Changes in brain function and abnormal brain activity during fMRI memory tests in people who continue to experience brain fog, memory problems, or other neuropsychiatric symptoms months after receiving a COVID-19 diagnosis.
That’s the finding of a study conducted by researchers at the University of Maryland School of Medicine (UMSOM).
Long COVID, combined with neurologic symptoms, was associated with decreased activity in some brain regions used for memory function and increased activity in others. The results were published today in Neurology, the medical journal published by the American Academy of Neurology.
“Greater activity occurs outside of normal working memory brain networks. We often see changes like this in brain-injured patients: Defects in the brain’s default mode network lead to increased activity in other regions that help maintain brain function,” research leader says Linda Chang, MD, MSProfessor of Diagnostic Radiology and Nuclear Medicine, and Associate Member of the Institute of Human Virology (IHV) at the University of Maryland School of Medicine.
“While our study did not prove that COVID caused these brain changes, there appears to be a strong association with these changes and lingering neuropsychiatric symptoms.” she added.
An estimated 30% of people infected with COVID-19 develop chronic symptoms, known as long-term COVID.More than half of these patients experience cognitive or psychiatric symptoms such as fatigue, difficulty concentrating, feeling depressed and anxious, among the most prevalent symptoms, according to a report published in January Substance Abuse and Mental Health Services Administration.
While some patients resolve these issues within a year or two of diagnosis, others continue to suffer from day-to-day disabilities more than three years after the start of the pandemic. Researchers have been racing to conduct studies to learn more about long-term COVID in these patients in an attempt to develop better treatments.
For the new study, Dr. Chang and her colleagues performed functional neuropsychological assessment on 29 patients who had COVID-19 an average of seven months earlier and who had at least one persistent neuropsychiatric symptom, such as memory loss, depression, or anxiety. MRI scan. Nine of the study participants had COVID-19 infection severe enough to require prior hospitalization. The researchers also performed brain imaging scans on 21 healthy volunteers who had no history of COVID-19 and were similar in age, health status, and vaccination status to long-COVID patients.
All participants were measured for thinking and memory skills, emotional health, motor function, and symptoms of depression, anxiety, fatigue, and pain. They also had functional MRI brain scans, along with tests to assess their working memory. The scans showed which areas of the brain were active during the test.
“Although the majority of people with COVID-19 in our study reported persistent problems with concentration and memory, they scored similarly on various tests of thinking skills as people without a history of COVID-19,” Zhang said. “This may be because their brains compensate for these deficits by using more other parts of the network to maintain their performance. “
However, the long-COVID group did score lower on tests of flexibility and exercise tolerance than the non-COVID group. They also reported more negative emotions, such as anger and sadness, and higher stress levels, and had lower life satisfaction scores than those who had never had COVID. In addition, they scored higher on depression, anxiety, fatigue and pain than the control group. People in the post-COVID group who experienced larger changes in brain activity were more likely to score poorly on many of these symptom domains.
These patients could benefit from neurorehabilitation or psychiatric treatment, and the researchers recommend that doctors consider using these methods to help manage the condition.
There are a few caveats to the study: It was primarily conducted early in the pandemic, when the Delta variant of the SARS-CoV-2 virus was circulating in the United States. The results may not apply to newer coronavirus variants such as Omicron, and it is unclear whether these newer variants have similar effects on the brain. Also, because people who have not previously reported COVID-19 are not tested for antibodies, they may have previously been infected or exposed to the virus without showing symptoms.
The study was funded by the National Institute of Neurological Disorders and Stroke.
Other UMSOM staff and students who served as co-authors on this study include: Meghann Ryan, MS, Huajun Lian, MBBS, PhD, Xin Zhang, MS, Eric Cunningham, BS, Justin Wang, Eleanor Wilson, MD, Edward Herskovits, MD, PhD, Shyam Kottilil, MBBS, PhD, Interim IHV Director, and Thomas Ernst, PhD.
“While this study provides important information about brain function in people with neuropsychiatric symptoms due to prolonged COVID, we now need longitudinal follow-up studies to determine if and when these abnormal imaging patterns normalize, and whether this associated with relief of symptoms,” UMSOM Dean said, Mark T. Gladwin, MDwho is also the Vice Chancellor for Medical Affairs and the John Z. and Akiko K. Bowers Distinguished Professor at the University of Maryland, Baltimore.
