Risk factors associated with 30-day mortality following COVID-19 infection in patients receiving kidney replacement therapy in Australian and New Zealand.

Background and aims: The COVID-19 pandemic impacted greatest among patients with pre-existing chronic health conditions, including chronic kidney disease. This retrospective cohort study aimed to investigate the 30-day mortality of patients receiving kidney replacement therapy (KRT) after infection with COVID-19, living in Australia and New Zealand between 2020 and 2022, including patients on haemodialysis (HD), peritoneal dialysis (PD) and renal transplant (KT) recipients.

Methods: This is a retrospective cohort study using data from the Australian and New Zealand Dialysis and Transplant Registry (ANZDATA). Patients were included if they tested positive for COVID-19 infection while receiving KRT between the first reported infection in January 2020 and the end of November 2022. Multivariable logistic regression was used to assess the relationship between KRT modality and 30-day mortality following COVID-19 infection, with all potential confounders included.

Results: A total of 9828 patients requiring KRT tested positive for COVID-19 within Australia and New Zealand between 2020 and 2022. The crude mortality rate by KRT modality was 3.0% for HD, 3.8% for PD and 2.4% for KT. In the adjusted model, there was a significant increase in the odds of mortality for increasing age, diabetes, peripheral vascular disease, having ever smoked and having received dialysis for ≥5 years. Relative to HD, KT recipients had increased odds of death in 2021 and 2022 but not 2020.

Conclusions: The 30-day mortality rate following COVID-19 infection in patients requiring KRT was significantly higher than the general population, with several risk factors identified associated with increased mortality rates.