Hyperkalemia: pathophysiology, risk factors and consequences

The role of sodium zirconium cyclosilicate drug utilization in managing hyperkalemia: impact on healthcare resource utilization and on maintenance of renin-angiotensin-aldosterone system inhibitor therapy in Italian clinical practice

AIMS

Hyperkalemia (HK) is prevalent in patients with chronic kidney disease (CKD) and heart failure, particularly those on renin-angiotensin-aldosterone system inhibitors (RAASi). However, HK treatment often necessitates RAASi discontinuation. Sodium zirconium cyclosilicate (SZC), reimbursed in Italy since 2021, offers a new treatment option for HK. This study aimed to assess real-world SZC use and resulting economic rebounds in Italy.

METHODS

Using administrative databases of healthcare entities covering about 6 million residents, patients with at least one prescription of SZC from Jan-2022 to Jun-2023 were identified. Patients receiving other potassium binders after SZC initiation were excluded. A logistic regression model estimated odds ratios (OR) with 95% confidence interval (95%CI) for predictors of long-term SZC use (>90 days), including age, sex, CKD status, and comorbidities. Univariate regression identified the potential association between each individual predictor and the likelihood of long-term treatment, followed by multivariate analysis adjusted for confounders. A backward stepwise logistic regression method retained only significant predictors, enhancing model accuracy.

RESULTS

The study identified 355 SZC-treated patients (mean age 70.4 years, 64.2% male). CKD was found in 69.3% (47.6% on dialysis), with common comorbidities including hypertension (57.5%), diabetes (43.4%), and heart failure (23.4%). RAASi use was observed in 68.7% before SZC initiation, and RAASi discontinuation was lower in long-term SZC users compared to short-term SZC users (41.2 vs. 56.6%, p = 0.048). Short-term SZC treatment (≤90 days) was more frequent (83.1%) and predicted by dialysis (OR = 0.22). Healthcare costs over 6 months averaged €7,943 for short-term users (dialysis: €3,452) and €6,647 for long-term users (dialysis: €1,130).

CONCLUSIONS

This real-world study showed that nearly 17% of patients continued SZC therapy for ≥90 days. Long-term therapy was associated with lower RAASi discontinuation and reduced healthcare costs due to hospitalizations and outpatient specialist services, suggesting that SZC can potentially provide clinical and economic benefits for HK management.

Hyperkalemia Is an Underestimated Risk Factor in COPD

Background

Hyperkalemia increases mortality in various patient populations. The risk of hyperkalemia in COPD patients is poorly recognized. Hyperkalemia may increase cardiovascular mortality during and soon after COPD exacerbations.

Patients and Methods

A cohort based on two clinical trials comprising 7968 patients with moderate-to-very severe COPD was analysed retrospectively for associations between hyperkalemia and common comorbidities such as chronic kidney disease, diabetes mellitus (DM), or renin-angiotensin-aldosterone system inhibitor use.

Results

Overall, 6.4% of 7968 patients had hyperkalemia (5.3% Global Initiative for Chronic Obstructive Lung Disease (GOLD) stage 2, 6.8% GOLD 3, and 8.0% GOLD 4). COPD severity was associated with significantly higher hyperkalemia risk in GOLD 3 (odds ratio [OR]=1.28, 95% CI 1.04-1.58) and GOLD 4 (OR=1.64, 95% CI 1.19-2.22) versus GOLD 2 patients. Hyperkalemia cases increased with decreasing renal function. Patients with moderate-to-severe renal impairment had >2-fold increased hyperkalemia risk versus those with normal renal function (OR=2.29, 95% CI 1.71-3.04). DM was associated with increased hyperkalemia risk (OR=1.28, 95% CI 1.02-1.59). Angiotensin-converting-enzyme inhibitor (ACEi) use increased hyperkalemia risk (OR=1.25, 95% CI 1.02-1.53). Unexpectedly, the association between hyperkalemia and renin-angiotensin-aldosterone system inhibitor use was statistically significant only in the normal renal function group (OR=1.63, 95% CI 1.13-2.34).

Conclusion

Hyperkalemia risk is higher in severe and very severe COPD patients than patients with moderate COPD. Hyperkalemia was also associated with decreasing kidney function, DM, and ACEi use. Serum potassium levels should be monitored regularly in patients with COPD, particularly those with GOLD-3 and 4.

Association of Hypokalemia With Mortality in Patients Undergoing Hemodialysis: A Systematic Review and Meta-Analysis

BACKGROUND

Potassium imbalance, particularly hypokalemia, is a critical risk factor for adverse outcomes in patients undergoing hemodialysis (HD). However, the association between hypokalemia and mortality is unclear.

METHODS

For this systematic review and meta-analysis, we assessed the association between hypokalemia and mortality in patients undergoing HD. We performed a systematic search of electronic databases (PubMed, Embase, Cochrane Library, and Scopus) to identify relevant studies published up to April 2024. Eligible studies were prospective or retrospective cohort studies reporting hazard ratios (HRs) for mortality in association with the presence of hypokalemia among patients undergoing HD. We used the assessed study Newcastle-Ottawa Scale to assess quality of the selected studies.

RESULTS

We carried out both qualitative and quantitative assessments. For the meta-analysis, we pooled the HRs for all-cause and cardiovascular mortalities. The overall pooled HR for all-cause mortality and cardiovascular mortality were 1.34 (95% CI, 1.15, 1.55) and 1.49 (95% CI, 1.12, 1.98), respectively, indicating significant associations between hypokalemia and all-cause mortality and cardiovascular mortality in patients undergoing HD. Additionally, we conducted subgroup analyses based on study design, geographical location, type of dialysis, and serum potassium levels.

CONCLUSION

Our findings provide robust evidence of a significant association between hypokalemia and mortality in patients undergoing HD. Early detection and proactive management of hypokalemia are crucial for improving outcomes and reducing mortality risk in these patients.

Hyperkalemia management: a multidisciplinary expert panel's perspective on the role of new potassium binders

Hyperkalemia is a potentially life-threatening condition frequently encountered in clinical practice, particularly among patients with chronic kidney disease, heart failure, diabetes, and hypertension and those undergoing treatment with renin-angiotensin-aldosterone system inhibitors (RAASi). The management of chronic and acute hyperkalemia is complex and requires timely intervention to prevent severe complications such as cardiac arrhythmias and sudden death. Traditional therapeutic approaches to chronic hyperkalemia, including dietary potassium restriction, use of diuretics, and administration of cation-exchange resins like sodium polystyrene sulfonate, often suffer from limitations like gastrointestinal side effects, variable efficacy, delayed onset of action, and RAASi treatment discontinuation. In recent years, the development of new potassium binders, specifically patiromer and sodium zirconium cyclosilicate (SZC), has revolutionized the management of hyperkalemia. Patiromer, a non-absorbed polymer, binds potassium in the gastrointestinal tract in exchange for calcium, thus facilitating its excretion. SZC operates by exchanging sodium and hydrogen ions for potassium, leading to efficient potassium removal. Both agents have demonstrated rapid and sustained reductions in serum potassium levels, coupled with favorable safety and tolerability profiles, in multiple clinical trials. This review article, authored by a multidisciplinary group of Portuguese experts in hyperkalemia management, provides an in-depth analysis of the efficacy and safety of current therapeutic strategies and highlights the clinical potential of new potassium binders. The introduction of patiromer and SZC offers significant advantages over traditional therapies, providing effective and better-tolerated options for patients. The review highlights the role of these novel agents in contemporary hyperkalemia management and calls for ongoing research to further refine treatment protocols and improve patient outcomes.

Hyperuricemia prevalence and its risk factors in uremic patients undergoing maintenance hemodialysis

BACKGROUND

To explore the prevalence of hyperuricemia and its associated factors in uremic patients undergoing maintenance hemodialysis (MHD).

METHODS

Two hundred two uremic patients undergoing MHD for ≥ 3 months, in Jinshan Hospital, Fudan University, were enrolled. Pre-dialysis blood samples were tested during March 1st, 2023 to April 30th, 2023. Demographic characteristics were recorded. The prevalence of hyperuricemia, defined as serum uric acid (SUA) ≥ 420 μmol/L, was investigated. Individuals were divided into hyperuricemia (HUA) and non-hyperuricemia (n-HUA) groups. The demographic characteristics, residual kidney function, nutritional status, acid-base metabolism, electrolyte and lipid metabolism were compared between groups. The associated factors for hyperuricemia in MHD patients were identified by logistic regression.

RESULTS

The median SUA level of the enrolled patients was 458.50 (392.25, 510.75) μmol/L. 134 (66.34%) candidates met the diagnostic criteria of hyperuricemia. The median SUA level in HUA group was 491.00 (459.50, 543.50) μmol/L. Compared to those in n-HUA group, subjects in HUA group showed lower estimated glomerular filtration rate and blood CO2 level, but higher levels of body mass index, geriatric nutritional risk index, plasma phosphate, potassium, pre-albumin, albumin, serum creatinine (Scr) and urea nitrogen. Logistic regression indicated that Scr (OR 1.002, 95% CI 1.001-1.004, P = 0.003), albumin (OR 1.165, 95%CI 1.011-1.342, P = 0.035), and blood potassium (OR 1.673, 95% CI 1.009-2.773, P = 0.046) were associated factors for hyperuricemia in uremic patients undergoing MHD.

CONCLUSION

Hyperuricemia was highly prevalent among uremic MHD patients. Elevated levels of Scr, albumin and plasma potassium were independent associated factors for hyperuricemia.

Hyperkalemia and the Risks of Adverse Cardiovascular Outcomes in Patients With Chronic Kidney Disease

BACKGROUND

This real-world evidence study compared risks of cardiovascular events in hospital settings among patients with chronic kidney disease (CKD) with and without hyperkalemia.

METHODS AND RESULTS

Adults with CKD stages 3b/4 with and without hyperkalemia were identified from Optum's deidentified Market Clarity Data (January 2016-August 2022). Patients with hyperkalemia were exact and propensity score matched to patients without hyperkalemia. The index date was the first CKD stage 3b/4 diagnosis with ≥1 hyperkalemia diagnosis and ≥1 serum potassium >5.0 mmol/L in the preceding 12 months (baseline) for patients with hyperkalemia and a randomly selected CKD stage 3b/4 diagnosis for controls. Cardiovascular composite end points included major adverse cardiovascular events plus (a composite end point of all-cause mortality, myocardial infarction, stroke, or heart failure) and cardiac arrhythmias (a composite end point of new onset atrial fibrillation and other atrial and ventricular arrythmias), all in the hospital setting. We compared cardiovascular events between cohorts using cause-specific Cox proportional hazards regression. The study included 5301 matched pairs in the analysis of major adverse cardiovascular events plus and 5564 in the analysis of arrhythmia. Cardiovascular events were more likely among patients with hyperkalemia relative to those without hyperkalemia, with the risk of major adverse cardiovascular events plus increased by 32% (23%-40%) and the risk of arrhythmia increased by 59% (44%-75%; both P<0.001).

CONCLUSIONS

Among patients with CKD stages 3b/4, patients with hyperkalemia experienced significantly higher risks of major adverse cardiovascular events and arrhythmia in hospital settings relative to patients without hyperkalemia.

Polypharmacy and anticholinergic burden as risk factors for postoperative delirium in surgical medicine

PURPOSE

Polypharmacy is a widespread phenomenon in older patients. In particular, the anticholinergic burden of medication is an important risk factor for delirium due to age-related changes in the cholinergic system.

METHODS

Preoperative medication, including the calculation of the anticholinergic burden (ACB), was recorded in a prospective study (421 patients) to identify potential risks associated with medication intake. Postoperative delirium screening was carried out daily.

RESULTS

The study included 199 women (47.3%) and 222 men (52.7%) aged 80.8 ± 6.7 years and 78.8 ± 6.2 years, respectively. Antidepressants odds ratio (OR) 3.16 (95% confidence interval. CI, 1.51-6.64), antidiabetic drugs OR 2.53 (95% CI 1.27-5.03), neuroleptics OR 3.52 (95% CI 1.70-7.28) and Parkinson medication OR 5.88 (95% CI 1.95-17.7) showed a significantly higher risk for delirium. The ACB score revealed an anticholinergic burden in 43 patients (10.4%). The delirium rate was 25.6% (n = 11) and 11.0% (n = 40) had no anticholinergic burden. A significant correlation can be demonstrated with χ2(1) = 7.52, p = 0.006, Cramer's V = 0.136. There was a 2.79-fold higher risk of delirium (OR 2.79, 95% CI 1.31-5.97).

CONCLUSION

The standardized recording of medication is essential, especially when identifying patients at risk of suffering from delirium. The use of the ACB score to assess the anticholinergic burden is a simple and reliable screening tool and should be part of a preoperative geriatric assessment.

The role of cation-exchange resins in hyperkalemia management

Hyperkalemia, characterized by elevated serum potassium levels, poses significant health risks, including life-threatening cardiac arrhythmias. The management of hyperkalemia has evolved, incorporating calcium polystyrene sulfonate (CPS) and newer agents such as sodium zirconium cyclosilicate (SZC) and patiromer alongside traditional treatments. This review provides a comprehensive examination of current management strategies for hyperkalemia, focusing on the comparative effectiveness, safety profiles, and patient preferences concerning CPS, SZC, and patiromer. Through an analysis of clinical trials, safety data, and guidelines, we highlight SZC's rapid action and favorable safety profile compared to CPS, which has been a standard treatment option for years. Additionally, the review explores patiromer, other emerging treatments, and future directions in hyperkalemia management, including the potential benefits of combination therapies and the role of personalized medicine. The findings suggest a shift toward newer potassium-binding agents in clinical practice, underscored by the need for individualized treatment approaches based on patient-specific factors. This article aims to guide clinicians in optimizing hyperkalemia management, ensuring effective, safe, and patient-centered care.

Optimizing epilepsy treatment: the impact of circadian rhythms and medication timing on conversion rates and survival

BACKGROUND

The progression from isolated seizures to status epilepticus (SE) is a critical clinical issue. This study explores the influence of circadian rhythms on this transition and assesses the impact of medication timing on SE conversion rates and patient survival.

AIM

To determine the circadian patterns in the transition from isolated seizures to SE and to evaluate the efficacy of medication timing in reducing this conversion and improving survival outcomes.

DESIGN AND METHODS

Utilizing the eICU Collaborative Research Database v2.0, a retrospective analysis was performed on patients at risk of SE conversion. The study analyzed the correlation between SE conversion timing and AEDs administration in relation to circadian rhythms, using a Logit model to evaluate the impact of medication timing on SE conversion and survival.

RESULTS

The transition from isolated seizures to SE showed distinct circadian patterns, with a delayed acrophase. Early night-time AEDs administration significantly reduced conversion rates. Medication timing also influenced survival rates, with higher survival during specific periods.

CONCLUSION

Circadian rhythms significantly affect the transition from isolated seizures to SE. Timely AEDs administration is crucial for reducing conversions and improving survival. A chronotherapeutic approach aligning AEDs administration with individual circadian vulnerabilities could advance epilepsy management in ICU settings. Future research should focus on personalized medication strategies that utilize circadian rhythms to optimize treatment effects.

A Comparative Study Assessing the Incidence and Degree of Hyperkalemia in Patients on Unfractionated Heparin versus Low-Molecular Weight Heparin

Background

Heparin and its derivates, including unfractionated heparin (UFH) and low molecular weight heparin (LMWH), are among the most commonly used anticoagulants. Nonetheless, their use has been associated with hyperkalemia.

Objective

To determine and compare the incidence, magnitude, and potential risk factors of hyperkalemia in patients receiving UFH versus LMWH in a real-world clinical setting.

Methods

A retrospective observational study was conducted involving all adult hospitalized patients who received UFH, dalteparin or enoxaparin. Electronic medical records were reviewed over a 12-month period, collecting data on demographic, laboratory, comorbidity, and medication-related variables. Data were analyzed using multivariate logistic regression.

Results

A total of 929 patients met the eligibility criteria, with a mean age of over 40 years across all groups. Of these, 56.3%, 17.2%, and 15.7% experienced hyperkalemia with UFH, dalteparin and enoxaparin, respectively. The incidence of hyperkalemia was significantly higher with UFH compared to enoxaparin and dalteparin (p<0.001). Diabetes mellitus was associated with a higher incidence of hyperkalemia (OR 1.79, 95% CI 1.241-2.581, p=0.002), as was the concomitant use of co-trimoxazole (OR 2.244, 95% CI 1.137-4.426, p=0.02). Whilst chronic kidney disease and the use of two or more hyperkalemia-inducing agents were not statistically significant, they were retained in the model as they were associated with more than a 10% increase in the odds of hyperkalemia.

Conclusion

Heparin (UFH, LMWH) administration was associated with a risk of hyperkalemia particularly in patients with diabetes mellitus and those concurrently receiving co-trimoxazole.

Hyperkalemia burden and treatment patterns in Chinese patients on hemodialysis: final analysis of a prospective multicenter cohort study (PRECEDE-K)

OBJECTIVES

Patients with end-stage renal disease (ESRD) on hemodialysis (HD) are at risk for hyperkalemia (HK), associated with cardiac arrhythmia and sudden death. Data on the burden of HK and management techniques among HD patients in China are still scarce. This study assessed the treatment modalities, recurrence, and prevalence of HK in Chinese HD patients.

METHODS

In this prospective cohort study conducted from May 2021 to July 2022, patients aged ≥18 years who had ESRD and were on HD were enrolled from 15 centers in China (up to 6 months).

RESULTS

Overall, 600 patients were enrolled. At the baseline visit, mean (± standard deviation) urea reduction ratio was 68.0% ± 9.70 and Kt/V was 1.45 ± 0.496. Over 6 months, 453 (75.5%) patients experienced HK, of whom 356 (78.6%) recurred. Within 1, 2, 3, 4, 5, and 6 months, 203 (44.8%), 262 (57.8%), 300 (66.2%), 326 (72.0%), 347 (76.6%), and 356 (78.6%) patients had at least one HK recurrence event, respectively. The proportions of patients with ≥1, 2, 3, 4, 5, or 6 HK recurrence events were 356 (78.6%), 306 (67.5%), 250 (55.2%), 208 (45.9%), 161 (35.5%), and 110 (24.3%), respectively. Among the 453 patients who experienced HK, only 24 (5.3%) were treated with potassium binders: seven (1.5%) with sodium polystyrene sulfonate, 13 (2.9%) with calcium polystyrene sulfonate, and six (1.3%) with sodium zirconium cyclosilicate.

CONCLUSION

Since HK is a chronic illness, long-term care is necessary. Patients on HD should have effective potassium management on non-dialysis days, yet our real-world population rarely used potassium binders.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier NCT04799067.

Management Strategies for Potassium Levels During Non-steroidal Mineralocorticoid Receptor Antagonist Therapy: A Comprehensive Review

Diabetic kidney disease (DKD) is a leading cause of chronic kidney disease (CKD). Recent advancements highlight the role of finerenone, a non-steroidal mineralocorticoid receptor antagonist (nsMRA), in DKD management. Studies like FIDELIO-DKD, FIGARO-DKD, and FIDELITY have demonstrated finerenone's efficacy in reducing CKD progression and cardiovascular risks in DKD patients. Trials reveal higher incidence of hyperkalemia in finerenone groups compared to controls. Asian populations are noted to have a higher risk, emphasizing the need for close monitoring. To manage hyperkalemia, evidence-based protocols suggested starting finerenone with potassium level below 4.8mEq/L, discontinuing if potassium level exceed 5.5mEq/L. Strategies include dietary potassium restriction, potassium binders, and frequent monitoring. While these managements help mitigate risks, real-word challenges call for further evidence to refine practical guidelines. Finerenone emerges as a promising therapy for DKD but requires careful management to prevent hyperkalemia, ensuring optimal patient outcomes.

Hyperkalemia and Risk of CKD Progression: A Propensity Score-Matched Analysis

Key Points

Hyperkalemia is a known complication of CKD; however, it is not known whether hyperkalemia directly contributes to CKD progression and risk of death. We found that patients with stages 3b/4 CKD and hyperkalemia had higher risk of CKD progression and death than matched patients without hyperkalemia.

Background

Hyperkalemia is a known complication of CKD; however, it is not known whether hyperkalemia directly contributes to CKD progression and the risk of death. Clarifying the extent to which hyperkalemia is associated with CKD progression and mortality can inform clinical practice and guide future research. The objective of this study was to quantify the risks of CKD progression and mortality associated with hyperkalemia in patients with stages 3b/4 CKD.

Methods

This was a real-world, exact and propensity score matched, observational cohort study using data (January 2016 to December 2021) from Optum's deidentified Market Clarity Data, a large US integrated insurance claims/electronic medical record database. The study included matched adult patients with stages 3b/4 CKD with and without hyperkalemia, not regularly treated with an intestinal potassium (K+) binder. Measured outcomes were CKD progression and all-cause mortality. CKD progression was defined as diagnosis of CKD stage 4 (if stage 3b at index), CKD stage 5 or kidney failure, or receipt of dialysis or kidney transplantation.

Results

After matching, there were 6619 patients in each of the hyperkalemia and nonhyperkalemia cohorts, with a mean follow-up time of 2.12 (SD, 1.42) years. Use of any renin-angiotensin-aldosterone system inhibitors during baseline was common (75.9%), and most patients had CKD stage 3b (71.2%). Patients with hyperkalemia had a 1.60-fold (95% confidence interval, 1.50 to 1.71) higher risk of CKD progression and a 1.09-fold (1.02 to 1.16) higher risk of all-cause mortality relative to patients without hyperkalemia. Relative risks of CKD progression associated with hyperkalemia were similar within the subset of patients receiving renin-angiotensin-aldosterone system inhibitor, across CKD stages, and when alternative definitions of CKD progression were used.

Conclusions

Patients with CKD stages 3b/4 and hyperkalemia experienced significantly higher risks of CKD progression and all-cause mortality than propensity score matched patients without hyperkalemia.

Evaluation of Dactylopius opuntiae Extract for Xanthine Oxidase Inhibition and Serum Uric Acid Reduction in a Hyperuricemic Mouse Model

Background/Objectives: Current urate-lowering therapies may cause serious side effects in patients. Thus, alternative treatments are needed to regulate uric acid (UA) levels in patients with hyperuricemia associated with kidney injury, and natural antioxidant sources have demonstrated utility in this field. For the first time, our study evaluated the effects of an extract of Dactylopius opuntiae insects on the levels of xanthine oxidase (XO) enzymes and synthetic free radicals in vitro and in vivo. Methods: Insects were bred and collected, and two different extracts (D1 and D2) were obtained. For both extracts, XO inhibition and radical scavenging assays were performed. Subsequently, serum purine levels and renal markers were quantified in male BALB/c mice who received a hyperuricemia induction using potassium oxonate, hypoxanthine, and gentamicin. Results: The D2 extract contained 18,037.7 µg/mL of carminic acid, inhibited 53.2% of XO activity at one concentration, and showed IC50 values of 18,207.8 and 5729.6 µg/mL against ABTS and DPPH radicals, respectively. D2 administration reduced serum UA and creatinine levels and prevented an increase in kidney weight and reduction in renal antioxidant capacity caused by hyperuricemia induction and allopurinol use in mice. Despite the satisfactory antioxidant results obtained in vitro, the D1 extract killed the animal models due to its citric acid content. Conclusions: The D2 insect extract can be used as an effective urate-lowering therapy when the increased level of serum uric acid is due to kidney damage.

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.

Pathological and functional significance of aging mouse kidneys: clinical implications to reduce the risk of hyper- or hypokalemia in the elderly

Elderly patients are prone to develop hyper- or hypokalemia, since they are susceptible to drugs or diets that affect the urinary or fecal potassium (K+) excretion. In aging mouse kidneys, in addition to glomerulosclerosis, proximal tubular atrophy, and atherosclerosis in renal arterioles, there was diffuse tubulointerstitial fibrosis with a number of inflammatory leukocytes infiltrating into the cortical interstitium. Since these pathological features greatly influence renal K+ handling, slowing the progression of kidney aging would fundamentally reduce the risk of developing hyper- or hypokalemia. Immunohistochemistry demonstrated the overexpression of K+ channels (Kv1.3) in leukocytes within the cortical interstitium, which was strongly associated with "chronic inflammation" in aging kidneys and the subsequent progression of renal fibrosis. In our basic studies, antihypertensive drugs (benidipine, nifedipine, verapamil, diltiazem) and anticholesterol drugs (lovastatin, simvastatin, pravastatin) strongly suppressed the leukocyte Kv1.3 channels and thus exerted anti-inflammatory effects. Given such pharmacological properties of these drugs, they may also be useful in slowing the progression of tubulointerstitial fibrosis in aging kidneys and reducing the risk of hyper- or hypokalemia in elderly patients.

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.

GLP-1RA vs DPP-4i Use and Rates of Hyperkalemia and RAS Blockade Discontinuation in Type 2 Diabetes

Importance

Hyperkalemia is a common complication in people with type 2 diabetes (T2D) that may limit the use of guideline-recommended renin-angiotensin system inhibitors (RASis). Emerging evidence suggests that glucagon-like peptide-1 receptor agonists (GLP-1RAs) increase urinary potassium excretion, which may translate into reduced hyperkalemia risk.

Objective

To compare rates of hyperkalemia and RASi persistence among new users of GLP-1RAs vs dipeptidyl peptidase-4 inhibitors (DPP-4is).

Design, Setting, and Participants

This cohort study included all adults with T2D in the region of Stockholm, Sweden, who initiated GLP-1RA or DPP-4i treatment between January 1, 2008, and December 31, 2021. Analyses were conducted between October 1, 2023, and April 29, 2024.

Exposures

GLP-1RAs or DPP-4is.

Main Outcomes and Measures

The primary study outcome was time to any hyperkalemia (potassium level >5.0 mEq/L) and moderate to severe (potassium level >5.5 mEq/L) hyperkalemia. Time to discontinuation of RASi use among individuals using RASis at baseline was assessed. Inverse probability of treatment weights served to balance more than 70 identified confounders. Marginal structure models were used to estimate per-protocol hazard ratios (HRs).

Results

A total of 33 280 individuals (13 633 using GLP-1RAs and 19 647 using DPP-4is; mean [SD] age, 63.7 [12.6] years; 19 853 [59.7%] male) were included. The median (IQR) time receiving treatment was 3.9 (1.0-10.9) months. Compared with DPP-4i use, GLP-1RA use was associated with a lower rate of any hyperkalemia (HR, 0.61; 95% CI, 0.50-0.76) and moderate to severe (HR, 0.52; 95% CI, 0.28-0.84) hyperkalemia. Of 21 751 participants who were using RASis, 1381 discontinued this therapy. The use of GLP-1RAs vs DPP-4is was associated with a lower rate of RASi discontinuation (HR, 0.89; 95% CI, 0.82-0.97). Results were consistent in intention-to-treat analyses and across strata of age, sex, cardiovascular comorbidity, and baseline kidney function.

Conclusions

In this study of patients with T2D managed in routine clinical care, the use of GLP-1RAs was associated with lower rates of hyperkalemia and sustained RASi use compared with DPP-4i use. These findings suggest that GLP-1RA treatment may enable wider use of guideline-recommended medications and contribute to clinical outcomes in this population.

Tumour lysis syndrome

Tumour lysis syndrome (TLS) represents a critical oncological emergency characterized by extensive tumour cell breakdown, leading to the swift release of intracellular contents into the systemic circulation, outpacing homeostatic mechanisms. This process results in hyperuricaemia (a by-product of intracellular DNA release), hyperkalaemia, hyperphosphataemia, hypocalcaemia and the accumulation of xanthine. These electrolyte and metabolic imbalances pose a significant risk of acute kidney injury, cardiac arrhythmias, seizures, multiorgan failure and, rarely, death. While TLS can occur spontaneously, it usually arises shortly after the initiation of effective treatment, particularly in patients with a large cancer cell mass (defined as ≥500 g or ≥300 g/m2 of body surface area in children). To prevent TLS, close monitoring and hydration to improve renal perfusion and urine output and to minimize uric acid or calcium phosphate precipitation in renal tubules are essential. Intervention is based on the risk of a patient of having TLS and can include rasburicase and allopurinol. Xanthine, typically enzymatically converted to uric acid, can accumulate when xanthine oxidases, such as allopurinol, are administered during TLS management. Whether measurement of xanthine is clinically useful to optimize the use of allopurinol or rasburicase remains to be determined.

Heart Failure and Edema Costs in Patiromer and Sodium Zirconium Cyclosilicate Users

Key Points

Prior research suggests differences in rates of heart failure hospitalization or serious emergency department visits between patients on patiromer versus sodium zirconium cyclosilicate. Total costs of heart failure–related hospitalizations and emergency department visits may be lower in patients on patiromer compared with sodium zirconium cyclosilicate.

Background

Previous work suggested differences between patients taking patiromer or sodium zirconium cyclosilicate (SZC) in real-world risk of heart failure (HF) hospitalizations and edema hospitalizations or emergency department (ED) visits (edema events). We further investigated these differences to assess economic importance. Retrospective study using published event rates and mean costs derived from Optum's deidentified Clinformatics Data Mart Database.

Methods

We designed a model to estimate adjusted economic offsets that combined respective patiromer and SZC HF hospitalization (25.1 and 35.8; difference 10.7 [95% confidence interval (CI)2, 2.6 to 18.8]) and edema event (3.4 and 7.1; difference 3.6 [95% CI, 1.7 to 7.1]) rates/100 person-years from the original published work with costs from our parallel data extract spanning 2019–2021, adjusted to 2021 US dollars.

Results

In a base case of mean HF hospitalization, edema event, and 30-count potassium-binder prescription costs from our data extract, the estimated mean savings with patiromer was $1428 per person per year (95% CI, −$1508 to $4652). Respective costs per person per year for patiromer versus SZC were $8526 versus $12,622 (difference $4096 [95% CI, $116 to $7320]) for HF hospitalization and edema events, and $10,649 versus $7981 (difference −$2668) for potassium binders, totaling $19,175 for patiromer versus $20,603 for SZC.

Conclusions

With differing drug costs, hospitalization and ED costs offset this difference when event rates were numerically small. Model outcomes were driven by HF hospitalization cost and least influenced by edema ED visit cost. A limitation was that the Clinformatics Data Mart data extract may differ from the original work.

Epidemiology and risk factors for hyperkalaemia in heart failure

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

Development and Validation of an Interpretable Machine Learning Model for Early Prognosis Prediction in ICU Patients with Malignant Tumors and Hyperkalemia

This study aims to develop and validate a machine learning (ML) predictive model for assessing mortality in patients with malignant tumors and hyperkalemia (MTH). We extracted data on patients with MTH from the Medical Information Mart for Intensive Care-IV, version 2.2 (MIMIC-IV v2.2) database. The dataset was split into a training set (75%) and a validation set (25%). We used the Least Absolute Shrinkage and Selection Operator (LASSO) regression to identify potential predictors, which included clinical laboratory indicators and vital signs. Pearson correlation analysis tested the correlation between predictors. In-hospital death was the prediction target. The Area Under the Curve (AUC) and accuracy of the training and validation sets of 7 ML algorithms were compared, and the optimal 1 was selected to develop the model. The calibration curve was used to evaluate the prediction accuracy of the model further. SHapley Additive exPlanations (SHAP) and Local Interpretable Model-agnostic Explanations (LIME) enhanced model interpretability. 496 patients with MTH in the Intensive Care Unit (ICU) were included. After screening, 17 clinical features were included in the construction of the ML model, and the Pearson correlation coefficient was <0.8, indicating that the correlation between the clinical features was small. eXtreme Gradient Boosting (XGBoost) outperformed other algorithms, achieving perfect scores in the training set (accuracy: 1.000, AUC: 1.000) and high scores in the validation set (accuracy: 0.734, AUC: 0.733). The calibration curves indicated good predictive calibration of the model. SHAP analysis identified the top 8 predictive factors: urine output, mean heart rate, maximum urea nitrogen, minimum oxygen saturation, minimum mean blood pressure, maximum total bilirubin, mean respiratory rate, and minimum pH. In addition, SHAP and LIME performed in-depth individual case analyses. This study demonstrates the effectiveness of ML methods in predicting mortality risk in ICU patients with MTH. It highlights the importance of predictors like urine output and mean heart rate. SHAP and LIME significantly enhanced the model's interpretability.

Relationship between Baseline Serum Potassium and 1-Year Readmission in Pediatric Patients with Heart Failure: A Retrospective Cohort Study

Pediatric heart failure (HF) is associated with high readmission rates, but the optimal serum potassium range for this population remains unclear. In this single-center retrospective cohort study, 180 pediatric patients hospitalized for HF between January 2016 and January 2022 were stratified into low-potassium (<3.7 mmol/L), middle-potassium (3.7-4.7 mmol/L), and high-potassium (≥4.7 mmol/L) groups based on the distribution of potassium levels in the study population. The primary outcome was readmission for HF within 1 year of discharge. Cox regression and restricted cubic spline models were used to assess the association between potassium levels and 1-year HF readmission rates. Notably, 38.9% of patients underwent 1 or more 1-year readmissions for HF within 1 year. The high-potassium group had a significantly higher readmission frequency than the middle-potassium group. In multivariate Cox regression models, potassium levels of ≥4.7 mmol/L were independently associated with increased 1-year readmission risk. A J-shaped relationship was observed between baseline potassium levels and 1-year readmission risk, with the lowest risk at 4.1 mmol/L. In pediatric patients with HF, a serum potassium level ≥ 4.7 mmol/L was independently associated with increased 1-year readmission risk. Maintaining potassium levels within a narrow range may improve outcomes in this population.

Hyperkalemia Recurrence Following Medical Nutrition Therapy in Patients with Stage 3-4 Chronic Kidney Disease: The REVOLUTIONIZE I Real-World Study

INTRODUCTION

The REVOLUTIONIZE I study aimed to characterize the relationships between medical nutrition therapy (MNT) and hyperkalemia recurrence in patients with stage 3-4 chronic kidney disease (CKD) and hyperkalemia who received MNT in real-world clinical practice.

METHODS

This observational cohort study used de-identified electronic health record data from patients aged ≥ 18 years with stage 3-4 CKD who received MNT between January 2019 and October 2022 and had hyperkalemia (serum potassium > 5.0 mmol/L) within 30 days before MNT. Patients were followed for 6 months or until the first censoring event (death, prescription of outpatient potassium binder, or study end). The primary outcome was the percentage of patients with ≥ 1 hyperkalemia recurrence during follow-up. Secondary outcomes included the number of hyperkalemia recurrences per patient, time to each recurrence, and hyperkalemia-related healthcare resource utilization. Exploratory outcomes included all-cause healthcare resource utilization and mortality.

RESULTS

The final cohort comprised 2048 patients; 1503 (73.4%) patients remained uncensored after 6 months. During the 6-month follow-up period, 56.0% of patients had ≥ 1 hyperkalemia recurrence and 37.4% had ≥ 1 recurrence within the first month. Patients with ≥ 1 hyperkalemia recurrence during follow-up had a mean ± standard deviation (SD) of 2.6 ± 2.2 recurrences. The mean ± SD time to first hyperkalemia recurrence was 45 ± 46 days; the time between recurrences decreased with subsequent episodes. Hyperkalemia-related hospitalizations and emergency department visits were recorded for 13.7% and 1.5% of patients, respectively. Sensitivity analyses showed that results were consistent across patient subgroups, including those with comorbid heart failure and patients receiving renin-angiotensin-aldosterone system inhibitor therapy at baseline.

CONCLUSION

Most patients with stage 3-4 CKD had hyperkalemia recurrence, and MNT alone was inadequate to prevent recurrence. These patients may require additional long-term treatment, such as novel potassium binders, to maintain normokalemia and prevent hyperkalemia recurrence following MNT. Infographic available for this article. INFOGRAPHIC.

Risk factors for ventricular arrhythmias after emergency percutaneous coronary intervention in elderly patients with acute myocardial infarction

OBJECTIVE

To explore the risk factors for ventricular arrhythmia after percutaneous coronary intervention (PCI) in elderly patients with acute myocardial infarction (AMI).

METHODS

A retrospective cohort of 201 elderly AMI patients who underwent PCI in the emergency department of No. 215 Hospital of Shaanxi Nuclear Industry from April 2020 to January 2023 was analyzed. The patients were randomly divided into a training set (n=134) for model development and a test set (n=67) for model validation. The training set was divided into a ventricular arrhythmia group (n=51) and a non-ventricular arrhythmia group (n=83), based on the occurrence of ventricular arrhythmia post-PCI. The factors affecting ventricular arrhythmias were analyzed by logistic regression and Lasso regression models.

RESULTS

Lasso regression screened 12 characteristic factors at λ=0.1 se. In the training set, the area under the ROC curve (AUC) of the Lasso model for predicting ventricular arrhythmia was 0.954, which was significantly higher than 0.826 for the Logistic model (P < 0.001). In the test set, the AUC of the Lasso model was 0.962, which was also significantly higher than 0.825 for the Logistic model (P=0.003).

CONCLUSION

Compared to the logistic regression model, the Lasso regression model can more accurately predict the occurrence of ventricular arrhythmia after PCI in elderly AMI patients. The Lasso regression model constructed in this study can provide a reference for the clinical identification of high-risk elderly AMI patients and the development of targeted monitoring and treatment.

The unexplored role of alkali and alkaline earth elements (ALAEs) on the structure, processing, and biological effects of bioactive glasses

Bioactive glass has been employed in several medical applications since its inception in 1969. The compositions of these materials have been investigated extensively with emphasis on glass network formers, therapeutic transition metals, and glass network modifiers. Through these experiments, several commercial and experimental compositions have been developed with varying chemical durability, induced physiological responses, and hydroxyapatite forming abilities. In many of these studies, the concentrations of each alkali and alkaline earth element have been altered to monitor changes in structure and biological response. This review aims to discuss the impact of each alkali and alkaline earth element on the structure, processing, and biological effects of bioactive glass. We explore critical questions regarding these elements from both a glass science and biological perspective. Should elements with little biological impact be included? Are alkali free bioactive glasses more promising for greater biological responses? Does this mixed alkali effect show increased degradation rates and should it be employed for optimized dissolution? Each of these questions along with others are evaluated comprehensively and discussed in the final section where guidance for compositional design is provided.

Management of hyperkalemia in children

PURPOSE OF REVIEW

Hyperkalemia is a potentially fatal electrolyte abnormality with no standardized management. The purpose of this review is to provide the knowledge needed for timely and effective management of hyperkalemia in children. It describes the utility of existing and novel therapies.

RECENT FINDINGS

Two newer oral potassium binding agents, patiromer sorbitex calcium and sodium zirconium cyclosilicate, have been FDA-approved for the management of hyperkalemia in adults. These newer agents offer hope for improved management, even though their use in pediatric patients requires further exploration.

SUMMARY

This review highlights the causes and life-threatening effects of hyperkalemia and provides a comprehensive overview of the management of hyperkalemia in both acute and chronic settings along with upcoming treatment strategies.

Impact of Abnormal Potassium on Arrhythmia Risk During Pediatric Digoxin Therapy

Digoxin is used in children with heart failure and tachyarrhythmia. Its use in patients with single ventricle anatomy has increased following evidence of improved interstage survival after the Norwood procedure. Digoxin has a narrow therapeutic window and may alter serum potassium balance, inducing arrhythmias. We hypothesized digoxin use in the setting of abnormal serum potassium levels is associated with arrhythmias. We reviewed all patients ≤ 18 years who received digoxin while admitted at our institution from 2014 to 2021. Admissions < 2 nights were excluded. We compared patients with a hemodynamically significant arrhythmia to those without. We performed adjusted mixed-effects logistic regression with arrhythmia as the outcome variable and potassium status as the predictor variable; adjusting for weight, route of digoxin administration, digoxin indication, serum creatinine, and number of interacting drugs prescribed. Abnormal potassium was defined as serum levels < 3.5 mmol/L or > 6.0 mmol/L. There were 268 encounters in 171 patients. Potassium levels were abnormal in 75.5% of patients who experienced an arrhythmia during digoxin administration, compared to 42.6% who did not (p < 0.001). Odds of arrhythmia was 138% higher in patients with abnormal potassium receiving digoxin (AOR = 2.38, 95% CI 1.07-5.29, p = 0.03). Receiving intravenous digoxin was also associated with a 7.35 odds of cardiac arrhythmia (AOR 7.35, p = 0.006, 95% CI 1.79-30.26). Odds of arrhythmia is increased during digoxin administration when pediatric patients have abnormal potassium levels. Vigilant attention to potassium levels is essential to prevent adverse outcomes during digoxin therapy.

Managing hyperkalemia in patients with heart failure on guideline-directed medical therapy: challenges and opportunities

Heart failure is a chronic and invalidating syndrome that affects tens of millions of people worldwide with significant socio-economic ramifications for the health care systems. Significant progress in the understanding of the pathophysiology of heart failure has allowed the gradual introduction of several drug classes for the management of such patients. Beta-blockers, mineralocorticoid receptor antagonists, angiotensin receptor neprilysin inhibitors, and sodium-glucose-cotransporter 2 inhibitors are all considered pillars of the guideline-directed medical therapy for heart failure. Despite remarkable improvements in the morbidity and mortality of heart failure, however, many patients still develop clinically significant hyperkalemia during combined treatment with those four pharmacological pillars. The consequence is often a down-titration or discontinuation of one or more crucial drugs, which in turns leads to a considerable increase in the risk of cardiovascular events, dialysis, and all-cause mortality. This paper will explore novel approaches for the management of hyperkalemia in heart failure, including closer monitoring of potassium levels, early review of drugs that might increase the risk of hyperkalemia, and pharmacological treatment of hyperkalemia, with a special emphasis on sodium-glucose-cotransporter 2 inhibitors and potassium-binding agents, including patiromer and sodium zirconium cyclosilicate.

Hyperkalemia Recurrence and Its Association With Race and Ethnicity in United States Veterans: A Retrospective Cohort Study

INTRODUCTION

Information on whether race and ethnicity are associated with a greater risk of recurrent hyperkalemia is limited. The aim of this study was to examine the association between race or ethnicity and recurrent hyperkalemia in a population of US veterans.

METHODS

This retrospective study used the US Veterans Affairs database to identify adults (aged ≥18 years) with at least one serum potassium measurement during the study period who ever experienced hyperkalemia (serum potassium > 5.0 mmol/L). The proportion of patients with hyperkalemia recurrence (≥1 subsequent event) within one year was determined for different race and ethnicity groups. The association between patient race and ethnicity and the risk of hyperkalemia recurrence within one year after the index hyperkalemia event was analyzed using competing risk regression.

RESULTS

Among a total of 1,493,539 veterans with incident hyperkalemia (median age (interquartile range): 61.0 years (54.0, 71.0)), recurrence within one year occurred in 19.1% of Black, 16.0% of Native Hawaiian/other Pacific Islander, 15.1% of White, 14.9% of American Indian/Alaska Native, and 13.1% of Asian patient groups. Recurrent hyperkalemia occurred in 18.1% of Hispanic and 15.6% of non-Hispanic patient groups. In a fully-adjusted regression model, recurrent hyperkalemia risk was significantly higher in Black versus White patient groups (subhazard ratio (sHR), 1.17; 95% confidence interval (CI), 1.16-1.19; p< 0.0001) and in Hispanic versus non-Hispanic patient groups (sHR, 1.30; 95% CI, 1.28-1.33; p< 0.0001).

DISCUSSION/CONCLUSION

Among US veterans with incident hyperkalemia, the risk of recurrent hyperkalemia was higher in Black and Hispanic patient groups. This information may be useful for health system screenings to risk stratify patient groups and both guide the frequency of serum potassium monitoring and better understand the root causes of group differences.

Non-steroidal mineralocorticoid antagonists and hyperkalemia monitoring in chronic kidney disease patients associated with type II diabetes: a narrative review

Chronic kidney disease (CKD) is a prevalent complication of Type II diabetes (T2D). The coexistence of CKD with T2D is comparable to cardiovascular disease (CVD) when the estimated glomerular filtration rate declines below 60 ml/min/1.73 m2. Screening and early detection of people with high risk for CKD would be beneficial in managing CKD progress and the associated complications such as CV complications. Renin-angiotensin-aldosterone system inhibitors (RAASi) have demonstrated beneficial effects in delaying CKD progression, but they carry the risk of hyperkalemia. Nonsteroidal mineralocorticoid antagonists (nsMRA), such as finerenone, exhibit considerable efficacy in their anti-inflammatory, antifibrotic, and renal protective effects with demonstrable reductions in CV complications. In addition, nsMRAs do not cause significant changes in serum potassium levels compared to traditional steroidal MRA. Ongoing research explores the capacity of the sodium-glucose transport protein 2 inhibitors (SGLT-2i), combined with nsMRA, to produce synergistic renal protective effects and reduce the risk of hyperkalemia. Also, a dedicated renal outcomes study (FLOW study) involving a once-weekly injectable Glucagon-like peptide-1 receptor agonist, semaglutide, was halted early by the data monitoring committee due to having achieved the predefined efficacy endpoint and considerations related to renal disease. In CKD patients with T2D on nsMRA, hyperkalemia management requires a comprehensive approach involving lifestyle adjustments, dietary modifications, regular serum potassium level monitoring, and potassium binders, if necessary. Withholding or down-titration of nsMRAs with close monitoring of serum potassium levels may be required in patients with concerning potassium levels. In light of the current state of knowledge, this review article explores the perspectives and approaches that HCPs may consider when monitoring and managing hyperkalemia in CKD patients with T2D.

Salt Sensitivity: Causes, Consequences, and Recent Advances

Salt (sodium chloride) is an essential nutrient required to maintain physiological functions. However, for most people, daily salt intake far exceeds their physiological need and is habitually greater than recommended upper thresholds. Excess salt intake leads to elevation in blood pressure which drives cardiovascular morbidity and mortality. Indeed, excessive salt intake is estimated to be responsible for ≈5 million deaths per year globally. For approximately one-third of otherwise healthy individuals (and >50% of those with hypertension), the effect of salt intake on blood pressure elevation is exaggerated; such people are categorized as salt sensitive and salt sensitivity of blood pressure is considered an independent risk factor for cardiovascular disease and death. The prevalence of salt sensitivity is higher in women than in men and, in both, increases with age. This narrative review considers the foundational concepts of salt sensitivity and the underlying effector systems that cause salt sensitivity. We also consider recent updates in preclinical and clinical research that are revealing new modifying factors that determine the blood pressure response to high salt intake.

Phosphate Restriction Prevents Metabolic Acidosis and Curbs Rise in FGF23 and Mortality in Murine Folic Acid-Induced AKI

SIGNIFICANCE STATEMENT

Patients with AKI suffer a staggering mortality rate of approximately 30%. Fibroblast growth factor 23 (FGF23) and phosphate (P i ) rise rapidly after the onset of AKI and have both been independently associated with ensuing morbidity and mortality. This study demonstrates that dietary P i restriction markedly diminished the early rise in plasma FGF23 and prevented the rise in plasma P i , parathyroid hormone, and calcitriol in mice with folic acid-induced AKI (FA-AKI). Furthermore, the study provides evidence for P i -sensitive osseous Fgf23 mRNA expression and reveals that P i restriction mitigated calciprotein particles (CPPs) formation, inflammation, acidosis, cardiac electrical disturbances, and mortality in mice with FA-AKI. These findings suggest that P i restriction may have a prophylactic potential in patients at risk for AKI.

BACKGROUND

In AKI, plasma FGF23 and P i rise rapidly and are independently associated with disease severity and outcome.

METHODS

The effects of normal (NP) and low (LP) dietary P i were investigated in mice with FA-AKI after 3, 24, and 48 hours and 14 days.

RESULTS

After 24 hours of AKI, the LP diet curbed the rise in plasma FGF23 and prevented that of parathyroid hormone and calcitriol as well as of osseous but not splenic or thymic Fgf23 mRNA expression. The absence of Pth prevented the rise in calcitriol and reduced the elevation of FGF23 in FA-AKI with the NP diet. Furthermore, the LP diet attenuated the rise in renal and plasma IL-6 and mitigated the decline in renal α -Klotho. After 48 hours, the LP diet further dampened renal IL-6 expression and resulted in lower urinary neutrophil gelatinase-associated lipocalin. In addition, the LP diet prevented the increased formation of CPPs. Fourteen days after AKI induction, the LP diet group maintained less elevated plasma FGF23 levels and had greater survival than the NP diet group. This was associated with prevention of metabolic acidosis, hypocalcemia, hyperkalemia, and cardiac electrical disturbances.

CONCLUSIONS

This study reveals P i -sensitive FGF23 expression in the bone but not in the thymus or spleen in FA-AKI and demonstrates that P i restriction mitigates CPP formation, inflammation, acidosis, and mortality in this model. These results suggest that dietary P i restriction could have prophylactic potential in patients at risk for AKI.

Abrupt Decline in Estimated Glomerular Filtration Rate after Initiating Sodium-Glucose Cotransporter 2 Inhibitors Predicts Clinical Outcomes: A Systematic Review and Meta-Analysis

BACKGRUOUND

The initiation of sodium-glucose cotransporter-2 inhibitors (SGLT2i) typically leads to a reversible initial dip in estimated glomerular filtration rate (eGFR). The implications of this phenomenon on clinical outcomes are not well-defined.

METHODS

We searched MEDLINE, Embase, and Cochrane Library from inception to March 23, 2023 to identify randomized controlled trials and cohort studies comparing kidney and cardiovascular outcomes in patients with and without initial eGFR dip after initiating SGLT2i. Pooled estimates were calculated using random-effect meta-analysis.

RESULTS

We included seven studies in our analysis, which revealed that an initial eGFR dip following the initiation of SGLT2i was associated with less annual eGFR decline (mean difference, 0.64; 95% confidence interval [CI], 0.437 to 0.843) regardless of baseline eGFR. The risk of major adverse kidney events was similar between the non-dipping and dipping groups but reduced in patients with a ≤10% eGFR dip (hazard ratio [HR], 0.915; 95% CI, 0.865 to 0.967). No significant differences were observed in the composite of hospitalized heart failure and cardiovascular death (HR, 0.824; 95% CI, 0.633 to 1.074), hospitalized heart failure (HR, 1.059; 95% CI, 0.574 to 1.952), or all-cause mortality (HR, 0.83; 95% CI, 0.589 to 1.170). The risk of serious adverse events (AEs), discontinuation of SGLT2i due to AEs, kidney-related AEs, and volume depletion were similar between the two groups. Patients with >10% eGFR dip had increased risk of hyperkalemia compared to the non-dipping group.

CONCLUSION

Initial eGFR dip after initiating SGLT2i might be associated with less annual eGFR decline. There were no significant disparities in the risks of adverse cardiovascular outcomes between the dipping and non-dipping groups.

Potassium homeostasis and therapeutic intervention with sodium zirconium cyclosilicate: A model-informed drug development case study

Potassium (K+ ) is the main intracellular cation in the body. Elevated K+ levels (hyperkalemia) increase the risk of life-threatening arrhythmias and sudden cardiac death. However, the details of K+ homeostasis and the effects of orally administered K+ binders, such as sodium zirconium cyclosilicate (SZC), on K+ redistribution and excretion in patients remain incompletely understood. We built a fit-for-purpose systems pharmacology model to describe K+ homeostasis in hyperkalemic subjects and capture serum K+ (sK+ ) dynamics in response to acute and chronic administration of SZC. The resulting model describes K+ distribution in the gastrointestinal (GI) tract, blood, and extracellular and intracellular spaces of tissue, renal clearance of K+ , and K+ -SZC binding and excretion in the GI tract. The model, which was fit to time-course sK+ data for individual patients from two clinical trials, accounts for bolus delivery of K+ in meals and oral doses of SZC. The virtual population of patients derived from fitting the model to these trials was then modified to predict the SZC dose-response and inform clinical trial design in two new applications: emergency lowering of sK+ in severe hyperkalemia and prevention of hyperkalemia between dialysis sessions in patients with end-stage chronic kidney disease. In both cases, the model provided novel and useful insight that was borne out by the now completed clinical trials, providing a concrete case study of fit-for-purpose, model-informed drug development after initial approval of a drug.

Machine learning models for early prediction of potassium lowering effectiveness and adverse events in patients with hyperkalemia

The aim of this study was to develop a model for early prediction of adverse events and treatment effectiveness in patients with hyperkalemia. We collected clinical data from patients with hyperkalemia in the First Hospital of Zhejiang University School of Medicine between 2015 and 2021. The least absolute shrinkage and selection operator (LASSO) and multivariate logistic regression were used to analyze the predictors on the full dataset. We randomly divided the data into a training group and a validation group, and used LASSO to filter variables in the training set. Six machine learning methods were used to develop the models. The best model was selected based on the area under the curve (AUC). Shapley additive exPlanations (SHAP) values were used to explain the best model. A total of 1074 patients with hyperkalemia were finally enrolled. Diastolic blood pressure (DBP), breathing, oxygen saturation (SPO2), Glasgow coma score (GCS), liver disease, oliguria, blood sodium, international standardized ratio (ISR), and initial blood potassium were the predictors of the occurrence of adverse events; peripheral edema, estimated glomerular filtration rate (eGFR), blood sodium, actual base residual, and initial blood potassium were the predictors of therapeutic effect. Extreme gradient boosting (XGBoost) model achieved the best performance (adverse events: AUC = 0.87; therapeutic effect: AUC = 0.75). A model based on clinical characteristics was developed and validated with good performance.

Relationship between a diagnosis of kidney failure and heart diseases in patients with hyperkalemia

OBJECTIVES

This study seeks to determine the association between kidney failure and heart diseases by examining how they influence the diagnosis of hyperkalemia.

METHODS

We employ a fuzzy regression discontinuity design (RDD) by harnessing the inherent threshold in potassium levels, which serves as a diagnostic criterion for hyperkalemia. Simultaneously, we utilize patient diagnosis data related to kidney failure and heart diseases. This approach allows us to evaluate the causal impact of both diagnoses on hyperkalemia.

RESULTS

Significant overall increases in the risk of developing hyperkalemia are evident subsequent to a diagnosis of kidney failure or heart disease. The study finds that the probability of receiving a kidney failure diagnosis increases by 11.2% regarding a cut-off of 6 mEq/L of potassium. In addition, there is a 6.8% likelihood of experiencing hyperkalemia in the case of a prior diagnosis of hypertension, and an 8.8% probability in the case of a diagnosis of depression. The findings remain robust when considering alternative parametric and non-parametric specifications as well as placebo tests.

CONCLUSIONS

This study provides new empirical insights into the causal impact of kidney failure and heart disease, underscoring the significance of monitoring such patients to prevent serious complications in the future.

K+ontrol rapidly and efficiently reduces potassium in donor blood during ex vivo circulation

BACKGROUND

Patients with kidney failure are at risk for lethal complications from hyperkalemia. Resuscitation, medications, and hemodialysis are used to mitigate increased potassium (K+) levels in circulating blood; however, these approaches may not always be readily available or effective, especially in a resource limited environment. We tested a sorbent cartridge (KC, K+ontrol CytoSorbents Medical Inc., Monmouth Junction, New Jersey) which contains a resin adsorber for K+. The objective of this study was to test the utility of KC in an ex vivo circulation system. We hypothesized that KC reduces K+ levels in extracorporeal circulation of donor swine whole blood infused with KCl.

METHODS

A six-hour circulation study was carried out using KC, a NxStage (NxStage Medical, Inc., Lawrence, MA) membrane, blood bag containing heparinized whole blood with KCl infusion, 3/16-inch ID tubing, a peristaltic pump, and flow sensors. The NxStage permeate line was connected back to the main circuit in the Control group (n = 6), creating a recirculation loop. For KC group (n = 6), KC was added to the recirculation loop, and a continuous infusion of KCl at 10 mEq/hour was administered for two hours. Blood samples were acquired at baseline and every hour for 6 h.

RESULTS

In the control group, K+ levels remained at ∼9 mmol/L; 9.1 ± 0.4 mmol/L at 6 h. In the KC group, significant decreases in K+ at hour 1 (4.3 ± 0.3 mmol/L) and were sustained for the experiment duration equilibrating at 4.6 ± 0.4 mmol/L after 6 h (p = 0.042). Main loop blood flow was maintained under 400 mL/min; recirculation loop flow varied between 60 and 70 mL/min in the control group and 45-55 mL/min in the KC group. Decreases in recirculation loop flow in KC group required 7% increase of pump RPM.

CONCLUSIONS

During ex-vivo extracorporeal circulation using donor swine blood, KC removed approximately 50% of K+, normalizing circulating levels.

Hyperkalemia: Pharmacotherapies and Clinical Considerations

Hyperkalemia has been defined as a condition where a serum potassium level is >5.5 mmol/l. It is associated with fatal dysrhythmias and muscular dysfunction. Certain medical conditions, such as chronic kidney disease (CKD), diabetes mellitus, and others, can lead to hyperkalemia. Many of the signs of hyperkalemia are nonspecific. A history and physical examination can be beneficial in the diagnosis of the condition. In this regard, certain characteristic electrocardiogram findings are associated with hyperkalemia along with laboratory potassium levels. In acute and potentially lethal conditions, hyperkalemia treatments include glucose and insulin, bicarbonate, calcium gluconate, beta-2 agonists, hyperventilation, and dialysis. There are several drugs, both old and new, that can additionally aid in the reduction of serum potassium levels. The present investigation evaluated some of these different drugs, including sodium polystyrene sulfonate (SPS), sodium zirconium cyclosilicate (SZC), and patiromer. These drugs each have increased selectivity for potassium and work primarily in the gastrointestinal (GI) tract. Each of these medications has unique benefits and contraindications. Clinicians must be aware of these medications when managing patients with hyperkalemia.

INTRACOLON COOLING INCREASES SURVIVAL RATE IN THE RAT MODEL OF LETHAL HEMORRHAGE

ABSTRACT

Background: The objective of this study was to investigate whether transrectal intracolon (TRIC) cooling can prolong the survival duration in a rat hemorrhagic shock (HS) model. Methods: A lethal HS was induced by bleeding 47% of the total blood volume. A TRIC device was placed into the colon to maintain the intracolon temperature either at 37°C (TRIC37) or at 10°C (TRIC10) post-HS. In the surface cooling (SC) rats, the body temperatures were maintained at the same level as the esophageal temperature of the TRIC10 rats. A separated group of TRIC10 rats were resuscitated (Res) at 90 min post-HS. A total of six groups were as follows: (i) Sham TRIC37 (n = 5), (ii) Sham TRIC10 (n = 5), (iii) HS TRIC37 (n = 5), (iv) HS TRIC10 (n = 6), (v) HS SC (n = 6), and (vi) HS TRIC10 + Res (n = 6). Results: An average post-HS survival time was 18.4 ± 9.4 min in HS TRIC37 and 82 ± 27.82 min in the HS SC group. In striking contrast, the HS TRIC10 group exhibited an average survival time of 150.2 ± 66.43 min. The post-HS blood potassium level rose significantly in the HS TRIC37 and HS SC, whereas it remained unchanged in the TRIC10 groups. Post-HS intestinal damage occurred in HS TRIC37 and HS SC groups but virtually absent in HS TRIC10 groups. After resuscitation at 90 min post-HS, all HS TRIC10 rats were fully recovered from the lethal HS. Conclusions: TRIC10 reversed the high blood potassium level, prevented the intestinal damage, and prolonged the survival duration by sixfold relative to normothermia and by twofold compared with SC post-HS. All TRIC10 rats were successfully resuscitated at 90 min post-HS.

Association of serum potassium level with dietary potassium intake in Chinese older adults: a multicentre, cross-sectional survey

OBJECTIVES

Evidence linking dietary potassium and serum potassium is virtually scarce and inconclusive. The aim of the study was to investigate the association between serum potassium level and potassium intake measured by 24-hour urine. We also explored whether the association differed across health conditions.

DESIGN

A cross-sectional study conducted from September 2017 to March 2018.

SETTING

48 residential elderly care facilities in northern China.

PARTICIPANTS

Participants aged 55 years and older and with both serum potassium and 24-hour urinary potassium measured were classified as having a low (apparently healthy), moderate (with ≥1 health condition but normal renal function) and high (with ≥1 health condition and abnormal renal function) risk of hyperkalaemia.

EXPOSURE

Potassium intake is measured by 24-hour urinary potassium.

OUTCOMES

Serum potassium in association with potassium intake after adjustment for age, sex, region and accounting for the cluster effect.

RESULTS

Of 962 eligible participants (mean age 69.1 years, 86.8% men), 17.3% were at low risk, 48.4% at moderate risk and 34.3% at high risk of hyperkalaemia. Serum potassium was weakly associated with 24-hour urinary potassium among individuals with moderate (adjusted β=0.0040/L; p=0.017) and high (adjusted β=0.0078/L; p=0.003) but not low (adjusted β=0.0018/L; p=0.311) risk of hyperkalaemia.

CONCLUSIONS

A weak association between dietary potassium intake and serum potassium level existed only among individuals with impaired renal function or other health conditions but not among apparently healthy individuals. The results imply that increasing dietary potassium intake may slightly increase the risk of hyperkalaemia but may also decrease the risk of hypokalaemia in unhealthy individuals, both of which have important health concerns.

TRIAL REGISTRATION NUMBER

NCT03290716; Post-results.

Pharmacotherapy considerations with finerenone in the treatment of chronic kidney disease associated with type 2 diabetes

PURPOSE

This review provides an overview of the management of chronic kidney disease (CKD) associated with type 2 diabetes (T2D), how the novel treatment class of nonsteroidal mineralocorticoid receptor antagonists (MRAs) fits within the treatment landscape, and how pharmacists can contribute to the multidisciplinary care of patients with CKD associated with T2D.

SUMMARY

Optimizing pharmacotherapy for patients with CKD associated with T2D is critical to prevent or slow progression to end-stage kidney disease and reduce the incidence of cardiovascular events. However, many patients with CKD receive suboptimal treatment, in part because of the high complexity of care required, a lack of disease recognition among providers and patients, and a failure to utilize new kidney-protective therapies. Finerenone is the first nonsteroidal, selective MRA to be approved by the US Food and Drug Administration and the European Medicines Agency for the treatment of adult patients with CKD associated with T2D. Clinical trials have demonstrated that finerenone significantly reduces the risk of cardiorenal disease progression vs placebo and has a reduced risk of hyperkalemia compared to traditional steroidal MRAs. Initiation of finerenone should follow evaluation of baseline estimated glomerular filtration rate and serum potassium levels. Consideration of potential drug-drug interactions, follow-up monitoring of potassium levels, and coordination of changes in pharmacotherapy across the patient care team are also important.

CONCLUSION

Finerenone is a valuable addition to the treatment landscape for CKD associated with T2D. Through their expertise in -medication -management, transitions of care, and patient education, clinical pharmacists are well positioned to ensure patients receive safe and effective -treatment.

National Initiatives on Salt Substitutes: Scoping Review

BACKGROUND

Salt substitutes are edible salts that contain less sodium chloride owing to its partial substitution with other minerals, which serve as an important and effective intervention and public health strategy targeting hypertension and its secondary diseases, despite a small degree of controversy.

OBJECTIVE

This study aimed to identify the current salt substitute initiatives in various nations and intergovernmental organizations (IGOs) worldwide and summarize their types and characteristics.

METHODS

A scoping review was performed based on Arksey and O'Malley's framework and the latest guidance from the Joanna Briggs Institute. Searches were conducted on Google; government websites on food, health, and other related topics; PubMed; Web of Science; and Google Scholar from January 2022 to May 2022. Initiatives related to salt substitutes that were included in the study focused on the involvement of governments or IGOs through the publication of standards, actions, collaborations, funding, and so on. Data were extracted into Microsoft Excel (version 2019; Microsoft Corp) based on predefined items and analyzed using narrative synthesis and frequency count methods.

RESULTS

A total of 35 initiatives from 11 countries (of which 9 are high-income countries) and 3 IGOs were identified. We classified all salt substitute initiatives into 5 types, namely benefit-risk assessments and cautions; plans and actions; regulations and standards; labels; and food reformulation, cooperation with the food industry, and media. More than half (18/35, 51%) of the salt substitute initiatives were launched within the past 5 years. Except for regulations and standards, salt substitute initiatives are, in general, part of the salt reduction framework. No nation or IGO has yet reported on the monitoring and implications of the use of salt substitutes.

CONCLUSIONS

Despite the limited number of salt substitute initiatives worldwide at present, a review on the different types and characteristics of such initiatives could be helpful in providing a reference for policy makers and stakeholders. Given the great potential of salt substitutes in improving hypertension and stroke, we call on more nations to pay attention to these substitutes and propose salt substitute initiatives in line with their national conditions.

Sodium bicarbonate and salbutamol facilitate recovery from hyperkalemia-induced electrocardiogram abnormalities in bullfrog hearts

Hyperkalemia is a common electrolyte abnormality frequently complicated with chronic kidney disease. By injecting potassium chloride (KCl) solutions intravenously into bullfrogs, we reproduced typical electrocardiogram (ECG) abnormalities of hyperkalemia in the frog hearts, such as the peaked T waves and the widening of QRS complexes. Simultaneous recordings of cardiac action potentials showed morphological changes that synchronized with those of ECG. After 100 mM KCl injection, the widened QRS complexes continued for a while and gradually restored to their baseline widths. However, pre-treatment with sodium bicarbonate or salbutamol, which directly or indirectly stimulates Na+/K+-ATPase activity, significantly facilitated the recovery from the widened QRS duration, indicating the transcellular movement of potassium ions from the extracellular fluid into the intracellular stores.

Capillary electrophoresis in parenteral nutrition control - validation of two analytical methods: Amino acids/glucose/glucose-1-phosphate and K/Na/Ca/Mg

OBJECTIVES

Production of parenteral nutrition bags (PNBs) involves many nutrients: complete control of the production process decreases the risk of error. This study aimed to develop and validate two analytical methods by capillary electrophoresis (CE) for simultaneous detection of: glucose, amino acids (Primene®) and glucose-1-phosphate (Phocytan®) (anionic method, AM) on one hand; and on the other hand potassium, sodium, calcium and magnesium (cationic method, CM).

METHODS

Methods were developed using capillary electrophoresis with diode array detection (CE-DAD) (CE 7100, Agilent), indirect photometric detection, 56 cm long capillary and two different buffers (pH=12.1 for AM and pH=3.2 for CM). These methods were validated according to guidelines from the Société Française des Sciences et Techniques Pharmaceutiques (SFSTP).Analytical parameters were optimised: temperature was regulated at 15°C and the current settled to - 15kV, for a 21 minute analysis time for AM. Conditions were settled to 25°C and 30kV for CM so the analysis time dropped to 7 minutes.Accuracy profiles were established and recovery rates (RR), Repeatability and Reproducibility Coefficient of Variation (respectively RaCV and RoCV) were calculated.Capability was also calculated for each nutrient and concentration range according to guidelines from the Evaluation and Research Group on Protection in a Controlled Atmosphere (GERPAC).

RESULTS

Methods were successfully validated with: RR between 99.2 and 101.9%, RaCV between 1.5 and 3.1%, and RoCV between 2.4 and 4.1% for AM, and RR between 97.5 and 102.7%, RaCV between 0.5 and 2.3%, and RoCV between 0.6 and 2.8% for CM.Accuracy profiles were established with 95% β probability, except for glucose-1-phosphate (90%). Acceptance limits were settled to ±1 0% of target value. Capabilities are defined as "good" or "very good".

CONCLUSIONS

The methods developed by this research will ensure the composition of PNB is compliant to PNB formulas. These results show CE is an appropriate method for PNB quantitative control.CE utilisation for controlling other hospital preparations seems to be a relevant alternative to conventional methods such as liquid chromatography.