Summary: <\/strong>A precision neuroimaging study challenged the widely held hypothesis that widespread, persistent brain inflammation is the primary driver of Long COVID. The research used advanced PET and MRI scans to compare Long COVID patients against both healthy controls and multiple sclerosis (MS) patients.<\/p>\n The data revealed no significant differences in long-term neuroinflammation or neurodegeneration between Long COVID subjects and healthy controls. Instead, the findings expose a time-dependent disease profile where brain inflammation peaks early post-infection and naturally diminishes over time, shifting the therapeutic focus toward emotional and stress regulation networks.<\/p>\n Key Facts<\/strong><\/p>\n Source: <\/strong>University of Turku<\/p>\n Long COVID has been suspected to involve persistent brain inflammation following SARS-CoV-2 infection, potentially explaining symptoms such as fatigue, cognitive impairment, anxiety, and depression. While previous studies have suggested this possibility, direct evidence has been limited.<\/strong><\/p>\n Researchers at the University of Turku, Finland, used advanced brain imaging techniques to investigate whether long COVID patients with persistent symptoms show signs of brain inflammation.<\/p>\n \u201cWe did not observe evidence of widespread brain inflammation in patients with long COVID when compared to healthy controls,\u201d says Professor of Neuroimmunology and InFLAMES Research Flagship group leader Laura Airas, who led the study.<\/p>\n The study included 14 individuals with long COVID, 11 healthy controls, and 13 patients with multiple sclerosis (MS), a neurological disease known to involve brain inflammation.<\/p>\n All participants underwent PET imaging sensitive to neuroinflammation, along with magnetic resonance imaging (MRI) to assess brain structure and white matter changes. Blood samples were analysed for biomarkers reflecting neuronal and glial damage.<\/p>\n Compared to MS patients, individuals with long COVID showed significantly lower inflammatory activity in the brain\u2019s white matter. No differences in markers of brain inflammation or neurodegeneration were observed between long COVID patients and healthy controls.<\/p>\n Clear signs of brain inflammation have previously been observed in neuropathological studies of severe acute COVID-19. In the current study, individuals scanned within 16 months of infection showed higher white matter inflammatory activity compared to those with longer disease duration.<\/p>\n According to Airas, this suggests that inflammation may be more prominent during the early phase of the disease and decrease over time.<\/p>\n An important finding of the study was that higher levels of depression and anxiety, as well as lower quality of life, were associated with increased cellular activity in the hippocampus and amygdala. They are brain regions involved in memory, emotional regulation, and stress responses.<\/p>\n These findings suggest that altered cellular activation in emotion-regulating brain regions may be linked to symptom severity in some patients with long COVID.<\/p>\n The researchers note that the findings refine our understanding of long COVID and challenge the idea that persistent brain inflammation is the primary driver of prolonged symptoms in all patients. Instead, the results point to a more complex disease profile, where inflammatory changes may be strongest right after infection and diminish over time.<\/p>\n Long COVID is a recognised condition affecting millions of people worldwide, with symptoms that can persist for months or even years after the initial infection.<\/p>\n The researchers suggest that patients with prolonged symptoms may benefit more from treatments targeting stress and emotional regulation rather than therapies aimed solely at reducing inflammation.<\/p>\n \u201cThis study highlights the need to continue investigating the complex biological mechanisms underlying long COVID. Understanding these processes is essential for developing targeted treatments,\u201d notes Airas.<\/p>\n The study by Airas and colleagues has been published in the\u00a0Journal of Neurology<\/em>.<\/p>\n A<\/strong>: The study reveals that your symptoms are completely real, but the biological engine behind them changes over time. While widespread inflammation appears to peak during the early months after infection, long-term symptoms are tied to altered cellular activity in specific emotion and stress-processing hubs, the hippocampus and the amygdala.<\/p>\n<\/div>\n A<\/strong>: Multiple sclerosis is a neurological disease known for definitive, aggressive brain inflammation. By scanning Long COVID patients alongside MS patients and healthy individuals, the team created a clear benchmark. The scans revealed that the white matter in Long COVID brains had significantly less inflammation than MS brains, matching the baseline of healthy controls.<\/p>\n<\/div>\n A<\/strong>: The data suggests that anti-inflammatory treatments might only be highly effective during the initial phase of the disease, particularly within the first 16 months post-infection. For patients dealing with prolonged, multi-year symptoms, the brain\u2019s inflammatory response has already quieted down, meaning therapies targeting stress paths and emotional regulation will offer much better relief.<\/p>\n<\/div>\n<\/div>\n Author:\u00a0<\/strong>Tuomas Koivula<\/a>\n
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<\/picture>Brain inflammation may be present early after infection<\/strong><\/h2>\n
Toward a clearer understanding of long COVID and targeted treatments<\/strong><\/h2>\n
Key Questions Answered:<\/h3>\n
Editorial Notes:<\/h3>\n
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About this Long-COVID and neurology research news<\/h2>\n
Source:\u00a0<\/strong>University of Turku<\/a>
Contact:\u00a0<\/strong>Tuomas Koivula \u2013 University of Turku
Image:\u00a0<\/strong>The image is credited to Neuroscience News<\/p>\n