction (one study), or constipation (one study). The comparative effects whether potassium binders were administered with or without food, laxatives, or sorbitol, were very uncertain with insufficient data to perform meta-analysis., Authors' Conclusions: Evidence supporting clinical decision-making for different potassium binders to treat chronic hyperkalaemia in adults with CKD is of low certainty; no studies were identified in children. Available studies have not been designed to measure treatment effects on clinical outcomes such as cardiac arrhythmias or major GI symptoms. This review suggests the need for a large, adequately powered study of potassium binders versus placebo that assesses clinical outcomes of relevance to patients, clinicians and policy-makers. This data could be used to assess cost-effectiveness, given the lack of definitive studies and the clinical importance of potassium binders for chronic hyperkalaemia in people with CKD., (Copyright © 2020 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.)

Objectives: Sodium zirconium cyclosilicate (SZC) is a novel, highly selective potassium binder currently approved in the United States and European Union for treatment of hyperkalemia. This pilot evaluation explored the efficacy of SZC with insulin and glucose as hyperkalemia treatment in the emergency department (ED)., Methods: This exploratory, phase II, multicenter, randomized, double-blind, placebo-controlled study (NCT03337477) enrolled adult ED patients with blood potassium ≥ 5.8 mmol/L. Patients were randomized 1:1 to receive SZC 10 g or placebo, up to three times during a 10-hour period, with insulin and glucose. The primary efficacy outcome was the mean change in serum potassium (sK + ) from baseline until 4 hours after start of dosing., Results: Overall, 70 patients were randomized (SZC n = 33, placebo n = 37), of whom 50.0% were male. Their mean (± standard deviation [±SD]) age was 59.0 (±13.8) years and mean initial sK + was similar between groups (SZC 6.4 mmol/L, placebo 6.5 mmol/L). The least squares mean (±SD) sK + change from baseline to 4 hours was -0.41 (±0.11) mmol/L and -0.27 (±0.10) mmol/L with SZC and placebo, respectively (difference = -0.13 mmol/L, 95% confidence interval [CI] = -0.44 to 0.17). A greater reduction in mean (±SD) sK + from baseline occurred with SZC compared with placebo at 2 hours: -0.72 (±0.12) versus -0.36 (±0.11) mmol/L (LSM difference = -0.35 mmol/L, 95% CI = -0.68 to -0.02), respectively. A numerically lower proportion of patients in the SZC group required additional potassium-lowering therapy due to hyperkalemia at 0 to 4 hours versus placebo (15.6% vs. 30.6%, respectively; odds ratio = 0.40, 95% CI = 0.09 to 1.77). Comparable proportions of patients experienced adverse events in both treatment groups at 0 to 24 hours., Conclusions: This pilot study suggested that SZC with insulin and glucose may provide an incremental benefit in the emergency treatment of hyperkalemia over insulin and glucose alone., (© 2020 The Authors. Academic Emergency Medicine published by Wiley Periodicals LLC on behalf of Society for Academic Emergency Medicine (SAEM).)

BACKGROUND Insulin lowers not only blood glucose levels but also serum potassium levels by driving potassium into the cells. Hypokalemia can occur during aggressive treatment of hypoglycemia in patients with insulin overdose and is a well-documented clinical phenomenon; however, there are no studies describing delayed hyperkalemia occurring after initial treatment in patients with insulin overdose. CASE REPORT A 23-year-old male with a history of type 2 diabetes mellitus and self-medicating with insulin, attempted suicide by subcutaneously injecting 2100 units of insulin. He was admitted to our emergency department due to recurrent hypoglycemia. Continuous administration of 50% glucose and potassium via a central venous catheter was performed to maintain his glucose levels above 80 mg/dL and serum potassium level between 3.5 and 4.0 mEq/L. Because his serum potassium level exceeded 4.5 mEq/L at day 3 after admission, the dosage was adjusted accordingly. After his serum potassium level declined to 3.0 mEq/L, his potassium level abruptly increased to 6.0 mEq/L at day 5 after admission. The patient was placed on a potassium-restricted diet and administered furosemide. Potassium infusion was also discontinued. After serum potassium levels returned to the normal range without interventional therapies, the patient was discharged to home on day 14. CONCLUSIONS In cases of high-dose insulin overdose, management of hyperkalemia following recovery from hypoglycemia is a critical aspect of patient management. Conservative administration of potassium to correct initial hypokalemia may be considered in patients with high-dose insulin overdose.

Hyperkalemia is a frequent finding in patients with chronic kidney disease (CKD). This increase in serum potassium levels is associated with decreased renal ion excretion, as well as the use of medications to reduce the progression of CKD or to control associated diseases such as diabetes mellitus and heart failure. Hyperkalemia increases the risk of cardiac arrhythmia episodes and sudden death. Thus, the control of potassium elevation is essential for reducing the mortality rate in this population. Initially, the management of hyperkalemia includes orientation of low potassium diets and monitoring of patients' adherence to this procedure. It is also important to know the medications in use and the presence of comorbidities to guide dose reduction or even temporary withdrawal of any of the potassium retention-related drugs. And finally, the use of potassium binders is indicated in both acute episodes and chronic hyperkalemia.

Hyperkalemia represents a common and potentially life-threating electrolyte abnormality, a complication frequently observed in patients with heart failure, kidney disease, diabetes or in those receiving drug therapies influencing the renin-angiotensin-aldosterone system. Elevated serum potassium levels are often the result of impaired urinary potassium elimination, inadequate or reduced cellular potassium uptake, severe heart failure, use of medications influencing potassium levels in the circulation, or, more commonly, a combination of these factors. Strategies for the treatment of nonemergent hyperkalemia include the use of cation-exchange resins, polymers or other novel mechanisms of potassium trapping, including sodium polystyrene sulfonate, patiromer and sodium zirconium cyclosilicate. These agents differ in their pharmacology and mechanism of action, clinical efficacy, including onset and extent of potassium-lowering effect, dosage and administration, and potential safety and adverse effect profiles. In this review, an evaluation of these characteristics, including clinical evidence and safety concerns, in the management of nonemergent hyperkalemia will be explored., (© The Author(s) 2019. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.)

Renin-angiotensin-aldosterone system inhibitors (RAASi) are now a standard treatment in most patients with cardiovascular disease, especially in those with heart failure (HF). The European Society of Cardiology and the American College of Cardiology/American Heart Association gave a Class IA recommendation for the use of RAASi in the treatment of Classes II-IV symptomatic HF with reduced ejection fraction (HFREF), based on their strong clinical benefits of lowering all-cause mortality and HF hospitalizations in these subjects. However, RAASi therapy or adding mineralocorticoid receptor antagonists in subjects receiving background angiotensin-converting enzyme inhibitors or angiotensin receptor blockers may be associated with an increased risk of hyperkalemia (HK), especially in those with reduced kidney function. As a result, a significant proportion of these subjects either have RAASi dose reduced or more often discontinued when they develop HK. Discontinuation of RAASi in patients hospitalized with HFREF was associated with higher postdischarge mortality and rehospitalization rates, while optimal dosing of RAASi significantly reduced median hospital stays, outpatient visits and related costs. Thus, effective treatment is required to lower potassium level and maintain normokalemia in subjects with HF and reduced kidney disease who develop or are at risk of HK, thus enabling them to continue their RAASi therapy and maximize benefits from RAASi. In this review, we provide an up-to-date review of the prevalence and significance of HK in patients with cardiorenal syndrome, as well as their optimal management of HK with recent novel therapies., (© The Author(s) 2019. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.)

Hyperkalemia is a common electrolyte disorder that may be rapidly life-threatening because of its cardiac toxicity. Hyperkalemia risk factors are numerous and often combined in the same patient. Most of the strategies to control serum potassium level in the short term have been used for decades. However, evidence for their efficacy and safety remains low. Treatment of hyperkalemia remains challenging, poorly codified, with a risk of overtreatment, including short-term side effects, and with the priority of avoiding unnecessary hospital stays or chronic medication changes. Recently, new oral treatments have been proposed for non-life-threatening hyperkalemia, with encouraging results. Their role in the therapeutic arsenal remains uncertain. Finally, a growing body of evidence suggests that hyperkalemia might negatively impact outcomes in the long term in patients with chronic heart failure or kidney failure through underdosing or withholding of cardiovascular medication (e.g. renin-angiotensin-aldosterone system inhibitors). Recognition of efficacy and potential side effects of treatment may help in tailoring treatments to the patient's status and conditions. In this review we discuss how treatment of hyperkalemia could be tailored to the patient's conditions and status, both on the short and mid term., (© The Author(s) 2019. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.)

Hyperkalemia (HK) is the most common electrolyte disturbance observed in patients with advanced stages of chronic kidney disease (CKD), is a potentially life-threatening clinical condition due to an increased risk of fatal arrhythmias, and strongly impacts the quality of life and prognosis of CKD patients. Moreover, while renin-angiotensin-aldosterone system inhibitors (RAASIs) represent the most cardio-nephro-protective drugs used in clinical practice, the treatment with these drugs per se increases serum potassium (sK) values, particularly when heart failure and diabetes mellitus coexist. In fact, the onset or recurrence of HK is frequently associated with not starting, down-titrating or withdrawing RAASIs, and is an indication to begin renal replacement treatment in end-stage renal disease. Current strategies aimed at preventing and treating chronic HK are still unsatisfactory, as evidenced by the relatively high prevalence of HK also in patients under stable nephrology care, and even in the ideal setting of randomized clinical trials. Indeed, dietary potassium restriction, the use of sodium bicarbonate or diuretics, the withdrawal or down-titration of RAASIs, or the administration of old potassium binders, namely sodium polystyrene sulphonate and calcium polystyrene sulphonate, have limited efficacy and are poorly tolerated; therefore, these strategies are not suitable for long-term control of sK. As such, there is an important unmet need for novel therapeutic options for the chronic management of patients at risk for HK. The development of new potassium binders may change the treatment landscape in the near future. This review summarizes the current evidence on the treatment of chronic HK in cardio-renal patients., (© The Author(s) 2019. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.)

Hyperkalemia is a common problem in both inpatients and outpatients. Many disease states (eg, chronic kidney disease) and medications may precipitate hyperkalemia. There are several drugs now available to treat hyperkalemia. Many of these drugs are relatively new. This review provides information regarding drug-induced causes of hyperkalemia and provides detailed information on the medications used to treat this problem.

Background and Objectives: Patiromer is a sodium-free, nonabsorbed, potassium-binding polymer that uses calcium as the counter-exchange ion and is approved for treatment of hyperkalemia. The 4-week TOURMALINE study in patients with hyperkalemia previously demonstrated that patiromer administered once daily reduces serum potassium similarly when given with or without food. We report a prespecified exploratory efficacy analysis as well as a post hoc efficacy and safety analysis of the TOURMALINE study on circulating markers of mineral metabolism., Design, Setting, Participants, & Measurements: Adults with hyperkalemia (potassium >5.0 mEq/L) were randomized to once-daily patiromer 8.4 g without/with food for 4 weeks, with doses adjusted to achieve and maintain serum potassium 3.8-5.0 mEq/L. Baseline and week 4 serum and 24-hour urine markers of mineral metabolism are reported for all patients combined (evaluable for efficacy, n =112; evaluable for safety, n =113). P values were calculated using a paired t test for change from baseline, unless otherwise specified., Results: Mean (SD) baseline eGFR was 41±26 ml/min per 1.73 m 2 . Mean (SD) changes from baseline to week 4 were 0.0±0.5 mg/dl ( P =0.78; n =100) for albumin-corrected serum calcium, -0.2±0.2 mg/dl ( P <0.001; n =100) for serum magnesium, and -0.1±0.7 mg/dl ( P =0.47; n =100) for serum phosphate. Median (quartile 1, quartile 3) changes in 24-hour creatinine-normalized urine calcium and phosphate from baseline to week 4 were 2.5 (-11.5, 23.7) mg/24 h ( P =0.10; n =69) and -43.0 (-162.6, 35.7) mg/24 h ( P =0.004; n =95), respectively. Median (quartile 1, quartile 3) changes in intact parathyroid hormone and 1,25-dihydroxyvitamin D from baseline to week 4 were -13 (-31, 4) pg/ml ( P <0.001; n =97) and -2 (-9, 3) pg/ml ( P =0.05; n =96), respectively. There were no changes in fibroblast growth factor-23 or 25-hydroxyvitamin D. In patients ( n =16) with baseline serum phosphate >4.8 mg/dL, the mean (SD) changes in serum and 24-hour creatinine-normalized urine phosphate from baseline to Week 4 were -0.6±0.8 mg/dl ( n =13) and -149.1±162.6 mg/24hr ( n =9), respectively., Conclusions: Patiromer lowered urine phosphate in all patients, and lowered both serum and urine phosphate in a small subset of patients with hyperphosphatemia. Intact parathyroid hormone and 1,25-dihydroxyvitamin D decreased, with no change in serum calcium., (Copyright © 2019 by the American Society of Nephrology.)

Background: Sodium zirconium cyclosilicate (SZC; formerly ZS-9) is a selective potassium (K+) binder for treatment of hyperkalemia. An open-label extension (OLE) of the -HARMONIZE study evaluated efficacy and safety of SZC for ≤11 months., Methods: Patients from HARMONIZE with point-of-care device i-STAT K+ 3.5-6.2 mmol/L received once-daily SZC 5-10 g for ≤337 days. End points included achievement of mean serum K+ ≤5.1 mmol/L (primary) or ≤5.5 mmol/L (secondary)., Results: Of 123 patients who entered the extension (mean serum K+ 4.8 mmol/L), 79 (64.2%) completed the study. The median daily dose of SZC was 10 g (range 2.5-15 g). The primary end point was achieved by 88.3% of patients, and 100% achieved the secondary end point. SZC was well tolerated with no new safety concerns., Conclusion: In the HARMONIZE OLE, most patients maintained mean serum K+ within the normokalemic range for ≤11 months during ongoing SZC treatment., (The Author(s). Published by S. Karger AG, Basel.)

Introduction: Hyperkalemia (potassium >5.0 mEq/L) affects heart failure patients with renal disease regardless of the use of renin-angiotensin-aldosterone system inhibitors (RAASi). The open-label TOURMALINE study showed that patiromer, a sodium-free, nonabsorbed potassium binder, lowers serum potassium of hyperkalemic patients similarly when given with or without food; unlike prior studies, patients were not required to be taking RAASi. We conducted post hoc analyses to provide the first report of patiromer in patients not taking RAASi., Methods: Hyperkalemic patients received patiromer, 8.4 g/d to start, adjusted to achieve and maintain serum potassium of 3.8 to 5.0 mEq/L. If taking RAASi, stable doses were required. The primary end point was the proportion of patients with serum potassium 3.8 to 5.0 mEq/L at week 3 or 4. This analysis presents data by patients taking or not taking RAASi., Results: Demographics and baseline characteristics were similar in patients taking (n = 67) and not taking RAASi (n = 45). Baseline mean (SD) serum potassium was 5.37 (0.37) mEq/L and 5.42 (0.43) mEq/L in patients taking and not taking RAASi, respectively. Mean (SD) daily patiromer doses were similar (10.7 [3.2] and 11.5 [4.0] g, respectively). The primary end point was achieved in 85% (95% confidence interval [CI]: 74-93) of patients taking RAASi and in 84% (95% CI: 71-94) of patients not taking RAASi. From baseline to week 4, the mean (SE) change in serum potassium was -0.67 (0.08) mEq/L in patients taking RAASi and -0.56 (0.10) mEq/L in patients not taking RAASi (both P < .0001 vs baseline, P = nonsignificant between groups). Adverse events were reported in 26 (39%) patients taking RAASi and 25 (54%) not taking RAASi; the most common adverse event was diarrhea (2% and 11%, respectively; no cases were severe). Five patients (2 taking RAASi) reported 6 serious adverse events; none considered related to patiromer., Conclusions: Patiromer was effective and generally well-tolerated for hyperkalemia treatment, whether or not patients were taking RAAS inhibitors.

Chronic hyperkalemia is a major complication of chronic kidney disease (CKD) that occurs frequently, heralds poor prognosis, and necessitates careful management by the nephrologist. Current strategies aimed at prevention and treatment of hyperkalemia are still suboptimal, as evidenced by the relatively high prevalence of hyperkalemia in patients under stable nephrology care, and even in the ideal setting of randomized trials where best treatment and monitoring are mandatory. The aim of this review was to identify and discuss a range of unresolved issues related to the management of chronic hyperkalemia in non-dialysis CKD. The following topics of clinical interest were addressed: diagnosis, relationship with main comorbidities of CKD, therapy with inhibitors of the renin-angiotensin-aldosterone system, efficacy of current dietary and pharmacological treatment, and the potential role of the new generation of potassium binders. Opinion-based answers are provided for each of these controversial issues.

Sodium zirconium cyclosilicate (Lokelma™) [hereafter referred to as SZC] is a non-absorbed, non-polymer zirconium silicate compound that preferentially exchanges hydrogen and sodium for potassium and ammonium ions in the gastrointestinal tract (GIT), thereby increasing faecal potassium excretion and lowering serum potassium levels. It is available as a powder for oral suspension (in water) and is approved in the EU and the USA for the treatment of hyperkalaemia in adults. In two multinational, phase III studies in adults with hyperkalaemia, SZC 10 g three times daily lowered serum potassium levels to within the normal range (3.5-5.0 mmol/L) during the first 48 h of treatment, and SZC 5 and 10 g once daily maintained normokalaemia over ≤ 28 days' therapy. These beneficial effects were consistent across all patient subgroups (e.g. chronic kidney disease, diabetes, heart failure, concomitant use of RAAS inhibitor therapy), and appeared to be maintained over the longer term (≤ 12 months). SZC was generally well tolerated in adults with hyperkalaemia. Its tolerability profile was generally similar to that seen with placebo over ≤ 28 day, and its safety profile appeared to remain consistent over the longer term (≤ 12 months). Moreover, the incidence of hypokalemia was low. Current evidence indicates that SZC is a promising therapy for the management of hyperkalaemia in adults.

Aims: Chronic kidney disease (CKD) in heart failure (HF) increases the risk of hyperkalaemia (HK), limiting angiotensin-converting enzyme inhibitor (ACE-I) or angiotensin receptor blocker (ARB) use. Patiromer is a sodium-free, non-absorbed potassium binder approved for HK treatment. We retrospectively evaluated patiromer's long-term safety and efficacy in HF patients from AMETHYST-DN., Methods and Results: Patients with Type 2 diabetes, CKD, and HK [baseline serum potassium >5.0-5.5 mmol/L (mild) or >5.5-<6.0 mmol/L (moderate)], with or without HF (New York Heart Association Class I and II, by investigator judgement), on ACE-I/ARB, were randomized to patiromer 8.4-33.6 g to start, divided twice daily. Overall, 105/304 (35%) patients had HF (75%, Class II). Mean (standard deviation) ejection fraction (EF) was 44.9% (8.2) (n = 81) in patients with HF; 26 had EF ≤40%. In HF patients, mean serum potassium decreased by Day 3 through Week 52. At Week 4, estimated mean (95% confidence interval) change in serum potassium was -0.64 mmol/L (-0.72, -0.55) in mild and -0.97 mmol/L (-1.14, -0.80) in moderate HK (both P < 0.0001). Most HF patients with mild (>88%) and moderate (≥73%) HK had normokalaemia at each visit from Weeks 12 to 52. Three HF patients were withdrawn because of high (n = 1) or low (n = 2) serum potassium. The most common patiromer-related adverse event was hypomagnesaemia (8.6%)., Conclusions: In patients with a clinical diagnosis of HF, diabetes, CKD, and HK on ACE-I/ARB, patiromer was well tolerated and effective for HK treatment over 52 weeks., (© 2018 The Authors. ESC Heart Failure published by John Wiley & Sons Ltd on behalf of the European Society of Cardiology.)

Patiromer (Veltassa ® ) for oral suspension is a non-absorbed, sodium-free potassium binding polymer that exchanges calcium for potassium in the gastrointestinal (GI) tract, thereby increasing faecal potassium excretion and reducing serum potassium levels. Patiromer was approved in the USA in 2015 and is now approved in several other countries, including those of the EU, for the treatment of hyperkalaemia in adults. In clinical trials, patiromer reduced serum potassium levels and the risk of recurrent hyperkalaemia in patients with chronic kidney disease (CKD) and/or diabetic nephropathy with or without heart failure (HF), allowing the majority of patients to continue receiving renin-angiotensin-aldosterone system (RAAS) inhibitors (drugs that inhibit the renal excretion of potassium) for up to 52 weeks. Patiromer also maintained normokalaemia in patients with HF and a propensity for hyperkalaemia, enabling concomitant administration and up-titration of spironolactone. Patiromer was generally well tolerated, with a low risk of hypokalaemia. GI disorders and hypomagnesaemia were the most common adverse events; these were generally of mild or moderate severity. Therefore, oral patiromer is a valuable treatment option for the long-term management of hyperkalaemia.

Introduction: Hyperkalemia (HK) occurs often among patients with chronic kidney disease (CKD) and heart failure (HF) and those treated with renin-angiotensin-aldosterone system inhibitors (RAASI). Even small deviations from normal potassium levels carry increased risk of mortality. Patiromer is approved for treatment of HK and has been shown in clinical trials to reduce serum potassium among patients with HK and comorbid conditions. Areas covered: We review pooled data from two clinical trials of patiromer in patients with CKD and HK, safety of patiromer in special populations, drug-drug interaction (DDI) studies, and other studies in healthy volunteers. Expert opinion: Potassium must be maintained within a narrow range to avoid increased risk of mortality. Patients with CKD and HF and those receiving RAASI require careful monitoring of potassium levels. Patiromer effectively reduces serum potassium, and gastrointestinal adverse events (AEs) are the most common patiromer-associated AEs. Effective management of HK with patiromer may allow use of RAASI at optimal doses as recommended by treatment guidelines. Future research should examine the potential for potassium binders, including patiromer, to extend use of RAASI in appropriate patient populations.

The amiloride-sensitive epithelial sodium channel (ENaC) and the thiazide-sensitive sodium chloride cotransporter (NCC) are key regulators of sodium and potassium and colocalize in the late distal convoluted tubule of the kidney. Loss of the α ENaC subunit leads to a perinatal lethal phenotype characterized by sodium loss and hyperkalemia resembling the human syndrome pseudohypoaldosteronism type 1 (PHA-I). In adulthood, inducible nephron-specific deletion of α ENaC in mice mimics the lethal phenotype observed in neonates, and as in humans, this phenotype is prevented by a high sodium (HNa + )/low potassium (LK + ) rescue diet. Rescue reflects activation of NCC, which is suppressed at baseline by elevated plasma potassium concentration. In this study, we investigated the role of the γ ENaC subunit in the PHA-I phenotype. Nephron-specific γ ENaC knockout mice also presented with salt-wasting syndrome and severe hyperkalemia. Unlike mice lacking α ENaC or β ΕΝaC, an HNa + /LK + diet did not normalize plasma potassium (K + ) concentration or increase NCC activation. However, when K + was eliminated from the diet at the time that γ ENaC was deleted, plasma K + concentration and NCC activity remained normal, and progressive weight loss was prevented. Loss of the late distal convoluted tubule, as well as overall reduced β ENaC subunit expression, may be responsible for the more severe hyperkalemia. We conclude that plasma K + concentration becomes the determining and limiting factor in regulating NCC activity, regardless of Na + balance in γ ENaC-deficient mice., (Copyright © 2018 by the American Society of Nephrology.)

Hyperkalemia (serum potassium > 5.5 mEq/L) is a common clinical problem in patients with chronic kidney disease, hypertension, diabetes, and heart failure. It can result from increased K + intake, impaired distribution between intracellular and extracellular spaces, and most frequently, decreased renal excretion. Patients at the highest risk of hyperkalemia are treated with renin-angiotensin-aldosterone system inhibitors (RAASIs) as they improve cardiovascular and renal outcomes and are strongly recommended in clinical guidelines. However, RAASIs cause or increase the risk of hyperkalemia, a key limitation to fully titrate RAASIs in patients who are most likely to benefit from treatment. Until recently, drugs for the treatment of hyperkalemia presented limited efficacy and/or safety concerns and there was an unmet need of new drugs to control hyperkalemia while maintaining RAASI therapy. We provide an overview of the mechanisms involved in K + homeostasis and the epidemiology and management of hyperkalemia as a complication in cardiovascular patients and, finally, analyze the efficacy and safety of two new polymer-based, non-systemic agents, patiromer calcium and sodium zirconium cyclosilicate (ZS-9), designed to increase fecal K + loss and to normalize elevated serum K + levels and chronically maintain K + homeostasis in hyperkalemic patients treated with RAASIs.

Among patients with proteinuric chronic kidney disease (CKD), current guideline recommendations mandate the use of agents blocking the renin angiotensin aldosterone system (RAAS) as first-line antihypertensive therapy based on randomized trials demonstrating that RAAS inhibitors are superior to other antihypertensive drug classes in slowing nephropathy progression to end-stage renal disease. However, the opportunities for adequate RAAS blockade in CKD are often limited, and an important impediment is the risk of hyperkalemia, especially when RAAS inhibitors are used in maximal doses or are combined. Accordingly, a large proportion of patients with proteinuric CKD may not have the anticipated renoprotective benefits since RAAS blockers are often discontinued due to incident hyperkalemia or are administered at suboptimal doses for fear of the development of hyperkalemia. Two newer potassium binders, patiromer and sodium zirconium cyclosilicate (ZS-9), have been shown to effectively and safely reduce serum potassium levels and maintain long-term normokalemia in CKD patients receiving background therapy with RAAS inhibitors. Whether these novel potassium-lowering therapies can overcome the barrier of hyperkalemia and enhance the tolerability of RAAS inhibitor use in proteinuric CKD awaits randomized trials., (Published by Elsevier Inc.)

Maintaining potassium balance in the body is essential for cellular function. Even a slight increase in normal serum potassium levels (3.5-5.0 mEq/L) can interfere with metabolism, electrical action potentials, and cellular processes. Hyperkalemia is commonly seen in patients with chronic kidney disease (CKD) and in patients on renin-angiotensin-aldosterone system (RAAS) inhibitors. Sodium polystyrene sulfonate (SPS), diuretics, and hemodialysis are currently available methods for removing potassium from the body; however, these options have their limitations. Patiromer (Veltassa) and sodium zirconium cyclosilicate are 2 new therapeutic options that can potentially lead a new frontier in the management of hyperkalemia. This article will review these novel treatments.

Hyperkalemia, defined as serum potassium concentrations greater than 5.0 to 5.5 mEq/L, is a frequent occurrence in clinical practice because of the increasing incidence and prevalence of CKD. Patients at risk for this disorder are commonly treated with drugs that interfere in the renin-angiotensin-aldosterone system, thereby enhancing the occurrence and prevalence of this disorder. Discontinuation of these drugs because of the development of hyperkalemia deprives these patients the renal-protective and cardiovascular benefits this class of pharmacology has been shown to provide. Here we provide the clinician strategies to both prevent and treat hyperkalemia in patients with CKD who are prescribed these drugs. We emphasize the importance of limiting dietary potassium intake and avoiding either prescribed or over-the-counter medications that may impair renal potassium excretion. We discuss the role of kaliuretic diuretics and correction of metabolic acidosis as a therapeutic strategy. Additionally, we discuss the role of new agents designed to bind potassium in the gastrointestinal tract that can be used to maintain normokalemia in patients who previously developed hyperkalemia on renin-angiotensin-aldosterone blockers. Finally, we provide a brief discussion on how best to treat hypokalemia in patients with CKD., (Copyright © 2017 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.)

Disturbances of potassium homeostasis can cause either hyperkalemia or hypokalemia and result in serious consequences. Although the consequences of acute and chronic hyperkalemia and treatment of these conditions in CKD have been widely appreciated by nephrologists, more recent information has focused attention on the consequences of chronic hypokalemia. Several recent studies have documented a "U-shaped" relationship between the serum [K + ] and higher mortality in several clinical studies. The causes of dyskalemias are placed into the unique perspective of patients with CKD and its evolution with progression of CKD to later stages and focuses on the pathophysiology of these disorders. Emphasis is placed on the high mortality associated with both low and high levels of potassium that are unique to patients with CKD. Recent information regarding sensors of changes in the serum [K + ] that evoke changes in NaCl transport in the DCT1 and subsequent efferent responses by aldosterone-responsive cells in the DCT2 and cortical collecting duct to adjust K + secretion by the renal outer medullary potassium channel is reviewed in detail. These sensing mechanisms can be interrupted by drugs, such as the calcineurin inhibitors to cause both hypertension and hyperkalemia in kidney transplant patients, or can be inherited as familial hypertensive hyperkalemia. The role and pathogenesis of angiotensin-converting enzyme inhibitors and angiotensin receptor blockers in causing hyperkalemia is a common stop point for cessation of these important drugs, but, and newer agents to lower the serum [K + ] that might allow continuation of angiotensin-converting enzyme or angiotensin receptor blocker therapy are examined. Finally, the importance of emphasis on potassium-containing foods, such as fresh produce and fruit in the diets of patients with early-stage CKD, is examined as an under-appreciated area requiring more emphasis by nephrologists caring for these patients and may be unique to food-challenged patients with CKD., (Copyright © 2017 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.)

Aims: Co-trimoxazole maintains a well-established role in the treatment of Pneumocystis jirovecii and Toxoplasma gondii, as well as urinary tract infections. Observational studies report hyperkalaemia to be associated with co-trimoxazole, which may stem from an amiloride-like potassium-sparing effect. The current study investigated changes in serum potassium in patients without acute infections, and the influence of concomitant antikaliuretic drugs on this effect., Methods: A post hoc analysis was carried out of a randomized controlled trial in patients with interstitial lung disease who were assigned to placebo or 960 mg co-trimoxazole twice daily. Serum potassium and creatinine were measured at baseline, 6 weeks, and 6, 9 and 12 months. The primary outcome was the difference in mean serum potassium concentrations between co-trimoxazole and placebo at 6 weeks., Results: Mean serum potassium levels were similar at baseline: 4.24 (± 0.44) mmol l -1 in the 87 co-trimoxazole group participants and 4.25 (± 0.39) mmol l -1 in the 83 control participants. Co-trimoxazole significantly increased mean serum potassium levels at 6 weeks, with a difference between means compared with placebo of 0.21 mmol l -1 [95% confidence interval (CI) 0.09, 0.34; P = 0.001). This significant increase in serum potassium was detectable even after exclusion of patients on antikaliuretic drugs, with a difference between means for co-trimoxazole compared with placebo of 0.23 mmol l -1 (95% CI 0.09, 0.38; P = 0.002). There were 5/87 (5.7%) patients on co-trimoxazole whose serum potassium concentrations reached ≥5.5 mmol l -1 during the study period., Conclusions: Co-trimoxazole significantly increases serum potassium concentration, even in participants not using antikaliuretic drugs. While the magnitude of increase was often minor, a small proportion in our outpatient cohort developed hyperkalaemia of clinical importance., (© 2017 The British Pharmacological Society.)

The kidney plays an essential role in maintaining homeostasis of ion concentrations in the blood. Because the concentration gradient of potassium across the cell membrane is a key determinant of the membrane potential of cells, even small deviations in serum potassium level from the normal setpoint can lead to severe muscle dysfunction, resulting in respiratory failure and cardiac arrest. Less severe hypo- and hyperkalemia are also associated with morbidity and mortality across various patient populations. In addition, deficiencies in potassium intake have been associated with hypertension and adverse cardiovascular and renal outcomes, likely due in part to the interrelated handling of sodium and potassium by the kidney. Here, data on the beneficial effects of potassium on blood pressure and cardiovascular and renal outcomes will be reviewed, along with the physiological basis for these effects. In some patient populations, however, potassium excess is deleterious. Risk factors for the development of hyperkalemia will be reviewed, as well as the risks and benefits of existing and emerging therapies for hyperkalemia.

Background: Hyperkalemia is a frequently observed electrolyte imbalance in dehydrated neonatal diarrheic calves that can result in skeletal muscle weakness and life-threatening cardiac conduction abnormalities and arrhythmias., Hypothesis: Intravenous administration of a small-volume hypertonic NaHCO 3 solution is clinically more effective in decreasing the plasma potassium concentration (cK) in hyperkalemic diarrheic calves than hypertonic NaCl or glucose solutions., Animals: Twenty-two neonatal diarrheic calves with cK >5.8 mmol/L., Methods: Prospective randomized clinical trial. Calves randomly received either 8.4% NaHCO 3 (6.4 mL/kg BW; n = 7), 7.5% NaCl (5 mL/kg BW; n = 8), or 46.2% glucose (5 mL/kg BW; n = 7) IV over 5 minutes and were subsequently allowed to suckle 2 L of an electrolyte solution. Infusions with NaHCO 3 and NaCl provided an identical sodium load of 6.4 mmol/kg BW., Results: Hypertonic NaHCO 3 infusions produced an immediate and sustained decrease in plasma cK. Hypertonic glucose infusions resulted in marked hyperglycemia and hyperinsulinemia, but cK remained unchanged for 20 minutes. Between 30 and 120 minutes after initiation of treatment, the most marked decrements in cK from baseline occurred in group NaHCO 3 , which were significantly (P < .05) larger during this period of time than in calves in group NaCl, but not group glucose. After 120 minutes, the mean decrease in cK from baseline was -26 ± 10%, -9 ± 8%, and -22 ± 6% in groups NaHCO 3 , NaCl, and glucose, respectively., Conclusions/clinical Importance: Small-volume hypertonic NaHCO 3 infusions appear to have clinical advantages for the rapid resuscitation of hyperkalemic diarrheic calves, compared to hypertonic NaCl or glucose solutions., (Copyright © 2017 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.)