New research on patients with severe COVID-19 has found that elevated levels of a marker in the blood, von Willebrand factor propeptide, is linked to more severe disease and poorer outcomes for hospitalised patients with COVID-19.

The findings may help clinicians to stratify patients at high risk of developing severe thrombotic and respiratory complications. The study, led by researchers from the RCSI University of Medicine and Health Sciences, is published in the current edition of the British Journal of Haematology.

The research helps doctors to understand why patients with COVID-19 develop the blood clotting abnormalities that can trigger micro-clot development in the lungs. Previous research has found that the development of these micro-clots can lead to a poorer prognosis for patients and increased risk of intensive care admission.

This study links the formation of these micro-clots to elevated blood levels of the marker, von Willebrand factor propeptide, an established blood marker for damage to the endothelial cells lining the blood vessels in the body. Acute damage of these cells results in the rapid release of von Willebrand factor propeptide but also initiates clot formation and inflammation. The study observed the highest levels of the blood marker in patients with most severe COVID-19 disease or those who succumbed to COVID-19, indicating that levels of the marker may be predictive for poor prognosis and outcome in patients with COVID-19.

Professor James O’Donnell, Director of the Irish Centre for Vascular Biology, RCSI and Consultant Haematologist in the National Coagulation Centre in St James’s Hospital, said: “We have previously established that abnormal blood clotting and the development of micro-clots within the lungs contributes to a greater risk of a poorer prognosis and intensive care admission for Irish patients with COVID-19. The mechanisms through which COVID-19 triggers the formation of these micro-clots however has been puzzling doctors throughout the world. This research now critically helps us to more clearly understand these mechanisms.”

Dr Jamie O’Sullivan, StAR Research Lecturer at the Irish Centre for Vascular Biology at RCSI and co-senior author on the paper, said: “This study provides further insight into the marked and sustained damage to the cells lining the blood vessels in patients with severe COVID-19 and how this may contribute to thrombotic complications’’

The study was carried out by researchers from the Irish Centre for Vascular Biology, School of Pharmacy and Biomolecular Sciences, RCSI; Department of Anaesthesia and Critical Care, RCSI; Department of Infectious Diseases, Beaumont Hospital, Dublin; National Coagulation Centre, St James’ Hospital, Dublin; St James’ Hospital, Trinity College Dublin; St Vincent’s University Hospital, Dublin; and the National Children’s Research Centre, Our Lady’s Children’s Hospital, Crumlin, Dublin.

The research was funded through the Irish COVID-19 Vasculopathy Study (ICVS) via the Health Research Board COVID-19 Rapid Response Awards (COV19-202-086) and a philanthropic grant from 3M to RCSI in support of COVID-19 research.