The relatively common occurrence of schizophrenia in African-Caribbean populations living in Europe is used in this chapter as a model to discuss relationships among ethnicity, migration, and mental health. The phenomenon will be described, and possible causes will be discussed in the context of the theoretical framework that underpins the migration paradigm, set out by Rutter in Chapter 1.
Ødegaard (1932) was the first to moot the idea that certain migrant groups may be susceptible to schizophrenia in the years following their journey. He noted the phenomenon in Norwegian migrants to the Midwest of the United States in the early years of the 20th century. Studies in the United Kingdom began to report a much higher than expected incidence of schizophrenia in this group soon after their arrival in the 1950s and first half of the 1960s. Initial reports were confirmed and explored in a series of progressively more rigorous and sophisticated studies that will be reviewed in what follows (Hemsi, 1967; Kiev, 1965).
The schizophrenia incidence rate appears to be elevated 5- to 10-fold compared with the general population. Such an effect is almost as large as the association between smoking and lung cancer, something that, 30 years earlier, revolutionized understanding of the causes of that disease and paved the way for major and extant public health initiatives the world over. However, the schizophrenia and ethnicity association remains contentious and unexplained.