Neuroinflammation After COVID-19 With Persistent Depressive and Cognitive Symptoms.

Area of Science:

• Neuroscience
• Psychiatry
• Radiology

Background:

• Persistent depressive and cognitive symptoms, termed COVID-DC, are common after COVID-19 infection.
• Gliosis, an inflammatory brain change, is suspected in COVID-DC but has not been previously quantified.
• Translocator protein total distribution volume (TSPO VT) is a positron emission tomography (PET) marker for gliosis.

Purpose of the Study:

• To investigate if TSPO VT is elevated in specific brain regions of individuals with COVID-DC.
• To assess TSPO VT in the dorsal putamen, ventral striatum, prefrontal cortex, anterior cingulate cortex, and hippocampus.

Main Methods:

• A case-control study involving 20 participants with COVID-DC and 20 healthy controls.
• TSPO VT was measured using [18F]FEPPA PET scans.
• Neuropsychological and psychological tests were used to assess symptoms, focusing on striatal function.

Main Results:

• Individuals with COVID-DC showed significantly greater TSPO VT across all studied brain regions compared to controls.
• Elevated TSPO VT was most pronounced in the ventral striatum (22% higher) and dorsal putamen (20% higher).
• Slower motor speed in COVID-DC patients correlated with higher dorsal putamen TSPO VT.

Conclusions:

• Elevated TSPO VT in patients with COVID-DC provides evidence of increased gliosis in the brain.
• This neuroinflammation, particularly in the ventral striatum and dorsal putamen, may underlie persistent depressive and cognitive symptoms.
• Findings suggest a potential biological mechanism for post-COVID-19 neurological and psychiatric sequelae.