Long Covid ‘brain fog’ comparable to ageing 10 years, study finds
Posted on the 26th July 2023
The ‘brain fog’ symptom associated with long Covid is comparable to ageing 10 years, a new study has revealed.
Researchers at King’s College London studying the impact of Covid-19 on memory found cognitive impairment highest in individuals who had tested positive and had more than three months of symptoms.
The findings, published in The Lancet, also show the affected individuals’ symptoms stretch to almost two years since their initial infection.
The study included more than 5,100 participants from the Covid Symptom Study Biobank, recruited through a smartphone app.
Through 12 cognitive tests measuring speed and accuracy, researchers examined working memory, attention, reasoning, and motor controls between two periods of 2021 and 2022.
In the first cohort of 3,335 participants during July and August 2021, researchers found lower cognitive scores in individuals with positive Covid-19 infections, with the largest deficits seen in those with more than 12 weeks of symptoms.
An estimated two million people living in the UK were experiencing self-reported long Covid – symptoms continuing for more than four weeks since infection – as of January 2023, according to the 2023 government census.
Commonly reported symptoms included fatigue, difficulty concentrating, shortness of breath and muscle aches.
The study said the deficits were comparable to the effect of “an increase in age of approximately 10 years, or exhibiting mild or moderate symptoms of psychological distress”.
However, this was smaller than other effects, such as lower educational attainment or above-threshold fatigue levels, the study said.
Researchers found no significant improvement scores in the second round of 1,786 participants in April and June of 2022, nine months after the first.