Are the increased rates of psychosis reported for the population of Caribbean origin in Britain an urban effect?

There is accumulating evidence that urban birth, upbringing and residence are associated with an increased risk for mental illness in general and psychotic illness in particular. With the many reports of the increased rates of psychotic illness in the population of Caribean origin in Britain, we suggest that this may be attributable to factors associated with the urban environment within which they have had to live their lives since migrating to Britain in the mid 1950s. The problems of upbringing are particularly useful in understanding the even greater rates of psychosis among the second generation population. We review the evidence also to suggest that the migrants were unlikely to be selectively vulnerable (and this therefore could nor be construed as a variation of social drift) and settled in cities because of greater employment opportunities but have been adversely affected by social isolation, deprivation and the experience of relative inequality, in British society Research findings seem to indicate that this effect is being mediated through social rather than biological terms but may need to be viewed more in terms of a loss of protective factors (which remain available for other groups in the society) than necessarily to an increase ill exposure to risk factors.