It is one of many mysteries about long COVID: Who is more prone to developing it? Are some people more likely than others to experience physical, neurological or cognitive symptoms than can emerge, or linger for, months after their coronavirus infections have cleared?
Now, a team of researchers who followed more than 200 patients for two to three months after their COVID diagnoses report that they have identified biological factors that might help predict if a person will develop long COVID.
The study, published Tuesday by the journal Cell, found four factors that could be identified early in a person’s coronavirus infection that appeared to correlate with increased risk of having lasting symptoms weeks later.
The researchers said they had found that there was an association between these factors and long COVID (which goes by the medical name post acute sequelae of COVID-19, or PASC) whether the initial infection was serious or mild. They said that the findings might suggest ways to prevent or treat some cases of long COVID, including the possibility of giving people antiviral medications soon after an infection has been diagnosed.
“It’s the first real solid attempt to come up with some biologic mechanisms for long COVID,” said Dr. Steven Deeks, a professor of medicine at the University of California, San Francisco, who was not involved in the study.
He and other experts cautioned that the findings were exploratory and would need to be verified by considerably more research.
One of the four factors researchers identified is the level of coronavirus RNA in the blood early in the infection, an indicator of viral load. Another is the presence of certain autoantibodies — antibodies that mistakenly attack tissues in the body as they do in conditions like lupus and rheumatoid arthritis. A third factor is the reactivation of Epstein-Barr virus, a virus that infects most people, often when they are young, and then usually becomes dormant.
The final factor is having Type 2 diabetes, although the researchers and other experts said that in studies involving larger numbers of patients, it might turn out that diabetes is only one of several medical conditions that increase the risk of long COVID.
Pam Belluck@c.2022 The New York Times Company