IMpact of hyPeRkalaemia on thErapy With Renin angiotenSin aldoSterone System Inhibitors

Study Overview
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Brief Summary
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There are limited data regarding the burden of hyperkalaemia in patients attending emergency departments (ED) or who are hospitalised (excluding those already receiving dialysis). Renin-angiotensin-aldosterone system inhibitors (RAASi) are of prognostic benefit in patients with heart failure with reduced ejection fraction (HFrEF) and post myocardial infarction (MI) left ventricular systolic dysfunction (LVSD) and as such should be continued wherever possible for these indications. These drugs may contribute to elevation in serum potassium and hyperkalaemia may lead to a reduction in dose or complete withdrawal of RAASi. Yet it remains unknown how common this happens in standard clinical practice. Inappropriate discontinuation of RAASi in such patients may lead to adverse clinical outcomes. If patients have hyperkalaemia that limits the use of RAASi, they may be candidates for new potassium binders that could facilitate their continued use.

Detailed Description
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Research questions: In an adult population of patients who are hospitalised or attending the emergency department (and not receiving dialysis) with hyperkalaemia: How does hyperkalaemia impact on RAASi therapy and does this vary according to the clinical indication for the drug(s)? What are the demographics, co-morbidities and drug history for patients presenting with hyperkalaemia? What is the frequency of subsequent hospitalisations and mortality rate in a cohort of patients presenting with hyperkalaemia at 12 months?

Official Title
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IMpact of hyPeRkalaemia on thErapy With Renin angiotenSin aldoSterone System Inhibitors

Conditions
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Hyperkalemia

Intervention / Treatment
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* Other: No intervention


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients in ED or inpatients with at least 1 blood test with a potassium level of ≥5.5 mmol/l Receiving RAASi. Aged 18 and above. Able to provide informed consent or consent provided by consultee in those unable to consent for themselves. Exclusion Criteria: Patients already receiving dialysis prior to the episode of hyperkalaemia. For patients considered for postal consent: known cognitive impairment, learning difficulties or brain injury or those who had transient cognitive impairment, delirium or required urgent deprivation of liberty form completion during inpatient stay or in the previous 12 months prior to hyperkalaemia episode.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Intervention/Treatment |
| --- |
|Other: No intervention|No intervention|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Proportion of patients who take RAASi for clear prognostic indications and who had changes to RAASi as a result of hyperkalaemia. | Proportion of hospitalised patients/ED attenders receiving RAASi for clear prognostic indication who experience RAASi dose reduction/withdrawal due to hyperkalaemia at discharge. | 12 months | 
| Proportion of patients who take RAASi without clear prognostic indications and who had changes to RAASi as a result of hyperkalaemia. | Proportion of hospitalised patients/ED attenders receiving RAASi without clear prognostic indication who experience RAASi dose reduction/withdrawal due to hyperkalaemia at discharge. | 12 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Recurrent hyperkalaemias. | Number of repeated episodes of hyperkalaemia after initial episode according to laboratory reports (episodes can be as inpatient or outpatient) captured during study period. | 12 months | 
| Proportion of patients continuing of RAASi. | Proportion of patients continuing of RAASi therapy after initial episodes of hyperkalaemia at 3 months and 12 months. | 3 months and 12 months | 
| Hospitalisations | Number and causes (all cause, cardiovascular or HF) of hospitalisations at 12 months | 12 months | 
| Mortality | Number and causes (all cause, cardiovascular or HF) of mortality at 12 months. | 12 months | 
| Level of hyperkalaemia leading to changes to RAASi. | Level of hyperkalaemia at which healthcare professionals reduce dose/stop RAASi. | 12 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Hyperkalemia due to RAASi, RAASi, Hyperkalaemia