Three weeks after the Brexit referendum in 2016, a man in his 40's was brought to a UK emergency room by paramedics.
His wife had become concerned after he began spending more time on social media, stopped sleeping, experienced heightened stress about racism, and thought people were spying on him. Soon he became agitated and started throwing objects around his home.
After arriving at the hospital, the strange symptoms continued; he tried to "burrow" through the floor with his hands to get out of the room, he believed people were trying to kill him and he said he could hear voices.
According to his wife, the symptoms began after the Brexit referendum results had been declared on 24 June.
The case, published in leading medical journal the BMJ on Wednesday, is believed it to be the first known instance of acute and transient psychotic disorder (ATPD) - where psychotic symptoms appear within two weeks but dissipate within three months - brought on by Brexit.
In the first reported case of it's kind, a man in the UK has been diagnosed with acute psychosis brought on by Brexit. Source: AAP
“Political events can be a source of significant psychological stress,” Dr Mohammad Zia Ul Haq Katshu, who treated the patient, wrote in the report.
He also noted that the man had been experiencing family and work stress.
Australian mental health expert Dr Michael Musker told SBS News the long-term media coverage of Brexit uncertainty would likely affect "the whole community of the UK".
"People have been listening to the issue of Brexit for the last three years now. If you have an anxious disposition you're going to be worrying about this," he said.
"Particularly when they're told that there might be food shortages, they may run out of the medication, that the pound might become worthless ... when you hear these stories even the average person would feel anxious."
Dr Musker said it was not unusual for people who are already experiencing anxiety to attach those feelings to something stressful in the news.
He described one of his own patients who, during the peak of threats from al-Qaeda, became psychotic and believed the group was following him.
Surveys conducted in the UK following Brexit found that leaving the European Union was the most common source of anxiety for young people. Similar results were recorded in the US after the 2016 Presidential election.
"The uncertainty and unpredictability tied to the future of our nation is affecting the health and well-being of many Americans in a way that feels unique to this period in recent history," American Psychological Association (APA) chief executive Arthur Evans said in 2017.
APA survey results from the time found 63 per cent of Americans said the future of the nation was a "very or somewhat significant source of stress".
More than six in ten British people surveyed in April this year also believed uncertainty over Brexit was bad for mental health.
Leading up to the psychotic episode, the man, who remained anonymous in the report, described talking about racial issues and his anxieties around Brexit with a friend in the US who was experiencing similar stress over the 2016 election.
The patient did not have a family history of mental illness and did not abuse alcohol or drugs.
In one instance, during the episode, he recalled believing that a hospital interview room was in the basement of a building that was about to "be pulled down in a 9/11 style attack".
"I spent the entire time studying the walls and exit doors and watching people through the narrow window in the fire door to try and work out whether they were entering or evacuating the building," he said. "And if there was any hope of escape."
The report comes amid concerns from child psychologists about the rise of "eco-anxiety" - anxiety specifically related to climate change - and its effects on young Australians.
A new survey from youth mental health organisation ReachOut found that 80 per cent of students reported feeling "somewhat or very anxious" about climate change, with almost half experiencing climate anxiety on a weekly basis.
"When we look at climate change, we more or less say ... we're heading in towards a cliff edge, so it's quite natural for young people to start worrying about their future," Dr Musker said. "There is a definite rise in anxiety in society."
ReachOut has released resources specifically for people suffering "eco-anxiety" or "ecological grief", urging young Australians to take a break from climate news and activism if they are feeling overwhelmed.
Dr Musker urged people experiencing anxiety about the world to take breaks from consuming media and use mindfulness to focus on positive things that will happen in the future.
"If we only focus on the negative, that the world is doomed, then it's undoubted that young people will feel anxious about that," he said.
"If you have an anxiety disorder or panic disorder you can certainly be tipped over the edge by these social issues."
