A new study has revealed that people suffering from long Covid are at an increased risk of abnormal blood clotting.
The study was conducted by University College London Hospitals NHS Foundation Trust (UCLH) in conjunction with University College London and offers new insight into the potential mechanisms behind the long-term effects of Covid.
Given long Covid’s status as an emerging condition, much of its biological base is still yet unknown, with this research providing new insight.
“By definition, this syndrome occurs when one experiences Covid-related symptoms long after the onset of infection that we can't attribute to any other cause or diagnosis,” explained study author Dr Nithya Prasannan, of the Department of Haematology at UCLH. “This study offers us laboratory and clinical evidence to begin to understand why some people experience long Covid symptoms.”
A team led by UCLH’s Dr Melissa Heightman assessed people in an outpatient post-Covid clinic between July 2020 and May 2021.
Researchers measured abnormal blood clotting markers by assessing the relative levels of two proteins in the body. The researchers then analysed the ratio of Von Willebrand factor (VWF), which is important in blood clotting, to ADAMTS13, a protein that cuts VWF to prevent it from clogging blood vessels.
If the ratio of VWF significantly outweighed ADAMTS13 in the bloodstream, scientists characterised patients as being in a pro-thrombotic state, meaning they could face a greater risk of developing blood clots.
Patients also completed exercise tests, such as repeatedly going from a standing position to a sitting position while wearing oxygen monitors.
Researchers measured the patient’s oxygen levels before and after exercise to measure their lactate levels. Patients who showed a significant decrease in oxygen levels while exercising or a rise in lactate afterwards were said to demonstrate an impaired exercise capacity.
Patients with raised levels of blood clotting markers were also four times more likely to have an impaired exercise capacity.
More information on the study can be found here.
