Emergency medical system utilization among patients with end-stage kidney disease during the COVID-19 pandemic: a retrospective cohort study in South Korea

Introduction: Patients with end-stage kidney disease (ESKD) are particularly vulnerable to adverse outcomes from coronavirus disease 2019 (COVID-19). We aimed to compare emergency department (ED) utilization patterns and clinical outcomes among patients with ESKD before and during the COVID-19 pandemic to inform future healthcare planning. Methods: We analyzed data from the National Emergency Department Information System (NEDIS), a nationwide database of ED visits in South Korea. Adult patients with ESKD who visited the ED between January 1, 2018, and May 31, 2021, were included. ED visits were categorized into pre- COVID-19 (2018-2019) and COVID-19 (2020-2021) periods based on visit date. Trends in ED visit frequency, presenting causes, clinical severity, hospitalization, and short-term mortality were compared using descriptive statistics and multi-variate logistic regression. Results: A total of 159,456 ED visits were analyzed (76,277 in 2018-2019; 83,179 in 2020-2021). Compared with the pre-pandemic period, ED visits during the COVID-19 period increased and were associated with higher odds of hospitalization [adjusted odds ratio (aOR), 1.054; 95% confidence interval (CI), 1.031-1.079] and mortality (aOR, 1.052; 95% CI, 1.007-1.099). This trend was most notable among patients presenting with severe conditions. Vascular access complications were the leading cause of ED visits during the COVID-19 period. Patients with severe illness were more likely to visit high-level hospitals and had higher rates of hospitalization and in-hospital mortality during the pandemic. Conclusion: The study found that patients with ESKD experienced an increase in ED visits during the COVID-19 pandemic, along with a higher risk of hospitalization and mortality; however, the distribution of patients across hospital service levels improved during the outbreak. These findings can inform preparedness strategies for future public health emergencies.