Using TriNetX, an electronic health records network with over 81 million patients, researchers for Lancet Psychiatry, a British medical journal, looked at 236,379 patients who were diagnosed with COVID-19. They found that an estimated 33.62% of them received a neurological or psychiatric diagnosis within six months of testing positive for the virus.
“For the U.S., we’re just a little bit over the one-year anniversary of our first cases,” Dr. Kenneth Tyler, a fellow at the American Academy of Neurology and chair of the University of Colorado School of Medicine’s Department of Neurology, told Yahoo Finance. “When you start to talk about potential longer-term [effects] and what’s their natural history, you’ve got to realize we’re really in early days here and that some things may not be apparent for a while now.”
The first documented case of COVID in the U.S. was announced on January 21, 2020. The study compared patients diagnosed with COVID-19 to patients diagnosed with influenza and patients diagnosed with any respiratory tract infection during the same time period from Jan. 20 to December 13, 2020.
“COVID-19 was robustly associated with an increased risk of neurological and psychiatric disorders in the six months after a diagnosis,” the Lancet Psychiatry study stated. “Given the size of the pandemic and the chronicity of many of the diagnoses and their consequences, substantial effects on health and social care systems are likely to occur … The findings also highlight the need for enhanced neurological follow-up of patients who were admitted to [intensive care units] or had encephalopathy during their COVID-19 illness.”
According to the study, these conditions include intracranial hemorrhage (0.56%), ischemic stroke (2.10%), Parkinson’s Disease (0.11%), dementia (0.67%), anxiety disorder (17.39%), and psychotic disorder (1.40%). There were also instances of Guillain-Barré syndrome; nerve, nerve root, and plexus disorders; neuromuscular junction and muscle disease; encephalitis; substance use disorder; and insomnia.
“What we have to remember is tiny percentages that at first don’t seem very impressive,” Tyler said, “[but] if they’re magnified over an infection that has literally affected millions of people and continuing to climb throughout the world, that can generate a pretty fair burden of disease.”
'Your heart can throw really tiny clots into your brain'
There have been previous signs of neurological issues stemming from COVID.
According to one study published in the Annals of Clinical and Translational Neurology, 85 of the 100 patients examined experienced at least four or more neurological effects following their diagnosis. These symptoms included brain fog, headaches, numbness/tingling, muscle pain, and dizziness.
“We’ve been seeing a lot of the neurological disorders,” Dr. Suzanne Judd, a professor at the University of Alabama at Birmingham School of Public Health, told Yahoo Finance. “When COVID first hit, the people were talking about the cardiac conditions or heart conditions, but now we’re starting to hear more and more talk about stroke and other neurological diseases, [and] some of the blood clot disorders, like blood clots in the legs and in the lungs.”
Blood clots are one of the main causes of intracranial hemorrhages (brain bleeds), one of the neurological effects seen as a result of a COVID-19 diagnosis. Intracranial hemorrhages occurred in 2.66% of patients who had to be admitted into intensive care units because of COVID.
“The interesting thing about stroke [is] if it does have something to do with blood clots, your heart can throw really tiny clots into your brain,” Judd said. “That leads to all kinds of conditions afterwards — memory loss, full-on stroke where one side of your body can lose the ability to open bottles and move, lose the ability to communicate and the ability to understand, and all of those things wind up being associated with mental health.”
Many of these other neurological symptoms mimic those of concussions or traumatic brain injuries, according to the New York Times. When the body reacts to the virus, the inflammatory response affects all parts of the body, including the brain.
“At the first level, the first that you’d see increased incidents of some of these things, including stroke, which has been well-recognized, it isn’t surprising,” Tyler said. “To me, what’s more surprising — we’re starting to get into that area of, ‘boy these aren’t things we typically see as an acute manifestation.’ We’re maybe starting to see a signal in this study that the answer to that could be yes.”
'Absolutely' could become a serious problem
More severe neurological symptoms correspond with a higher risk of developing other complications, according to Tyler.
“There was an impressive incidence of things like anxiety — maybe not super surprising — but this interesting thing that’s caught a lot of attention is the onset of really severe psychotic diseases,” he said. “We’ve now seen that patients without a pre-existing history of major psychiatric illness are suddenly developing it in the context of COVID.”
The Lancet study noted that compared to a previous report published back in September 2020, there was an increased risk of psychotic disorders this time around. Substance use disorders and insomnia were also more prevalent among COVID survivors than those who had the flu or other respiratory tract infections.
“Therefore,” the researchers wrote, “as with the neurological outcomes, the psychiatric sequelae of COVID-19 appear widespread and to persist up to, and probably beyond, six months. Compared with neurological disorders, common psychiatric disorders (mood and anxiety disorders) showed a weaker relationship with the markers of COVID-19 severity in terms of incidence.”
Judd said she “absolutely” sees this becoming a serious problem, especially for those who were hospitalized because of the virus.
“Hospitalization can be very traumatic,” she said. “Intubation with a ventilator is extremely traumatic. People could have conditions that mimic PTSD without a doubt. So that could be part of what it is, too. If a person was hospitalized, if they were home, it would be a little more difficult to look for evidence to see if something about having COVID in and of itself is different than another infectious disease or other illness in terms of producing trauma on the body.”
Adriana Belmonte is a reporter and editor covering politics and health care policy for Yahoo Finance. You can follow her on Twitter @adrianambellsand reach her at firstname.lastname@example.org.