SARS-CoV-2 may alter brain structures
aks/aerzteblatt.de
Oxford - A reduction in gray matter in certain brain regions is a possible consequence of infection with SARS-CoV-2, and the limbic system seems to be particularly affected. This is indicated by recent study results published in Nature (2022, DOI: 10.1038/s41586-022-04569-5) by a research group led by Gwenaëlle Douaud from the Nuffield Department of Clinical Neurosciences (NDCN) at the University of Oxford.
It is known from various studies that COVID-19 can be associated with changes in the brain. To date, however, little is known about whether mild SARS-CoV-2 infections also affect the brain and what mechanisms might contribute to the pathological processes in the brain.
The researchers now examined brain scans obtained by magnetic resonance imaging (MRI) from 785 individuals from the UK Biobank who were between 51 and 81 years of age. Two brain scans were available from all participants. An average of 3 years elapsed between the 2 scans. SARS-CoV-2 infection had been detected in 401 individuals. The other 384 individuals formed the control group matched for age, sex, ethnicity, and time between scans.
For the SARS-CoV-2-positive participants, the first admission occurred before infection and the second after. There was an average of 141 days between diagnosis and the second admission. The authors found significant differences between the two groups.
For example, those infected with SARS-CoV-2 showed greater reductions in gray matter and tissue contrast in the orbitofrontal cortex and parahippocampal gyrus. The differences were moderate on average and ranged from 0.2 to 2%.
Furthermore, evidence for tissue damage could be found in the individuals with SARS-CoV-2 infection. The changes occurred in regions functionally associated with the primary olfactory cortex.
Participants with SARS-CoV-2 infection also had greater brain size reduction. They also had greater mean cognitive decline between the two admission time points.
Among the 401 people with SARS-CoV-2 infection, there were 15 who required hospitalization. The authors performed another analysis from which they removed these 15 participants: The changes in imaging and cognition could still be detected.
It is possible that the aforementioned changes, which occur primarily in the limbic system, represent hallmarks of disease propagation via olfactory signaling pathways, the authors reason. They could also represent neuroinflammatory events or the loss of sensory input caused by anosmia.
Whether the changes can be at least partially reversed or persist in the long term should be evaluated in further studies, the authors added."
Translated with www.DeepL.com/Translator (free version)
SARS-CoV-2 is associated with changes in brain structure in UK Biobank
https://www.nature.com/articles/s41586-022-04569-5
WUM
Translated with www.DeepL.com/Translator (free version)
aks/aerzteblatt.de
Oxford - A reduction in gray matter in certain brain regions is a possible consequence of infection with SARS-CoV-2, and the limbic system seems to be particularly affected. This is indicated by recent study results published in Nature (2022, DOI: 10.1038/s41586-022-04569-5) by a research group led by Gwenaëlle Douaud from the Nuffield Department of Clinical Neurosciences (NDCN) at the University of Oxford.
It is known from various studies that COVID-19 can be associated with changes in the brain. To date, however, little is known about whether mild SARS-CoV-2 infections also affect the brain and what mechanisms might contribute to the pathological processes in the brain.
The researchers now examined brain scans obtained by magnetic resonance imaging (MRI) from 785 individuals from the UK Biobank who were between 51 and 81 years of age. Two brain scans were available from all participants. An average of 3 years elapsed between the 2 scans. SARS-CoV-2 infection had been detected in 401 individuals. The other 384 individuals formed the control group matched for age, sex, ethnicity, and time between scans.
For the SARS-CoV-2-positive participants, the first admission occurred before infection and the second after. There was an average of 141 days between diagnosis and the second admission. The authors found significant differences between the two groups.
For example, those infected with SARS-CoV-2 showed greater reductions in gray matter and tissue contrast in the orbitofrontal cortex and parahippocampal gyrus. The differences were moderate on average and ranged from 0.2 to 2%.
Furthermore, evidence for tissue damage could be found in the individuals with SARS-CoV-2 infection. The changes occurred in regions functionally associated with the primary olfactory cortex.
Participants with SARS-CoV-2 infection also had greater brain size reduction. They also had greater mean cognitive decline between the two admission time points.
Among the 401 people with SARS-CoV-2 infection, there were 15 who required hospitalization. The authors performed another analysis from which they removed these 15 participants: The changes in imaging and cognition could still be detected.
It is possible that the aforementioned changes, which occur primarily in the limbic system, represent hallmarks of disease propagation via olfactory signaling pathways, the authors reason. They could also represent neuroinflammatory events or the loss of sensory input caused by anosmia.
Whether the changes can be at least partially reversed or persist in the long term should be evaluated in further studies, the authors added."
Translated with www.DeepL.com/Translator (free version)
SARS-CoV-2 is associated with changes in brain structure in UK Biobank
https://www.nature.com/articles/s41586-022-04569-5
WUM
Translated with www.DeepL.com/Translator (free version)
4
