Potassium is essential for the body to function correctly and is especially important for the proper functioning of nerves and muscles, including the heart. The medical term hyperkalaemia is used when the level of potassium in the blood is higher than the upper limit of the normal range. Patients with hyperkalaemia are at increased risk of problems with the heart, including heart attack, death and hospitalisation.
The kidneys control the level of potassium in the body, so hyperkalaemia is most common in people who take medicines that may affect the kidneys, or people who have medical conditions associated with poor kidney function such as diabetes, heart failure (HF) and chronic kidney disease (CKD). Understanding the distribution of hyperkalaemia (which patients, how often, and how severe) and predicting patient outcomes, such as death, may lead to better patient management.
With this in mind, this study aims to use an anonymised primary care database and linked secondary care data to: (i) describe the characteristics of patients that experience hyperkalaemia and patterns of hyperkalaemia episodes; and (ii) asses how well existing statistical models can predict the risk of hyperkalaemia and patient outcomes such as death.
Hyperkalaemia is an electrolyte imbalance typically defined as a serum potassium concentration ?5.0 mmol/L, associated with adverse clinical outcomes including major adverse cardiovascular events (MACE), hospitalisation and associated length of stay, and all-cause mortality.
CKD, HF, resistant hypertension and diabetes are significant risk factors for the development of hyperkalaemia, and patients with these comorbidities are at increased risk of experiencing elevated serum potassium. Renin-angiotensin-aldosterone system inhibitors (RAASi) are prescribed to manage such comorbidities but further increase the risk of hyperkalaemia.
Recently published real-world studies have largely examined associations between hyperkalaemia and adverse clinical outcomes in relatively narrowly-defined patient populations. Furthermore, there is a relative paucity of studies that elucidate risk factors for hyperkalaemia itself and, where such studies do exist, it is currently unclear whether their results generalise to alternative patient populations and healthcare systems.
This real-world study aims to explore the patterns of hyperkalaemia, including its chronicity and burden, in a broad population of patients with cardiorenal comorbidities and at elevated risk of hyperkalaemia. The study also aims to assess the generalisability of existing risk equations for predicting the incidence of adverse clinical outcomes as a function of serum potassium in patients with established cardiorenal comorbidities.
Incident hyperkalaemia
Recurrent hyperkalaemia
All-cause mortality
Major adverse cardiovascular event
Discontinuation of renin-angiotensin-aldosterone system inhibitors
Glen James - Chief Investigator - AstraZeneca Ltd - UK Headquarters
Phil McEwan - Corresponding Applicant - Health Economics & Outcomes Research Ltd ( HEOR Ltd )
Carl Mellström - Collaborator - AstraZeneca Ltd - UK Headquarters
Carmen Tsang - Collaborator - Health Economics & Outcomes Research Ltd ( HEOR Ltd )
Jennifer Kim - Collaborator - AstraZeneca Ltd - UK Headquarters
Kerrie Ford - Collaborator - Health Economics & Outcomes Research Ltd ( HEOR Ltd )
Marc Evans - Collaborator - Llandough Hospital
Nia Jenkins - Collaborator - Health Economics & Outcomes Research Ltd ( HEOR Ltd )
John Clegg - Chief Investigator - AstraZeneca Ltd - UK Headquarters
Qin Lei - Chief Investigator - Astra Zeneca Inc - USA
Michael Hurst - Collaborator - Health Economics & Outcomes Research Ltd ( HEOR Ltd )
HES Accident and Emergency;HES Admitted Patient Care;ONS Death Registration Data;Patient Level Index of Multiple Deprivation