A recent British study found that people who suffered severe cases of COVID-19 to the extent they received critical care experienced cognitive impacts equivalent to about 20 years of aging or a loss of 10 IQ points.
The study was conducted by researchers from the University of Cambridge and Imperial College London and involved 46 patients receiving critical care for COVID-19 at a Cambridge hospital between March and June 2020.
Study participants took part in a “personalized computerized cognitive assessment battery” in which they completed eight tasks using an iPad. On average, participants participated in these evaluations around 179 days, almost six months, after the onset of COVID-19.
“Participants who had been hospitalized due to COVID-19 scored significantly lower and were slower in their responses than would be expected given the control population,” the study reads.
According to the researchers, the participants showed a “consistent pattern of poor cognitive performance” in terms of accuracy and processing time when completing assigned tasks. They noted that the cognitive impact appeared to be stronger in patients requiring mechanical ventilation.
The researchers compared the observed impact to the normal cognitive decline that people experience during the 20 years of aging between ages 50 and 70. However, improvement in cognitive test scores and reaction times was seen in study participants, although recovery was described as “gradual at best.”
“Tens of thousands of people have been through intensive care with COVID-19 in England alone and many more will have been very ill, but not admitted to hospital,” said Adam Hampshire, study author and professor in the Department of Brain Sciences. at Imperial College London.
“This means that there are a large number of people who are still experiencing cognitive problems many months later. We urgently need to see what can be done to help these people,” said Hampshire.
One limitation of the study that the researchers acknowledged was that it relied on self-report of cognitive deficits rather than objective assessments. They also acknowledged that conditions such as depression, anxiety, fatigue, and post-traumatic stress following a COVID-19 infection may have contributed to the observed cognitive impacts.
The aging effects of the COVID-19 pandemic in general have been previously noted by health experts. Factors such as serious illness, chronic stress, and loneliness are known to contribute to accelerated aging.
Another study published last month from China found that COVID-19 infection could contribute to accelerated aging in patients, although the researchers noted that these effects were reversible in some patients.