Immigration and psychosis

Migration is an accepted risk factor for schizophrenia but the level of risk in second-generation immigrants in unclear. A team of researchers from McGill University in Canada reviewed 21 studies into psychosis among immigrants. They found that while first-generation immigrants were 2.3x as likely to develop psychosis as other people second-generation immigrants were 2.1x as likely. While there was no significant difference in risk between the generations there were wide variations in levels of psychosis between different ethnic groups and different host countries.

Bourque, F., van der Ven, E. and Malla, A. - A meta-analysis of the risk for psychotic disorders among first- and second-generation immigrants Psychological Medicine (2011), 41: 897-910

Autism and immigration

Over the past thirty years occasional studies have pointed to an increased frequency of autism in the children of immigrant parents but the factors that might lie behind this are complicated and there has been relatively little research into this issue. Daphne Keen from St George's Hospital in London led a team studying 428 children with autism who had been treated, over a six-year period, by child development services in South-West London. They found that mothers born outside Europe had a significantly higher risk of having a child with autism-spectrum disorder. Mothers from the Caribbean had the highest risk and mothers of Black ethnicity had a significantly higher risk compared to White mothers. However, a statistical analysis of the results showed that most of the increased risk was due to immigration rather than ethnicity.

Keen, D.V., Reid, F.D. and Arnone, D. - Autism, ethnicity and maternal immigration British Journal of Psychiatry April 2010, 196(4), 274-281