Incidence of and risk factors for newly diagnosed hyperkalemia after hospital discharge in non-dialysis-dependent CKD patients treated with RAS inhibitors

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.

Efficacy of renin-angiotensin system inhibitors, calcium channel blockers, and diuretics in hypertensive patients with diabetes: subgroup analysis based on albuminuria in a systematic review and meta-analysis

In hypertensive patients with diabetes, the effectiveness of renin-angiotensin system (RAS) inhibitors in improving mortality, cardiovascular events, and renal outcomes, compared to other antihypertensive drugs such as calcium channel blockers (CCBs) and diuretics, remains uncertain, particularly in the context of albuminuria. A comprehensive literature search was conducted using PubMed, the Cochrane Library, and the Japan Medical Abstracts Society databases up to October 2024. A meta-analysis of 12 randomized controlled trials, including 14,163 patients, was performed. RAS inhibitors showed no significant advantage over CCBs or diuretics for all-cause mortality (relative risk [RR]: 1.00, 95% confidence interval [CI]: 0.92-1.08, p = 0.98), myocardial infarction (RR: 0.64, 95% CI: 0.32-1.31, p = 0.22), stroke (RR: 1.14, 95% CI: 1.00-1.31, p = 0.05), composite cardiovascular events (RR: 0.93, 95% CI: 0.81-1.07, p = 0.45), or end-stage renal disease (RR: 0.88, 95% CI: 0.72-1.08, p = 0.21). Subgroup analyses stratified by albuminuria status revealed no significant benefits of RAS inhibitors, regardless of albuminuria presence. The findings emphasize the need for cautious interpretation due to limited sample sizes, wide confidence intervals, and low precision. These results highlight the importance of considering not only RAS inhibitors but also other antihypertensive drugs as the first-line choice for blood pressure control in diabetic patients, with careful attention to side effects and other relevant factors.

A multicentral prospective cohort trial of a pharmacist-led nutritional intervention on serum potassium levels in outpatients with chronic kidney disease: The MieYaku-Chronic Kidney Disease project

Although dietary potassium restriction is an acceptable approach to hyperkalemia prevention, it may be insufficient for outpatients with chronic kidney disease (CKD). Most outpatients with CKD use community pharmacies owing to the free access scheme in Japan. The MieYaku-CKD project included a community pharmacist-led nutritional intervention for dietary potassium restriction, with the goal of determining its efficacy for patients' awareness of potassium restriction and serum potassium levels in outpatients with CKD. This was a five-community pharmacy multicenter prospective cohort study with an open-label, before-and-after comparison design. Eligible patients (n = 25) with an estimated glomerular filtration rate (eGFR) < 45 mL/min/1.73 m2 received nutritional guidance from community pharmacists. The primary outcome was a change in serum potassium levels at 12 weeks post-intervention. The eligible patients' knowledge, awareness, and implementation of potassium restriction were evaluated using a questionnaire. The median value of serum potassium was significantly reduced from 4.7 mEq/L before to 4.4 mEq/L after the intervention [p < 0.001, 95% confidence interval (CI): 0.156-0.500], with no changes in eGFR (p = 0.563, 95% CI: -2.427-2.555) and blood urine nitrogen/serum creatinine ratio (p = 0.904, 95% CI: -1.793-1.214). The value of serum potassium had a tendency of attenuation from 5.3 to 4.6 mEq/L (p = 0.046, 95% CI: 0.272-1.114) in the eGFR < 30 mL/min/1.73 m2 group. A questionnaire revealed that after the intervention, knowledge and attitudes regarding dietary potassium restriction were much greater than before, suggesting that the decrease in serum potassium levels may be related to this nutritional guidance. Our findings indicate that implementing a dietary potassium restriction guidance program in community pharmacies is feasible and may result in lower serum potassium levels in outpatients with CKD.

The prevalence of predialysis hyperkalemia and associated characteristics among hemodialysis patients: The RE-UTILIZE study

Introduction

Hyperkalemia (HK), defined as serum potassium (K⁺) >5.0 mEq/L, is an independent predictor of mortality in patients on maintenance hemodialysis (HD). This study investigated the annual prevalence of HK and examined patient characteristics potentially associated with a higher annual HK prevalence.

Methods

This retrospective observational cohort study used Dialysis Outcomes and Practice Patterns Study (DOPPS) survey data from US patients undergoing in‐center HD thrice weekly from 2018 to 2019. The primary endpoint was the proportion of patients with any predialysis HK (K⁺ >5.0 mEq/L) within 1 year from the index date (date of DOPPS enrollment), using the first hyperkalemic K⁺ value. Secondary endpoints were the proportion of patients with moderate‐to‐severe (K⁺ >5.5 mEq/L) or severe (K⁺ >6.0 mEq/L) HK.

Findings

Overall, 9347 patients on HD were included in this analysis (58% male and 49% aged >66 years). Any predialysis HK (K⁺ >5.0 mEq/L) occurred in 74% of patients within 1 year of the index date, 52% within 3 months, and 38% within 1 month. The annual prevalence of moderate‐to‐severe and severe HK was 43% and 17%, respectively. Recurrent HK (at least two K⁺ >5.0 mEq/L within 1 year) occurred in 60% of patients, and 2.8% of patients were prescribed an oral K⁺ binder. Multivariable logistic regression analysis showed younger age, female sex, Hispanic ethnicity, and renin–angiotensin–aldosterone system inhibitor use were significantly associated with a higher annual prevalence of any predialysis HK, while Black race, obesity, recent initiation of HD, and dialysate K⁺ bath concentration ≥3 mEq/L were associated with a lower prevalence of HK.

Discussion

The annual prevalence of predialysis HK and recurrence were high among US patients on HD, whereas oral K⁺ binder use was low. Further studies are needed to understand the impact of dialysate K⁺ bath concentrations on predialysis HK among patients on HD.

A phase 3 multicenter open-label maintenance study to investigate the long-term safety of sodium zirconium cyclosilicate in Japanese subjects with hyperkalemia

BACKGROUND

Hyperkalemia is associated with many chronic diseases and renin-angiotensin-aldosterone system inhibitor therapy. Sodium zirconium cyclosilicate (SZC), an oral, highly selective cation-exchanger, is approved for the treatment of hyperkalemia.

METHODS

This phase 3, multicenter, open-label, single-arm, flexible-dose study assessed the safety and efficacy of SZC in Japanese patients with hyperkalemia during a correction phase of up to 3 days and long-term (1 year) maintenance phase (NCT03172702).

RESULTS

Overall, 150 patients received treatment during both study phases; the study population was generally representative of hyperkalemic Japanese patients in clinical practice. Most patients (78.7%) had three doses of SZC during the correction phase. All but one patient received SZC for ≤ 48 h before transitioning to the maintenance phase. In the maintenance phase, mean (standard deviation; SD) exposure to the study drug was 319.4 (98.1) days and mean (SD) dose was 7.38 (2.85) g/day. Adverse events (AEs) were reported in 131 patients (87.3%); most were mild. The most common treatment-related AEs as evaluated by investigators were constipation (6.7%), peripheral edema (4.0%), and hypertension (2.7%). In the correction phase, 78.7% of patients were normokalemic at 24 h and 98.7% within 48 h; ≥ 65.5% maintained normokalemia throughout the maintenance phase.

CONCLUSION

After a year of exposure, SZC treatment was well tolerated by Japanese patients and potassium levels were well controlled.

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.

Prevalence and factors associated with false hyperkalaemia in Asians in primary care: a cross-sectional study (the Unlysed Hyperkalaemia- the Unseen Burden (UHUB) study)

Serum potassium is part of routine laboratory tests done for patients with hypertension or diabetes mellitus in primary care. Those found to have raised potassium (K>5.5 mmol/L) are recalled for repeat potassium in emergency departments or primary care clinics. Repeat potassium are often normal (≤5.5 mmo/L), that is, false hyperkalaemia. Haemolysis is known to cause false hyperkalaemia. We postulated that unlysed false hyperkalamia was prevalent and was associated with factors such as delayed processing time.

OBJECTIVE

We aimed to determine the prevalence of unlysed false hyperkalaemia and the factors associated with false-and-true-hyperkalaemia.

SETTING

Outpatients in a cluster of public primary care clinics (polyclinics) in Singapore.

PARTICIPANTS

All patients of any ethnicity aged ≥21 with serum potassium test done.

METHODS

Electronic health records of index patients with potassium >5.5 mmol/L and its corresponding laboratory processing time in seven local polyclinics were reviewed between August 2015 and August 2017. Haemolysed specimens and patients on sodium polystyrene sulfonate (SPS) suspension were excluded. If repeat potassium level was ≤5.5 mmol/L within 8 days, the case was defined as false hyperkalaemia. The proportion of such patients was computed to determine its prevalence. Linear and logistic regressions were used to identify the associated factors.

RESULTS

The study population comprised of 3014 index cases, of which 1575 had repeat potassium tests without preceding SPS. 86.4% (1362/1575) of them had potassium ≤5.5 mmol/L. The average processing time among specimens with potassium ≥6.0 mmol/L was 50 min longer, compared with those with potassium <5.1 mmol/L. Risk factors significantly associated with false hyperkalaemia included estimated glomerular filtration rate (eGFR) (60-89 mL/min/1.73 m², OR=3.25, p<0.001;>90 mL/min/1.73 m², OR=3.77, p<0.001) and delayed laboratory processing time (beta coefficient 0.001, p<0.001).

CONCLUSION

The prevalence of false hyperkalaemia was 86.4%. Recommendation to repeat potassium tests may target those with eGFR<60ml/min/1.73m².

Hyperkalemia: A persisting risk. A case report and update on current management

We report a case of hemodynamic instability due to bradycardia on the basis of severe hyperkalemia. Diabetic ketoacidosis and acute kidney injury together with polypharmacy triggered the acute onset. Potentially life-threatening hyperkalemia is often induced by drug interactions. ECG features may be crucial for diagnosis, and treatment depends on setting and resources.

Correction of serum potassium with sodium zirconium cyclosilicate in Japanese patients with hyperkalemia: a randomized, dose-response, phase 2/3 study

BACKGROUND

Sodium zirconium cyclosilicate (SZC) is an oral potassium binder approved to treat hyperkalemia in adults in a number of countries, including Japan.

METHODS

This phase 2/3, randomized, double-blind, placebo-controlled, dose-response study (ClinicalTrials.gov: NCT03127644) was designed to determine the efficacy and safety of SZC in Japanese adults with hyperkalemia. Patients with serum potassium (sK⁺) concentrations ≥ 5.1- ≤ 6.5 mmol/L were randomized 1:1:1 to SZC 5 g, SZC 10 g, or placebo three times daily for 48 h (six doses total). The primary efficacy endpoint was the exponential rate of change in sK⁺ over 48 h. The proportion of patients with normokalemia (sK⁺ 3.5-5.0 mmol/L) at 48 h and adverse events (AEs) were also evaluated.

RESULTS

Overall, 103 patients (mean age, 73.2 years; range 50-89 years) received SZC 5 g (n = 34), SZC 10 g (n = 36), or placebo (n = 33). The exponential rate of sK⁺ change from 0 to 48 h versus placebo was - 0.00261 (SZC 5 g) and - 0.00496 (SZC 10 g; both P < 0.0001). At 48 h, the proportions of patients with normokalemia were 85.3%, 91.7%, and 15.2% with SZC 5 g, SZC 10 g, and placebo, respectively. No serious AEs were reported. Hypokalemia (sK⁺  < 3.5 mmol/L) occurred in two patients in the SZC 10 g group; normokalemia was re-established within 6 days and no treatment-related AEs were reported.

CONCLUSION

SZC is effective and well tolerated in Japanese patients with hyperkalemia.

The burden of hyperkalemia in Germany - a real world evidence study assessing the treatment and costs of hyperkalemia

Background

Hyperkalemia (HK) can affect health outcomes and quality of life, as it is referred to as a potentially life-threatening condition caused by an increased serum potassium concentration in the blood. Patients suffering from heart failure or chronic kidney diseases are at a higher risk of HK, which can further be amplified by the treatment received. To date, data on HK prevalence is lacking for Germany and the aims of this study were to assess HK and compare health-relevant outcomes and healthcare costs between HK patients and non-HK patients.

Methods

The InGef research database containing healthcare claims of over 4 million individuals in Germany was utilized for this retrospective, matched cohort analysis. Patients with non-acute outpatient treated and a subgroup of patients with chronic HK, were identified in 2015 with an individual 1 year pre- and post-index period, taking the first observable HK diagnosis/treatment in 2015 into account as the index event. To identify non-acute outpatient treated HK patients, at least two ICD-10-GM diagnosis codes E87.5 “Hyperkalemia” and/or prescriptions of polystyrene sulfonate were required. Chronic HK patients had additional diagnoses and/or prescriptions in all quarters following the first observable HK diagnosis. Patients without HK were matched 1:1 to the respective HK cohorts.

Results

In the year 2015, 3333 patients with non-acute outpatient treated HK were identified of which 1693 were patients with chronic HK. After matching, 3191 and 1664 HK patients and controls were available for analysis. A significantly higher number of hospitalizations was observed for both HK cohorts in comparison to their matched controls. Dialysis initiation as well as the healthcare costs were higher for both HK cohorts when compared to their matched counterparts.

Conclusions

The disease burden was higher for patients with HK, based on a higher proportion of patients with dialysis initiation and higher healthcare costs.

A Study of Morphological Changes in Renal Afferent Arterioles Induced by Angiotensin II Type 1 Receptor Blockers in Hypertensive Patients

BACKGROUND

Renin-angiotensin-aldosterone system blockers are known to reduce hypertrophy of vascular smooth muscle cells (SMCs) in hypertensive cases. However, we have reported marked proliferative changes of renal afferent arteriolar SMCs in rats induced by a long-term administration of angiotensin II type 1 receptor blockers (ARBs) and an angiotensin-converting enzyme inhibitor (ACEI). In this study, we examined the morphological changes of afferent arteriolar walls in human kidneys with or without ARBs/ACEIs.

METHODS

Forty-four wedge resections were taken from patients aged 45-74 years from 92 nephrectomized kidneys due to malignancy at Toho University Omori Medical Center between 2013 and 2016. They were divided into the following three groups: 18 hypertensive patients treated with antihypertensive agents including ARBs or ACEIs (the HTARB group), 6 hypertensive patients treated with calcium channel blockers without ARBs/ACEIs (the HTCCB group), and 20 normotensive patients (the normotensive group) as a control. Cases expecting vascular changes such as diabetes were excluded. In each case renal arterioles were measured as the ratio of inner/outer arteriolar diameter, and pathologists estimated morphological abnormal changes, scoring each specimen independently.

RESULTS

The ratio in the HTARB group was 0.39 ± 0.05 (mean ± SD), and was significantly the lowest among the three groups (0.46 ± 0.02 in the HTCCB, 0.53 ± 0.02 in the normotensive group; p = 0.0107 vs. HTCCB, p = 0.00001 vs. normotensive). The ratio in the three groups significantly correlated with the estimated glomerular filtration rate (r = 0.4915, p < 0.0007). The afferent arteriolar SMCs in the HTARB group frequently showed marked proliferative and irregular changes. The score of SMC abnormalities estimated regarding the proliferation, irregularity of the arrangement, and size in hilar afferent arteriolar SMCs was highest in the HTARB group and showed statistical significance (p = 0.0088, p = 0.00001, and p = 0.025 versus other two groups).

CONCLUSIONS

We consider that these morphological changes in arterioles are induced by ARBs/ACEIs. These changes could induce an important suppression of glomerular hyperfiltration and could lead to glomerular ischemia. However, the clinical consequences of these morphological changes in correlation with ARBs/ACEIs were not sufficiently clear and require further analysis. We should consider renal arteriolar morphological changes when using ARBs/ACEIs.

Drug-induced endocrine blood pressure elevation

Patients with uncontrolled hypertension are at risk for cardiovascular complications. The majority of them suffers from unidentified forms of hypertension and a fraction has so-called secondary hypertension with an identifiable cause. The patient's medications, its use of certain herbal supplements and over-the-counter agents represent potential causal factors for secondary hypertension that are often overlooked. The current review focuses on drugs that are likely to elevate blood pressure by affecting the human endocrine system at the level of steroid synthesis or metabolism, mineralocorticoid receptor activity, or by affecting the catecholaminergic system. Drugs with known adverse effects but where benefits outweigh their risks, drug candidates and market withdrawals are reviewed. Finally, potential therapeutic strategies are discussed.