MedWire News: Immigrants face a significantly increased risk of schizophrenia, particularly those with a cultural background that is distinctly different from that of the host nation, study results confirm.

"Being a small and culturally different minority, or having a different appearance, has been invoked to account for the increased prevalence of psychotic disorders among immigrants," explain Dr M Weiser, from Sheba Medical Center in Tel Hashomer, Israel, and team.

To investigate further, the researchers studied data on 661,792 adolescents who were screened by the Israeli Draft Board for military service. Of these, 557,154 were native-born Israelis and 104,638 came from immigrant families.

The team notes that the late 1980s and early 1990s large numbers of immigrants arrived in Israel. Most of these people came from the former Soviet Union, but a significant minority also came from Ethiopia.

The researchers found that, overall, first-generation immigrants were 1.62 times more likely to have been hospitalised for schizophrenia while second-generation immigrants were 1.41 times more likely to have hospitalised for the condition compared with native Israelis.

Further analysis revealed that Ethiopians were the most likely immigrant group to have been hospitalised for schizophrenia. Indeed, immigrants from Ethiopia were nearly three times more likely to have been treated for schizophrenia than Israeli natives.

"In line with previous studies, our findings suggest that both first- and second-generation immigrants are at increased risk for hospitalisation for schizophrenia relative to the native-born population," Dr Weiser and team write in the journal Psychological Medicine.

"Cultural dissimilarity from the host country and having a different physical appearance might be associated with [an even] greater risk for schizophrenia."

They add that doctors treating immigrants from diverse cultural backgrounds should be aware of their patients' susceptibility to mental health disorders.