Covid-19: Mild cases may have accelerated brain aging
According to a new study, people who have contracted Covid-19 even in a mild form may have accelerated the aging of the brain and other changes. This study is believed to be the largest of its kind; the researchers found that the brains of those who had Covid-19 had increased loss of gray matter and abnormalities in brain tissue.
Many of these changes were in the area of the brain related to smell. Researchers were also surprised to see these effects on a brain affected by such a mild form. The researchers analyzed the brain imaging of 401 people who had Covid-19 between March 2020 and April 2021, both before infection and on average 4 and a half months after infection. They compared the results with brain imaging of 384 uninfected people who were similar in age, socioeconomics, and risk factors such as blood pressure and obesity.
Covid-19, the mild form can lead to brain aging
Study participants ranged in age from 51 to 81, and all were part of a health database opened in 2012. Experts suggested that It is common for people to lose 0.2 to 0.3% of their gray matter every year, in the brain area of memory as they age. However from the study evaluation, the people infected with the virus further lost 0.2 to 2% gray matter. In addition to this analysis, the participants were tested on their cognitive and executive functions, to detect cognitive disturbances associated with dementia and to test the speed and processing function of a person’s brain.
Thanks to this test, the researchers found that those who lost the most brain tissue did badly on this test. Although the most affected areas of the brain appear to be related to the olfactory system, the team said that it was not clear why this was so. Since the abnormal changes could be partly related to their loss of smell, it is possible that recovery could lead to these less marked brain abnormalities over time. Likewise, the harmful effects of the virus are likely to lessen over time after infection. The best way to find out would be scan these participants again in a year or two and see if there are still traces of the virus.
Loss of smell is related to the loss of gray matter
Although this correlation between Covid-19 and brain function has been found, it is still not entirely clear why. Previous studies have shown that people with significant and repeated loss of smell they also have an associated loss of gray matter. However, this study did not assess whether people actually had a loss of smell. However it was possible to note that the long-term consequences of the virus may over time contribute to Alzheimer’s disease and other forms of dementia. It is really difficult to know the long-term clinical impact and impact on quality of life in a situation like this.
The brain can be affected by other mechanisms such as immune, inflammatory, vascular or psychological change, but not direct infection. What this study almost certainly shows is the impact, in terms of neural changes. However it doesn’t help us understand the mechanisms underlying cognitive change after Covid-19 infection.
Image by Pete Linforth from Pixabay