Research out of the University of Alberta (U of A) may explain why women are three times as likely as men to develop long COVID. Long COVID, as post-COVID-19 condition is colloquially called, is defined in Canada by the persistence of symptoms for more than 12 weeks after SARS-CoV-2 infection. Such symptoms can include fatigue, cognitive problems and more. In June 2023, 3.5 million Canadians reported having long COVID. While studies have identified a higher diagnosis rate among women, U of A immunology professor Shokrollah Elahi noticed this in his own clinic. By studying blood and genetic test results of 78 long-COVID patients one year after their acute diagnosis, as well as that of 62 people who did not develop long COVID after COVID-19, Elahi and his team identified three potential reasons for the difference. First, in the female long-COVID patients, Elahi found signs of gut inflammation, suggesting at the acute SARS-CoV-2 stage, they are more prone to viral infection. “If the gut gets infected at the earlier stage and it results in inflammation and damage to the gut, it may result in a small leakiness. And that leakiness may drive the chronic inflammation, and chronic inflammation can contribute to long COVID,” Elahi explained in an interview on Monday. Second, the women also had lower red blood cell production or anemia, suggesting inflammation adversely affects blood production. Third, Elahi’s team found that long-COVID patients had dysregulated sex hormones: low testosterone in women, decreased estrogen in men, and low cortisol in both. Further, women who had lower testosterone levels had more inflammation and low testosterone was linked to symptoms like brain fog, depression, pain and fatigue. Their findings have not been tested in a clinical trial but they do align with previous research into the presence of chronic inflammation in chronic fatigue syndrome, which disproportionately affects women, and anemia as a factor in long COVID. Since publishing the research, Elahi said he’s heard from female long-COVID patients who were taking testosterone supplements for other reasons and noticed a difference in their symptoms. “They were able to function, their brain fogginess has disappeared,” the immunologist told CTV News Edmonton. The research suggests long COVID potentially be treated with anemia treatments, anti-inflammatory drugs or sex hormones. Elahi is now seeking funding for a clinical trial. With files from CTV News Edmonton’s Gates Guarin