Long Covid may lower your IQ by up to SIX points, major study warns

Long Covid may cause sufferers’ IQ to drop by six points, a major study suggests.

Researchers in the UK found the loss for patients who said they had been suffering from Covid symptoms for more than 12 weeks compared to those who said they had never had the virus.

They also calculated a loss of three IQ points among those who said they had Covid symptoms for up to 12 weeks, and of nine IQ points for those who were admitted to the ICU during their infection compared to those who said they were not infected.

Experts suggested long-term virus symptoms could indicate someone has high levels of inflammation, which can damage the brain by causing stress to brain cells.

The researchers said: ‘Our results confirmed associations of cognitive deficits with mood swings and fatigue but also with a variety of other symptoms. 

‘Therefore, it is likely that multiple underlying factors contribute to cognitive deficits after Covid.’

Long Covid is a poorly-defined illness which is notoriously difficult to diagnose, with some doctors even saying it does not exist.

Patients who have the syndrome complain of a wide variety of symptoms including persistent fatigue, brain fog and inability to carry on with life as normal. 

The study — published in the New England Journal of Medicine —  calculated a ‘global cognition score’ for participants, which was then used to generate an IQ score.

The average person in the US has an IQ of about 98, estimates suggest — with males having a slightly higher score than females.

This suggests that people who say they have Long Covid may have an IQ score of about 93 points — while those who previously had Covid could have an IQ around 95 points.

An IQ score is a numerical measure of a person’s intelligence based on a battery of reasoning, problem-solving, memory and linguistic tests.

But it has limitations, including that it struggles to capture other areas of intelligence such as creativity and emotional intelligence and that people who perform it regularly become more familiar with the test, resulting in a higher score.

For the study, scientists sent out a request to complete eight cognitive tests to a random group of more than 800,000 people registered with the UK’s National Health Service (NHS).

More than 110,000 replied, including more than 3,000 people who said their Covid symptoms had persisted for longer than 12 weeks — which the researchers defined as ‘Long Covid’.

The majority of participants were women in their 50s and 60s and from a white ethnic background. 

Most were also infected while Omicron was the dominant variant and nearly 1,500 had been hospitalized with the virus. A total of 300 participants said they had been admitted to the ICU.

They completed eight tests to measure mental abilities including memory, spatial working memory and verbal reasoning among others.

Other results included that participants who reported having Covid early were more likely to have cognitive decline compared to those in other groups. 

Limitations of the study included that it had no data on people’s cognitive ability before they caught Covid, meaning comparisons were not possible.