Researchers Suspected Brain Inflammation in Long COVID but Found Something Else

Key Points:

• A Finnish brain imaging study found no evidence of widespread neuroinflammation in people with long COVID compared to healthy controls, challenging the idea that persistent brain inflammation drives long COVID symptoms.
• The study involved PET and MRI scans of 14 long COVID patients, 11 healthy volunteers, and 13 multiple sclerosis patients, revealing that inflammatory activity in long COVID patients’ brain white matter was much lower than in MS patients.
• Inflammatory activity appeared higher in long COVID patients scanned within 16 months of infection, suggesting brain inflammation may be more prominent early in the illness and decline over time.
• Increased cellular activity was observed in the hippocampus and amygdala—brain regions involved in emotion regulation—in patients reporting higher anxiety, depression, and poorer quality of life, linking emotional brain areas to symptom severity.
• Researchers suggest that long COVID symptoms may involve complex biological mechanisms beyond inflammation, indicating potential benefits from treatments focused on stress management and emotional regulation rather than solely anti-inflammatory therapies.