Neurology experts warn of COVID-19's mysterious effects on the brain

During the COVID-19 pandemic, medical experts have often stressed, "We still have a lot to learn about this new disease." That includes its effects on the brain, which is the subject of a Washington Post article by neurology experts Serena S. Spudich and David A. Hafler.

Spudich is a neurology professor at Yale University in New Haven, Connecticut, while Hafler chairs Yale's neurology department. In a Post article published this week, Spudich and Hafler don't pretend to be the last word on the neurological effects of COVID-19 — which was first reported in China in December 2019. And they point out that there are "many unknowns of how the virus may impact the brain." But their research and observations are well worth noting.

"There might be consequences of infection that we did not originally predict," Spudich and Hafler explain. "Many patients in our clinics complain months after recovering from the disease of difficulty with concentration, finding words and completing complicated tasks. Given that more than 100 million people worldwide have been infected by the novel coronavirus, how the disease affects the brain might be the neurologic research question of our time."

Spudich and Hafler note that when they began studying COVID-19's effects on the brain in March 2020 — almost a year ago — they observed "a panoply of different conditions," including "patients who woke up too slowly after long stays in intensive care, who experienced new strokes and who suffered unbearable headaches."

"The good news was that the severe confusion, headaches and other acute neurologic symptoms for most patients improved as they recovered in the hospital," Spudich and Hafler recall. "But as the weeks wore on, we began to notice new syndromes, many of which seemed to persist or even emerge days or weeks after the illness. We learned of new headaches that wouldn't go away and disturbing changes in sensation on the skin all over the body. Individuals with no prior mood problems reported severe depression or anxiety that interfered with sleep or even caused thoughts of suicide."

The Yale neurology experts add, "Frustrated health-care providers and students found going back to their routines at work or school challenging due to difficulties with concentration and multitasking. Patients even presented to our emergency services with new psychoses that unexpectedly emerged, including paranoia, delusions and violent behavior."

Spudich and Hafler emphasize that a lot more research on COVID-19's effects on the brain needs to be conducted, including how it affects "migraine headaches" or "memory disorders."

"We need large, systematic studies to characterize and determine the frequency of and risk factors for these symptoms, including in races and ethnicities that have been disproportionally affected by the pandemic," Spudich and Hafler note. "Essential to these studies will be defining the biological underpinnings of these syndromes, to help develop targeted treatments."

The COVID-19 death count, according to Johns Hopkins University researchers, has passed 2.4 million worldwide and 493,600 in the United States. But as tragic as those figures are, they don't tell the whole story — as COVID-19 survivors can suffer debilitating long-term symptoms.

"The demographics of patients we see in our clinic with post-COVID-19 neurologic syndromes are worrisome," Spudich and Hafler warn. "Many are young and otherwise healthy people. Early in the pandemic, we were concerned about long-term brain health in patients who had prolonged stays in intensive care, but in our experience, such symptoms occur even in patients who experienced mild disease and were never hospitalized. Death rates do not tell the full story; survival after COVID-19 infection might not be completely straightforward."