Incidence of schizophrenia and other psychoses is greater in urban than rural areas, but the reason remains unclear. Various studies have found the link between living in the city and severe mental illness, and none have determined a specific cause. A new study claims to have the explanation. The study examined a group of over 200,000 people born between 1972 and 1977 whose medical history was cross-referenced with demographic, school, municipality, and county information.
The study, published this month in the Archives of General Psychiatry examined whether individual, school, or area characteristics could be associated with psychosis and whether the effects of individual characteristics on risk of psychosis varied according to location.
The incidence of psychosis was significantly higher among people living in urban settings as compared to those living in the country. Further data analysis showed that psychosis appears to be a reflection of the increased social fragmentation that has become a feature of city living.
The principal researcher, Dr. Stanley Zammit of the Center for Neuropsychiatric Genetics and Genomics of Cardiff University, said that previous studies had found that the severity of schizophrenia risk depends on the context of the living situation, with increased risk found for those living in an area with few people of their own ethnicity.
Of this study, Dr Zammit says that "it was somewhat surprising that we found this sort of context-dependent effect across a range of characteristics: ethnicity, social fragmentation, and deprivation. Although it makes sense that such an effect would not be restricted to ethnicity but to potentially any characteristic that might define someone as being different from their peers as they grow up."
With the caution that is characteristic of studies that avoid the presumption of absolute revelation, the researchers point out that much more investigation is needed before it could be said (if ever) that living in the city causes schizophrenia. What can be said from this and other similar studies, however, is that there is a greater risk of developing a severe mental illness such as psychotic disorder for people who live in a predominantly urban setting. Is this enough to make you want to live in the boonies? Maybe not. But this may be another consideration for a move to the more distant ‘burbs.