title: Further evidence of a cumulative effect of social disadvantage on risk of psychosis.
abstract: BACKGROUND
  A growing body of evidence suggests that indicators of social disadvantage are associated with an increased risk of psychosis. However, only a few studies have specifically looked at cumulative effects and long-term associations. The aims of this study are: To compare the prevalence of specific indicators of social disadvantage at, and prior to, first contact with psychiatric services in patients suffering their first episode of psychosis and in a control sample. To explore long-term associations, cumulative effects, and direction of effects.
  
  
  METHODS
  We collected information on social disadvantage from 332 patients and from 301 controls recruited from the local population in South London. Three indicators of social disadvantage in childhood and six indicators of social disadvantage in adulthood were analysed.
  
  
  RESULTS
  Across all the domains considered, cases were more likely to report social disadvantage than were controls. Compared with controls, cases were approximately two times more likely to have had a parent die and approximately three times more likely to have experienced a long-term separation from one parent before the age of 17 years. Cases were also more likely than controls to report two or more indicators of adult social disadvantage, not only at first contact with psychiatric services [odds ratio (OR) 9.5], but also at onset of psychosis (OR 8.5), 1 year pre-onset (OR 4.5), and 5 years pre-onset (OR 2.9).
  
  
  CONCLUSIONS
  Greater numbers of indicators of current and long-term exposure are associated with progressively greater odds of psychosis. There is some evidence that social disadvantage tends to cluster and accumulate.
authors.affiliation: Department of Psychosis Studies,Institute of Psychiatry, Psychology & Neuroscience, King's College London,London,UK.
authors.forename: S A
authors.initials: SA
authors.lastname: Stilo
authors.affiliation: Department of Health Service & Population Research,Institute of Psychiatry, Psychology & Neuroscience, King's College London,London,UK.
authors.forename: C
authors.initials: C
authors.lastname: Gayer-Anderson
authors.affiliation: Department of Health Service & Population Research,Institute of Psychiatry, Psychology & Neuroscience, King's College London,London,UK.
authors.forename: S
authors.initials: S
authors.lastname: Beards
authors.affiliation: Department of Health Service & Population Research,Institute of Psychiatry, Psychology & Neuroscience, King's College London,London,UK.
authors.forename: K
authors.initials: K
authors.lastname: Hubbard
authors.affiliation: Department of Health Service & Population Research,Institute of Psychiatry, Psychology & Neuroscience, King's College London,London,UK.
authors.forename: A
authors.initials: A
authors.lastname: Onyejiaka
authors.affiliation: Department of Health Service & Population Research,Institute of Psychiatry, Psychology & Neuroscience, King's College London,London,UK.
authors.forename: A
authors.initials: A
authors.lastname: Keraite
authors.affiliation: Department of Health Service & Population Research,Institute of Psychiatry, Psychology & Neuroscience, King's College London,London,UK.
authors.forename: S
authors.initials: S
authors.lastname: Borges
authors.affiliation: National Institute for Health Research (NIHR) Mental Health Biomedical Research Centre at South London and Maudsley NHS Foundation Trust and King's College London,London,UK.
authors.forename: V
authors.initials: V
authors.lastname: Mondelli
authors.affiliation: Department of Psychosis Studies,Institute of Psychiatry, Psychology & Neuroscience, King's College London,London,UK.
authors.forename: P
authors.initials: P
authors.lastname: Dazzan
authors.affiliation: National Institute for Health Research (NIHR) Mental Health Biomedical Research Centre at South London and Maudsley NHS Foundation Trust and King's College London,London,UK.
authors.forename: C
authors.initials: C
authors.lastname: Pariante
authors.affiliation: National Institute for Health Research (NIHR) Mental Health Biomedical Research Centre at South London and Maudsley NHS Foundation Trust and King's College London,London,UK.
authors.forename: M
authors.initials: M
authors.lastname: Di Forti
authors.affiliation: Department of Psychosis Studies,Institute of Psychiatry, Psychology & Neuroscience, King's College London,London,UK.
authors.forename: R M
authors.initials: RM
authors.lastname: Murray
authors.affiliation: Department of Health Service & Population Research,Institute of Psychiatry, Psychology & Neuroscience, King's College London,London,UK.
authors.forename: C
authors.initials: C
authors.lastname: Morgan
mesh_terms: D000293:Adolescent; D000328:Adult; D000069586:Adult Survivors of Child Adverse Events / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D008131:London / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D011618:Psychotic Disorders / Q000453:epidemiology*; D012959:Socioeconomic Factors; D035862:Vulnerable Populations / Q000706:statistics & numerical data*; D055815:Young Adult
keywords: Causality; environment; epidemiology; reverse causation; schizophrenia; social adversity; unemployment