Hyperkalemia and renin-angiotensin aldosterone system inhibitor therapy in chronic kidney disease: A general practice-based, observational study

Impaired aldosterone response to potassium and hyperkalemia in patients receiving a renin-angiotensin-aldosterone system inhibitor

BACKGROUND/AIMS

Angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin II receptor blockers (ARBs) are associated with the development of hyperkalemia. We evaluated the relationship between the serum aldosterone-to-potassium ratio (APR) and the risk of developing hyperkalemia in patients with chronic kidney disease (CKD) receiving ACEIs or ARBs.

METHODS

One hundred eighty-six patients with stage 3-4 CKD receiving an ACEI or ARB for at least 3 months were evaluated. Serum aldosterone and potassium concentrations were measured simultaneously, and serum APR was calculated (ng/mL per mmol/L). Patients were divided into two groups for comparison according to the median value above or below 2.42. The primary outcome was the difference between the two groups in the development of hyperkalemia (defined as a serum potassium level > 5.5 mmol/L). Incidence rates and risk factors of hyperkalemia were assessed.

RESULTS

During the follow-up period, 144 hyperkalemic events in 81 patients (43.5%) were identified, yielding an incidence rate of 24.6 events/100 person-years. The incidence rate was significantly higher in patients with a low serum APR than in patients with a high APR (35.8 events/100 patient-years vs. 12.9 events/100 patient-years, p < 0.001). In addition, diabetes mellitus, history of hyperkalemia, CKD progression during the follow-up period, and low serum APR were predictors of the development of hyperkalemia.

CONCLUSION

Low serum APR was associated with the occurrence of hyperkalemia in patients with CKD receiving ACEIs or ARBs, suggesting that the identification of patients administered these drugs who are at high risk for hyperkalemia may be achieved using this index.

The burden of hyperkalaemia in chronic kidney disease: a systematic literature review

Background

The global epidemiology and burden of hyperkalaemia in patients with chronic kidney disease (CKD) are unclear due to the inconsistent definitions of hyperkalaemia. The combination of adverse effects and interaction between comorbidity and pharmacotherapies, such as renin-angiotensin-aldosterone system inhibitors (RAASi), justify a systematic understanding of this common complication of CKD.

Methods

This systematic literature review aimed to identify and descriptively summarize the evidence on hyperkalaemia risk factors and associated characteristics in adult CKD patients, including the effects of sub-optimal RAASi. Medline® and Embase® databases were searched from January 2000 to April 2024, with additional hand searching. Publications were screened by two independent reviewers. Data were extracted by one reviewer and verified by another reviewer; study quality assessment was also conducted.

Results

A total of 138 studies described in 145 publications met the eligibility criteria. The published literature revealed varying prevalence of hyperkalaemia amongst inconsistent definitions and a significant increase in the prevalence and incidence of hyperkalaemia among patients with CKD, regardless of RAASi treatment. Hyperkalaemia was associated with adverse outcomes and increased hospital resource use. Additionally, studies pointed to negative health and economic outcomes due to sub-optimal RAASi dosing in CKD patients with hyperkalaemia, as well as in those with CKD and comorbid heart failure.

Conclusions

This review expands on current research, offering a new perspective specifically focused on CKD patients and wider clinical and economic outcomes. Identification of wider clinical and economic consequences of hyperkalaemia in CKD patients, and the interplay between these risks and the risks of sub-optimal RAASi dosing, justify the need for future research. Clinicians should exercise caution when managing this condition in this complex patient group.

SGLT2 Inhibitors and Risk for Hyperkalemia Among Individuals Receiving RAAS Inhibitors

Importance

Hyperkalemia is a common complication of taking a renin-angiotensin-aldosterone system inhibitor (RAASi). Post hoc analyses of large randomized clinical trials suggested that the addition of sodium-glucose cotransporter 2 inhibitors (SGLT2i) may attenuate this risk. It is unknown if this observation extends to daily clinical practice.

Objective

To evaluate the association between SGLT2i initiation and hyperkalemia in individuals receiving RAASi with a background of diabetes, heart failure, or chronic kidney disease.

Design, Setting, and Participants

This population-based retrospective cohort study was conducted in Ontario, Canada, from July 1, 2015, to June 30, 2021. The cohort comprised adults 66 years and older who were prescribed a RAASi and had a history of diabetes or heart failure, an estimated glomerular filtration rate of less than 45 mL/min/1.73 m2, and/or a urine albumin to creatinine ratio of greater than 30 mg/mmol. The data were analyzed between March 28, 2023, and March 22, 2024.

Exposure

The study exposure was a new prescription of an SGLT2i compared to noninitiation of an SGLT2i. Inverse probability of treatment weighting by a propensity score for the receipt of SGLT2i was used to achieve balance of baseline covariates in both exposure groups.

Main Outcomes and Measures

The primary study outcome was hyperkalemia, defined as a serum potassium of greater than 5.5 mEq/L or an administrative code for an inpatient or outpatient encounter with hyperkalemia within 1 year of the index date.

Results

A total of 20 063 individuals who initiated an SGLT2i (mean [SD] age, 76.9 [6.6] years; 12 020 [59.9%] male) were compared to a pseudopopulation of 19 781 nonusers (mean [SD] age, 76.8 [7.0] years; 11 731 [59.3%] male). In the overall cohort, 95% had diabetes, 17% had heart failure, and 32% had stage 3 to 5 chronic kidney disease. SGLT2i initiation was associated with a lower risk of hyperkalemia (hazard ratio, 0.89 [95% CI, 0.82-0.96]). SGLT2i users had a significantly lower rate of RAASi discontinuation compared to nonusers (36% vs 45%; P < .001).

Conclusions and Relevance

This cohort study demonstrated that, among individuals with diabetes, heart failure, or chronic kidney disease who were receiving a RAASi, SGLT2i initiation was associated with a lower risk of hyperkalemia and RAASi discontinuation.

Initiating renin-angiotensin system inhibitors in chronic kidney disease

Chronic kidney disease (CKD) is a heterogeneous group of disorders characterised by abnormalities in kidney structure or function, present for at least 3 months. Renin-angiotensin system (RAS) inhibitors are established treatments in the management of CKD, reducing the risk of adverse kidney and cardiovascular events. Despite an extensive evidence base and decades of clinical experience, they remain underused, underdosed and frequently discontinued due to concerns about changes in kidney function and hyperkalaemia. In this article, we provide an overview of initiating RAS inhibitors in adults with CKD, highlight current guideline recommendations and offer a practical approach to dealing with the challenges associated with their use.

Consequences of Recurrent Hyperkalemia on Cardiovascular Outcomes and Mortality

Background

Hyperkalemia (HK) has been linked to serious cardiovascular (CV) outcomes, but the impact of recurrent HK on these outcomes is ill-defined.

Objectives

This study evaluated mortality and CV outcomes associated with recurrent HK vs normokalemia in patients with chronic kidney disease (CKD) and in a subset of patients with co-occurring heart failure (HF).

Methods

REVOLUTIONIZE III was a retrospective cohort study of adults (aged ≥18 years) diagnosed with stage 3/4 CKD, with or without HF in Optum's deidentified Market Clarity database (January 2016 to August 2022). Patients with recurrent HK (≥2 events) were exactly and propensity score-matched to patients with normokalemia (no serum [K+] <3.5 or >5.0 mmol/L or HK diagnosis ever). The primary endpoint was all-cause mortality; secondary endpoints were CV outcomes including major adverse CV events plus (major adverse cardiovascular event or hospitalization with heart failure [MACE+]; defined as all-cause mortality or hospitalized myocardial infarction, stroke, or HF and hospitalized arrhythmia). Cause-specific Cox proportional hazard models were used to compare outcomes between cohorts.

Results

The study included 6,337 matched pairs overall, including 2,129 with HF. Characteristics of the samples were well-balanced. Recurrent HK was associated with higher risks of all-cause mortality (HR overall: 1.29 [95% CI: 1.20-1.38]; HF substudy: 1.30 [95% CI: 1.18-1.44]), MACE+ (overall: 1.53 [95% CI: 1.43-1.65]; HF substudy: 1.45 [95% CI: 1.29-1.64]), and hospitalized arrhythmia (overall: 1.94 [95% CI: 1.74-2.16]; HF substudy: 1.85 [95% CI: 1.55-2.21]) compared with normokalemia.

Conclusions

In patients with CKD, recurrent HK increased the risks of all-cause mortality, MACE+, and hospitalized arrhythmia compared with normokalemia, including in a subset of patients with HF.

Economic burden of recurrent hyperkalemia in patients with chronic kidney disease

BACKGROUND

Hyperkalemia is a common complication of chronic kidney disease (CKD) and can become recurrent in half of cases. However, the incremental economic burden associated with recurrent hyperkalemia is unknown.

OBJECTIVE

To evaluate all-cause health care resource utilization (HRU) and medical costs in patients with stage 3/4 CKD with recurrent hyperkalemia vs normokalaemia and vs nonrecurrent hyperkalemia.

METHODS

Data were from Optum's de-identified Market Clarity Data (January 1, 2016, to August 1, 2022). This retrospective observational cohort study compared patients with stage 3/4 CKD with recurrent hyperkalemia (≥2 hyperkalemia events within 1 year [hyperkalemia event: hyperkalemia diagnosis or potassium [K+]>5 mmol/l]; index was the first hyperkalemia event) with an exact- and propensity score-matched cohort of patients with normokalemia (K+ ≥3.5 to ≤5 mmol/l; random K+ as index) and separately with a matched cohort of patients with nonrecurrent hyperkalemia (1 hyperkalemia event within 1 year; index was hyperkalemia event). Patient characteristics, medication use, HRU, and medical costs were compared between cohorts using standardized mean differences during the 12-month baseline period. All-cause HRU and medical costs during the 12-month follow-up were compared using Wilcoxon rank sum tests for continuous variables and McNemar tests for categorical variables. Substudies of recurrent hyperkalemia vs normokalemia were conducted for patients with Medicare coverage and renin-angiotensin-aldosterone system inhibitor (RAASi) use.

RESULTS

The recurrent hyperkalemia vs normokalemia sample comprised 4,549 matched pairs (Medicare substudy: 3,151; RAASi substudy: 3,535) and the recurrent hyperkalemia vs nonrecurrent hyperkalemia sample comprised 1,599 matched pairs. Baseline characteristics, HRU, and medical costs of the cohorts were similar after matching. During follow-up, patients with recurrent hyperkalemia had a mean of 11.2 more health care encounters (0.5 more inpatient admissions, 0.3 more emergency department visits, and 7.2 more outpatient visits) than patients with normokalemia. Patients with recurrent hyperkalemia also had double the total annual medical costs vs normokalemia ($34,163 vs $15,175; P < 0.001), mainly driven by inpatient costs ($21,250 vs $7,392), which accounted for 62.2% and 48.7% of total costs, respectively. Results were similar in the RAASi and Medicare substudies. Recurrent hyperkalemia was associated with a mean 4.3 more all-cause health care encounters and $14,057 higher medical costs (both P < 0.001) than nonrecurrent hyperkalemia.

CONCLUSIONS

Recurrent hyperkalemia in patients with stage 3/4 CKD was associated with higher all-cause HRU and medical costs compared with normokalemia (including in patients with Medicare coverage and RAASi use) and nonrecurrent hyperkalemia. Research is needed to understand if long-term treatment strategies aimed at preventing hyperkalemia recurrence may alleviate this economic burden.

Management of hyperkalemia: Expert consensus from Kuwait - a Modified Delphi Approach

Introduction

Hyperkalemia is common in heart failure (HF) patients on renin angiotensin aldosterone inhibitors (RAASi), in chronic kidney disease (CKD), and in hemodialysis, and it negatively impacts their management. New potassium binders, such as sodium zirconium cyclosilicate (SZC), are effective in management of acute and chronic hyperkalemia. However, guidelines inconsistencies and lack of standardized treatment protocols are hindering proper and wider use of such agents. Therefore, an expert panel from Kuwait developed a consensus statement to address hyperkalemia management in acute settings, in HF, in CKD, and in hemodialysis.

Methods

A three-step modified Delphi method was adopted to develop the present consensus, which consisted of two rounds of voting and in-between a virtual meeting. Twelve experts from Kuwait participated in this consensus. Statements were developed and shared with experts for voting. A meeting was held to discuss statements that did not reach consensus at the first round and then the remaining statements were shared for final voting.

Results

The consensus consists of 44 statements involving an introduction to and the management of hyperkalemia in acute settings, HF, CKD, and hemodialysis. Thirty-six statements approved unanimously in the first vote. In the second vote, four statements were removed and four were approved after editing.

Conclusion

Hyperkalemia management lacks standardized definitions, treatment thresholds and consistent guidelines and laboratory practices. This consensus is in response to lack of standardized treatment in the Arabian Gulf, and it aims to establish guidance on hyperkalemia management for healthcare practitioners in Kuwait and highlight future needs.

Hyperkalemia Incidence in Patients With Non-Dialysis Chronic Kidney Disease: A Large Retrospective Cohort Study From United States Clinical Care

Rationale & Objective

Estimates of the incidence of hyperkalemia in patients with chronic kidney disease (CKD) vary widely. Our objective was to estimate hyperkalemia incidence in patients with CKD from routine clinical care, including by level of kidney damage or function and among important patient subgroups.

Study Design

Retrospective cohort study.

Setting & Participants

1,771,900 patients with stage 1-4 CKD identified from the US Optum De-Identified electronic health records database.

Exposures or Predictors

Impaired kidney damage or function level at baseline based on urinary albumin-creatinine ratio (UACR) and estimated glomerular filtration rate (eGFR), respectively, and selected patient subgroups.

Outcomes

Hyperkalemia: 2 elevated serum potassium values (≥5.5 mmol/L) from the inpatient setting (2-24 hours apart) or outpatient setting (maximum 7 days apart), or 1 elevated serum potassium value plus pharmacotherapy initiation or hyperkalemia diagnosis (maximum 3 days apart).

Analytical Approach

Incidence rates of hyperkalemia were calculated. Estimates were stratified by UACR and eGFR level at baseline and patient subgroups.

Results

Over a mean follow-up of 3.9 years, the incidence of hyperkalemia was 3.37 events/100 person-years (95% confidence intervals, 3.36-3.38). Higher incidence rates were observed with increased UACR and lower eGFR. Highest rates were observed with UACR ≥3,500 (up to 19.1/100 person-years) irrespective of decreased eGFR level. High rates also occurred in patients with type 2 diabetes mellitus (T2DM, 5.43/100 person-years), heart failure (8.7/100 person-years), and those prescribed steroidal mineralocorticoid receptor antagonists (sMRAs, 7.7/100 person-years).

Limitations

Potential misclassification of variables from possible medical coding errors; potential data incompleteness issues if patients received care at institutions not included in Optum.

Conclusions

Hyperkalemia is a frequent occurrence in CKD, particularly in patients with T2DM, heart failure, or prescribed sMRAs, indicating the need for regular serum potassium and UACR monitoring in this patient population to help mitigate risk.

The Prevalence and Risk Factors of Hyperkalemia in the Outpatient Setting

Background

Hyperkalemia is a life-threatening condition in outpatient and emergency departments. Hyperkalemia is associated with more events of major adverse cardiovascular diseases, hospitalization, and death. The aim of this study is to study and assess the prevalence and risk factors for developing hyperkalemia within the Thai population.

Method

A cross-sectional observational study of 3,299 unique adult patients (≥18 years) in one calendar year (2021) with at least 1 valid serum potassium (SK) test was conducted in the outpatient department of medicine. Hyperkalemia was determined as SK ≥5.8 mmol/L without hemolysis or technical error. Clinical data and laboratory tests were collected for analysis of risk factors.

Result

2,971 patients (131 hyperkalemia and 2,840 control) were eligible. The annual prevalence of hyperkalemia was 4.41%. The mean ages of patients were 66.5 years in the hyperkalemia group and 55.9 years in the control group. Increasing age had a positive association (r = 0.220, p < 0.001) to risk of hyperkalemia, whereas the estimated glomerular filtration rate (eGFR) had an inverse association with SK level (r = -0.398, p < 0.001). The risk factors for hyperkalemia were patients with age ≥65 years (odds ratio, 2.106; 95% CI, 1.399, 3.171; p < 0.001), presence of diabetes mellitus (DM, odds ratio, 1.541; 95% CI, 1.030, 2.306; p = 0.036), chronic kidney disease (CKD) stage ≥3 (odds ratio, 14.885; 95% CI, 8.112, 27.313; p < 0.001), hemodialysis treatment (odds ratio, 10.170; 95% CI, 5.858, 17.657; p < 0.001), and usage of renin-angiotensin-aldosterone system inhibitors (RAASi, odds ratio, 2.256; 95% CI, 1.440, 3.536; p < 0.001).

Conclusion

The risk factors contributing to hyperkalemia were patients with older age, DM, CKD, hemodialysis treatment, and usage of RAASi. Although the usage of RAASi is proven to be a cardiovascular advantage in the elderly, DM, and CKD patients, careful monitoring of SK is strongly advised to optimize patient care.

Efficacy and Safety of Sodium-Glucose Cotransporter-2 Inhibitors in Nondiabetic Patients with Chronic Kidney Disease: A Review of Recent Evidence

Background

Sodium-glucose cotransporter-2 inhibitors (SGLT2i) were initially developed as glucose-lowering agents in patients with type-2 diabetes. However, available data from clinical trials and meta-analyses suggest that SGLT2i have pleiotropic benefits in reducing mortality and delaying the progression of chronic kidney disease (CKD) in both diabetic and nondiabetic patients. Thus, we herein review the current evidence regarding the efficacy and safety of SGLT2i in patients with nondiabetic CKD and appraise the recently reported clinical trials that might facilitate the management of CKD in routine clinical practice.

Summary

The benefits of SGLT2i on nondiabetic CKD are multifactorial and are mediated by a combination of mechanisms. The landmark DAPA-CKD trial revealed that dapagliflozin administered with renin-angiotensin system blockade drugs reduced the risk of a sustained decline (at least 50%) in the estimated glomerular filtration rate, end-stage kidney disease, or death from cardiorenal causes. The recent EMPA-KIDNEY trial showed that empagliflozin therapy led to a lower risk of progression of kidney disease or death from cardiovascular causes. These benefits were consistent in patients with and without diabetes. Moreover, a meta-analysis of DAPA-HF and EMPEROR-Reduced trials confirmed reductions in the combined risk of cardiovascular death or worsening heart failure including composite renal endpoint.

Key Messages

Considering the robust data available from DAPA-CKD, EMPA-KIDNEY, and other trials such as EMPEROR-Preserved, DIAMOND that included nondiabetic patients, it may be necessary to update current guidelines to include SGLT2i as a first-line therapy for CKD and reevaluate current CKD therapeutic approaches.

Hyperkalemia in chronic kidney disease: a focus on potassium lowering pharmacotherapy

INTRODUCTION

Hyperkalemia is one of the most common electrolyte disorders in chronic kidney disease (CKD) and is associated with serious adverse outcomes. Hyperkalemia risk is even greater when CKD patients also have additional predisposing conditions such as diabetes or heart failure. Renin-angiotensin-aldosterone-system blockers are first-line treatments for cardio- and nephroprotection, but their use is often limited due to K+ elevation, resulting in high rates of discontinuation.

AREAS COVERED

This article provides an overview of factors interfering with K+ homeostasis and discusses recent data on newer therapeutic agents used for the treatment of hyperkalemia. A detailed literature search was performed in two major databases (PubMed/MEDLINE and Scopus) up to April 2023.

EXPERT OPINION

Major clinical trials have tested new and promising kidney protective therapies such as sodium/glucose-cotransporter-2 inhibitors and mineralocorticoid-receptor-antagonists, with promising results. Until recently, the only treatment option for hyperkalemia was the cation-exchanging resin sodium-polystyrene-sulfonate. However, despite its common use, the efficacy and safety data of this drug in the long-term management of hyperkalemia are scarce. During the last decade, two novel orally administered K+-exchanging compounds (patiromer and sodium-zirconium-cyclosilicate) have been approved for the treatment of adults with hyperkalemia, as they both effectively reduce elevated serum K+ and maintain chronically K+ balance within the normal range with an excellent tolerability and no serious adverse events.

Early diagnosis of chronic kidney disease in patients with diabetes in France: multidisciplinary expert opinion, prevention value and practical recommendations

Diabetes is the leading cause of end-stage kidney disease (ESKD), accounting for approximately 50% of patients starting dialysis. However, the management of these patients at the stage of chronic kidney disease (CKD) remains poor, with fragmented care pathways among healthcare professionals (HCPs). Diagnosis of CKD and most of its complications is based on laboratory evidence. This article provides an overview of critical laboratory evidence of CKD and their limitations, such as estimated glomerular filtration rate (eGFR), urine albumin-to-creatinine ratio (UACR), Kidney Failure Risk Equation (KFRE), and serum potassium. eGFR is estimated using the CKD-EPI 2009 formula, more relevant in Europe, from the calibrated dosage of plasma creatinine. The estimation formula and the diagnostic thresholds have been the subject of recent controversies. Recent guidelines emphasized the combined equation using both creatinine and cystatin for improved estimation of GFR. UACR on a spot urine sample is a simple method that replaces the collection of 24-hour urine. Albuminuria is the preferred test because of increased sensitivity but proteinuria may be appropriate in some settings as an alternative or in addition to albuminuria testing. KFRE is a new tool to estimate the risk of progression to ESKD. This score is now well validated and may improve the nephrology referral strategy. Plasma or serum potassium is an important parameter to monitor in patients with CKD, especially those on renin-angiotensin-aldosterone system (RAAS) inhibitors or diuretics. Pre-analytical conditions are essential to exclude factitious hyperkalemia. The current concept is to correct hyperkalemia using pharmacological approaches, resins or diuretics to be able to maintain RAAS blockers at the recommended dose and discontinue them at last resort. This paper also suggests expert recommendations to optimize the healthcare pathway and the roles and interactions of the HCPs involved in managing CKD in patients with diabetes.

Influence of SGLT2i and RAASi and Their Combination on Risk of Hyperkalemia in DKD: A Network Meta-Analysis

BACKGROUND

This network meta-analysis investigated the effect of various combined regimens of sodium-glucose cotransporter-2 inhibitors (SGLT2is) and renin-angiotensin-aldosterone system inhibitors (RAASis) on the occurrence of hyperkalemia in diabetic kidney disease.

METHODS

The risk of hyperkalemia was compared using the random-effects model of network meta-analysis, with results expressed as odds ratios (ORs) with 95% confidence intervals (CIs). The comparative effects of all medications and their combinations with placebo were ranked using the surface under the cumulative ranking probabilities.

RESULTS

In total, 27 eligible studies involving 43,589 participants with diabetic kidney disease were included. Major findings showed that the use of mineralocorticoid receptor antagonists (MRAs) on top of angiotensin-converting enzyme inhibitors (ACEIs) or angiotensin receptor blockers (ARBs) prominently increased hyperkalemia incidence when compared with placebo (OR, 6.08; 95% CI, 2.30 to 16.08), ACEI (OR, 3.07; 95% CI, 1.14 to 8.31), ARB (OR, 2.57; 95% CI, 1.10 to 6.02), SGLT2i (OR, 9.22; 95% CI, 2.99 to 28.46), renin inhibitors+ACEI/ARB (OR, 2.23; 95% CI, 1.14 to 4.36), or SGLT2i+ACEI/ARB (OR, 4.10; 95% CI, 2.32 to 7.26). Subgroup analysis among different generations of MRA found that spironolactone had the strongest effect in combination with ACEI/ARB, even higher than the combined use of ACEI and ARB (OR, 2.89; 95% CI, 1.26 to 6.63). In addition, SGLT2i had a significantly lower incidence of hyperkalemia compared with ACEI (OR, 0.33; 95% CI, 0.12 to 0.91), ARB (OR, 0.28; 95% CI, 0.13 to 0.61), dual RAASi (ACEI combined with ARB; OR, 0.17; 95% CI, 0.06 to 0.47), or MRA or renin inhibitors combined with ACEI/ARB (OR, 0.11; 95% CI, 0.04 to 0.33; OR, 0.24; 95% CI, 0.08 to 0.76, respectively). Moreover, adding SGLT2i to the combination of MRA and ACEI/ARB, as well as the combinations of different RAASis, markedly reduced the occurrence of hyperkalemia.

CONCLUSIONS

Among the therapeutic drugs with the potential risk of increasing serum potassium in patients with diabetic kidney disease, MRA added an extra risk of hyperkalemia while SGLT2i had the opposite effect and could even reverse the elevation of serum potassium caused by the combined regimen, including MRAs.

Hyperkalemia in CKD: an overview of available therapeutic strategies

Hyperkalemia (HK) is a life-threatening condition that often occurs in patients with chronic kidney disease (CKD). High serum potassium (sKsK) is responsible for a higher risk of end-stage renal disease, arrhythmias and mortality. This risk increases in patients that discontinue cardio-nephroprotective renin-angiotensin-aldosterone system inhibitor (RAASi) therapy after developing HK. Hence, the management of HK deserves the attention of the clinician in order to optimize the therapeutic strategies of chronic treatment of HK in the CKD patient. The adoption in clinical practice of the new hypokalaemic agents patiromer and sodium zirconium cyclosilicate (SZC) for the prevention and chronic treatment of HK could allow patients, suffering from heart failure and chronic renal failure, to continue to benefit from RAASi therapy. We have updated a narrative review of the clear variables, correct definition, epidemiology, pathogenesis, etiology and classifications for HK among non-dialysis CKD (ND CKD) patients. Furthermore, by describing the prognostic impact on mortality and on the progression of renal damage, we want to outline the strategies currently available for the control of potassium (K+) plasma levels.

Managing Hyperkalemia in the Modern Era: A Case-Based Approach

The last decade has seen tremendous advances in the prevention and treatment of recurrent hyperkalemia. In this narrative review, we aim to highlight contemporary data on key areas in the epidemiology and management of hyperkalemia. Focusing on drug-induced hyperkalemia (the implications of renin-angiotensin-aldosterone system inhibitors [RAASi] discontinuation and the role of mineralocorticoid receptor antagonists), newer concurrent therapies that modify potassium handling (sodium-glucose transporter 2 inhibitors [SGLT2i]), the introduction of new treatment agents (oral potassium binding agents), and the controversial role of dietary potassium restriction, we apply recent research findings and review the evidence in a case-based format.

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.

Discontinuation of Renin-Angiotensin-Aldosterone System Inhibitors Secondary to Hyperkalemia Translates into Higher Cardiorenal Outcomes

INTRODUCTION

Discontinuation of renin-angiotensin-aldosterone system inhibitor (RAASi) is common after hyperkalemia. We evaluated the risk of kidney and mortality outcomes associated with RAASi discontinuation among patients with chronic kidney disease (CKD) and hyperkalemia.

METHODS

We identified adult patients with CKD (eGFR <60 mL/min/1.73 m2) who experienced new-onset hyperkalemia (potassium ≥5.0 mEq/L) between 2016 and 2017 from Kaiser Permanente Southern California and followed them through 2019. We defined treatment discontinuation as having ≥90-day gap in refills of all RAASi within 3 months after hyperkalemia. We used multivariable Cox proportional hazards models to evaluate the association between RAASi discontinuation and the primary composite outcome of kidney (≥40% eGFR decline, dialysis, kidney transplant) or all-cause mortality. We evaluated cardiovascular events and recurrence of hyperkalemia as secondary outcomes.

RESULTS

Among 5,728 patients (mean age 76 years), 13.5% discontinued RAASi within 3 months after new-onset hyperkalemia. During the median 2 years of follow-up, 29.7% had the primary composite outcome (15.5% with ≥40% eGFR decline, 2.8% dialysis or kidney transplant, 18.4% all-cause mortality). Patients who discontinued RAASi had a higher all-cause mortality compared with those who continued RAASi (26.7% vs. 17.1%) but had no differences in kidney outcomes, cardiovascular events, and recurrence of hyperkalemia. RAASi discontinuation was associated with a higher risk of kidney or all-cause mortality composite outcome (adjusted hazard ratio [aHR] 1.21, 95% CI: 1.06, 1.37) mainly driven by all-cause mortality (aHR: 1.34, 95% CI: 1.14, 1.56).

CONCLUSION

RAASi discontinuation after hyperkalemia was associated with worsened mortality, which may underscore the benefits of continuing RAASi among patients with CKD.

A systematic review and meta-analysis of the clinical impact of stopping renin-angiotensin system inhibitor in patients with chronic kidney disease

Although renin-angiotensin system (RAS) inhibitors reduce the risk of cardiovascular diseases and end-stage kidney disease (ESKD) in chronic kidney disease (CKD) patients, they are often discontinued in clinical practice due to drug-related adverse events. However, limited evidence is available about the clinical impact of RAS inhibitor discontinuation in CKD patients. A comprehensive search of publications investigating the effect of discontinuing RAS inhibitors on clinical outcomes in CKD patients in PubMed, the Cochrane Library, and Web of Science was conducted (inception to November 7, 2022), and potentially relevant studies were searched by hand (through November 30, 2022). Two reviewers independently extracted data according to the PRISMA and MOOSE guidelines and assessed the quality of each study with risk-of-bias tools, RoB2 and ROBINS-I. The pooled hazard ratio (HR) for each outcome was integrated with a random-effect model. A total of 1 randomized clinical trial and 6 observational studies involving 248,963 patients were included in the systematic review. The meta-analysis of observational studies showed that discontinuation of RAS inhibitors was associated with a higher risk of all-cause mortality (HR, 1.41 [95% CI, 1.23-1.62]; I² = 97%), ESKD (1.32 [95% CI, 1.10-1.57]; I² = 94%) and MACE (1.20 [95% CI 1.15-1.25]; I² = 38%), but not with hyperkalemia (0.79 [95% CI 0.55-1.15]; I² = 90%). Overall risk of bias was moderate-to-serious, and quality of evidence (GRADE system) was low-to-very low. The present study suggests that CKD patients would benefit from continuing RAS inhibitors.

Real-world evidence for steroidal mineralocorticoid receptor antagonists in patients with chronic kidney disease

Background

Mineralocorticoid receptor antagonists (MRAs) were shown to delay chronic kidney disease (CKD) progression in patients with hypertension and/or heart failure (HF) and proteinuria.

Objective

We conducted a systematic literature review on real-world evidence to identify the literature gaps related to the efficacy and safety outcomes of MRAs administered to CKD patients.

Results

A total of 751 records were identified of which, 23 studies (26 publications) were analyzed. Studies included heterogeneous populations, including the overall CKD, CKD and diabetes, CKD and HF, and CKD and a history of cardiovascular disease. Most of the studies were small and non-rigorous, resulting in a notable lack of evidence in these populations. In the overall CKD population, steroidal MRAs resulted in a significant or sustained eGFR reduction but no efficacy in delaying progression to end-stage kidney disease. No cardiovascular protection was found. Results for all-cause mortality and hospitalization for HF were inconsistent; however, the longest follow-up studies indicate similar or lower incidence for spironolactone non-users. Most results consistently reported a higher incidence of hyperkalemia among patients on steroidal MRAs in all CKD stages, and side effects led to high discontinuation rates in the real-world setting.

Conclusions

Despite the limited availability of evidence on the effectiveness and safety of steroidal MRAs in CKD patients and subgroups with diabetes, HF or history of cardiovascular disease, MRAs were shown to have a limited effect on renal and cardiovascular outcomes. Gaps in the evidence regarding the efficacy and safety of MRAs are particularly relevant in diabetic CKD patients; therefore, further research is warranted.

A Nomogram to Identify Hyperkalemia Risk in Patients with Advanced CKD

Background

Hyperkalemia is a common and life-threatening complication of CKD. We aimed to develop and validate a nomogram that could identify the risk of hyperkalemia (≥5.5 mmol/L) in patients with CKD.

Methods

A retrospective cohort study was performed in adult patients with predialysis advanced CKD (stages ≥3) in 2020-2021 for the outcome of hyperkalemia within 6 months. The training set was used to identify risk factors of hyperkalemia. Then a nomogram was developed by multivariable logistic regression analysis. C-statistics, calibration curves, and decision curve analysis (DCA) were used, and the model was validated in the internal and two external validation sets.

Results

In total, 847 patients with advanced CKD were included. In 6 months, 28% of patients had hyperkalemia (234 out of 847). Independent risk factors were: age ≥75 years, higher CKD stages, previous event of serum potassium ≥5.0 mmol/L within 3 months, and comorbidities with heart failure, diabetes, or metabolic acidosis. Then the nomogram on the basis of the risk factors adding the use of renin-angiotensin-aldosterone system inhibitors was constructed. The C-statistic of the model was 0.76 (95% CI, 0.70 to 0.78), and was stable in both the internal validation set (0.73; 95% CI, 0.63 to 0.82) and external validation sets (0.88; 95% CI, 0.84 to 0.95 and 0.82; 95% CI, 0.72 to 0.92). Calibration curves and DCA analysis both found good performances of the nomogram.

Conclusion

A feasible nomogram and online calculator were developed and validated to evaluate the risk of hyperkalemia within 6 months in patients with advanced CKD. Patients with CKD and a high risk of hyperkalemia may benefit from intensive monitoring and early triage.

Cost-Effectiveness of Treating Patients with Chronic Kidney Disease and Prior Hyperkalemia with Renin-Angiotensin-Aldosterone System Inhibitor and Patiromer: A Swiss Public Healthcare Perspective

INTRODUCTION

Hyperkalemia is associated with increased morbidity and mortality in patients with chronic kidney disease (CKD). Patiromer (Veltassa^®) is an oral potassium binder indicated for the treatment of hyperkalemia in adults. We evaluated the impact of patiromer on the Swiss healthcare resources when used in patients with CKD and hyperkalemia who were on renin-angiotensin-aldosterone system inhibitor (RAASi) treatment.

METHODS

We built a decision tree and calculated the number needed to treat (NNT) to prevent hyperkalemia, hospitalization, and death based on published aggregated data. The decision tree was populated with available data from relevant patiromer clinical trials and data were applied to create a simple model showing the expected effectiveness of adding patiromer to the treatment of patients with medium-to-severe stage CKD on RAASi compared to RAASi only. Adapting the model to the Swiss healthcare system allowed us to estimate the impact of the new treatment on healthcare expenditures from a payer as well as a Swiss public healthcare perspective.

RESULTS

Patiromer reduced the absolute risk for recurrent hyperkalemia by 48% within 8 weeks, resulting in an NNT of 2.1 [95% CI 1.4, 3.7]. If one assumes that 90%, 50%, or 10% of all moderate-to-severe hyperkalemic events lead to hospitalization, the NNT to prevent one hospitalization would be 2.5, 4.4, and 22.2, respectively. On the basis of the death rate of patients with mild or moderate-to-severe hyperkalemia, and the prevalence of mild or moderate-to-severe hyperkalemia in the treatment and control groups, the NNT was 78.7 [95% CI 64.0, 99.3] to prevent one death. Patiromer resulted in expected cost offsets of CHF 303 (1 CHF = 0.95 EUR as of 2022) per patient over 8 weeks in Switzerland.

CONCLUSION

Patiromer used for the treatment of CKD reduces hyperkalemia recurrence leading to improved patient care. This results in substantial offset costs for the Swiss healthcare system.

RAAS Inhibitor Prescription and Hyperkalemia Event in Patients With Chronic Kidney Disease: A Single-Center Retrospective Study

Hyperkalemia is common in patients treated with renin-angiotensin-aldosterone system inhibitors (RAASis), and it represents the main cause of the large gap reported between guideline recommendations and real-world practice in chronic kidney disease (CKD). We conducted a CKD-population-based restrospective study to determine the prevalence of patients with CKD treated with RAASis, incidence of hyperkalemia in patients with CKD treated with RAASis, and proportion of patients with RAASi medication change after experiencing incident hyperkalemia. Among 809 patients with CKD analyzed, 556 (68.7%) were treated with RAASis, and RAASi prescription was greater in stages 2-4 of CKD. Hyperkalemia occurred in 9.2% of RAASi-treated patients, and the adjusted rate of hyperkalemia among patients with stage 4-5 CKD was 3-fold higher compared with patients with eGFR > 60 ml/min/1.73 m2. RAASi treatment was discontinued in 55.3% of the patients after hyperkalemia event (74.2% discontinued therapy, 3.2% received a reduced dose, and 22.6% reduced the number of RAASi drugs). This study shows that the incidence of hyperkalemia is frequently observed in patients with CKD patients with RAASis, and that rates increase with deteriorating levels of kidney function from stages 1 to 3. RAASi medication change following an episode of hyperkalemia occurred in almost half of the patients after experiencing hyperkalemia.

Renoprotective Roles of Curcumin

The use of herb-based therapies is increasing over the past decades. These agents have been reported to provide many beneficial effects in many experimental and clinical studies. Curcumin is one of these agents which has potent pharmacological effects enabling it for the prevent and treatment of many diseases and pathologies such as renal disorders, hyperglycemia, oxidative stress, hypertension, and dyslipidemia. However, the exact molecular mechanisms mediating these renoprotective effects of curcumin are not well established. So, in the current study, we surveyed for possible renoprotective roles of curcumin and concluded how curcumin protects against renal injuries.

Effects of canagliflozin on serum potassium in people with diabetes and chronic kidney disease: the CREDENCE trial

AIMS

Hyperkalaemia is a common complication of type 2 diabetes mellitus (T2DM) and limits the optimal use of agents that block the renin-angiotensin-aldosterone system, particularly in patients with chronic kidney disease (CKD). In patients with CKD, sodium‒glucose cotransporter 2 (SGLT2) inhibitors provide cardiorenal protection, but whether they affect the risk of hyperkalaemia remains uncertain.

METHODS AND RESULTS

The CREDENCE trial randomized 4401 participants with T2DM and CKD to the SGLT2 inhibitor canagliflozin or matching placebo. In this post hoc analysis using an intention-to-treat approach, we assessed the effect of canagliflozin on a composite outcome of time to either investigator-reported hyperkalaemia or the initiation of potassium binders. We also analysed effects on central laboratory-determined hyper- and hypokalaemia (serum potassium ≥6.0 and <3.5 mmol/L, respectively) and change in serum potassium. At baseline, the mean serum potassium in canagliflozin and placebo arms was 4.5 mmol/L; 4395 (99.9%) participants were receiving renin-angiotensin system blockade. The incidence of investigator-reported hyperkalaemia or initiation of potassium binders was lower with canagliflozin than with placebo [occurring in 32.7 vs. 41.9 participants per 1000 patient-years; hazard ratio (HR) 0.78, 95% confidence interval (CI) 0.64-0.95, P = 0.014]. Canagliflozin similarly reduced the incidence of laboratory-determined hyperkalaemia (HR 0.77, 95% CI 0.61-0.98, P = 0.031), with no effect on the risk of hypokalaemia (HR 0.92, 95% CI 0.71-1.20, P = 0.53). The mean serum potassium over time with canagliflozin was similar to that of placebo.

CONCLUSION

Among patients treated with renin-angiotensin-aldosterone system inhibitors, SGLT2 inhibition with canagliflozin may reduce the risk of hyperkalaemia in people with T2DM and CKD without increasing the risk of hypokalaemia.

L-type calcium channel blocker use and proteinuria among children with chronic kidney diseases

BACKGROUND

Hypertension is common among children with chronic kidney disease (CKD), and dihydropyridine calcium channel blockers (dhCCBs) are frequently used as treatment. The impact of dhCCBs on proteinuria in children with CKD is unclear.

METHODS

Data from 722 participants in the Chronic Kidney Disease in Children (CKiD) longitudinal cohort with a median age of 12 years were used to assess the association between dhCCBs and log transformed urine protein/creatinine levels as well as blood pressure control measured at annual visits. Angiotensin-converting enzyme inhibitor (ACEi) and angiotensin receptor blocker (ARB) use was evaluated as an effect measure modifier.

RESULTS

Individuals using dhCCBs had 18.8% higher urine protein/creatinine levels compared to those with no history of dhCCB or ACEi and ARB use. Among individuals using ACEi and ARB therapy concomitantly, dhCCB use was not associated with an increase in proteinuria. Those using dhCCBs had higher systolic and diastolic blood pressures.

CONCLUSIONS

Use of dhCCBs in children with CKD and hypertension is associated with higher levels of proteinuria and was not found to be associated with improved blood pressure control.

Zeolite Composite Nanofiber Mesh for Indoxyl Sulfate Adsorption toward Wearable Blood Purification Devices

A nanofiber mesh was prepared for the adsorption of indoxyl sulfate (IS), a toxin associated with chronic kidney disease. Removing IS is highly demanded for efficient blood purification. The objective of this study is to develop a zeolite composite nanofiber mesh to remove IS efficiently. Eight zeolites with different properties were used for IS adsorption, where a zeolite with a pore size of 7 Å, H+ cations, and a silica to aluminum ratio of 240 mol/mol exhibited the highest adsorption capacity. This was primarily attributed to its suitable silica to aluminum ratio. The zeolites were incorporated in biocompatible poly (ethylene-co-vinyl alcohol) (EVOH) nanofibers, and a zeolite composite nanofiber mesh was successfully fabricated via electrospinning. The nanofiber mesh exhibited an IS adsorption capacity of 107 μg/g, while the adsorption capacity by zeolite increased from 208 μg/g in powder form to 386 μg/g when dispersed in the mesh. This also led to an increase in cell viability from 86% to 96%. These results demonstrated that this zeolite composite nanofiber mesh can be safely and effectively applied in wearable blood purification devices.

Direct healthcare professional communications: A quantitative assessment study

A retrospective observational study evaluated the direct healthcare professional communication (DHPC) letters disseminated by the Saudi Food and Drug Authority (SFDA) and their compliance with the pharmacovigilance guidelines. The study was utilized all DHPC letters available on the SFDA website, which is intended to communicate drug safety information to healthcare professionals (HCPs). Then, the letters were evaluated based on DHPC letter requirements approved in the European Medicines Agency (EMA) pharmacovigilance guidelines. Statistical analyses were conducted utilizing statistical analysis software (SAS^® version 9.4). In June 2020, 169 letters were retrieved from the SFDA website. Most of the letters had the marketing authorization holder's logo (97%) and mentioned the date of letter issuance (98.8%). The most frequently discussed safety issues were hyperkalemia risk associated with combining renin-angiotensin-aldosterone system (RAAS) medications (10.6%) and cardiac risks (9%). Antineoplastic and immunosuppressant classes were associated with a majority of DHPC letters (15% for each category). A significant percentage of DHPC letters (10%) did not mention an agreement statement with SFDA, and 42 letters did not include marketing authorization holders (MAHs) contact information. The qualified persons responsible for pharmacovigilance and medical directors had signed most of the DHPC letters (51% and 46%, respectively). Many letters mentioned the details of reporting information to both SFDA and an MAH (82%). Moreover, 66% of the DHPC letters presented safety information within the 2-page limit. In conclusion, the DHPC letters disseminated by MAHs in Saudi Arabia have an acceptable level of compliance with the guidelines.

The pharmacotherapeutic management of hyperkalemia in patients with cardiovascular disease

Introduction: Patients with cardiovascular diseases (CVD) are at increased risk of hyperkalemia, particularly when treated with renin-angiotensin-aldosterone inhibitors (RAASIs). Because the occurrence or fear of hyperkalemia, RAASIs are frequently down-titrated or discontinued in patients with CVD, with consequent worse outcomes than patients who remain on maximum doses.Areas covered: This article reviews potassium homeostasis, epidemiology, risk factors, and outcomes of hyperkalemia, and efficacy and safety of the drugs used for acute and chronic treatment of hyperkalemia. A literature search was carried out using the PubMed and guidelines for the management of hyperkalemia.Expert opinion: The emergency treatment of hyperkalemia is not supported by high-quality evidence and clinical trials did not report drug effects on clinical outcomes. Two potassium binders, patiromer and sodium zirconium cyclosilicate, represent a new approach in the treatment of chronic hyperkalemia as they may allow the titration and maintenance of guidelines-recommended doses of RAASIs in patients with CVD who otherwise would not tolerate them due to the risk of hyperkalemia.Further studies are needed to evaluate the safety and efficacy of drug therapy and support the development of guidelines for acute and chronic hyperkalemia.

Renin-angiotensin system blockade in patients with chronic kidney disease: benefits, problems in everyday clinical use, and open questions for advanced renal dysfunction

Management of hypertension and albuminuria are considered among the primary goals of treatment to slow the progression of chronic kidney disease (CKD). Renin-angiotensin system (RAS) blockers, i.e., angiotensin-converting enzyme inhibitors (ACEIs) or angiotensin receptor blockers (ARBs) are the main drugs to achieve these goals. Seminal studies have showed that RAS blockers present significant renoprotective effects in CKD patients with very high albuminuria. In post hoc analyses of such trials, these renoprotective effects appeared more robust in patients with more advanced CKD. However, randomized trials specifically addressing whether RAS blockers should be initiated or maintained in patients with advanced CKD are scarce and do not include subjects with normoalbuminuria, thus, many clinicians are unconvinced for the beneficial effects of RAS blockade in these patients. Further, the fear of hyperkalemia or acute renal decline is another factor due to which RAS blockers are usually underprescribed and are easily discontinued in patients with more advanced CKD; i.e., those in Stages 4 and 5. This review summarizes evidence from the literature regarding the use of RAS blockers in patients with advanced CKD.

Effects and Safety of a Novel Oral Potassium-Lowering Drug-Sodium Zirconium Cyclosilicate for the Treatment of Hyperkalemia: a Systematic Review and Meta-Analysis

Background

Oral sodium zirconium cyclosilicate (SZC) is a novel potassium binder capable of achieving a rapid reduction of serum potassium (sK⁺) and maintaining a long-term normokalemia. We undertook a meta-analysis to summarize and evaluate the effects surrounding SZC in patients with hyperkalemia.

Method

We searched data sources from MEDLINE (from 1950 to Sep 2020), EMBASE (from 1970 to Sep 2020), and the Cochrane Library database (from 1950 to Sep 2020) for eligible studies. All randomized controlled trials (RCTs) regarding comparison of therapeutic effects of SZC in hyperkalemia participants were included.

Results

Seven studies, including 1697 patients with hyperkalemia, were analyzed. SZC significantly reduced mean sK⁺ (−0.42 mmol/L; 95% CI: −0.63 to −0.20 mmol/L, p = 0.0001) compared with placebo, with a significantly greater proportion of patients with normokalemia (RR 3.48, 95% CI 1.49 to 8.11, p = 0.004). Subgroup analyses showed that the longer durations of SZC treatment, the greater magnitudes of potassium reduction when compared with those of placebo (p between subgroups = 0.01) at correction phase. Besides, it also demonstrated sK⁺ tended to decrease more in patients who got longer treatment or larger dosage of SZC at maintenance phase; however, the difference did not reach statistical significance. Additionally, the drug was equally effective in studies with larger than 50% of patients with chronic kidney disease (CKD) or diabetes or patients using renin-angiotensin aldosterone system inhibitor (RAAS) inhibitors (all p < 0.05). The risk of edema (4.30, 1.17 to 15.84; p = 0.03) in SZC group was higher than those of placebo group. No statistically significant differences in the risks of other adverse events were observed between the two groups.

Conclusions

SZC effectively decreased the sK⁺ level in patients with hyperkalemia within 48 h and had benefits in the long-term control of serum potassium in patients who continued to receive SZC with a favorable safety profile from available data.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10557-020-07134-2.

Serum potassium in chronic kidney disease: prevalence, patient characteristics and clinical outcomes

BACKGROUND & AIMS

Abnormalities in serum potassium are a well-known complication of chronic kidney disease (CKD), but little is known about their impact on inpatient outcomes. To better understand the role of dyskalaemia in hospital in-patients, we assessed the epidemiology of potassium disorders among CKD patients, and the association between admission potassium and inpatient mortality or intensive care unit (ICU) requirement.

METHODS

This retrospective hospital-based cohort study (n = 11 156) included patients with eGFR<60 mL/min/1.73m² admitted to Austin Health between 2014 and 2018 and who had an admission potassium value. Dialysis patients or those with a renal transplant were excluded. Multivariate logistic analysis was conducted to identify factors associated with hyperkalaemia (≥5.5 mmol/L) and hypokalaemia (<3.5 mmol/L). Odds ratios for inpatient mortality and ICU admission between potassium categories were obtained by multivariate regression with adjustments for demographics, renal function and comorbidities.

RESULTS

Hyperkalaemia and hypokalaemia were present in 6.86% and 2.94% of hospital admissions, respectively. In multivariate regression male sex, lower eGFR, diabetes and cardiac failure were associated with higher odds of hyperkalaemia. Thiazide diuretics, loop diuretics, infectious disease and endocrine pathology were associated with higher odds of hypokalaemia. A U-shaped association was noted between potassium and inpatient mortality. Potassium <4.0 mmol/L and ≥ 5.0 mmol/L was associated with increased mortality. Only patients with potassium ≥5.5 mmol/L had increased ICU admission risk.

CONCLUSION

Derangements in potassium frequently occur in CKD inpatients and are independently associated with higher mortality and ICU requirement. Further studies are required to determine whether interventions to maintain normokalaemia improve outcomes in this population. This article is protected by copyright. All rights reserved.

Chronic kidney disease in Spain: analysis of patient characteristics, incidence and direct medical costs (2011-2017)

OBJECTIVES

To review the characteristics of patients with chronic kidney disease (CKD) who attended primary and specialized care centers in Spain, and to analyze patients' use of medical resources and direct medical costs of specialized care.

METHODS

Records of patients with CKD admitted to primary and specialized healthcare centers in Spain between 2011 and 2017 from two national discharge databases were analyzed in a retrospective multicenter observational study. Records were classified into one-to-five CKD stages plus a 5b stage, indicating end-stage renal disease.

RESULTS

Most of the patients registered in hospital settings were in stage 5. Registered secondary conditions included hypertensive chronic kidney, diabetes, anemia, hypercholesterolemia, and hypertension. The number of cases registered in primary care settings increased over time, whereas in specialized care centers incidence decreased; hospital incidence of CKD in 2017 was 10.72 per 10,000 persons. Mean in-hospital mortality was 5.90%, which remained stable during the study period. Mortality was associated with respiratory and heart failure. Mean length of hospital stay was 8.19 days, decreasing over the study period, whilst increasing with CKD progression. Mean annual direct medical cost of specialized care was €10,436 per patient. Complications of a transplant and bacterial infections were responsible for major increases in medical costs, that otherwise decreased over the study period.

CONCLUSIONS

The costs of specialized care decreased with the length of hospital stay reduction. Cardiovascular risk factors were crucial in in-hospital mortality. This study provides population-based data to assist decision-makers at the national level and to contribute to worldwide evaluations and disease surveillance.

Impact of Dietary Potassium Restrictions in CKD on Clinical Outcomes: Benefits of a Plant-Based Diet

In patients with advanced-stage chronic kidney disease (CKD), progressive kidney function decline leads to increased risk for hyperkalemia (serum potassium > 5.0 or >5.5 mEq/L). Medications such as renin-angiotensin-aldosterone system inhibitors pose an additional hyperkalemia risk, especially in patients with CKD. When hyperkalemia develops, clinicians often recommend a diet that is lower in potassium content. This review discusses the barriers to adherence to a low-potassium diet and the impact of dietary restrictions on adverse clinical outcomes. Accumulating evidence indicates that a diet that incorporates potassium-rich foods has multiple health benefits, which may also be attributable to the other vitamin, mineral, and fiber content of potassium-rich foods. These benefits include blood pressure reductions and reduced risks for cardiovascular disease and stroke. High-potassium foods may also prevent CKD progression and reduce mortality risk in patients with CKD. Adjunctive treatment with the newer potassium-binding agents, patiromer and sodium zirconium cyclosilicate, may allow for optimal renin-angiotensin-aldosterone system inhibitor therapy in patients with CKD and hyperkalemia, potentially making it possible for patients with CKD and hyperkalemia to liberalize their diet. This may allow them the health benefits of a high-potassium diet without the increased risk for hyperkalemia, although further studies are needed.

Cost-analysis of persistent hyperkalaemia in non-dialysis chronic kidney disease patients under nephrology care in Italy

AIM

In patients with chronic kidney disease (CKD), hyperkalaemia (HK) (potassium level ≥ 5.0 mEq/L) is associated with poor clinical outcomes. This study provides novel insights by comparing management costs of CKD patients with normokalaemia vs those with persistent HK regularly followed in renal clinics in Italy.

METHODS

To this aim, a Markov model over life-time horizon was developed. Time to end-stage renal disease (ESRD) and time to death in CKD patients were derived from an observational multi-centre database including 1665 patients with non-dialysis CKD stage 1-5 under nephrology care in Italy (15 years follow-up). Resource use for CKD and HK management was obtained from the observational database, KDIGO international guidelines, and clinical expert opinion.

RESULTS

Results showed that patients with normokalaemia vs persistent HK brought an average per patient lifetime cost-saving of €16 059 besides delayed onset of ESRD by 2.29 years and increased survival by 1.79 years with increment in total survival and dialysis-free survival in normokalaemia that decreased from early to advanced disease. Cost-saving related to normokalaemia increased at more advanced CKD; however, it was already evident at early stage (3388.97€ at stage 1-3a). OWSA confirmed cost-saving associated with normokalaemia across all parameter variations.

DISCUSSION AND CONCLUSION

This model is the first to simulate the impact of HK in non-dialysis CKD patients on economic and clinical outcomes using real-world data from nephrology clinics. In these patients, persistent HK results into higher lifetime costs, besides poorer clinical outcomes, that are evident since the early stages of CKD. Maintaining normokalaemia should therefore be of main concern in CKD treatment planning to improve long-term economic and clinical outcomes.

Tailoring treatment of hyperkalemia

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.