Bijoy Menon’s patient came down with a cough and fever, but was not terribly ill. Three days later, the 45-year-old man, who worked at a meat-packing facility, was rushed to hospital by ambulance with a major stroke, unable to speak and move his arm and leg.
This severe stroke case is one of three that Dr. Menon, a stroke neurologist at Calgary’s Foothills Medical Centre, has seen in recent weeks among unusually young and relatively healthy patients. All are between their late-30s and mid-40s. All were either suspected of being infected by the new coronavirus or have tested positive.
“Obviously, you don’t want to see somebody so young having a stroke,” says Dr. Menon, an associate professor at the University of Calgary. “It affects your brain, and ... we are who we are because of our brain.”
As the new coronavirus continues to spread, doctors and researchers are finding new and varied complications linked to the disease it causes, from “COVID toes,” or frostbite-like patches on the feet, to a rare inflammatory syndrome in children. Reports of stroke in patients under age 50, or who have no traditional risk factors for stroke, such as high blood pressure or diabetes, add to the list of phenomena believed to be related to COVID-19 that scientists are trying to understand.
In a widely circulated case report in The New England Journal of Medicine last week, doctors at Mount Sinai Health System in New York described seeing five patients, under age 50, within a two-week period with large-vessel ischemic stroke, or blood clots blocking a main vessel of the brain. All tested positive for COVID-19. By contrast, they wrote, they typically treat fewer than one such patient within a two-week period.
Though these cases represent a small number, Adam Dmytriw, a Toronto physician and student at the Harvard School of Public Health, believes there may be many more COVID-19-related strokes out there.
Dr. Dmytriw is part of a team collecting data from hospitals in the United States and Canada, including Foothills Medical Centre, on strokes occurring in patients amid the pandemic who are under age 50 or do not have traditional risk factors for stroke. At about eight health centres enrolled so far, he says, there have been 30 such cases. (Dr. Menon says two of his patients, who were suspected of having COVID-19, ended up testing negative. But because their strokes could not be explained, they were included in the data set, he says, noting it is possible for tests to result in false-negatives.)
Dr. Dmytriw says data from several New York-area hospitals suggest these strokes disproportionately affect those who are low-income and minorities, particularly black individuals. This may partly be because physical distancing can be more difficult for those in dense living environments, and because individuals in these communities tend to delay seeking medical help, he says, noting it’s unknown whether genetics play a role.
Moreover, he says, many of the stroke patients have mild or no symptoms of COVID-19, such as cough and shortness of breath.
“Unfortunately, part of the issue is that people are being told to go on self-isolation. They’re sitting in their apartment, and then they wake up with the inability to move half of their body or speak,” he says, adding these younger patients are often breadwinners for their families. “They get this out of nowhere, thinking they’re doing everything right.”
In New York, vascular neurologist Ambooj Tiwari, who is leading this consortium of health centres sharing stroke data, says the youngest stroke patient he encountered was a 27-year-old emergency medical technician, who tested positive for COVID-19 after coming down with a mild fever. The man went into self-quarantine at home for three or four days, before experiencing a stroke because of a blockage of a main artery of the brain.
“When I got a call about the case, I was absolutely confused because the guy had no medical history whatsoever,” says Dr. Tiwari, a clinical assistant professor at New York University, who also works at Brookdale Hospital University Medical Centre and Jamaica Hospital Medical Centre in New York.
Increasingly, he says, researchers believe it’s not just a coincidence that hypercoagulable conditions, or blood clotting problems, are occurring in patients with COVID-19.
Dr. Dmytriw explains they believe the virus, which has been found to target a specific receptor called ACE-2 in cells on blood vessel walls, may be attacking the vessel wall and causing massive clotting. In a stroke, a clot enters the brain, blocking off blood supply and causing cell death. Doctors are seeing similar effects elsewhere in the bodies of various patients, such as in the heart and lungs, he says.
Fabio Settecase, a clinical assistant professor of radiology at the University of British Columbia, says there are a number of other possible explanations. For instance, in certain individuals, the virus may cause significant inflammation, the body’s immune response, which in turn, causes the clotting system to become dysfunctional, he says.
Dr. Settecase, who is a neurointerventional radiologist, says he has seen around five stroke patients at Vancouver General Hospital with COVID-19, though none were under age 50. Stroke in young and otherwise healthy adults appears to be rare, he says.
“What's important to take away is that stroke can be a sign of COVID infection in a small number of patients,” he says.
Amy Yu, a stroke neurologist at Toronto’s Sunnybrook Health Sciences Centre, says while it’s important for front-line health care providers to share their observations, it is still too early to draw any conclusions about the link between COVID-19 and stroke, since there is not yet enough data.
As more people become infected, Dr. Yu says she expects to see patients with both COVID-19 and stroke, since strokes that would normally occur will continue to occur during the pandemic.
Dr. Yu emphasizes that anyone experiencing symptoms of a stroke should seek immediate medical attention. “Hospitals are still safe, and if there is a medical emergency, they should still be coming to the hospital,” she says.
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