Even if coronavirus is a respiratory infectious agent, affected patients also have specific and nonspecific neurological symptoms, such as anosmia, dizziness, and headache.
With the spread of the pandemic, reports of serious neurological and neuropsychiatric presentations associated with COVID-19 have become more frequent.
In China, the SARS-CoV-2 virus has also been isolated in the cerebrospinal fluid of a patient with encephalitis.
In the past weeks, a new study has analyzed the incidence of another possible complication of COVID-19: stroke. The research, published in the journal JAMA Neurology, assessed the incidence of ischemic stroke in COVID-19 patients.
A control group composed by subjects affected by influenza was also considered in the analysis. Influenza is a viral respiratory disease that previous studies have associated with an increase in the incidence of stroke.
This retrospective study was conducted in two New York academic hospitals and included patients with emergency room visits or hospitalizations for confirmed COVID-19.
The control group included patients with emergency room visits or hospitalizations for type A / B flu virus in the period from January 1, 2016 until May 31, 2018.
There were 1,916 cases of COVID-19 recorded in the two hospitals during the study period. Their mean age was 64 years and 57% of them were male.
Among them, ischemic stroke occurred with an incidence of 1.6%, a percentage that rises to 1.8% considering only hospitalized patients. The time interval between symptoms onset and stroke diagnosis was 16 days. The mean age of patients with stroke was 69 years and 58% were male.
Thirty five percent of ischemic strokes occurred in patients with severe COVID-19 infection, undergoing mechanical ventilation. Hospital mortality among patients with COVID-19 was 32% among those who had developed an ischemic stroke and 14% in others.
Among the 1,486 flu patients identified in the study, the incidence of ischemic stroke was 0.2%.
Even after adjusting for age, gender and race, the likelihood of stroke was higher in patients with COVID-19 than in those with flu.
The study authors make some considerations to explain the higher incidence of ischemic stroke among patients with COVID-19.
The first is based on the fact that viral infections generally act as triggers that increase the risk of ischemic stroke and other arterial thrombotic events.
The mechanisms involved are related to the development of inflammation and the generation of prothrombotic phenomena. In patients with COVID-19, particularly violent inflammatory response has been highlighted, also associated with an increase in D-dimer levels and the presence of antiphospholipid antibodies.
The second, considers patients with COVID-19 to be at greater risk of ischemic stroke due to the more frequent presence in these subjects of complications such as atrial arrhythmias, heart failure and venous thrombosis, which can contribute to favoring the development of a stroke.
Although our understanding of neurological complications in COVID-19 patients is still poor, a clear relationship between these events seems to emerge.
The authors conclude by stressing that their results should encourage physicians to be vigilant to promptly detect symptoms and signs of ischemic stroke in patients with COVID-19, to respond quickly with appropriate therapeutic measures.
This post is also available in: Chinese (Simplified)