Patients who experience severe COVID could suffer mental impairment equivalent to losing 10 IQ points, according to a new study conducted by researchers at the University of Cambridge and Imperial College London.
The study examined 46 patients six to 10 months after they were hospitalized with the virus, and showed a marked decrease in their intellectual capabilities. For patients whose cases resulted in being on ventilators and other organ support devices, the researchers estimated their mental acuity dropped as if they had aged 20 years in just a few months.
“Cognitive impairment is common to a wide range of neurological disorders, including dementia, and even routine [aging], but the patterns we saw—the cognitive ‘fingerprint’ of COVID-19—[were] distinct from all of these,” said David Menon, a professor at the University of Cambridge and the study’s senior author, in a statement.
As many as one-third to three-quarters of hospitalized patients reported still suffering cognitive symptoms three to six months after their release.
In the U.K., approximately 40,000 people entered intensive care with COVID symptoms. That number is undoubtedly significantly higher in the U.S., which raises the possibility of a wide swath of people experiencing problems with cognition months after recovering from the virus.
The good news, although it’s muted, is that some patients showed slight recovery after almost a year, but it was gradual at best.
“We followed some patients up as late as 10 months after their acute infection, so were able to see a very slow improvement,” said Menon. “While this was not statistically significant, it is at least heading in the right direction, but it is very possible that some of these individuals will never fully recover.”
Among the most common issues patients faced were difficulty finding words and slower processing speeds.
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