Coronavirus may cause an increased risk of blood clots and blockages in the brain and could lead to a stroke, according to a new study from University College London.
The small study focused on six patients with confirmed COVID-19 who had suffered a stroke caused by the sudden loss of blood flow to the brain.
The team, which included neurologists from the National Hospital for Neurology and Neurosurgery, found an increase in D-dimer – a blood protein linked to clotting.
The authors say that the exaggerated inflammatory immune response known in COVID-19 patients stimulates abnormal blood clotting in the brain.
The coronavirus can cause an increase in the number of blood clots in the brain and lead to a stroke in some patients, according to a new study from University College London. Stock Image
The article, published in the Journal of Neurology, Neurosurgery, and Psychiatry, could not confirm a direct link between the coronavirus and stroke because it was a small study.
“It is also possible that the effects of social distancing and anxiety about the hospital visit may have influenced the spectrum of ischemic stroke mechanisms in patients seen in our hospital,” wrote the authors. .
However, they say there was evidence of an increase in D-dimer in the blood – that is, production of antibodies created from an abnormal immune system response.
Corresponding author, Professor David Werring and his colleagues examined six patients who had an acute ischemic stroke due to the blockage of a large cerebral artery.
Acute ischemic stroke is caused by the sudden loss of blood flow to an area of the brain, resulting in loss of neurological function.
The results suggest that early detection of D-dimer in COVID-19 patients could allow clinicians to prescribe specific treatments at a much earlier stage.
They say it could reduce the number of people who later have other strokes or blood clots elsewhere in the body.
Professor Robert Storey, Professor of Cardiology, Department of Infections, Immunity and Cardiovascular Disease, University of Sheffield, said that it is not surprising to find a link between COVID-19 and stroke the infection can cause inflammation in the body.
He said the inflammation is linked to an increased risk of blood clots in the blood vessels, which is the most common cause of heart attack and stroke.
“Inflammation can also accelerate the buildup of fatty deposits in the blood vessels supplying the heart and brain, which can eventually lead to blood clots and blockage of blood vessels.”
The six patients (aged 53 to 85) had a large arterial blockage, with markedly high D-Dimer blood levels and confirmed COVID-19.
Researchers say this indicates the presence of abnormally high “fibrin breakdown products” – components in the blood produced when clots break down.
Five of the six ischemic strokes occurred 8 to 24 days after the onset of COVID-19 symptoms and in one patient during the presymptomatic phase.
Researchers say this suggests that the stroke associated with COVID-19 is usually delayed, but can occur both early and later in the course of the disease.
Professor Tim Chico, professor of cardiovascular medicine and honorary consultant cardiologist, University of Sheffield, said the results of this study were consistent with other evidence linking COVID-19 to the risk of blood clots.
“Because people otherwise healthy or sick with diseases other than COVID-19 often suffer from blood clots, it is impossible to say in an individual that their blood clot was ’caused’ by COVID-19 ” , did he declare.
“However, the increasing number of publications and the experience of physicians treating COVID-19 patients, including myself and my colleagues, strongly suggest that COVID-19 significantly increases the risk of blood clots in hospital patients.
The article, published in the Journal of Neurology, Neurosurgery, and Psychiatry, did not confirm a direct link between the coronavirus and stroke, as it was a small study. . Stock Image
Discussing the results, Professor Werring said that we already know that COVID-19 is not just a disease of the lungs – it proves a link with stroke in some patients.
“Our results suggest that blockages of the large cerebral arteries in COVID-19 patients are associated with very abnormal blood clotting,” he said.
“Early use of blood thinners may be helpful, but it must be weighed against their risk of brain bleeding, especially soon after a stroke.”
He said clinical studies are needed to find the best treatment to reduce the disability caused by ischemic stroke in people with COVID-19.
“Our results underscore that even during the lockdown, people with suspected stroke need to go to the hospital right away to make sure they get the best treatment.”
In addition to clinical trials on vaccines and studies on antiviral drugs, a number of clinical trials are examining the level of anticoagulant therapy to be used in people hospitalized with COVID-19.
“This study cannot tell us what proportion of COVID-19 patients have blood clots, or whether the risk of this is related to the severity of the disease or may occur even in people with mild or no symptoms” said Professor Chico.
This requires an in-depth study including thousands of patients, he said.
There has been a “disturbing reduction in admissions for stroke and heart attacks unrelated to COVID-19,” said Chico, adding that this could hide a bigger problem.
“People who are already taking blood thinners such as aspirin should continue to take them if they develop symptoms similar to COVID-19, unless advised by their medical team,” said Chico.
The research “Characteristics of ischemic stroke associated with COVID-19” was published in the Journal of Neurology, Neurosurgery, and Psychiatry.