One in eight people who have recovered from COVID-19 are diagnosed with their first psychiatric or neurological illness within six months of testing positive for the bug, according to a new study.
Researchers who surveyed 236,379 coronavirus survivors found that the numbers rose to one in three when people with a previous history of psychiatric or neurological illnesses were included, the Guardian reported.
In addition, the study found that one in nine patients also were diagnosed with conditions such as depression or stroke despite not having gone to a hospital when they were infected, according to lead author Dr. Max Taquet of the Department of Psychiatry at the University of Oxford.
The study, which has not yet been peer-reviewed, used electronic health records to evaluate hospitalized and non-hospitalized US patients with a confirmed COVID-19 diagnosis who recovered.
The subjects were compared with a group diagnosed with influenza, and another diagnosed with respiratory tract infections between Jan. 20 and Dec. 13, 2020, according to the news outlet.
Their analysis accounted for factors such as age, race, gender, socioeconomic status and any underlying physical and mental conditions.
According to the results, the likelihood of a COVID-19 survivor developing a psychiatric or neurological illness within six months was 33.6 percent; almost 13 percent of the survivors did, in fact, receive a diagnosis in that time frame, the study found.
The researchers also discovered that most diagnoses were more common after bouts with the coronavirus than after the flu or other respiratory infections — including stroke, intracranial bleeding, dementia and psychotic disorders.
Overall, COVID-19 was linked to increased risk of these diagnoses, but the incidence was greater among those who required hospital treatment, and significantly so among patients who developed brain disease, the Guardian reported.
When asked how long these conditions might last after diagnosis, Taquet told the outlet, “I don’t think we have an answer to that question yet.”
He added: “For diagnoses like a stroke or an intracranial bleed, the risk does tend to decrease quite dramatically within six months … but for a few neurological and psychiatric diagnoses, we don’t have the answer about when it’s going to stop.”
Although the study does not prove that COVID-19 is directly behind the psychiatric and neurological conditions, research suggests the bug can have an impact on the brain and the central nervous system.
Dr. Tim Nicholson, a psychiatrist and clinical lecturer at King’s College hospital who was not involved in the study, said the results would help researchers decide which neurological and psychiatric complications required further careful study.
“I think particularly this raises a few disorders up the list of interests, particularly dementia and psychosis…and pushes a few a bit further down the list of potential importance, including Guillain-Barré syndrome,” he told the Guardian.
Meanwhile, another study has found that the coronavirus may remain inside the brain of severely ill patients and trigger relapses among those who thought they had recovered.
Researchers at Georgia State University discovered that infecting the nasal passages of mice with the virus led to a rapid, escalating attack on the brain that triggered severe illness.
Assistant professor Mukesh Kumar, the lead researcher, said the findings have implications for understanding the wide range of symptoms and severity of illness among people who contract the illness.
“Our thinking that it’s more of a respiratory disease is not necessarily true,” Kumar said.
“Once it infects the brain, it can affect anything because the brain is controlling your lungs, the heart, everything. The brain is a very sensitive organ. It’s the central processor for everything.”
That study has been published in the journal Viruses.