One study showed a stroke rate of 2.2% among patients with COVID-19 admitted to intensive care in 52 different countries. Another found a stroke rate of 1.48% in patients hospitalized with COVID-19 from 70 different countries. These researchers also found a reduction in stroke presentations and stroke care during the pandemic.
Both studies will be presented at the American Academy of Neurology’s 2021 annual meeting.
“Stroke has been a known serious complication of COVID-19, with some studies reporting a higher-than-expected occurrence, especially in young people,” said coauthor of the intensive care study, Jonathon Fanning, MBBS, PhD, University of Queensland, Brisbane, Australia.
“However, among the sickest of COVID patients – those admitted to an ICU – our research found that stroke was not a common complication and that ischemic stroke did not increase the risk of death,” he added.
Hemorrhagic stroke more common?
In this study, researchers analyzed a database of 2,699 patients who were admitted to the intensive care unit with COVID-19 in 52 countries and found that 59 of these patients (2.2%) subsequently sustained a stroke.
Most of the strokes identified in this cohort were hemorrhagic (46%), with 32% being ischemic and 22% unspecified. Hemorrhagic stroke was associated with a fivefold increased risk for death compared with patients who did not have a stroke. Of those with a hemorrhagic stroke, 72% died, but only 15% died of the stroke. Rather, multiorgan failure was the leading cause of death.
There was no association between ischemic stroke and mortality.
“There is scarce research on new-onset stroke complicating ICU admissions, and many of the limitations of assessing stroke in ICU populations confound the true values and result in variability in reported incidence anywhere from a 1%-4% incidence,” Dr. Fanning said.
He noted that a large Korean study had shown a 1.2% rate of stroke in patients without COVID admitted to non-neurologic ICUs. “In light of this, I think this 2% is higher than we would expect in a general ICU population, but in the context of earlier reports of COVID-19–associated risk for stroke, this figure is actually somewhat reassuring,” Dr. Fanning said.
Asked how this study compared with the large American Heart Association study recently reported that showed an overall rate of ischemic stroke of 0.75%, Dr. Fanning said the two studies reported on different populations, which makes them difficult to compare.
“Our study specifically reports on new-onset stroke complicating ICU admission,” he noted. “The AHA study is a large study of all patients admitted to hospital, but both studies identified less than previous estimates of COVID-related stroke.”
Largest sample to date
The other study, which includes 119,967 COVID-19 hospitalizations and represents the largest sample reporting the concomitant diagnoses of stroke and SARS-CoV-2 infection to date, was presented at the AAN meeting by Thanh N. Nguyen, MD, a professor at Boston University.
This study has also been published online in Neurology, with first author Raul G. Nogueira, MD, Emory University, Atlanta.
In this international observational, retrospective study across 6 continents, 70 countries, and 457 stroke centers, there was a 1.48% stroke rate across 119,967 COVID-19 hospitalizations. SARS-CoV-2 infection was noted in 3.3% (1,722) of all stroke admissions, which numbered 52,026.
The researchers identified stroke diagnoses by the International Classification of Diseases, 10th revision, codes and/or classifications in stroke center databases, and rates of stroke hospitalizations and numbers of patients receiving thrombolysis were compared between the first 4 months of the pandemic (March to June 2020) compared with two control 4-month periods.