New neurologic issues less likely after severe COVID than flu, research suggests

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Adults hospitalized for COVID-19 were at lower risk of needing medical care for migraine, epilepsy, neuropathy, movement disorders, stroke, and dementia in the next year than matched patients with influenza, researchers from Yale University and the University of Michigan report in Neurology.

They point out, however, that their study did not assess the effects of long COVID.

The investigators analyzed the electronic medical records of 77,272 COVID-19 patients hospitalized from April 2020 to November 2021 and the same number of flu patients admitted from 2016 to 2019 to quantify neurologic diagnoses and related healthcare use in the year after infection. The average patient age was 51 years, 57.7% were women, and 41.5% were White.

36% lower odds of movement disorders

New-onset neurologic conditions were diagnosed in 2.8% of the COVID-19 group and 4.9% of flu patients (HR, 0.62). A lower proportion of COVID-19 patients than flu patients needed care for migraine (2.0% vs 3.2%, respectively; hazard ratio [HR], 0.65), epilepsy (1.6% vs 2.1%; HR, 0.78), neuropathy (1.9% vs 3.6%; HR, 0.57), movement disorders (1.5% vs 2.5%; HR, 0.64), stroke (2.0% vs 2.4%; HR, 0.90), and dementia (2.0% vs 2.3%; HR, 0.93).

While the results were not what we expected to find, they are reassuring in that we found being hospitalized with COVID did not lead to more care for common neurologic conditions when compared to being hospitalized with influenza.

Brian Callaghan, MD, MS

After adjustment for potential confounding factors, COVID-19 patients had a lower risk of requiring care for migraine (-35%), epilepsy (-22%), neuropathy (-44%), movement disorders (-36%), stroke (-10%), and dementia (-7%) than the flu cohort.

The study didn't specifically examine long-COVID outcomes, and the findings don't necessarily conflict with those of previous studies showing increased neurologic symptoms in long-COVID patients, the authors noted. Also, the results may not apply to all COVID-19 survivors because the studied sample wasn't nationally representative.

"While the results were not what we expected to find, they are reassuring in that we found being hospitalized with COVID did not lead to more care for common neurologic conditions when compared to being hospitalized with influenza," coauthor Brian Callaghan, MD, MS, of the University of Michigan Health at Ann Arbor, said in a press release from the American Academy of Neurology, publisher of Neurology.

It's reassuring that COVID-19 behaves similarly to other respiratory viruses with respect to the studied neurologic conditions, the authors said. "There was concern that the already limited access to neurologic care would further shrink if we had a dramatic increase in neurologic care after COVID-19 infection," lead author Adam de Havenon, MD, MSc, of Yale, said in the release.