Factors related to COVID-19 mortality among three Swedish intensive care units—A retrospective study

Abstract

Background: Mortality due to acute hypoxemic respiratory failure (AHRF) in patients with coronavirus disease-19 (COVID-19) differs across units, regions, and countries. These variations may be attributed to several factors, including comorbidities, acute physiological derangement, disease severity, treatment, ethnicity, healthcare system strain, and socioeconomic status. This study aimed to explore the features of patient characteristics, clinical management, and staffing that may be related to mortality among three intensive care units (ICUs) within the same hospital system in South Sweden. Methods: We retrospectively analyzed ICU patients with COVID-19 and AHRF in Region Jönköping County, Sweden. The primary outcome was the 90-day mortality rate. We used univariate and multivariable logistic regression analyses to investigate the relationship of predictors with outcomes. Results: Between March 15, 2020, and May 31, 2021, 331 patients with AHRF and COVID-19 were admitted to the three ICUs. There were differences in disease severity, treatments, process-related factors, and socioeconomic factors between the units. These factors were related to 90-day mortality. After multivariable adjustment, age, severity of acute respiratory distress syndrome, and the number of nurses per ICU-bed independently predicted 90-day mortality. Conclusion: Age, disease severity, and nurse staffing, but not treatment or socioeconomic status, were independently associated with 90-day mortality among critically ill patients with AHRF due to COVID-19. We also identified variations in care related processes, which may be a modifiable risk factor and warrants future investigation.