Long Covid may lower a person’s IQ by up to six points: study

Health

By Alex Mitchell

Long COVID can reduce a person’s IQ by up to six points, worrying research has revealed.

A report in the New England Journal of Medicine found that COVID-19 was “associated with longer-term objectively measurable cognitive deficits.” Experts were attempting to learn more about the mentally straining phenomenon commonly referred to as brain fog, brought on by the virus.

Those who had symptoms for around 12 weeks saw the largest IQ reduction.

Unrelated research found that nearly a quarter of American Covid-19 patients experienced symptoms lasting three months or more.

“It’s not been at all clear what brain fog actually is,” author Adam Hampshire of Imperial College London told The Guardian.

“As a symptom, it’s been reported on quite extensively, but what our study shows is that brain fog can correlate with objectively measurable deficits. That is quite an important finding.”

In assessments of over 141,000 people, tests were run regarding immediate memory, two-dimensional mental manipulation, spatial working memory, spatial planning, verbal analogical reasoning, word definitions, information sampling, and delayed memory.

“The memory, reasoning, and executive function (i.e., planning) tasks were among the most sensitive to Covid-19–related cognitive differences,” the authors wrote.

The study also suggests that earlier cases of the original virus or alpha variant near the start of the pandemic carried the largest waves of cognitive decline.

It was also reported that there was “a small cognitive advantage” for participants who were given two or more vaccinations for Covid-19 and saw minimal effects from repeat episodes of the illness.

Although only 3.5% of patients in the Imperial College study showed symptoms for 12 weeks or longer, experts emphasized that this number is more concerning than it seems.

“Even if cognitive deficits after Covid-19 are of small magnitude on average, a substantial minority of people have more significant deficits which are likely to affect their ability to work and function,” psychiatrist Dr. Maxime Taquet of Oxford University told the outlet.

“Given the scale of the pandemic and the number of people affected, this is particularly worrisome.”