More supports needed to protect people with schizophrenia from extreme heat, experts say

British Columbia's 2021 heat dome killed people diagnosed with schizophrenia at a higher rate than those with any other chronic illness, according to recent findings from researchers at the B.C. Centre for Disease Control (BCCDC).

As extreme heat events are forecasted to become more common and intense, researchers and one advocate are calling for more public awareness and cooling centres for vulnerable people, including those with schizophrenia.

During the heat dome's hottest eight days in B.C., 134 people diagnosed with schizophrenia died, triple the average numbers of deaths during the same period from 2006 to 2020, found a peer-reviewed article published in journal GeoHealth in March.

That represents about eight per cent of all deaths recorded during the extreme heat event, while people with schizophrenia make up only about one per cent of the population, said a June opinion article published in the B.C. Medical Journal.

Even when controlling for other 25 other more common comorbid conditions, "the risk of death for people with schizophrenia was far larger than the risk for any of the other chronic illnesses," said Michael Lee, an epidemiologist with environmental health services at the BCCDC who co-authored both articles.

Older people with one or multiple chronic health conditions like heart or kidney disease were also more likely to die during the heat dome, found the March study, which linked provincial registries of chronic disease to recorded deaths in B.C.

"But the magnitude of increase in the risk was far larger for schizophrenia than for those traditional risk factors," said Lee.

No single solution

The elevated risk of death for people with schizophrenia is likely due to several factors, Lee and his colleagues wrote in June.

Disorganized thinking, delusion and hallucinations can make it difficult for them to recognize the risk extreme heat poses and seek shelter, Lee said, while certain antipsychotic medications prescribed to treat schizophrenia can also reduce the body's ability to regulate temperature.

Schizophrenia is also linked to higher rates of substance use disorder and other comorbidities, like diabetes, according to the March study.

But economic marginalization and social isolation also mean people with schizophrenia are more likely to be homeless or live in sub-standard housing, said Shirley Chan, president of Pathways Serious Mental Illness Society on the North Shore.

"They wouldn't know enough to get out of the heat, and if they're homeless or living in poor shelters … they wouldn't have access to cooler places," said Chan, whose adult daughter lives with schizophrenia.

Chan says her daughter was living in a tent in Vancouver's Strathcona Park during the 2021 heat dome, which made her extremely worried for her ability to stay cool.

There aren't enough appropriate housing units and supports for people with schizophrenia, whose hallucinations and delusions can make it difficult to keep traditional work and housing, said Chan.

"It isn't a choice to be sick, and having more housing and proper housing, with proper supports to be successful, is what we need," she said.

Chan also wants to see more outreach teams checking in on people who are homeless or living with schizophrenia, passing out water and directing people to cooling centres during extreme heat events.

Lee echoed Chan's concerns, noting the B.C. Coroners Service's findings that the majority of people who died in the 2021 heat dome did so in their homes without air-conditioning.

"It's not necessarily how hot it is outside that's a risk factor here, it's how hot it is inside people's houses during these extreme heat," said Lee.

Building more green spaces, requiring air conditioning and cooling devices in housing units, and opening more cooling centres can all save lives, he said. 

Health-care providers and public health messaging need to notify patients and their families of the risks posed by extreme heat, Lee added, and he encouraged the public to check in with people in their own lives who are living with schizophrenia.

"It's really up to all of us to reach out to those people before extreme heat events happen to see if they understand that they're at increased risks and whether they have plans in place," said Lee.