One in three people who have suffered from Covid-19 was diagnosed with a neurological or psychiatric condition within six months of infection, according to scientists who have carried out the largest study of the mental health effects of coronavirus. They found that Covid-19 was 44 per cent more likely to cause neurological and mental problems than a case of influenza of comparable severity.
“Although the individual risks for most disorders are small, the effect across the whole population may be substantial for health and social care systems due to the scale of the pandemic and the fact that many of these conditions are chronic,” said Paul Harrison, professor of psychiatry at Oxford university and the project leader. “
As a result, healthcare systems need to be resourced to deal with the anticipated need, both within primary and secondary care,” he added. Researchers at Oxford compared the health records of 236,400 Covid-19 patients and 105,600 people who were diagnosed with influenza over the same period, from January to December 2020. The groups were matched as far as possible for the severity of disease.
The study was published Tuesday night in The Lancet Psychiatry. Data for the study came from TriNetX, a US organisation that gathers anonymised health records from 81m patients in hospitals and primary care. Anxiety, at 17 per cent, and mood disorders, 14 per cent, were the most common mental diagnoses following Covid-19, the study showed. These proportions were about 45 per cent higher than in the matched flu patients. “Neurological diagnoses such as stroke and dementia were rarer but not uncommon in those who had been seriously ill,” the researchers reported. “For example, of those who had been admitted to intensive care, 7 per cent had a stroke and almost 2 per cent were diagnosed with dementia.”
Covid-19 patients were more than twice as likely as those with flu to develop dementia, 2.5 times more likely to suffer a brain haemorrhage and 60 per cent more likely to have a stroke. “Our results indicate that brain diseases and psychiatric disorders are more common after Covid-19 than after flu or other respiratory infections, even when patients are matched for other risk factors,” said Max Taquet, a co-author of the study. “We now need to see what happens beyond six months.”
Professor Til Wykes of the Institute of Psychiatry at King’s College London, who was not involved in the research, commented: “Looking over six months after diagnosis has demonstrated that the ‘after effects’ can appear much later than expected — something that is no surprise to those suffering from long Covid.” “There is little good news from these data except that the anxiety and depression rates were decreasing compared to data collected three months after diagnosis,” she said, “but this is balanced by the increase in more serious psychotic illnesses.”