When an unexpected radical virus sweeps the world, we have to prepare for unforeseen consequences. And, sadly, it seems COVID-19 survivors may suffer from a loss of gray matter and other brain tissue, as a long-term effect of the virus, according to a recent study shared on a preprint server.
COVID-19 Infection Could Lead to Loss of Gray Matter
Scientists have found a strong correlation between people who contracted and survived COVID-19, and brain related pathologies. This came as a result of a long-term experiment that involved 782 volunteers, compared brain scans of individuals before the pandemic.
For an analogy between pre-pandemic and post-pandemic brain scans, researchers then invited 394 COVID-19 survivors to return for follow-up scans, as well as 388 healthy volunteers.
Among those participants who recovered from COVID-19, researchers saw significant effects of the virus on the human cerebral matter, with a loss of gray matter in regions of the brain. It should be noted that the study has yet to undergo rigorous peer review.
“Our findings thus consistently relate to the loss of gray matter in limbic cortical areas directly linked to the primary olfactory and gustatory system,” which are the regions of the brain responsible for our sense of smell and taste, wrote the authors in the preprint study.
Gray matter of our brains is crucial to the nervous system, operating the myriad functions of the brain. This part of the brain allows us to determine memory, emotions, and movement, which means any abnormality could alter brain cells and reduce communication skills.
The study also found that when humans lose gray matter in areas of the brain linked with memory, it could “increase the risk of these patients of developing dementia in the longer term,” wrote the authors.
While several breakthrough studies have recently surfaced about dementia and Alzheimer’s treatment, including a new drug to treat symptoms of dementia, the drug is still controversial among experts, and other studies mostly happened in experiments with mice, and so are perhaps too preliminary to offer realistic hope of treating existing and future victims of such neurological degeneration.
Most of the COVID-19 survivors involved in the research experienced mild-to-moderate symptoms or had none at all. This was viewed as a strength of the analysis, as most brain-imaging publications have focused on moderate-to-severe cases of COVID-19.
“There is a fundamental need for more information on the cerebral effects of the disease even in its mildest form,” the Biobank study read.
Long Term Effects of COVID-19 Infection
And this finding, which again is still in need of peer review, comes on the heels of another study published in the journal Lancet Psychiatry in 2020, which suggested COVID-19 infections could leave significant damage in the brain, leading to long-term complications like dementia, or stroke-like issues.
But like the recent one, the authors of the 2020 study emphasized a need for additional data and review before we have a crystal-clear picture of how a serious COVID-19 case ultimately affects brain health. Most volunteers in the recent study who had survived COVID-19 suffered mild-to-moderate symptoms or none at all.
This was a unique contribution of the study since many earlier studies honed in on only severe cases of the illness. “There is a fundamental need for more information on the cerebral effects of the disease even in its mildest form,” read the preprint study.
It is important to note, there were no changes in brain matter observed in study participants who weren’t infected by COVID-19 coronavirus. The authors of the study said more research is needed to determine whether COVID-19 survivors will have issues in the long term regarding their ability to remember emotion-evoking events.
They also cannot confirm whether the loss of gray matter is a result of the virus spreading into the brain or some other effect of the illness.
- Brain imaging before and after COVID-19 in UK Biobank. Gwenaëlle Douaud, Soojin Lee, Fidel Alfaro-Almagro, Christoph Arthofer, Chaoyue Wang, Frederik Lange, Jesper L.R. Andersson, Ludovica Griffanti, Eugene Duff, Saad Jbabdi, Bernd Taschler, Anderson Winkler, Thomas E. Nichols, Rory Collins, Paul M. Matthews, Naomi Allen, Karla L. Miller, Stephen M. Smith. DOI: https://doi.org/10.1101/2021.06.11.21258690
- 6-month neurological and psychiatric outcomes in 236 379 survivors of COVID-19: a retrospective cohort study using electronic health records. Maxime Taquet, PhD, Prof John R Geddes, MD, Prof Masud Husain, FRCP, Sierra Luciano, BA. Prof Paul J Harrison, FRCPsych. Lancet psychiatry. Articles| volume 8, ıssue 5, p416-427, May 01, 2021. Open AccessPublished: April 06, 2021. DOI:https://doi.org/10.1016/S2215-0366(21)00084-5