Pharmacological interventions for the acute management of hyperkalaemia in adults

Comparison of Sodium Zirconium Cyclosilicate to Calcium Polystyrene Sulfonate for Acute Hyperkalemia Among Hospitalized Elderly Patients

Background Our aim was to investigate the effect of sodium zirconium cyclosilicate (SZC) on acute hyperkalemia in hospitalized elderly patients. Methods A retrospective observational study was conducted. All consecutive patients aged 65 years or older who were hospitalized in our hospital between January 2020 and September 2023 were screened. Patients with serum potassium greater than 5.0 mEq/L and those who were prescribed either SZC or calcium polystyrene sulfonate (CPS) during hospitalization were included. The primary outcome was the change in serum potassium within 24 hours from baseline. Patients who were prescribed SZC and those who were prescribed CPS were compared by the Mann-Whitney test. Results A total of 87 hospitalized elderly patients with acute hyperkalemia were included. The median age of the patients was 81 years (IQR 75 to 86); 64 (73.6%) were men, and 64 (73.6%) had chronic kidney disease. The median serum potassium concentration was 6.0 mEq/L (IQR 5.7 to 6.4). Of those, 53 patients received SZC, and 35 patients received CPS. While SZC reduced the serum potassium concentration from 6.1 mEq/L to 5.0 mEq/L, CPS reduced the potassium concentration from 5.9 mEq/L to 5.3 mEq/L within 24 hours. Compared with CPS, SZC significantly reduced potassium (p = 0.003). Conclusions Compared with CPS, SZC might reduce serum potassium more among hospitalized elderly patients with hyperkalemia. Further studies are warranted to determine the role of SZC for acute hyperkalemia in acute care settings.

Disorders of potassium homeostasis after kidney transplantation

Disturbances of potassium balance are often encountered when managing kidney transplant recipients (KTR). Both hyperkalemia and hypokalemia may present either as medical emergencies or chronic outpatient abnormalities. Despite the high incidence of hyperkalemia and its potential life-threatening implications, consensus on its management in KTR is lacking. Hypokalemia in KTR is also well-described, although it is given less attention by clinicians compared to hyperkalemia. This article discusses the etiology, pathophysiology and management of both types of potassium disorders in KTR. Once any emergent situation has been corrected, treatment approaches include correcting insulin deficiency if present, adjusting non-immunosuppressive and immunosuppressive medications, eliminating or supplementing potassium as needed, and dietary counselling. Although commonly of multifactorial etiology, ascertaining the specific cause in a particular patient will help guide successful management. Monitoring KTR through regular laboratory testing is essential to detect serious disturbances in potassium balance since patients are often asymptomatic.

The burden of hyperkalaemia on hospital healthcare resources

Hyperkalaemia is associated with prolonged hospital admission and worse mortality. Hyperkalaemia may also necessitate clinical consults, therapies for hyperkalaemia and high-dependency bed utilisation. We evaluated the 'hidden' human and organisational resource utilisation for hyperkalaemia in hospitalised patients. This was a single-centre, observational cohort study (Jan 2017-Dec 2020) at a tertiary-care hospital. The CogStack system (data processing and analytics platform) was used to search unstructured and structured data from individual patient records. Association between potassium and death was modelled using cubic spline regression, adjusted for age, sex, and comorbidities. Cox proportional hazards estimated the hazard of death compared with normokalaemia (3.5-5.0 mmol/l). 129,172 patients had potassium measurements in the emergency department. Incidence of hyperkalaemia was 85.7 per 1000. There were 49,011 emergency admissions. Potassium > 6.5 mmol/L had 3.9-fold worse in-hospital mortality than normokalaemia. Chronic kidney disease was present in 21% with potassium 5-5.5 mmol/L and 54% with potassium > 6.5 mmol/L. For diabetes, it was 20% and 32%, respectively. Of those with potassium > 6.5 mmol/L, 29% had nephrology review, and 13% critical care review; in this group 22% transferred to renal wards and 8% to the critical care unit. Dialysis was used in 39% of those with peak potassium > 6.5 mmol/L. Admission hyperkalaemia and hypokalaemia were independently associated with reduced likelihood of hospital discharge. Hyperkalaemia is associated with greater in-hospital mortality and reduced likelihood of hospital discharge. It necessitated significant utilisation of nephrology and critical care consultations and greater likelihood of patient transfer to renal and critical care.

Consensus statement on the management of hyperkalaemia-An Asia-Pacific perspective

Hyperkalaemia is an electrolyte imbalance that impairs muscle function and myocardial excitability, and can potentially lead to fatal arrhythmias and sudden cardiac death. The prevalence of hyperkalaemia is estimated to be 6%-7% worldwide and 7%-10% in Asia. Hyperkalaemia frequently affects patients with chronic kidney disease, heart failure, and diabetes mellitus, particularly those receiving treatment with renin-angiotensin-aldosterone system (RAAS) inhibitors. Both hyperkalaemia and interruption of RAAS inhibitor therapy are associated with increased risks for cardiovascular events, hospitalisations, and death, highlighting a clinical dilemma in high-risk patients. Conventional potassium-binding resins are widely used for the treatment of hyperkalaemia; however, caveats such as the unpalatable taste and the risk of gastrointestinal side effects limit their chronic use. Recent evidence suggests that, with a rapid onset of action and improved gastrointestinal tolerability, novel oral potassium binders (e.g., patiromer and sodium zirconium cyclosilicate) are alternative treatment options for both acute and chronic hyperkalaemia. To optimise the care for patients with hyperkalaemia in the Asia-Pacific region, a multidisciplinary expert panel was convened to review published literature, share clinical experiences, and ultimately formulate 25 consensus statements, covering three clinical areas: (i) risk factors of hyperkalaemia and risk stratification in susceptible patients; (ii) prevention of hyperkalaemia for at-risk individuals; and (iii) correction of hyperkalaemia for at-risk individuals with cardiorenal disease. These statements were expected to serve as useful guidance in the management of hyperkalaemia for health care providers in the region.

Asthma and COPD: A Focus on β-Agonists - Past, Present and Future

Asthma has been recognised as a respiratory disorder for millennia and the focus of targeted drug development for the last 120 years. Asthma is one of the most common chronic non-communicable diseases worldwide. Chronic obstructive pulmonary disease (COPD), a leading cause of morbidity and mortality worldwide, is caused by exposure to tobacco smoke and other noxious particles and exerts a substantial economic and social burden. This chapter reviews the development of the treatments of asthma and COPD particularly focussing on the β-agonists, from the isolation of adrenaline, through the development of generations of short- and long-acting β-agonists. It reviews asthma death epidemics, considers the intrinsic efficacy of clinical compounds, and charts the improvement in selectivity and duration of action that has led to our current medications. Important β2-agonist compounds no longer used are considered, including some with additional properties, and how the different pharmacological properties of current β2-agonists underpin their different places in treatment guidelines. Finally, it concludes with a look forward to future developments that could improve the β-agonists still further, including extending their availability to areas of the world with less readily accessible healthcare.

Acute Hyperkalemia Management in the Emergency Department

Acute hyperkalemia is characterized by high concentrations of potassium in the blood that can potentially lead to life-threatening arrhythmias that require emergent treatment. Therapy involves the utilization of a constellation of different agents, all targeting different goals of care. The first, and most important step in the treatment of severe hyperkalemia with electrocardiographic (ECG) changes, is to stabilize the myocardium with calcium in order to resolve or mitigate the development of arrythmias. Next, it is vital to target the underlying etiology of any ECG changes by redistributing potassium from the extracellular space with the use of intravenous regular insulin and inhaled beta-2 agonists. Finally, the focus should shift to the elimination of excess potassium from the body through the use of intravenous furosemide, oral potassium-binding agents, or renal replacement therapy. Multiple nuances and controversies exist with these therapies, and it is important to have a robust understanding of the underlying support and recommendations for each of these agents to ensure optimal efficacy and minimize the potential for adverse effects and medication errors.

Hyperkalaemia and potassium binders: Retrospective observational analysis looking at the efficacy and cost effectiveness of calcium polystyrene sulfonate and sodium zirconium cyclosilicate

WHAT IS KNOWN AND OBJECTIVE

Hyperkalaemia is a common medical emergency in patients admitted to hospital. There is a limited evidence base supporting some of the commonly applied treatment strategies. Although, NICE has recommended the use of sodium zirconium cyclosilicate (SZC) (TA599) and patiromer (TA623) in both acute and chronic hyperkalaemia, there is a limited evidence base for their use in acute hyperkalaemia in the hospital setting, particularly when compared to the present standard of care calcium polystyrene sulfonate (CPS).

METHODS

A retrospective review of the electronic patient record system across our hospital over a 6-month period identified 138 patients who received either SZC (65 patients) or CPS (73 patients) to manage hyperkalaemia, investigating their efficacy and cost effectiveness. Results were analysed using simple descriptive statistics. Based on the results a naïve cost comparison between the two drugs was made.

RESULTS AND DISCUSSION

CPS and SZC both effectively reduced plasm potassium concentrations in patients with hyperkalaemia (6.07 and 6.03 mmol/L respectively) by 1.17 mmol/L and 1.24 mmol/L taking a similar amount of time to work (2.97 days vs. 3 days). The principle causes of hyperkalaemia identified were acute kidney injury, medication, and chronic kidney disease. Cost comparison analysis which took into account raw product price and time needed to dispense medications revealed that CPS has slightly better cost effectiveness compared to SZC albeit at a cost of increased staff input.

WHAT IS NEW AND CONCLUSION

Both CPS and SZC were equally effective at lowering acutely raised potassium concentrations. The cost difference between the two products appears to be small. Claims regarding the benefits of newer agents over older established medications need to be properly explored in randomized trials rather than being based on small scale non-comparative studies.

Treatment strategies for hyperkalemia secondary to urethral obstruction in 50 male cats: 2002-2017

OBJECTIVES

The aims of this study were: to describe the potassium-lowering treatment strategies used to manage moderate-to-severe hyperkalemia in male cats with urethral obstruction (UO); to determine how much dextrose was required per unit of insulin to prevent hypoglycemia; to determine whether early initiation of a dextrose continuous rate infusion (CRI) prevented hypoglycemia; and to determine whether in-hospital mortality was associated with presenting plasma potassium concentration ([K+]).

METHODS

The medical records of male cats presenting with a [K+] ⩾7.0 mEq/l due to UO that had another [K+] measured within 6 h were reviewed retrospectively. All [K+] values within the first 6 h, blood glucose concentrations, treatments for hyperkalemia and survival to discharge were recorded. Analyses were performed to test for associations between dextrose:insulin ratios or method of dextrose administration and the development of hypoglycemia; and for presenting [K+] and mortality. Normally distributed groups of continuous data were compared with a t-test and categorical data were compared with a Fisher's exact test.

RESULTS

Fifty cats were included. Mean presenting [K+] was 8.9 ± 1.0 mEq/l, while the mean final [K+] within 6 h was 6.6 ± 1.4 mEq/l. Forty-two (84%) cats were treated with intravenous fluids and 40 (80%) were treated with dextrose and insulin. Median dextrose:insulin ratio was 2 g/u (range 0.4-100). No dextrose:insulin ratio was found to protect against hypoglycemia, and 3/8 cats that became hypoglycemic had received ⩾2 g dextrose per unit of insulin. There was no association between the early initiation of a dextrose-containing CRI and avoidance of hypoglycemia. No association was found between presenting [K+] and mortality.

CONCLUSIONS AND RELEVANCE

While no specific dextrose:insulin ratio was found to protect against hypoglycemia, there is evidence that the commonly recommended dextrose:insulin ratio of 2 g/u may be inadequate in preventing hypoglycemia in every cat. Severity of hyperkalemia was not associated with mortality.

Hypoglycaemia due to insulin therapy for the management of hyperkalaemia in hospitalised adults: A scoping review

INTRODUCTION

Hyperkalaemia is a very common electrolyte disorder encountered in hospitalised patients. Although hypoglycaemia is a frequent complication of insulin therapy, it is often under-appreciated. We conducted a scoping review of this important complication, and of other adverse effects, of the treatment of hyperkalaemia in hospitalised adults to map existing research on this topic and to identify any knowledge gaps.

MATERIALS AND METHODS

We followed the PRISMA-ScR guidelines. Studies were eligible for inclusion if they reported on any adverse effects in hospitalised patients ≥18-years-old, with hyperkalaemia receiving treatment that included insulin. All eligible research from 1980 to 12 October 2021 were included. We searched Medline (PubMed), Embase (Ovid), the Cochrane Library, CINHAL, Africa-Wide Information, Web of Science Core Collection, LILACS and Epistemonikos. The protocol was prospectively registered with the Open Science Framework (https://osf.io/x8cs9).

RESULTS

Sixty-two articles were included. The prevalence of hypoglycaemia by any definition was 17.2% (95% CI 16.6-17.8%). The median timing of hypoglycaemia was 124 minutes after insulin administration (IQR 102-168 minutes). There were no differences in the prevalence of hypoglycaemia when comparing insulin dose (<10 units vs. ≥10 units), rate of insulin administration (continuous vs. bolus), type of insulin (regular vs. short-acting) or timing of insulin administration relative to dextrose. However, lower insulin doses were associated with a reduced prevalence of severe hypoglycaemia (3.5% vs. 5.9%, P = 0.02). There was no difference regarding prevalence of hypoglycaemia by dextrose dose (≤25 g vs. >25 g); however, prevalence was lower when dextrose was administered as a continuous infusion compared with bolus administration (3.3% vs. 19.5%, P = 0.02). The most common predictor of hypoglycaemia was the pre-treatment serum glucose concentration (n = 13 studies), which ranged from < 5.6-7.8 mmol/L.

CONCLUSION

This is the first comprehensive review of the adverse effects following insulin therapy for hyperkalaemia. Hypoglycaemia remains a common adverse effect in hospitalised adults. Future randomised trials should focus on identifying the optimal regimen of insulin therapy to mitigate the risk of hypoglycaemia.

Observational study of the relative efficacy of insulin-glucose treatment for hyperkalaemia in patients with liver cirrhosis

OBJECTIVES

To determine if liver cirrhosis is associated with reduced efficacy of insulin-glucose treatment in moderate to severe hyperkalaemia.

DESIGN

Retrospective, cohort study.

SETTING

Two secondary and one tertiary care hospital at a large metropolitan healthcare network in Melbourne, Australia.

PARTICIPANTS

This study included 463 adults with a mean age of 68.7±15.8 years, comprising 79 patients with cirrhosis and 384 without cirrhosis as controls, who received standard insulin-glucose treatment for a serum potassium ≥6.0 mmol/L from October 2016 to March 2020. Patients were excluded if they received an insulin infusion, or if there was inadequate follow-up data for at least 6 hours after IDT due to death, lost to follow-up or inadequate biochemistry monitoring. The mean Model for End-stage Liver Disease score in patients with cirrhosis was 22.2±7.5, and the distribution of the Child-Pugh score for cirrhosis was: class A (24%), class B (46%), class C (30%).

OUTCOME MEASURES

The primary outcome was the degree of potassium lowering and the secondary outcome was the proportion of patients who achieved normokalaemia, within 6 hours of treatment.

RESULTS

The mean pretreatment potassium for the cohort was 6.57±0.52 mmol/L. After insulin-glucose treatment, mean potassium lowering was 0.84±0.58 mmol/L in patients with cirrhosis compared with 1.33±0.75 mmol/L for controls (p<0.001). The proportion of patients achieving normokalaemia was 33% for patients with cirrhosis, compared with 53% for controls (p=0.001). By multivariable regression, on average, liver cirrhosis was associated with a reduced potassium lowering effect of 0.42 mmol/L (95% CI 0.22 to 0.63 mmol/L, p<0.001) from insulin-glucose treatment, after adjusting for age, serum creatinine, cancer, pretreatment potassium level, β-blocker use and cotreatments (sodium polystyrene sulfonate, salbutamol, sodium bicarbonate).

CONCLUSIONS

Our observational data suggest reduced efficacy of insulin-glucose treatment for hyperkalaemia in patients with cirrhosis.

An Evidence-Based Narrative Review of the Emergency Department Management of Acute Hyperkalemia

BACKGROUND

The normal range for potassium is within narrow limits. Hyperkalemia is an electrolyte disorder that frequently affects patients in the emergency department (ED), and can result in significant morbidity and mortality if not identified and treated rapidly.

OBJECTIVE

This article provides an evidence-based narrative review of the management of hyperkalemia, with focused updates for the emergency clinician.

METHODS

We searched in MEDLINE, EMBASE, Web of Science, and Scopus databases for articles in English published in peer-reviewed journals and indexed up until May 2020. We used multiple search terms, including hyperkalemia, potassium, acute hyperkalemia, emergency department, dyskalemia, potassium disorders, kidney disease, epidemiology, electrolyte disturbance, severe hyperkalemia, and emergency management.

DISCUSSION

In the ED, interventions aimed to protect patients from the immediate dangers of elevated serum potassium are divided into the following: stabilizing cardiac membrane potentials, reducing serum potassium levels through shift from the extracellular fluid to intracellular fluid, and elimination of potassium through excretion via urinary or fecal excretion. Calcium is widely recommended to stabilize the myocardial cell membrane, but additional research is necessary to establish criteria for use, dosages, and preferred solutions. Redistribution of potassium ions from the bloodstream into the cells is based on intravenous insulin or nebulized β2-agonists.

CONCLUSIONS

Hyperkalemia is a frequent electrolyte disorder in the ED. Because of the risk of fatal dysrhythmia due to cardiac membrane instability, hyperkalemia is a medical emergency. There is a lack of scientific evidence on the optimal management of hyperkalemia and more research is needed to establish optimal strategies to manage acute hyperkalemia in the emergency department.

The Effect of Patient Factors and Cotreatments on the Magnitude of Potassium Lowering with Insulin-Glucose Treatment in Patients with Hyperkalemia

The management of hyperkalemia with insulin-glucose/dextrose treatment (IDT) may be influenced by patient factors and cotreatments. We aimed to determine the magnitude of potassium lowering by IDT while considering patient factors and cotreatments. We observed the change in serum potassium in 410 patients with a mean serum potassium of 6.6 mmol/L (SD, 0.6 mmol/L) treated with IDT at three major metropolitan hospitals. Mean potassium lowering was 1.4 mmol/L (SD, 0.8 mmol/L) and 53% achieved normokalemia. Cotreatment with sodium polystyrene sulfonate, salbutamol, or sodium bicarbonate occurred in 64%, 12%, and 10% of patients, respectively. In multiple linear regression analysis, cotreatment with sodium polystyrene sulfonate or sodium bicarbonate was not associated with any significant reduction in serum potassium beyond that achieved by IDT, within the initial 6 h of treatment. We observed an additional lowering of serum potassium with salbutamol of 0.3 mmol/L (95% CI: 0.1 to 0.6 mmol/L; p = 0.009) but the clinical significance was unclear as the proportion of patients achieving normokalemia was not affected by cotreatment within the initial 6 h after IDT. We also found evidence that the potassium-lowering effect of IDT was dependent on the pre-treatment serum potassium. For every 1 mmol/L increase in pre-treatment serum potassium over 6.0 mmol/L, there was an associated 0.7 mmol/L increase in the potassium-lowering effect of IDT, on average, which was independent of any cotreatment. There was no significant impact of acute kidney injury or chronic kidney disease status on the efficacy of IDT.

Insulin glucose infusion versus nebulised salbutamol versus combination of salbutamol and insulin glucose in acute hyperkalaemia in the emergency room: protocol for a randomised, multicentre, controlled study (INSAKA)

INTRODUCTION

Hyperkalaemia is a common electrolyte disorder and can be life-threatening. In the emergency room (ER), interventions aim to protect patients from the immediate dangers of elevated serum potassium by redistributing potassium ions from the bloodstream into the cells via intravenous insulin or nebulised beta2-agonists. However, to date, evidence for acute management of hyperkalaemia is limited. The aim of this randomised controlled trial is therefore to compare three strategies, namely insulin/glucose intravenous infusion, nebulised salbutamol or a combination of nebulised salbutamol and insulin/glucose intravenous infusion to reduce serum potassium concentration at 60 min as a first-line treatment in patients admitted to the ER with serum potassium concentrations superior or equal to 6 mmol/L.

METHODS AND ANALYSIS

INSAKA is a prospective, multicentre, controlled, open-label, parallel-group, randomised in a 1:1:1 ratio clinical trial. Patients will be eligible for randomisation if they have serum potassium concentrations superior or equal to 6 mmol/L measured in the ER. Patients will receive either: (1) 10 mg of nebulised salbutamol, (2) 10 units of short-acting insulin in an intravenous bolus with 500 mL of 10% glucose or (3) 10 units of short-acting insulin in an intravenous bolus with 500 mL of 10% glucose combined with 10 mg of nebulised salbutamol. The primary endpoint will be the mean change in the absolute serum potassium level from baseline to 60 min measured in mmol/L. We plan to include 525 patients.

ETHICS AND DISSEMINATION

The INSAKA trial will be conducted in accordance with the International Council on Harmonization Good Clinical Practices. All trial documents and procedures have been reviewed and approved by the Ethics Committee Sud Méditerranée III (approval ID number: 19.07.16.36428). The results will be actively disseminated through peer-reviewed journals, conference presentations, social media, broadcast media, print media and the internet.

TRIAL REGISTRATION

EudraCT number: 2019-002710-39, Clinicaltrials.gov identifier: NCT04012138.

New Treatment Options for Hyperkalemia in Patients with Chronic Kidney Disease

Hyperkalemia may cause life-threatening cardiac and neuromuscular alterations, and it is associated with high mortality rates. Its treatment includes a multifaceted approach, guided by potassium levels and clinical presentation. In general, treatment of hyperkalemia may be directed towards stabilizing cell membrane potential, promoting transcellular potassium shift and lowering total K+ body content. The latter can be obtained by dialysis, or by increasing potassium elimination by urine or the gastrointestinal tract. Until recently, the only therapeutic option for increasing fecal K+ excretion was represented by the cation-exchanging resin sodium polystyrene sulfonate. However, despite its common use, the efficacy of this drug has been poorly studied in controlled studies, and concerns about its safety have been reported. Interestingly, new drugs, namely patiromer and sodium zirconium cyclosilicate, have been developed to treat hyperkalemia by increasing gastrointestinal potassium elimination. These medications have proved their efficacy and safety in large clinical trials, involving subjects at high risk of hyperkalemia, such as patients with heart failure and chronic kidney disease. In this review, we discuss the mechanisms of action and the updated data of patiromer and sodium zirconium cyclosilicate, considering that the availability of these new treatment options offers the possibility of improving the management of both acute and chronic hyperkalemia.

Potassium binders for chronic hyperkalaemia in people with chronic kidney disease

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; I2 = 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; I2 = 0%; low certainty evidence), diarrhoea (5 studies, 720 participants: RR 0.84, 95% CI 0.47, 1.48; I2 = 0%; low certainty evidence), and vomiting (2 studies, 122 participants: RR 1.72, 95% CI 0.35 to 8.51; I2 = 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; I2 = 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; I2 = 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; I2 = 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; I2 = 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.

Evidence in support of hyperkalaemia management strategies: A systematic literature review

BACKGROUND

Hyperkalaemia is a potentially life-threatening condition that can be managed with pharmacological and non-pharmacological approaches. With the recent development of new hyperkalaemia treatments, new information on safe and effective management of hyperkalaemia has emerged.

OBJECTIVES

This systematic literature review (SLR) aimed to identify all relevant comparative and non-comparative clinical data on management of hyperkalaemia in adults. Our secondary aim was to assess the feasibility of quantitatively comparing randomised controlled trial (RCT) data on the novel treatment sodium zirconium cyclosilicate (ZS) and established pharmacological treatments for the non-emergency management of hyperkalaemia, such as the cation-exchangers sodium/calcium polystyrene sulphonate (SPS/CPS).

METHODS

MEDLINE, Embase and the Cochrane Library were searched on 3^rd April 2017, with additional hand-searches of key congresses and previous SLRs. Articles were screened by two independent reviewers. Eligible records reported interventional or observational studies of pharmacological or non-pharmacological management of hyperkalaemia in adults.

RESULTS

Database searches identified 2,073 unique records. Two hundred and one publications were included, reporting 30 RCTs, 29 interventional non-RCTs and 43 observational studies. Interventions investigated in RCTs included ZS (3), SPS/CPS (3), patiromer (4) and combinations of temporising agents (6 RCTs). A robust and meaningful indirect treatment comparison between ZS and long-established cation-binding agents (SPS/CPS) was infeasible because of heterogeneity between studies (including time points and dosing) and small sample size in SPS/CPS studies.

CONCLUSIONS

Despite hyperkalaemia being associated with several chronic diseases, there is a paucity of high-quality randomised evidence on long-established treatment options (SPS and CPS) and a limited evidence base for hyperkalaemia management with these agents.