Lasting brain impacts of severe COVID-19 equivalent to 20 years of ageing (or a loss of 10 IQ points)

Research Institutions: University of Cambridge and Imperial College London
Publication: eClinicalMedicine journal
Lead Author: Professor Adam Hampshire, Department of Brain Sciences, Imperial College London
Senior Author: Professor David Menon, Division of Anaesthesia, University of Cambridge

Cognitive Impairment: Severe ==COVID-19 can cause cognitive impairment equivalent to a 20-year ageing process, or a loss of 10 IQ points.
Recovery: Any recovery is gradual and the effects are detectable more than six months after acute illness.
First of its Kind: This study is the first rigorous assessment and comparison carried out in relation to the after-effects of severe COVID-19.

Participants: 46 people who received in-hospital care for COVID-19, including 16 who were put on mechanical ventilation.
Test Platform: Cognitron platform, which measures different aspects of mental faculties such as memory, attention, and reasoning.
Comparison Group: The data of the participants were compared against matched controls and 66,008 members of the general public.

Symptoms: Recovered patients report lasting cognitive and mental health problems including 'brain fog', sleep disturbances, and anxiety.
UK Statistics: About one in seven individuals in the UK reported having cognitive difficulties 12 weeks after a positive COVID-19 test.
Hospitalized Patients: Between a third and three-quarters of hospitalized patients reported suffering cognitive symptoms three to six months later.

Response Times: COVID-19 survivors were less accurate and had slower response times compared to the control population.
Verbal Analogical Reasoning: Survivors scored poorly in tasks such as verbal analogical reasoning, aligning with the commonly reported problem of difficulty finding words.
Processing Speeds: They also showed slower processing speeds, which is linked to decreased brain glucose consumption in the frontoparietal network of the brain. Also know as Brain Hypometabolism

Mental Health Symptoms: Recovered individuals can experience a range of mental health symptoms including depression, anxiety, and post-traumatic stress.
Recovery Prospects: While there was a very slow improvement observed in some patients up to ten months after acute infection, it is possible that some individuals may never fully recover.
Causes of Cognitive Deficits: The cognitive deficits could be caused by a combination of factors including inadequate oxygen or blood supply to the brain, clotting, microscopic bleeds, and damage caused by the body’s inflammatory response and immune system.

Call to Action: There is an urgent need to find ways to help the large number of people experiencing cognitive problems many months after recovering from COVID-19. Also known as Long COVID
Funding: The research was funded by the NIHR BioResource, NIHR Cambridge Biomedical Research Centre, and the Addenbrooke’s Charitable Trust.

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