Social Psychiatry and Psychiatric Epidemiology

, Volume 37, Issue 10, pp 460–464

Does the urban environment independently increase the risk for both negative and positive features of psychosis?

  • Jim van Os
  • Manon Hanssen
  • Ron de Graaf
  • Wilma Vollebergh
ORIGINAL PAPER

DOI: 10.1007/s00127-002-0588-x

Cite this article as:
van Os, J., Hanssen, M., de Graaf, R. et al. Soc Psychiatry Psychiatr Epidemiol (2002) 37: 460. doi:10.1007/s00127-002-0588-x

Abstract

Background: Psychotic disorders are more common in urban environments. It is not known whether the increase in risk applies to both the positive and negative dimensions of psychosis. Methods: In a random general population sample of 7076, measures of positive and negative symptoms of psychosis were constructed using Composite International Diagnostic Interview (CIDI) data. Three CIDI observed items of flat affect, retarded speech and retarded movement served as indicators of a negative symptom variable. Results: Both negative and positive symptoms of psychosis were, independent of each other, associated with a five-level measure of population density of place of residence (adjusted OR negative symptoms: 1.42, 95 % CI: 1.18, 1.71; adjusted OR positive symptoms: 1.19, 95 % CI: 1.13, 1.24). These associations remained after exclusion of vulnerable individuals with any lifetime psychiatric disorder (n = 2910), any lifetime psychiatric treatment (n = 1352) and history of psychosis in the parents (n = 142). Conclusions: An environmental risk factor associated with urbanicity may act in early life to non-specifically influence risk for both negative and positive experience of psychosis, regardless of whether a formal psychiatric disorder is diagnosable.

Key words psychosis - urban environment - positive symptoms - negative symptoms

Copyright information

© Steinkopff Verlag 2002

Authors and Affiliations

  • Jim van Os
    • 1
  • Manon Hanssen
    • 1
  • Ron de Graaf
    • 3
  • Wilma Vollebergh
    • 3
  1. 1.Department of Psychiatry and Neuropsychology, Maastricht University, European Graduate School of Neuroscience, PO BOX 616, 6200 MD Maastricht, The Netherlands. j.vanos@sp.unimaas.nlNL
  2. 2.Division of Psychological Medicine, Institute of Psychiatry, London SE5 8AF, UKGB
  3. 3.The Netherlands Institute of Mental Health and Addiction, (Trimbos Institute), PO BOX 725, 3500 AS Utrecht, The NetherlandsNL