Prediction of Functional Outcomes at Discharge Using Plasma Concentration of von Willebrand Factor Antigen at Admission in Hospitalized Patients with COVID-19

Objectives: Coronavirus disease 2019 (COVID-19) causes endothelial injury through inflammatory and hypoxic stress, leading to vascular dysfunction and immunothrombosis. The plasma level of von Willebrand factor (VWF) could serve as a biomarker of vascular injury. While elevated VWF predicts mortality in severe COVID-19, its relationship with post-discharge functional outcomes remains unclear. This study aimed to determine whether plasma VWF antigen (VWF:Ag) levels at admission predict functional status at discharge in patients hospitalized for COVID-19. Methods: This was a single-center prospective cohort study conducted at Tokai University Hospital from July to September 2021. We evaluated the relationship between plasma VWF:Ag levels at admission and a Clinical Frailty Scale (CFS) score ≥4 at discharge using univariable and multivariable logistic regression analyses. Results: A total of 97 patients were enrolled in the study. The median VWF:Ag level at admission was 330.0% (95% confidence interval [CI]: 273.0-391.8). Univariable analysis showed a significant association between elevated VWF:Ag levels and CFS score ≥4 at discharge. This association remained significant after adjusting for age and sex (odds ratio 1.010, 95% CI: 1.000-1.010, p = 0.005). Conclusion: Elevated VWF:Ag levels at admission predict poor functional outcomes at discharge in COVID-19 patients, independent of age and sex.