Research on long COVID | Hope for women with chronic fatigue syndromes

Research on long COVID could benefit other fatigue syndromes that follow infections. These disorders, which are difficult to diagnose and treat, affect twice as many women as men. A symbol of sexism in medicine?

“When we started talking about long COVID, at the end of 2020, patients pointed out to me how close it was to their symptoms,” explains Madeleine Durand, an epidemiologist at the University of Montreal who studied a cohort Quebec population of patients with long COVID. “These are patients who have had chronic fatigue, mental fog and abnormally low resistance to exercise for years. Often, doctors told them it was all in their heads. These are called “non-specific” symptoms. There are no tests to make a diagnosis. »

These problems are often grouped together under the term “post-acute infection syndrome”. “The idea is that there are things that have changed with the infection, and that there remain after-effects that we cannot currently measure,” says the D^D Durand. As many people have had COVID-19, there are many cases of long COVID. We are talking about 15% of COVID-19 cases. So there’s a lot of funding for long COVID. »

Sexism

According to the D^D Durand, the fact that these syndromes affect women more, like long COVID, has contributed to their “trivialization” by medicine. “Historically, doctors have not always responded well to issues that specifically affect women. »

A patient from the D^D Durand, Marie-Christine Michaud, recognized herself when reading the first descriptions of long COVID. Her career as a CPA accountant at a bank was derailed about a decade ago, when she was in her mid-30s, because of what looks like post-acute infection syndrome. “It really compromised my professional and social life,” says M.^me Michaud.

At first, many also believed that long COVID was psychosomatic, according to Douglas Fraser, an epidemiologist at Western University in London, Ontario, who discovered a molecule associated with long COVID. “But with the number of cases that we have seen, it is now ruled out,” explains the D^r Fraser. The problem with finding a biomarker, a molecule associated with long COVID that could be used for diagnosis, is that there is a lot of variation. In Africa, for example, in countries where many people have HIV, long COVID has a different presentation. »

Even if the diagnostic tools and treatments that may be discovered for long COVID are not applicable to other post-acute infection syndromes, this research has the great merit of giving credit to those who suffer from it. “One of the difficult things for patients is not having a diagnosis, not being recognized,” says the D^D Durand.

Three mechanisms

Three mechanisms could be responsible for long COVID and potentially other post-acute infection syndromes, according to Ian Lipkin, an epidemiologist at Columbia University in New York, who has published several analyzes on the issue: vascular damage to different organs , metabolism problems and autoimmune reactions. “We know that COVID-19 affects very small blood vessels,” says Dr.^r Lipkin. Depending on the organs affected, the effects may be different. We also know that SARS-CoV-2 [le coronavirus responsable de la COVID-19] affects mitochondria [les usines énergétiques des cellules]. So we can think that it will alter the body’s metabolism, fatigue, resistance to exercise, mental fog. Finally, there may be abnormal, chronic activations of the immune system, which prevent the body from functioning normally. »

Post-acute infection syndromes that may be similar to long COVID include controversial disorders. The famous geneticist Eric Topol, from the Scripps Institute in California, recently published in Science a comment accompanying the description of a biomarker for long COVID in which he mentioned a link between the Epstein-Barr virus, responsible for mononucleosis, and multiple sclerosis. The study that established this link in 2022 is highly contested even though it was published in the journal Scienceestimates Alexandre Prat, neurologist from the University of Montreal.

Lyme disease is also often mentioned in scientific articles on the similarity between long COVID and post-infectious syndromes. “Indeed, the symptoms are similar,” says the D^D Durand. In addition, as with other post-viral fatigue syndromes, there is not yet a recognized diagnostic test or treatment supported by evidence. It is important that people who suffer from it have access to research, as for all those who suffer from post-infectious syndromes. Without proper research, people are at risk of suffering side effects from treatments that aren’t even effective. »

And long COVID in all this? The D^r Western’s Fraser is participating in “a large, multi-continental study” to find other biomarkers for long COVID. The D^D Durand reproduced the results of the D biomarker with Quebec patients^r Fraser. And last November, Ontario pharmaceutical company Revive Therapeutics announced it was working on a long-COVID test based on results from Western University.