Scientists have developed a detailed snapshot of the neurological complications in Covid-19 patients, an advance that may help establish the mechanisms of these symptoms and lead to the development of potential treatments for the deadly disease.
The researchers, including those from The University of Liverpool in the UK, assessed 153 patients hospitalised during the acute phase of the pandemic and found that the most common brain complication observed was stroke.
They described the range of neurological and psychiatric complications that may be linked to the disease in the study published in the journal The Lancet Psychiatry.
"There have been growing reports of an association between Covid-19 infection and possible neurological or psychiatric complications, but until now these have typically been limited to studies of ten patients or fewer," said Benedict Michael, lead-author of the study from The University of Liverpool.
In the study, the scientists set up a secure, UK-wide digital network for specialist doctors to report details of specific cases. They said these portals were hosted by professional bodies representing specialists in neurology, stroke, psychiatry, and intensive care.
"This data represents an important snapshot of the brain-related complications of Covid-19 in hospitalised patients. It is critically important that we continue to collect this information to really understand this virus fully," said Sarah Pett, co-author of the study from the University College London in the UK.
According to Pett, similar studies conducted on a larger scale can help understand the "frequency of these brain complications, who's most at risk of getting them, and ultimately how best to treat."
The scientists said the most common brain complication observed was stroke, which was reported in 77 of 125 patients. Of these, they said 57 patients had a stroke caused by a blood clot in the brain, known as an ischaemic stroke, nine patients had a stroke caused by a brain haemorrhage, and one patient had a stroke caused by inflammation in the blood vessels of the brain.
The researchers said age data was available for 74 of the patients who experienced a stroke, and the majority were over 60 years of age. According to the study, 39 patients showed signs of confusion or changes in behaviour reflecting an altered mental state. Of these, it noted that nine patients had unspecified brain dysfunction, known as encephalopathy, and seven people had inflammation of the brain, medically termed encephalitis.
The remaining 23 patients with an altered mental state were diagnosed with psychiatric conditions, of which the vast majority (92 percent) were determined as new diagnoses by the notifying psychiatrist.
These patients with psychiatric diagnoses included ten patients with a new-onset psychosis, and six patients with a dementia-like syndrome, the study noted.
According to the researchers, seven patients had signs of a mood disorder, including depression and anxiety. While most of the psychiatric diagnoses were determined as new by the notifying psychiatrist, they said there is also a possibility that these were undiagnosed before the patient developed Covid-19.
The researchers speculated that the high proportion of younger patients diagnosed with psychiatric conditions could be because these patients may be more likely to be referred to a psychiatrist or other specialist doctors.
Confusion or behaviour changes in older patients may be more likely to be attributed to delirium and not investigated further, they explained.
According to scientists, it is not possible to draw conclusions based on the study about the total proportion of Covid-19 patients likely to be affected by neurological and psychiatric complications.
They said detailed long-term studies are needed in order to confirm if there is any link between Covid-19 infection and the onset of psychiatric or neurological complications in younger patients.