New data published in one of the pinnacle science journals, Nature, suggests that even mild cases of COVID can lead to unexpectedly large decreases in brain mass, some as large as the equivalent of ten years of aging.
Evaluating “785 UK Biobank participants (aged 51–81) imaged twice, including 401 cases who tested positive for infection withSARS-CoV-2 between their two scans,” it finds surprising brain abnormalities between many cases. Such changes included reduced gray matter thickness, increased markers indicating damage, and reduced overall brain mass.
What’s more, “infected participants also showed on average larger cognitive decline between the two timepoints. Importantly, these imaging and cognitive longitudinal effects were still seen after excluding the 15 cases
who had been hospitalised,” meaning that this applies to average cases, not simply severe ones.
Such changes were suggestive that even mild COVID can precipitate a brain mass decrease of between 0.2 and as much as 2 percent over a period of less than six months, equivalent to 1-10 years of brain aging, along with the mental declines associated with such decreases.
The “significantly greater cognitive decline, which persisted even after excluding the hospitalised patients,” especially on the massive global scale of which COVID-19 has infected nearly half a billion people, has the potential to materially damage global intelligence of the human species in lasting ways with unforeseen generational consequences.
Source: Douaud, G. et al. SARS-CoV-2 is associated with changes in brain structure in UK Biobank. Nature https://doi.org/10.1038/s41586-022-04569-5 (2022).