How common is stroke in people critically ill with COVID-19?
A large, year-long study has found that among people with COVID-19 who were hospitalized in an intensive care unit (ICU), 2% experienced a stroke after they were admitted to the ICU. The preliminary study released today, April 15, 2021, will be presented at the American Academy of Neurology's 73rd Annual Meeting being held virtually April 17 to 22, 2021. The study also found that hemorrhagic stroke, a bleeding stroke, was associated with a higher risk of death among people in the ICU, but ischemic stroke, a stroke caused by a blood clot blocking an artery, was not.
"Stroke has been a known serious complication of COVID-19 with some studies reporting a higher-than-expected occurrence, especially in young people," said study author Jonathon Fanning, M.B.B.S., Ph.D., of the University of Queensland in Brisbane, Australia, and a member of the American Academy of Neurology. "However, among the sickest of patients, those admitted to an ICU, our research found that stroke was not a common complication and that a stroke from a blood clot did not increase the risk of death."
Researchers used an international database of COVID-19 patients in 52 countries admitted to an ICU between January 1 and December 21, 2020. They identified 2,699 people who were admitted to an ICU for management of severe COVID-19 infection. Of those, 59 had a stroke. The people had an average age of 53.
Researchers evaluated the patient data at 370 hospital ICUs and found 59 people, or 2.2%, experienced a stroke during their stay in the ICU. Of those, 19 people, or 32%, had a stroke from a clot, 27 people, or 46%, had a bleeding stroke, and 13 people, or 22%, had an unspecified stroke.
Researchers determined that people who had a bleeding stroke had up to five times greater risk of death than people without stroke. However, people who had a stroke from a clot had no increased risk of death.
Of the people with bleeding stroke, 72% died, but of those, only 15% died of stroke. Instead, multiorgan failure was the leading cause of death.
"For people with COVID-19 in intensive care, our large study found that stroke was not common, and it was infrequently the cause of death," said Fanning. "Still, COVID-19 is a new disease and mutations have resulted in new variants, so it's important to continue to study stroke in people with the disease. More importantly, while the proportion of those with a stroke may not be as high as we initially thought, the severity of the pandemic means the overall absolute number of patients around the world who will suffer a stroke and the ongoing implications of that for years to come, could create a major public health crisis."
A limitation of the study is the variability in how stroke was diagnosed and recorded.