Study: Severe COVID causes cognitive loss equivalent to 20 years of ageing

A new study has found that patients who recover from severe COVID suffer the same cognitive impairment that people go through between the ages of 50 and 70.

According to the researchers from the University of Cambridge and Imperial College London, this is the equivalent of losing 10 IQ points.

In the study, the researchers analysed data from 46 individuals who received critical care for COVID between March 10, 2020, and July 31, 2020 at Addenbrooke’s Hospital in Cambridge, England.

Among the patients, 16 were said to have been placed on mechanical ventilation during their stay in hospital.

The individuals reportedly underwent detailed computerised cognitive tests for an average of six months after their severe illness using the “Cognitron platform”, which measures different aspects of mental faculties such as memory, attention and reasoning.

Scales measuring anxiety, depression and post-traumatic stress disorder were also said to have been assessed and the data compared against matched controls.

The researchers said the COVID survivors were less accurate and had slower response times than the matched control population.

They added that these deficits were still detectable when the patients were following up six months later and that the effects were strongest for those who required mechanical ventilation.

“By comparing the patients to 66,008 members of the general public, the researchers estimate that the magnitude of cognitive loss is similar on average to that sustained with 20 years ageing, between 50 and 70 years of age, and that this is equivalent to losing 10 IQ points,” the researchers said.

David Menon, the study’s senior author, said: “Cognitive impairment is common to a wide range of neurological disorders, including dementia, and even routine ageing, but the patterns we saw – the cognitive ‘fingerprint’ of COVID-19 – was distinct from all of these.”