Covid increases risk of ‘mental fog’ and other brain disorders, study indicates

Diagnoses of dementia, epilepsy and “mental fog” are more common two years after having Covid-19 than with other respiratory infections, according to a study from the University of Oxford in the United Kingdom.

Other conditions, however, such as anxiety and depression did not become more frequent in those who were infected with the coronavirus between 2020 and 2021, according to the research.

More work is needed to understand how and why Covid can lead to other conditions that affect the brain and well-being.

Broadly speaking, experts say the virus has disrupted routine and life, as well as making people sick.

Previous research has shown that adults are at a higher risk of brain and mental illness within six months of coming into contact with the coronavirus.

The most recent study looked at the risk of suffering from 14 different disorders in 1.25 million patients who had covid two years ago.

This group was then compared with another, also of 1.25 million people, who were diagnosed with other respiratory infections (such as the flu or cold, for example).

In the group that had covid two years ago, it was possible to observe more cases of:

• Dementia, stroke and mental confusion in adults over 65 years of age;
• “Mental fog” in adults aged 18 to 64 years. This is a generic term that scientists use to describe frames of confusion and forgetfulness, as if reasoning and memory are scrambled;
• Epilepsy and psychotic disorders in children, although the risks were small.

Children’s risk of developing epilepsy after having covid was 260 per 10 thousand people, for example. In those affected by other respiratory infections, this rate stood at 130 out of 10,000.

The probability of developing a psychotic disorder also increased after the illness – it was 18 in 10,000 – but it is still considered a rare condition by experts.

The study also revealed that some disorders became less common two years after infection, such as:

• Anxiety and depression in children and adults;
• Psychotic disorders in adults.

According to the survey, the increased risk of depression and anxiety in adults in the post-covid period lasts for less than two months before returning to levels considered normal.

‘Worrisome’

Professor Paul Harrison, lead author of the study, considers it “worrying” that some disorders, such as dementia and seizures, become more frequent post-covid, even two years after a positive diagnosis.

But the specialist, who integrates the department of psychiatry at the University of Oxford, classifies as “good news” the fact that cases of depression and anxiety have a “short life” and are not observed in children.

The researchers indicate that the numbers of affected individuals were “hard to ignore” but “did not form a tsunami”. Some of them, however, need medical attention, which could further increase the pressure on health services.

The study, published in the journal The Lancet Psychiatry, did not track each participant over that period—instead, it compiled and compared the number of people with a new diagnosis of the disorder in the two years that elapsed after infection.

The article also did not look at the severity of each condition after diagnosis or how long it lasted, and whether the post-covid illnesses described are similar to those that occur in other infections.

Scientists also chose not to call these conditions “long covid,” although mental fog — or problems with memory and concentration — is a typical symptom.

The omicron variant, which has caused record new cases over the past few months, is linked to a lower likelihood of suffering from long-term symptoms compared to previous strains of the coronavirus, recent research suggests.

However, although it causes a less severe acute condition than the delta variant, the omicron appears to carry similar risks of brain and mental diseases, according to the study from the University of Oxford.

‘Social unrest’

The just-published study has some limitations — it didn’t look, for example, at how Covid can cause brain and mental disorders, although some experts say this could be explained by the development of tiny blood clots.

Professors Jonathan Rogers and Glyn Lewis of University College London, also in the UK, who were not involved in the research, said the study highlighted “some clinical features that warrant further investigation”, but added that more work was needed to confirm the findings.

Professor David Menon, from the University of Cambridge (United Kingdom), calculates that the impact of being in hospital with covid is comparable to “20 years of aging”.

Paul Garner, professor emeritus at the Liverpool School of Tropical Medicine (UK), points out that the pandemic has changed people’s lives in many ways.

He notes that the small increases seen in conditions such as dementia and psychosis may be more related “to the social unrest and dystopia we live in, rather than being a direct effect of the virus”.

– This text was originally published at https://www.bbc.com/portuguese/geral-62589473