Urban Birth, Urban Living, and Work Migrancy: Differential Effects on Psychotic Experiences Among Young Chinese Men.

Background: Urban birth and urban living are associated with increased risk of schizophrenia but less is known about effects on more common psychotic experiences (PEs). China has undergone the most rapid urbanization of any country which may have affected the population-level expression of psychosis. We therefore investigated effects of urbanicity, work migrancy, and residential stability on prevalence and severity of PEs. Methods: Population-based, 2-wave household survey of psychiatric morbidity and health-related behavior among 4132 men, 18-34 years of age living in urban and rural Greater Chengdu, Sichuan Province, China. PEs were measured using the Psychosis Screening Questionnaire. Results: 1261 (31%) of young men experienced at least 1 PE. Lower levels of PEs were not associated with urbanicity, work migrancy or residential stability. Urban birth was associated with reporting 3 or more PEs (OR: 1.63; 95% CI: 1.25-2.11), after multivariable adjustment, with further evidence (P = .01) this effect was restricted to those currently living in urban environments (OR: 1.78; 95% CI: 1.16-2.72). Men experiencing a maximum of 5 PEs were over 8 times more likely to have been born in an urban area (adjusted odds ratio [AOR] 8.81; 95% CI 1.50-51.79). Conclusions: Men in Chengdu, China, experience a high prevalence of PEs. This may be explained by rapid urbanization and residential instability. Urban birth was specifically associated with high, but not lower, severity levels of PEs, particularly amongst those currently living in urban environments. This suggests that early and sustained environmental exposures may be associated with more severe phenotypes.