The risk of psychosis among first- and second-generation immigrants to the
United Kingdom appears to be similar.
That's an important finding because it underscores the well-documented
elevated risk for psychosis among immigrants and clarifies that the risk does
not diminish depending on how long immigrant groups have been residing in the
The finding was from the East London First-Episode Psychosis Study and was
reported in the November Archives of General Psychiatry.
The study also supports the concept that the elevated risk is likely
related to environmental factors.
"This suggests that within ethnic groups, the cumulative
effect—or load—of factors that serve to increase the risk of
psychoses in black and minority ethnic groups is probably similar across generations,
although the exact specification of these factors will probably
differ," wrote Jeremy Coid, M.D., and colleagues. "For example,
the pressures faced by first-generation black Caribbean immigrants in the
1950s and 1960s were very different from those faced by their
second-generation counterparts in the 1990s and beyond. Assuming for a moment
that discrimination is a risk factor for psychoses in black and minority
ethnic populations, our results support the notion that its cumulative effect
is roughly similar across generations, although the form of discrimination has
probably changed over generations."
Coid is with the Forensic Psychiatry Research Unit at St Bartholomew's
The study was a population-based epidemiological survey during a two-year
period among 484 patients with first-episode psychosis in three inner-city
boroughs of East London, England. The area is exclusively inner city,
characterized by high levels of socioeconomic deprivation; historically, it
has hosted a number of diverse ethnic groups who immigrated to the United
All potential cases of psychosis presenting to psychiatric services for the
first time (including adult community mental health teams, inpatient units,
forensic services, learning disability services, adolescent mental health
services, and drug and alcohol units) were screened. Patients were classified
as being in one of six ethnic subgroups: white British, white other
(predominantly Irish and European groups), black Caribbean (including black
other, mixed white, and black Caribbean groups), black African, Asian (Indian,
Pakistani, and Bangladeshi groups), and all other ethnic groups (Chinese,
other Asian, and other mixed ethnic groups).
Rates in each ethnic group were standardized using the 2001 census
population of England and Wales stratified by sex and age.
The researchers found higher incidence rates of both nonaffective and
affective psychoses for all of the black and minority ethnic subgroups
compared with white British individuals. The risk of nonaffective psychoses
for first- and second-generations varied by ethnicity: only black Caribbean
second-generation individuals were at significantly greater risk, compared
with their first-generation counterparts.
No significant differences between first and second generations were
observed in other ethnic groups. Asian women but not men of both generations
were at increased risk for psychoses, compared with white British
The researchers postulated that the greater risk for second-generation
black Carribean individuals may be due to the fact that the first-generation
cohort in that ethnic group tends to be older than in the other groups and to
have bypassed the period of 18-24 years of age, when individuals are at
greatest risk of psychosis.
"For other ethnic groups such as the black African and white other
groups, where the modal age group in each generation was closer to the main
period of risk of psychoses, the elevated risk of psychoses was comparable
between first- and second-generation immigrants," Coid and colleagues
Ezra Susser, M.D., Dr.P.H., a researcher who has also studied psychosis
among immigrant groups and who reviewed the report for Psychiatric News, said
it adds to the picture of elevated risk for immigrant ethnic groups that has
been reported in a number of studies.
"It's further evidence that something in the socioeconomic
environment is causing the increased risk," Susser said. "And
whatever it is has to be common across first- and second-generation
He is a professor of epidemiology at Columbia University's Mailman School
of Public Health and a professor of psychiatry at the New York State
Susser was one of the lead investigators in a study showing that immigrants
living in neighborhoods where their own ethnic group represents a very small
proportion of the population are at increased risk for psychosis, a finding
that points to the influence of social mechanisms—social networks,
language fluency, stigma, discrimination and harassment, and other
environmental and psychosocial factors—in the etiology of some cases of
schizophrenia (Psychiatric News, February 1).
An abstract of "Raised Incidence Rates of All Psychoses Among
Migrant Groups: Findings From the East London First-Episode Psychosis
Study" is posted at< http://archpsyc.ama-assn.org/cgi/content/abstract/65/11/1250>."
Ethnic Density of Neighborhoods and Incidence of Psychotic Disorders
Among Immigrants" is posted at < http://ajp.psychiatryonline.org/cgi/content/full/165/1/66>.▪