By Matthew E. Fink, MD

Louis and Gertrude Feil Professor and Chair, Department of Neurology, Associate Dean for Clinical Affairs, New York Presbyterian/Weill Cornell Medical College

Dr. Fink reports no financial relationships relevant to this field of study.

SOURCE: Merkler AE, Parikh NS, Mir S, et al. Risk of ischemic stroke in patients with coronavirus disease 2019 (COVID–19) vs patients with influenza. JAMA Neurol 2020; July 2. doi:10.1001/jamaneurol.2020.2730. [Online ahead of print].

Early in the COVID-19 pandemic, reports emerged from China and France that there might be an increased risk of ischemic stroke. It was noted that many patients developed a hypercoagulable state with thrombotic complications in multiple organs, including the lungs, kidneys, heart, liver, and brain. During the recent surge in coronavirus infection cases in New York City, many neurologists observed an unusual frequency of ischemic stroke.

The investigators at Weill Cornell Medicine designed a retrospective cohort study of patients admitted with COVID-19 infection, confirmed by polymerase chain reaction testing by a nasal swab, from March 4, 2020, through May 2, 2020. They identified all acute strokes, and compared them with a matched group of patients hospitalized with influenza A and B from January 2016 through May 2018. It is well documented that influenza epidemics are associated with an increased risk of ischemic stroke and myocardial infarction, as are all systemic inflammatory disorders. These investigators wanted to determine if coronavirus infection induced a higher risk of ischemic stroke than other viral infections, such as influenza.

One thousand nine hundred sixteen patients with documented COVID-19 infection were admitted to the hospital, and 31 had an acute ischemic stroke during their hospitalization (1.6%; 95% confidence interval [CI], 1.1%-2.3%). The median age was 69 years, and 58% were men. Eight patients presented to the hospital with stroke as their chief complaint. Of 1,486 patients with influenza, only three had an acute ischemic stroke during hospitalization (0.2%; 95% CI, 0.0%-0.6%). After adjustment for demographic factors, age, sex, and race, the probability of stroke was higher with COVID-19 infection than with influenza infection (OR, 7.6; 95% CI, 2.3-25.2). This high rate of ischemic stroke is consistent with reports from other centers in New York City, as well as in cities around the world that have reported their findings. The thrombotic events that are being observed are likely the cause for the high rate of ischemic stroke in these patients and should be addressed aggressively as part of a comprehensive treatment plan. We do not know what the long-term consequences will be in this population, but there is likely to be a high rate of physical and neurological disabilities.