A large study from the United Kingdom reveals the breadth of neurologic and neuropsychiatric complications of COVID-19 infection, including stroke, psychosis, altered mental state, and dementia-like syndrome.

“Clinicians should be alert to the possibility of patients with COVID-19 developing these complications and, conversely, of the possibility of COVID-19 in patients presenting with acute neurological and psychiatric syndromes,” the investigators, from the CoroNerve Study Group, write.

The report was published online June 25 in Lancet Psychiatry.

Altered Mental State, New-Onset Psychosis

During the exponential phase of the pandemic, Benedict Michael, PhD, from the University of Liverpool, and colleagues set up an online case reporting platform called CoroNerve to investigate the range of COVID-19 complications that affect the brain.

Between April 2 and April 26, clinicians representing neurology, stroke, psychiatry and intensive care described 153 patients (median age, 71 years) hospitalized with COVID-19 who were displaying some type of neuropsychiatric complication.

Among the 125 patients (82%) with full clinical details, 114 (91%) had confirmed SARS-CoV-2 infection, 6 (5%) had probable infection and 4 (9%) had possible infection.

The most common presenting complication was a cerebrovascular event, reported in 77 (62%) patients, of whom 57 (74%) had ischemic stroke, 9 (12%) intracerebral hemorrhage, and 1 (1%) CNS vasculitis. Cerebrovascular events were more common among patients older than 60 years.

Altered mental status (defined as an acute alteration in personality, behavior, cognition, or consciousness) was the second most common complication, affecting 39 (31%) patients. Of these, 9 (23%) had unspecified encephalopathy and 7 (18%) had encephalitis.

The remaining 23 (59%) patients with altered mental status fulfilled the clinical case definitions for psychiatric diagnoses and 21 (92%) of these were new diagnoses.

Ten (43%) of 23 patients with neuropsychiatric disorders had new-onset psychosis, 6 (26%) had a neurocognitive (dementia-like) syndrome, and 4 (17%) had an affective disorder. Seven (30%) patients had another psychiatric disorder, including 1 case of catatonia and 1 case of mania.

About half of the patients who experienced altered mental status were younger than 60 years.

Although most psychiatric diagnoses were determined as new by the notifying clinician, the possibility that they were present but undiagnosed before the patient developed COVID-19 can’t be excluded, the authors note.

This study is “an important early step toward defining neurological complications in COVID-19 patients, which will help with health policy planning as well as informing the immediate next steps in COVID-19 neuroscience research,” Michael said in a statement.

“We now need detailed studies to understand the possible biological mechanisms underlying these complications so that we can explore potential treatments,” he added.

Coauthor Sarah Pett, PhD, from University College London, UK, said studies are needed to understand brain complications in people with milder COVID-19 disease who are not sick enough to be hospitalized.

“Our study provides the foundations for larger hospital and community-based studies. These studies will help inform on the frequency of these brain complications, who’s most at risk of getting them, and ultimately how best to treat,” Pett said in the release.

Lon-term Impact?

Reached for comment, Brittany LeMonda, PhD, senior neuropsychologist at Lenox Hill Hospital in New York City, said the high rates of neuropsychiatric complications of COVID-19 are “very concerning.”

While there are some reports of neurologic complications with other respiratory illnesses, “the rates of these complications in COVID-19 have been much higher than we initially thought,” LeMonda told Medscape Medical News.

“I don’t think we have enough evidence right now to know exactly how long these complications will last. Typically they are thought to resolve as an infection improves but we don’t know that much about COVID-19,” said LeMonda, who was not involved with the study.

As the pandemic wanes, LeMonda said psychiatrists, neurologists, and neuropsychologists could see a “huge wave” of patients with residual neuropsychiatric effects of COVID-19.

Although the current study focused on hospitalized COVID-19 patients, LeMonda said she “suspects that some patients who had milder illness might also come in with some of these symptoms after their illness resolves.”

Michael and LeMonda have disclosed no relevant financial relationships.