A study by Vall d’Hebron shows that patients with severe pulmonary injury due to COVID-19 have increased risk of stroke

The results of a study carried out by Vall d’Hebron show that people with COVID-19 and severe pulmonary injury have a higher risk of presenting a stroke. However, this does not happen in COVID-19 patients without severe pulmonary injury, who have the same risk of stroke as the rest of the population. The work, carried out between March and April, has been published in the Journal of Stroke and Cerebrovascular Diseases.

Throughout these months of pandemic, it has been proved that SARS-CoV-2 infection is associated, in many patients, with the appearance of thrombosis, especially pulmonary thromboembolism that can lead to serious complications and even death. In order to understand the risk posed by COVID-19 for the onset of ischemic stroke, which is caused by thrombi in the brain, professionals from the Stroke Unit at Vall d’Hebron followed up 2,050 patients admitted to the hospital during the two months that the study lasted.

Among the total of patients included in the study, 21 suffered an ischemic stroke. They included people who were asymptomatic for COVID-19, people with symptoms of COVID-19 before the stroke and people who developed symptoms of COVID-19 after the stroke, during their stay in the hospital. However, researchers did not find a relationship between COVID-19 and stroke in all cases, since 12 of them had some of the most common risk factors for stroke in general population, such as smoking, high levels of cholesterol, high blood pressure, etc. Six of the patients did not have any of the risk factors commonly associated with stroke. The rest of the patients died before the origin of the stroke could be established.

“In these six patients, without risk factors and whose stroke we related to COVID-19, had severe pulmonary injury that required mechanical ventilation. Therefore, the study shows that, in patients with COVID-19, the risk of presenting a stroke only increases if they have severe pulmonary injury”, explains Dr. Manuel Requena, from the Stroke Unit of Vall d’Hebron University Hospital and researcher of the Stroke Research group at Vall d’Hebron Institut of Research (VHIR) and first author of the study. This finding agrees with the results of previous studies that relate this type of damage to the lungs, as well as infection by some bacteria and viruses, with the appearance of neurological symptoms and in particular with stroke. In this way, SARS-CoV-2 virus would follow the same behavior as other viruses. Dr. Requena emphasizes that “most patients with COVID-19 do not have severe pulmonary injury. And in these cases we have verified that the risk of stroke does not increase”.

On the other hand, this study shows that patients with COVID-19 who present a stroke caused by the obstruction of large blood vessels and are treated by thrombectomy, the standard treatment, have a worse prognosis and higher mortality that those who do not have the infection. “The worse clinical evolution of these patients could be due to the lung damage associated with COVID-19, which would cause less oxygen to reach the brain and, therefore, the stroke treatment wouldn’t be so affective”, says Dr. Requena.