It is one of the main conclusions of a review of studies led in Canada by the Argentine neurologist Luciano Sposato, whose results are published in Neurology.
No fever, no cough, sore throat, shortness of breath, headache or muscle pain. Neither diarrhea or vomiting, nor sudden loss of smell and / or taste. In some people, especially young people, the first symptom of Covid-19 is a cerebrovascular attack (CVA or stroke). This is one of the main conclusions of a study carried out in Canada, led by the Argentine neurologist Luciano Sposato.
“Any patient who comes to the guard at this time with a stroke, you have to think that you may have covid. Why? Because Covid-19 today is a cause of stroke. When is it more suspicious? When they are young patients, without a history of comorbidities or risk factors, they live in areas with community circulation of the virus, and when large clots are seen in the arteries, “said Sposato in a telephone dialogue with Clarion from Ontario.
It is known that infection by the new SARS-CoV-2 coronavirus can cause manifestations beyond the lungs and compromise the activity of different organs and tissues, which is why there is talk of its multisystemic impact, which in some cases is related to its high risk of producing venous and arterial thrombotic events, including stroke.
In order to know the frequency, clinical characteristics and results of cerebrovascular attacks associated with Covid-19, a team of researchers from the University of Western Ontario conducted a systematic review of studies published in scientific journals until May 29 and They also added unpublished cases from Canada, Iran and the United States. The analysis included 160 patients (57% men and 43% women), of which 29 were under 50 years of age. The median age was 65 years.
One of the main results of the article published in the journal Neurology, of the American Academy of Neurology, is that around 2 out of 100 people hospitalized with Covid-19 suffer a stroke before or during hospitalization. This 1.8% incidence is relatively high compared to the percentage registered in patients hospitalized for other viral respiratory infections: it represents twice that for SARS-CoV-1 (0.75%) and is eight times more frequent than reported for flu (0,2%).
The authors caution that despite the high, this figure may even be an underestimate, given that many patients die without a confirmed diagnosis and that some do not go to the emergency department when they experience mild symptoms.
Stroke associated with covid has a high mortality, among 35% and 45%, the researchers found. These rates are above those reported for severe strokes – which require admission to intensive care – not linked to the disease caused by the new coronavirus, which range between 15% and 30%.
Advanced age, the presence of one or more comorbidities (previous diseases) and severe respiratory symptoms (requiring intensive care and / or mechanical ventilation) are associated with higher mortality, according to the estimate made by an unsupervised machine learning system used to identify the factors that increase the risk of dying from covid-related stroke.
However, for Sposato, the most notable finding is that linked to stroke by Covid-19 in people under 50 years of age. For the neurologist who directed teams here at INECO and the Favaloro Foundation and who has worked for years at the London Health Sciences Center in Canada, the risk young people face is often underestimated in the face of the new coronavirus.
“Stroke is a clinical form with which these patients can debut. It was the first symptom covid in 50% of the young patients in the study. That is, for me, the most surprising fact of all. Furthermore, 45% had absolutely no no comorbidity no risk factors. It is as if it were an explosive cocktail, “says Sposato, who nevertheless points out that due to the small size of the sample (the bibliography on the matter is still limited), which corresponds to cases reported in isolation, these are data that cannot be extrapolated to different populations. “But we can affirm that it affects young people,” he stresses.
This finding, according to the researchers, may imply that, during the pandemic, younger patients requiring care for an acute stroke should be tested for SARS-CoV-2, even in the absence of specific symptoms.
The study also found a higher proportion of patients with ischemic stroke in whom the sudden loss of cerebral blood flow is due to the presence of large clots in the arteries. “We see that in 29% of ischemic stroke cases and here we saw it in around 49% of the entire population. And if we take only young people, we saw it in 68% (although this last data is not statistically significant due to the small number of the sample) “, Sposato says.
Although the study could not quantify the severity of the neurological damage because in most of the cases studied that data had not been reported, the specialist points out that a clot that obstructs the great arteries is generally associated with a severity of stroke three times greater than a common stroke, because it covers a large artery on which a large proportion of brain tissue depends.
Two factors would explain the clot formation linked to Covid-19. One is the exaggerated immune system response that is awakened in some patients by the presence of the virus, in which an inflammatory cascade occurs that activates the coagulation system.
“On the other hand, there is something called endothelial dysfunction – explains Sposato -. The endothelium are the cells that line the vessels from inside, which are very involved in the homeostasis of coagulation. Their function is affected by inflammation and by other factors, that we do not know if it is the virus directly. And that favors that this balance, which is so stable in normal situations, lean toward hypercoagulability in many cases.”
Acute treatment is the same as for a stroke due to other causes and includes the use of rTpa (a fibrinolytic to dissolve the clot) and mechanical thrombectomy to remove thrombi from the great vessels with a catheter. Both procedures can be done within a time window, so it is important that people with strokes receive urgent care.