Refugees and some immigrants more likely to have psychotic disorders: study

May 11, 2015

By Emily Chan, CTV News |

The experience of moving to a new country may put refugees and some immigrants at a higher risk of psychotic disorders, a new study suggests.

The study, which was published in the Canadian Medical Association Journal on Monday, compared the rate of psychotic disorders in first-generation Canadians to the rate in the general Ontario population.

It found that immigrants from the Caribbean and refugees from East Africa and South Asia have a 1.5 to 2 times higher risk of schizophrenia and schizoaffective disorders. The study also found that refugees have a 25 per cent higher risk of psychotic disorders, compared to other immigrants.

On the other hand, the study suggested immigrants from northern and southern Europe and east Asia had half the risk of devloping a psychotic disorder.

The pattern of data “suggests that psychosocial and cultural factors associated with migration may contribute to the risk of psychotic disorders,” the report said. “Some groups may be more at risk, whereas others are protected.”

Paul Kurdyak, one of the study’s authors, said the findings match the results of similar studies around the world.

“There is this relationship between immigration and the risk of developing a psychotic disorder,” he said.

Researchers from the Institute for Clinical Evaluative Sciences and the Centre for Addiction and Mental health tracked nearly four million people for 10 years to reach their conclusions.

Kurdyak said the findings are substantial given that Canada receives about 250,000 new migrants a year. In Ontario, nearly 30 per cent of the province’s population is first-generation.

“Canada and Ontario in particular is a really interesting place to study this because there’s such a high rate of immigration,” Kurdyak said in a phone interview with “And certainly we attract immigrants from a much wider range of countries, than, say, European countries.”

Kurdyak said a combination of factors before, during, and after moving to Canada can affect immigrant mental health.

“I think the reason why we see the higher risk of psychotic disorders amongst some groups largely boils down to high rates of pre-migration stress and trauma,” he said. Once in Canada, racism against visible minorities and socioeconomic factors such as income and housing can also affect immigrant mental health.

For example, Kurdyak said, a wealthy skilled immigrant from northern Europe might experience less psychological stress than a refugee who has experienced violence or persecution in east Africa.
Kurdyak said the study shows how psychotic disorders are not merely biological phenomena, but are also affected by social factors. He hopes the study can be used in real life to help address mental health issues in Canada.

“We’ve identified specific populations that are risk,” Kurdyak said. “We need to really work to make sure that they have access to the support that they need, given the elevated risk that we’ve identified.”

In a country “built on immigrants,” helping newcomers should be a priority, Kurdyak said.
He added, “I think that Canadians should be very proud that we are a country that is so open and welcoming to immigrants.”

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