Scientists foggy on why virus leads to brain fog
After contracting the coronavirus in March, Michael Reagan lost all memory of his 12-day vacation in Paris, even though the trip was just a few weeks earlier.
Several weeks after Erica Taylor recovered from her COVID-19 symptoms of nausea and cough, she became confused and forgetful, failing to even recognize her owncar, the onlyToyota Prius in her apartment complex’s parking lot.
Lisa Mizelle, a veteran nurse practitioner at an urgent care clinicwhofell ill with the virus in July, finds herself forgetting routine treatments and lab tests and has to ask colleagues about terminology she used to knowautomatically.
“I leave the room, and I can’t remember what the patient just said,” she said, adding that if she hadn’t exhausted her medical leave she’d take more time off.
“It scares me to think I’m working,” Mizelle, 53, said. “I feel like I have dementia.”
It’s becoming known as COVID brain fog: troubling cognitive symptoms that can include memory loss, confusion, difficulty focusing, dizziness and grasping for everyday words. Increasingly, COVID survivors say brain fog is impairing their ability to work and function normally.
“There are thousands of people who have that,” said Dr. Igor Koralnik, chief of neuro-infectious disease at Northwestern Medicine in Chicago, who has already seen hundreds of survivors at a post-COVID clinic he leads. The effect on the workforce that is affected is going to be significant, he added.
Scientists aren’t sure what causes brain fog, which varies widely and affects even people who became only mildly physically ill from COVID-19 and had no previous medical conditions. Leading theories are that it arises when the body’s immune response to the virus doesn’t shut down or from inflammation in blood vessels leading to the brain.
Confusion, delirium and other types of altered mental function have occurred during hospitalization for COVID-19 respiratory problems, anda study found such patients needed longer hospitalizations, had higher mortality rates and often couldn’t manage daily activities right after hospitalization.
But research on longlasting brain fog is just beginning. A French report in August on 120 patients who had been hospitalized found that 34% had memory loss and27% had concentration problems months later.
In a soon-to-be-published survey of 3,930members of Survivor Corps, a group of people who have connected to discuss life after COVID, more than half reported difficulty concentrating or focusing, said Natalie Lambert, an associate research professor at Indiana University School of Medicine, who helped lead the study. It was the fourthmostcommonsymptomout of the 101 long-term and short-term physical, neurological and psychological conditions that survivors reported. Memory problems, dizziness or confusion were reported by one-third or more respondents.
“It is debilitating,” said Rick Sullivan, 60, of Brentwood, California, who has had episodes of brain fog
since July after overcoming a several-week bout with COVID-19 breathing problems and body aches. “I become almost catatonic. It feels as though I am under anesthesia.”
When Taylor, 31, contracted the virus in midJune, she thought she’d need only a brief break from working as a lawyer for an Atlanta nonprofit helping low-income tenants.
But she became so disoriented that she washed her TVremotewith her laundry and had to return a foster dog she’d recently taken in because she couldn’t trust herself to care for a pet.
One morning, “everything inmy brainwas white static,” she said. “I was sitting on the edge of the bed, crying and feeling, ‘Something’s wrong; I should be asking for help,’ but I couldn’t remember who or what I should be asking. I forgot who I was and where Iwas.”
By July, shethought she’d improved and told her boss she could return. But after another “white static” episode, she messaged him: “‘I’m scared. I really want to get back to work. But, I keep getting really tired and really confused.’ ” He suggested she rest and heal.
She resumed working in early August, but her mind wandered, and reading emails was “like reading Greek,” she said. By September, 46,614
her employer urged a 13-week leave.
Reagan, 50, who spent five days in and out of hospitals, initially resumed work as a vascular specialist for a company that makes stents and catheters.
But finger tremors and seizures, neurological symptoms that sometimes accompany brain fog, meant “there is no way I’m going to go into surgery and teach a doctor how to suture an artery,” he said.
In meetings, “I can’t find words,” said Reagan, who has now taken a leave. “I feel like I sound like an idiot.”
Brain fog’s cause is a mystery partly because symptoms are so varied.
“The simplest answer is, people still have persistent immune activation after the initial infection subsided,” said Dr. Avindra Nath, chief of infections of the nervous system at theNational Institute of Neurological Disorders and Stroke.
Tiny strokes may cause some symptoms, said Dr. Dona KimMurphey, a neurologist and neuroscientist, who herself has experienced post-COVID neurological issues, including “alien hand syndrome,” in which she felt a “superbizarre sense of my left hand, like I didn’t understand why itwas positioned the way it was, and I was really captivated by it.”