New research has found that nearly 1 person in 5 diagnosed with COVID-19 is diagnosed with a psychiatric disorder like anxiety, depression or insomnia within three months.

The analysis was conducted by researchers at the University of Oxford, using electronic health records for 69.8 million patients in the U.S. — including more than 62,000 diagnosed with COVID-19.

Compared with patients who had experienced certain other health events this year — such as influenza, kidney stones or a major bone fracture – those diagnosed with COVID-19 were more likely to have a subsequent psychiatric diagnosis in the following 14 to 90 days.

"The incidence of any psychiatric diagnosis in the 14 to 90 days after COVID-19 diagnosis was 18.1%," the study found, including 5.8% that was a first diagnosis. The research was published Monday in Lancet Psychiatry.

People recovering from COVID-19 were about twice as likely to be diagnosed with a mental health disorder as compared with someone who had the flu, says Paul Harrison, professor of psychiatry at Oxford and one of the study's authors.

"That was within just the first three months," he says. "We of course don't know, in longer-term follow-ups, whether these risks will go on increasing — or whether once you get to three months, then the risks after you've had COVID really go back to the baseline risks that all of us experience."

The study found that the relationship between mental illness and COVID-19 is actually bidirectional: People with psychiatric diagnosis were about 65% more likely to be diagnosed with COVID-19 than people without.

It's unclear exactly why. The study controlled for certain factors, including physical risk factors and those who were having serious housing and economic difficulties – but the risk persisted. That's consistent with another recent large study using data from a different U.S. electronic health network that found increased risk of COVID-19 infection and mortality in people with mental disorders.

Risk of anxiety disorders increase post-COVID-19

But aren't most of us experiencing some level of anxiety right now, given the global pandemic?

What the study is talking about here is something more severe, says Harrison. "To get a diagnosis of an anxiety disorder, assuming the diagnostic tests were done correctly — this is more than simply the anxiety we're all feeling very, very reasonably because of the circumstances many people have lived through over the last few months."

He also points to the design of the study, which compared mental health diagnoses in people recovering from COVID-19 with those in people recovering from other medical events during the same time period: "They're all comparisons made between January and August this year when everybody was living through COVID, regardless of the illness that had taken them to see their doctor in the first place."

The researchers were able to differentiate somewhat for severity of COVID-19 cases — for instance, they found that someone hospitalized for COVID-19 had a higher risk of getting a psychiatric diagnosis than someone who did not need hospitalization. But the data did not offer enough granularity to say whether someone who was in an intensive care unit for COVID-19 was more likely to get a psychiatric diagnosis than someone who was in the ICU for something else.

Researchers also found an increased risk of dementia in those recovering from COVID-19. Harrison says it's yet not clear why that is, but it may be that some people were already developing dementia and it wasn't recognized until the patients saw a doctor for their COVID-19 symptoms.

Lauri Pasch is a clinical psychologist at University of California, San Francisco, where she has been working with patients at a special rehabilitation clinic for those who've been hospitalized for COVID-19.

"We're seeing a lot of anxiety, a lot of fear, a lot of sadness, a lot of sense of isolation," she says.

She says some post-COVID-19 patients describe sleep problems and distressing dreams: "Like waking up and feeling like you're back into the hospital. Waking up remembering really difficult aspects of having COVID, where you felt like you couldn't breathe. You felt like you were going to die."

Many patients say that during their illness and recovery, their thoughts have often turned to death. They think about losing family members and grapple with things undone in their lives. And some COVID-19 "long-haulers" describe persistent foggy minds and memory problems.

'We're seeing a lot of gratefulness'

But while some patients are diagnosed with anxiety disorders in the three months after having COVID-19, the large majority are not.

And Pasch says some patients describe the entirely opposite experience.

"We're seeing a lot of gratefulness — that feeling that friends and family were there for them in a way that they didn't expect, and feeling really grateful for that. Feeling like celebrating life."

She says some patients who had really difficult hospital stays say things like "I feel like I get a second chance at life" and "I'm going to make myself a better person," now that they have survived.

Pasch and her clinic colleagues call this "post-traumatic growth" – the inverse of post-traumatic stress.

She speculates, however, that people hospitalized for the disease in more overwhelmed hospital systems may be more likely to experience post-traumatic stress.

Researchers at Oxford, UCSF and elsewhere are still gathering data on post-COVID-19 mental health over the longer term. But Pasch says that she expects that in most cases, the post-traumatic stress symptoms of COVID-19 will subside.

"What I've been telling patients [is] it's going to be a slow and gradual improvement," she says, noting that younger patients often feel the frustration of a long recovery most acutely. "It's extremely frustrat[ing] to have a condition that's so scary, so much unknown, and just feel like I'm not getting back to my normal and wondering, is that the new me?"

To which Pasch and her colleagues can only say: We have to wait and see. "We don't expect it to be. But that's a very scary experience."

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