“These markers have been looked at in other COVID populations, but our study population was unique because we have matched cognitive and quality-of-life measures in addition to the typically studied COVID symptoms like shortness of breath, fatigue and brain fog,” said Dr. Igor Koralnik, chief of Neuro-infectious Diseases and Global Neurology at Northwestern Medicine.
“The most noteworthy finding is that we were able to look at a marker of nerve cell damage and a marker of activation of supporting cells in the brain called ‘glial cells’ which are elevated in other diseases of the brain such as multiple sclerosis.”
Koralnik and his team looked at 64 participants, including hospitalized COVID-19 patients at Northwestern with acute brain dysfunction, non-hospitalized COVID long-haulers treated at Northwestern’s Neuro COVID-19 clinic run by Koralnic, and healthy control subjects from the community.
Both long-haulers with symptoms of anxiety and COVID patients hospitalized at Northwestern Memorial with encephalopathy, the most severe neurologic manifestation of COVID-19, showed evidence of neuron damage and brain inflammation.
The evidence of a biological basis for the neuropsychiatric symptoms in long haulers may be helpful in validating these patients’ experiences, the statement said, which is welcome because COVID long-haulers often express frustration that their lingering complaints are often dismissed.
“The correlation we observed between anxiety and neuro-glial score held up when we controlled for age, sex and BMI, and was observed in both qualitative and quantitative measures of anxiety, which suggests there is a true relationship,” said Barbara Hanson, who co-authored the study and analyzed the data in the Northwestern Medicine Neuro COVID-19 research lab. “We hope the observed correlation leads to future research into the mechanistic basis of these neuropsychiatric symptoms in long-COVID patients, or perhaps in the biological basis of chronic anxiety in general.”
Neurological problems for both hospitalized COVID patients and long-haulers who weren’t hospitalized seem rampant, the Northwestern Medicine Neuro COVID-19 research group has found. In October 2020, its research showed neurological manifestations in 82% of hospitalized patients studied. In March 2021, the group found that 85 of 100 non-hospitalized COVID long-haulers experienced four or more neurologic symptoms that impacted their quality of life and, in some patients, their cognitive abilities.