By Ruby Sweeney, June 29, 2022 at 7:30 p.m.
A study led by Western University researchers has revealed the cause of COVID-19 symptoms.
New data published by Western professor Grace Parraga and the LIVECOVIDFREE study, based in five centers in Ontario, is the largest MRI study of patients with COVID-19. The term long-COVID refers to symptoms of brain fog, shortness of breath, fatigue, and a feeling of limitation while doing everyday things, which often last for weeks and months after infection.
This is the first study to show a potential cause of COVID-19, which has helped doctors in the study target patient treatment.
“I think it’s always an enigma when someone has symptoms, but the problem can’t be identified,” said Parraga, a Canada Level 1 research chair in lung imaging to transform the results of the Schulich School of Medicine and Dentistry. . “If you can’t identify the problem, you can’t identify solutions.”
Using magnetic resonance imaging with inhaled xenon gas, researchers have identified that the symptoms are caused by microscopic abnormalities that affect how oxygen is exchanged from the lungs to red blood cells.
The researchers used the technology to observe the function of the 300-500 million small alveolar sacs, which are about 1/5 millimeter in diameter and are responsible for providing oxygen to the blood.
“What we saw on MRI was that the transition from oxygen to red blood cells was depressed in those symptomatic patients who had had COVID-19, compared to healthy volunteers,” Parraga said.
Further CT scans pointed to an “abnormal cut” of the vascular tree, which indicated an impact on the small blood vessels that provide red blood cells to the alveoli to oxygenate them.
Parraga said the study showed no difference in severity between patients who were hospitalized with COVID-19 and those who recovered without hospitalization. He said this is an important finding, as the latest wave of COVID-19 has affected many people who did not receive hospital care.
To conduct the study, researchers recruited patients suspected of having COVID-19 from the COVID-19 Emergency Care Clinic at the London Center for Health Sciences and the COVID-19 Post-Acute Program at St. Joseph’s Health Care London. Some participants experienced persistent shortness of breath more than six weeks after infection, while others were still symptomatic after 35 weeks.
One participant is Alex Kopacz, a Canadian gold medalist with Canadian bobsleigh and a native of London, who described his experience with COVID-19 as “heartbreaking” and believed the virus would not affect him in the long run. since he is a young athlete.
“I was on oxygen for almost two months after COVID, and it took me almost three months to get to a place where I could go for a walk without breathing air,” Kopacz said. “The message that brings me home is that we need to remember that this virus can have very serious long-term consequences, which are not trivial.”
Researchers are conducting a one-year follow-up to better understand these results.
The study was conducted in collaboration with researchers outside London from Lakehead University, McMaster University, Metropolitan University of Toronto and Sick Kids Hospital in Toronto.