Woman with facemask

Blood clotting could be root cause of long COVID syndrome

  • Research

A study led by researchers from RCSI University of Medicine and Health Sciences, has found a link between blood clotting and long COVID syndrome.

Long COVID syndrome is the name given to a condition that occurs in patients whose symptoms can last weeks to months after the initial COVID-19 infection. The syndrome is estimated to affect millions of people worldwide with common persistent symptoms experienced such as fatigue and reduced physical fitness.

In the study, 50 patients with symptoms of long COVID were analysed. It was found that patients with the syndrome had significantly elevated clotting indicators in the blood compared to healthy patients.

It was also found that these markers remained elevated even when inflammation caused by the initial infection had returned to normal, indicating that the clotting mechanism may be responsible for long COVID. 

In addition, it was found that clotting markers were more common in patients who required hospitalisation with their initial COVID-19 infection than those who did not. However, those who managed their initial infection without requiring hospitalisation also had persistently high clotting markers. Blood clotting markers were also found to be directly related to other symptoms of long COVID such as fatigue and reduced physical fitness.

The findings of the study are important for researchers and clinicians as they seek to learn more about COVID-19 and how to treat it.

Published in the Journal of Thrombosis and Haemostasis, the study was led by Dr Helen Fogarty, ICAT Fellow and PhD student at the Irish Centre for Vascular Biology in RCSI School of Pharmacy and Biomolecular Sciences.

The work was funded by the Wellcome Trust, the Health Research Board (HRB) Irish Clinical Academic Training (ICAT) programme as well as the HRB-funded Irish COVID-19 Vasculopathy Study (ICVS). The study was supported by a philanthropic grant in support of COVID-19 research from the 3M Foundation.

RCSI is committed to achieving a better and more sustainable future through the UN Sustainable Development Goals.