title: Duration of untreated psychosis in adolescents: ethnic differences and clinical profiles.
abstract: BACKGROUND
  Duration of Untreated Psychosis (DUP) is an important measure associated with outcome of psychosis. This first study in the UK compared DUP between adolescent and adult-onset individuals and explored whether the adolescent-onset group showed variations in DUP that could be accounted for by sociodemographic and selected risk factors.
  
  
  METHODS
  This naturalistic cohort study included 940 new first-episode psychosis cases aged 14-35years (136 adolescent-onset versus 804 adult-onset psychotic individuals) referred to nine Early Intervention Services for Psychosis in London (2003-2009). Sociodemographic characteristics, age of onset, family history of mental illness, duration of untreated psychosis, suicidality and substance use information were collected at entry to the services.
  
  
  RESULTS
  Adolescents presented with significantly greater median DUP (179days) than adults (81days, p=0.005). Large differences in DUP were found amongst adolescent ethnic groups (median DUP: White: 454days; Black: 103days; Asian and mixed: 28.5days). In addition, younger age of onset and higher lifetime cannabis use were associated with longer treatment delay amongst adolescents.
  
  
  CONCLUSIONS
  This study of DUP in adolescent-onset psychosis found it to be approximately twice the length of DUP amongst adults. For the adolescent White sub-group, DUP was far greater than the UK Department of Health target (<3months). Both the high rates of lifetime cannabis use and the lower age of onset might explain the long DUP in this ethnic group. Physicians need to be particularly vigilant about identifying and managing early psychosis in adolescents.
authors.affiliation: Academic Unit of Child and Adolescent Psychiatry, Division of Brain Sciences, Imperial College London, UK. Electronic address: m.dominquez-barrera@imperial.ac.uk.
authors.forename: Maria-de-Gracia
authors.initials: MD
authors.lastname: Dominguez
authors.forename: Helen L
authors.initials: HL
authors.lastname: Fisher
authors.forename: Barnaby
authors.initials: B
authors.lastname: Major
authors.forename: Brock
authors.initials: B
authors.lastname: Chisholm
authors.forename: Nikola
authors.initials: N
authors.lastname: Rahaman
authors.forename: John
authors.initials: J
authors.lastname: Joyce
authors.forename: James
authors.initials: J
authors.lastname: Woolley
authors.forename: Jo
authors.initials: J
authors.lastname: Lawrence
authors.forename: Mark
authors.initials: M
authors.lastname: Hinton
authors.forename: Karl
authors.initials: K
authors.lastname: Marlowe
authors.forename: Katherine
authors.initials: K
authors.lastname: Aitchison
authors.forename: Sonia
authors.initials: S
authors.lastname: Johnson
authors.forename: Matthew
authors.initials: M
authors.lastname: Hodes
mesh_terms: D000293:Adolescent; D000328:Adult; D017668:Age of Onset; D000704:Analysis of Variance; D044466:Asian People; D044383:Black People; D016009:Chi-Square Distribution; D015331:Cohort Studies; D005260:Female; D006801:Humans; D016014:Linear Models; D008297:Male; D011569:Psychiatric Status Rating Scales; D011618:Psychotic Disorders / Q000175:diagnosis / Q000208:ethnology* / Q000628:therapy; D044465:White People; D055815:Young Adult
keywords: Adolescence; Age of onset; Cannabis; Duration of untreated psychosis; Ethnicity; First episode psychosis