Study of Patients With a Chronic Fatigue Condition May Offer Clues to Long Covid

Jennifer Caldwell was active and energetic, working two jobs and taking care of her daughter and her parents, when she developed a bacterial infection that was followed by intense lightheadedness, fatigue and memory problems.

That was nearly a decade ago, and she has since struggled with the condition known as myalgic encephalomyelitis/chronic fatigue syndrome, or ME/CFS. Ms. Caldwell, 56, of Hillsborough, N.C., said she went from being able to ski, dance and work two jobs as a clinical research coordinator and a caterer to needing to stay in bed most of every day.

“I haven’t been right since, and I haven’t worked a day since,” said Ms. Caldwell, whose symptoms include severe dizziness whenever her legs are not elevated.

The condition has also “messed me up cognitively,” she said. “I can’t read something and comprehend it very well at all, I can’t remember new things. It’s kind of like being in a limbo state. That’s how I describe it, lost in limbo.”

Seven years ago, the National Institutes of Health began a study of patients with ME/CFS, and Ms. Caldwell became one of 17 participants who engaged in a series of tests and evaluations of their blood, bodies and brains.

Findings from the study, which was published on Wednesday in the journal Nature Communications, showed notable physiological differences in the immune system, cardio-respiratory function, gut microbiome and brain activity of the ME/CFS patients compared with a group of 21 healthy study participants.