Outcomes of hospitalised patients with hyperkalaemia at a South African tertiary healthcare centre

Mogamat-Yazied Chothia; Usuf Chikte; Anneliese Zemlin; Desiree Moodley; Nicolas Fitchat; Anneliese Wessels; Esther van Vuuren; Thaabit Davids; Mogamat Razeen Davids

doi:10.1016/j.eclinm.2022.101536

Outcomes of hospitalised patients with hyperkalaemia at a South African tertiary healthcare centre

EClinicalMedicine. 2022 Jul 1:50:101536. doi: 10.1016/j.eclinm.2022.101536. eCollection 2022 Aug.

Authors

Mogamat-Yazied Chothia¹, Usuf Chikte², Anneliese Zemlin³, Desiree Moodley¹, Nicolas Fitchat¹, Anneliese Wessels¹, Esther van Vuuren¹, Thaabit Davids¹, Mogamat Razeen Davids¹

Affiliations

¹ Division of Nephrology, Department of Medicine, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa.
² Division of Health Systems and Public Health, Department of Global Health, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa.
³ Division of Chemical Pathology, Department of Pathology, Faculty of Medicine and Health Sciences, Stellenbosch University and National Health Laboratory Service, Tygerberg Hospital, Cape Town, South Africa.

Abstract

Background: Hyperkalaemia is a common electrolyte disorder in hospitalised patients. There is a lack of data from Africa on the prevalence, causes and outcomes of patients with hyperkalaemia. We aimed to identify the frequency of hyperkalaemia in hospitalised adults, and to identify any risk factors for in-hospital death.

Methods: We conducted a retrospective cohort study of 1921 adult patients admitted to hospital with hyperkalaemia (potassium concentration ([K]) ≥ 5·5 mmol/L) over a one-year period during 2019. Multivariable logistic regression was performed to identify predictors of in-hospital mortality and multilinear regression was used to identify associations with the [K].

Findings: We found an incidence rate of 3·7 cases per 100 patient-years. Nearly a third died during hospitalisation. Acute kidney injury (AKI) was common in patients who died (69·2% vs. 41·3%, P < 0·01). Age (odds ratio (OR) 1·02, 95% CI 1·01-1·03), [K] (OR 1·38, 95% CI 1·12-1·71), AKI (OR 3·13, 95% CI 2·19-4·47) and acute therapy (OR 1·93, 95% CI 1·40-2·66) were predictors of in-hospital death. AKI (r = 0·29, P < 0·01) and chronic kidney disease (r = 0·31, P < 0·01) were associated with the [K]. Fourteen percent of patients with hyperkalaemia were HIV positive with no difference in in-hospital death (P = 0·75).

Interpretation: This is the largest study reporting on the epidemiology of hyperkalaemia in hospitalised adults from Africa. Hyperkalaemia in association with AKI was a strong predictor of in-hospital death. Late presentation to hospital may be a major factor contributing to poor outcomes.

Funding: Self-funded.

Keywords: Africa; HIV; Incidence; Mortality; Potassium; Prevalence.