Prevalence, clinical impact and costs of hyperkalaemia: Special focus on heart failure

Pseudohyperkalemia in pediatric patients with newly diagnosed hematological malignancies

Patients with newly diagnosed hematological malignancies often present with a considerable cellular burden, leading to complications including hyperkalemia. However, pseudohyperkalemia, arising from in vitro cell lysis, can pose challenges in clinical practice. Although pseudohyperkalemia is frequently reported in adult hematological malignancies, its occurrence in pediatric patients is underreported, and its incidence in this demographic remains unclear. We retrospectively reviewed the medical records of pediatric patients who received a new diagnosis of hematological malignancies from 2011 to 2022 at Taichung Veterans General Hospital. Hyperkalemia was defined by a serum or plasma potassium level exceeding 5.5 mEq/L. Pseudohyperkalemia was defined by 1) a potassium decrease of over 1 mEq/L in within 4 h without intervention or 2) the absence of electrocardiography changes indicative of hyperkalemia. Cases with apparent red blood cell hemolysis were excluded. A total of 157 pediatric patients with a new diagnosis of hematological malignancies were included, 14 of whom exhibited hyperkalemia. Among these 14 cases, 7 cases (4.5%) were of pseudohyperkalemia. This rate increased to 21.2% in patients with initial hyperleukocytosis. Pseudohyperkalemia was associated with a higher initial white blood cell count and lower serum sodium level. All episodes of pseudohyperkalemia occurred in the pediatric emergency department, where samples were obtained as plasma, whereas all true hyperkalemia cases were observed in the ordinary ward or intensive care unit, where samples were obtained as serum. Timely recognition of pseudohyperkalemia is crucial to avoiding unnecessary potassium-lowering interventions in pediatric patients with newly diagnosed hematological malignancies.

Hyperkalemia in chronic kidney disease patients with and without heart failure: an Italian economic modelling study

BACKGROUND

Hyperkalemia (HK) is frequently present in chronic kidney disease (CKD). Risk factors for HK among CKD patients include comorbidities and renin-angiotensin-aldosterone system inhibitor (RAASi) treatment. Current standard of care (SoC) often necessitates RAASi down-titration or discontinuation, resulting in poorer cardiorenal outcomes, hospitalization and mortality. This study evaluates the cost-effectiveness of patiromer for HK in CKD patients with and without heart failure (HF) in an Italian setting.

METHODS

A lifetime Markov cohort model was developed based on OPAL-HK to assess the health economic impact of patiromer therapy in comparison to SoC after accounting for the effects of HK and RAASi use on clinical events. Outcomes included accumulated clinical events, number needed to treat (NNT) and the incremental cost-effectiveness ratio (ICER). Subgroup analysis was conducted in CKD patients with and without HF.

RESULTS

Patiromer was associated with an incremental discounted cost of €4,660 and 0.194 quality adjusted life years (QALYs), yielding an ICER of €24,004. Per 1000 patients, patiromer treatment prevented 275 moderate/severe HK events, 54 major adverse cardiovascular event, 246 RAASi discontinuation and 213 RAASi up-titration/restart. Subgroup analysis showed patiromer was more effective in preventing clinical events in CKD patients with HF compared to those without; QALY gains were greater in CKD patients without HF versus those with HF (0.267 versus 0.092, respectively). Scenario analysis and sensitivity analysis results support base-case conclusions.

CONCLUSION

Patiromer is associated with QALY gains in CKD patients with and without HF compared to SoC in Italy. Patiromer prevented HK events, enabled RAASi therapy maintenance and reduced cardiovascular event risk.

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.

Potassium levels and the risk of all-cause and cardiovascular mortality among patients with cardiovascular diseases: a meta-analysis of cohort studies

BACKGROUND

Abnormal blood potassium levels are associated with an increased risk of cardiometabolic diseases and mortality in the general population; however, evidence regarding the association between dyskalemia and mortality among patients with cardiovascular disease (CVD) remains inconclusive. This study aimed to evaluate the association of potassium levels with all-cause and cardiovascular mortality among patients with CVD.

METHODS

PubMed, Embase, Web of Science, and Cochrane Library databases were searched up to August 2023 to identify relevant cohort studies among patients with CVD, such as myocardial infarction, stroke, and heart failure. Abnormal potassium levels were considered as hypokalemia or hyperkalemia. The primary outcomes were all-cause mortality based on follow-up length (including in-hospital, short-term and long-term mortality) and cardiovascular mortality. The methodological quality of included studies was assessed by using the Newcastle-Ottawa Scale. The pooled relative risks (RRs) and 95% confidence intervals (CIs) were calculated using random-effects models. Restricted cubic splines were applied to explore the dose-response relationship.

RESULTS

Thirty-one cohort studies involving 227,645 participants with an average age of 68.3 years were included in the meta-analysis, all of which achieved moderate to high quality. Hyperkalemia was significantly associated with an approximately 3.0-fold increased risk of all-cause in-hospital mortality (RR:2.78,95CI%:1.92,4.03), 1.8-fold of all-cause short-term mortality (RR:1.80, 95CI%:1.44,2.27), 1.3-fold of all-cause long-term mortality (RR:1.33, 95CI%:1.19,1.48) and 1.2-fold of cardiovascular mortality (RR:1.19, 95CI%:1.04,1.36). Similar positive associations were also observed between hypokalemia and risk of all-cause mortality and cardiovascular mortality. The RRs of all-cause in-hospital, short-term, long-term mortality and cardiovascular mortality with hyperkalemia were attenuated to 2.21 (95CI%:1.60,3.06), 1.46(95CI%:1.25,1.71), 1.23 (95CI%:1.09,1.39) and 1.13 (95CI%:1.00,1.27) when treating hypokalemia together with normokalemia as the reference group. A U-shaped association was observed between potassium levels and mortality, with the lowest risk at around 4.2 mmol/L.

CONCLUSIONS

Both hypokalemia and hyperkalemia were positively associated with the risk of mortality in patients with CVD. Our results support the importance of potassium homeostasis for improving the CVD management.

REGISTRATION

PROSPERO, CRD42022324337.

Italian healthcare resource consumption for patients on hemodialysis treated for chronic kidney disease-associated pruritus (CKD-aP)

Background

Chronic kidney disease-associated pruritus (CKD-aP) affects patients on hemodialysis. This study identified hemodialysis patients presumably affected or not affected by CKD-aP and integrated healthcare costs, from the perspective of the Italian administrative healthcare data.

Methods

Through cross-linkage of Italian administrative healthcare data collected between 2015 and 2017 (accrual period) in the database of Fondazione ReS (Ricerca e Salute), patients undergoing in-hospital/outpatient hemodialysis were selected. Cohorts with and without CKD-aP were created based on the presence/absence of CKD-aP-related treatment (according to common clinical practice and guidelines) supplies and assessed in terms of CKD-aP-related treatments and mean healthcare costs per capita paid by the Italian National Health Service (INHS).

Results

Of 1,239 people on hemodialysis for ≥2 years, CKD-aP affected 218 patients. Patients with CKD-aP were older and with more comorbidities. During the follow-up year, on average, the INHS spent €37,065 per case, €31,286 per control and € 35,988 per non-CKD-aP subject. High-efficiency dialytic therapies performed to people on hemodialysis with CKD-aP largely weighed on the overall mean annual cost.

Conclusions

This real-world study identified patients on chronic hemodialysis potentially treated for CKD-aP. Interestingly, high-efficiency dialysis seems the most frequent and expensive choice for the treatment of CKD-aP. The discovery of appropriate and effective treatments for this condition might offer cost offsets.

Acute myeloid leukemia: Incidence, transplantation and survival through Italian administrative healthcare data

OBJECTIVE

To identify newly diagnosed patients with acute myeloid leukemia in 2017 treated with intensive chemotherapy or unfit for intensive chemotherapy, and to assess their probability of receiving allogeneic stem cell transplantation and survival, from the Italian National Health Service perspective.

PATIENTS AND METHODS

From the Ricerca e Salute database, adults with an in-hospital diagnosis of acute myeloid leukemia (International Classification of Disease-9th version-Clinical Modification code 205.0x) in 2017 (index date), without any identifying acute myeloid leukemia criteria within the preceding year, were selected. Among them, subjects treated with intensive chemotherapy (chemotherapy during an overnight hospitalization) within one year after index date were identified. The remaining were considered unfit for intensive chemotherapy. Gender, age and comorbidities were described. Within the follow-up period, probabilities of in-hospital allogeneic stem cell transplantation and overall survival were assessed through Kaplan Meier analyses.

RESULTS

From 4,840,063 beneficiaries of the Italian National Health Service, 368 newly acute myeloid leukemia diagnosed adults (9.0 *100,000) were selected. Males comprised 57%. Mean age was 68±15. There were 197 patients treated with intensive chemotherapy. The remaining 171 unfit for intensive chemotherapy were older (72±14) and with more comorbidities (e.g. hypertension, chronic lung diseases and chronic kidney disease). Only patients treated with intensive chemotherapy underwent an allogeneic stem cell transplantation (41; 33%) during the one year after the index date. Within the first and second follow-up year, respectively: 41.1% and 26.9% of subjects treated with intensive chemotherapy (144) survived (median survival time: 7.8 months); 25.7% and 18.7% of those unfit for intensive chemotherapy (139) survived (1.2 months). Difference was significant (p<0.0001). Within one and two years after transplantation (41 patients), 73.5% and 67.3% of subjects survived, respectively.

CONCLUSION

This study, by showing the incidence of acute myeloid leukemia in Italy in 2017, the proportion of patients treated with intensive chemotherapy from the new diagnosis, the use of allogeneic stem cell transplantation and two-year survival, integrated evidence on large and unselected populations and may help to improve treatment strategies of older acute myeloid leukemia patients.

Antiplatelet Therapy during the First Year after Acute Coronary Syndrome in a Contemporary Italian Community of over 5 Million Subjects

Background: Patterns of real-world antiplatelet therapy (APT) are reported to differ from guideline recommendations. This study describes patterns of APT during the year following a hospital diagnosis of acute coronary syndrome (ACS) and possible implications in terms of revascularization rates, rehospitalizations, and costs for the Italian National Health Service. Methods: From >5 million people, patients discharged (=index date) with primary/secondary ACS diagnosis in 2017 were identified by cross-linkage of administrative health data collected by the Ricerca e Salute (ReS) Foundation. Patients were characterized by revascularization rates at index date, APT at one month and one year (with appropriate coverage defined as ≥80% of defined daily doses), and rehospitalizations and healthcare costs during follow-up. Results: From the 2017 ReS database, 7966 (1.46 × 1000 inhabitants) were discharged alive with an ACS diagnosis. Most were >69 years and male. Of these, 83% (6640/7966) received ≥1 recommended antiplatelet agent within one month (treated group): 23% (1870/7966) as single and 60% (4770/7966) as dual APT. Among the 53% undergoing revascularization, 81% received dual APT at one month. Of the 78% with the same APT at one year, 66% showed appropriate coverage. For subjects treated and untreated with APT at one month, one-year rehospitalization rates were 54% and 66%, respectively, and mean per capita costs were EUR 14,316 and EUR 16,552, respectively (hospitalization driving >80% of costs). Conclusions: Among survivors of a hospitalized ACS diagnosis, this analysis shows relatively high APT under-treatment at one month and one year, associated with fewer index revascularization rates, more rehospitalizations, and greater costs. Further initiatives to understand undertreatment and poor adherence should lead to improved health management and savings.

Acute lower respiratory infections: real-world evidence of antibiotic prescription pattern and costs from a large administrative Italian database

OBJECTIVE

This observational retrospective analysis aimed to describe antibiotic prescription pattern in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD) and community-acquired pneumonia (CAP) and their costs, from the Italian National Health Service perspective.

METHODS

From the ReS database, a cross-linkage of Italian healthcare administrative databases through a unique anonymous code allowed to select subjects aged ≥12 years, supplied with at least an antibacterial for systemic use (ATC code: J01) from 01/01/2017 to 12/31/2017 and evaluable until the end of 2018. Prescriptions of different antibiotics on the same date were excluded. The prescription pattern was assessed for patients with an AECOPD (aged ≥50) or a CAP event (aged ≥12) in 2017. A 30-day cost analysis after the antibacterial supply and according to absence/presence (15 days before/after the supply) of AECOPD/CAP hospitalization was performed.

RESULTS

In 2017, among patients aged ≥12 (~5 million), 1,845,268 were supplied with ≥1 antibacterial (37.2%). Antibacterial prescriptions potentially related to AECOPD were 39,940 and 4,059 to CAP: quinolones were the most prescribed (37.2% and 39.0%, respectively), followed by third-generation cephalosporins (25.5%; 27.5%), penicillins (15.4%; 14.9%), and macrolides (14.4%; 11.3%); the 30-day mean cost was €709 and €2,889. An association AECOPD/CAP-antibacterial supply costed more when the hospitalization occurred 15 days after the antibiotic supply (€5,006 and €4,966, respectively).

CONCLUSIONS

Findings confirmed the very high use of antimicrobials in Italy and highlighted the urgent need of improving current prescribing practices and developing new molecules, to stop the incessant spread of antimicrobial resistance and related socioeconomic impacts.

Coronary Artery Disease in Patients Older than 35 and Eligible for Cardiovascular Secondary Prevention: An Italian Retrospective Observational Analysis of Healthcare Administrative Databases

Background: This study describes patients with coronary artery disease (CAD) who are eligible for secondary prevention and assesses their healthcare consumption and costs from the perspective of the Italian National Health Service (INHS). Methods: From the Fondazione Ricerca e Salute’s database, which collects Italian healthcare administrative data, all patients aged ≥ 35, with ≥1 primary in-hospital CAD diagnosis and/or procedure on the coronary arteries, or with the specific disease exemption code, and who are suitable for long-term secondary prevention treatments, were identified in 2018 and analyzed. Demographics, comorbidities, one-year supplied drugs, hospitalizations, and costs were analyzed. Results: From >3 million inhabitants aged ≥ 35, 46,063 (1.3%) were identified (72.1% males, mean age 70 ± 12; approximately 50% with ≥3 comorbidities). During a one-year follow-up, 96.4% were treated with ≥1 drug for secondary prevention (mainly antiplatelets and lipid lowering agents), 69.4% with ≥1 concomitant cardiovascular drug, and 95.8% with ≥1 concomitant non-cardiovascular therapy. Within one year, 30.6% of patients were hospitalized at least once, mostly due to non-cardiovascular events. Calculated by mean, the INHS paid EUR 6078 per patient. Conclusions: This analysis confirms the relevant burden of CAD for patients with many comorbidities and who are frequently hospitalized, and the burden on the INHS. A multidisciplinary healthcare approach is encouraged to improve patients’ outcomes and reduce costs for the INHS.

Prevalence, clinical impact and costs of hyperkalaemia: Special focus on heart failure

BACKGROUND

Hyperkalaemia is a potential life-threatening electrolyte abnormality. Although renin-angiotensin-aldosterone system inhibitors (RAASi) are potentially life-saving, they may contribute to hyperkalaemia.

METHODS

The prevalence, comorbidities, comedications and 1-year outcomes of patients admitted or treated for hyperkalaemia were investigated in a large healthcare administrative database including 12 533 230 general population inhabitants. A similar analysis was performed in the Italian Network on Heart Failure (IN-HF), a cardiology registry of 1726 acute and 7589 chronic HF patients, stratified by serum potassium. General practice healthcare costs related to hyperkalaemia were also assessed. Hyperkalaemia was defined by hospital coding, potassium-binder prescription or serum levels (mild: 5-5.4, moderate-severe: ≥5.5 mmol/L).

RESULTS

In the general population, the prevalence of hyperkalaemia was 0.035%. After excluding patients on haemodialysis, hyperkalaemia in the community (n = 2314) was significantly and directly associated with diabetes, chronic kidney disease, HF, RAASi prescriptions, 1-year hospitalisations and threefold annual healthcare costs, compared to age- and sex-matched non-hyperkalaemic subjects (n = 2314). In the IN-HF registry, hyperkalaemia affected 4.3% of acute and 3.6% of chronic patients and was significantly associated with diabetes, kidney disease and lesser use of RAASi, compared to normokalaemic patients. Among patients hospitalised for acute HF, those with hyperkalaemia at entry had significantly higher 1-year all-cause mortality compared with normokalaemic patients, even after adjustment for available confounders.

CONCLUSIONS

Hyperkalaemia in the general population, although uncommon, was associated with increased hospitalisations and tripling of healthcare costs. Among HF patients, hyperkalaemia was common and associated with underuse of RAASi; in acutely decompensated patients, it remained independently associated with 1-year all-cause mortality.