COVID-19 has been unpredictable as more is learned about the varied side effects of the virus. A typical respiratory infection, such as the flu, usually has a specific set of symptoms and potential complications. With COVID-19, the long-term effects range from neurological complications to loss of taste and smell, trouble focusing (“brain fog”), and chronic fatigue.
Another surprising finding from several studies is the heightened risk of stroke and heart attack—and not just for older adults. People under the age of 50 appear to be at much higher risk of these complications too.
One study published in JAMA in April 2021 found that the risk of stroke was more than twice as high for COVID-19 patients when compared to people of the same age, sex, and ethnicity in the general population—82.6 cases per 100,000 people compared to 38.2 cases for those without a COVID-19 diagnosis.
In another Swedish study published in the August 14, 2021 issue of The Lancet, researchers found that within a week of a COVID-19 diagnosis, a person’s risk of heart attack was three to eight times higher than normal, and their risk of stroke was three to six times higher. The study revealed these risks remained high for at least a month. The average age of people in the study was only 48 years. The data from those diagnosed was compared with 348,000 Swedish people in a similar age range who did not have the virus. Research published in 2023 suggests that SARS-Cov2 increases inflammation in arterial walls in the heart, potentially explaining how COVID-19 increases risk for heart attack and stroke.
This trend is something Jonathan Kinzinger, DPT, a physical therapist and adjunct assistant professor at University of Utah Health who works with stroke patients at the Craig H. Neilsen Rehabilitation Hospital, has seen up close.
“We are definitely seeing a huge increase in younger stroke survivors who are post-COVID diagnosis,” Kinzinger says. “We know that vascular complications go along with COVID infections, which can lead to strokes and other cardiovascular issues.”
A group of researchers headed by Mark Ellul, PhD, NIHR Clinical Lecturer in Neurology at the Institute of Infection, Veterinary and Ecological Sciences from the University of Liverpool, first observed this in September 2020. They found that the number of patients admitted to the hospital with a large vessel stroke who also had a COVID-19 diagnosis was seven times higher than normal.
Similar findings have also come out of other countries, where the median age for patients who needed thrombectomy surgery to remove a blood clot was down across the board. In one New York Medical Center, the average age of patients with confirmed stroke and COVID-19 diagnosis was 63 years. The average age of stroke patients who tested negative for COVID was much higher (70 years), even when they controlled for age, sex, and other risk factors.
Researchers are still studying the cause of the increased risk. But doctors know that COVID-19 causes an inflammatory response that thickens a person’s blood. Thicker blood is more likely to clot, and clots can lead to stroke. Many of the young people who suffer a stroke after a COVID-19 diagnosis have few (and sometimes no) risk factors normally associated with stroke.
Sometimes these strokes don’t occur for several weeks after a COVID-19 diagnosis, and it’s impossible to predict who might be at risk. For patients recovering from COVID-19 and a stroke, there is the added challenge of an impaired cardio-respiratory system. “Not only are we dealing with strength, motor, and balance deficits that go along with stroke, we also have to work around respiratory issues, tracheostomies, and other complications,” Kinzinger says. Stroke recovery is physically and mentally challenging anyway, and these complications can increase recovery time.
“When someone has a stroke and they are under 50, their whole life is uprooted,” he says. “A lot of people have younger kids or spouses, they may have a career or they’re going to school, so it’s just such a different phase of life than someone who is older.”