Possible link between blood clots and Covid symptoms investigated

Researchers in the UK are looking into a link between blood clot and Covid symptoms.

Covid can cause a short-term illness, but it can also lead to long-term problems. Less than a third of patients who have been hospitalized with Covid symptoms feel like they're recovered a year later, according to research.

Researchers are going to conduct a number of trials to see if blood thinners can help people who have had the disease.

People who have had a Covid infection are more likely to have strokes, heart attacks and deep vein thrombosis.

More than a third of long Covid patients have clotting abnormality, according to studies in the UK, while research in South Africa suggests that people with long Covid have small blood vessels.

He said it was not clear if the findings were generalisable, and that more research was needed as blood thinners can lead to an increased risk of bleeding.

The point was echoed by Prof Betty Raman, of the University of Oxford, who cautioned that studies into microclots and long Covid had not yet been carried out on a large scale.

The efficacy of long Covid needs to be looked at in the same way as how we treated acute unwell patients.

The Stimulate-ICP trial, which is due to start recruiting within days, will split 4,500 people with long Covid into four groups in which participants are allocated usual care, antihistamines, an anti- inflammatory or an anti-clotting drug. The ability to say whether that improves the fatigue and other outcomes of people with long Covid will be given by that.

While the trial focuses on people who had Covid in the community, another study, called Heal- Covid, involves people who were hospitalized with the disease, hoping to identify treatments that may help to prevent or reduce ongoing symptoms.

"Heal- Covid is not a study treating people with long Covid, we are aiming to prevent things from getting to that point," said Prof Charlotte Summers of the University of Cambridge, who is chief investigator on the work.

One arm of the trial involves participants receiving blood thinners. There was thought to be an increased number of large blood clot occurring in the post-hospital phase of the illness.

The issue of clotting is being probed by the post-hospitalization Covid-19 study.

Chris Brightling, a professor of respiratory medicine at the University ofLeicester and chief investigator on the study, said one area they were looking at was whether people with ongoing symptoms after being in hospital have chronic thromboembolic pulmonary hypertension. It would be strong evidence that microclots are a serious problem if this was found.

It is less likely that it is a major problem if we don't see that.

Some patients with Covid may be frustrated that certain therapies are not yet available, but rigorous studies are necessary. He said that they needed to make sure that they didn't lower the bar for safety.