title: Schizophrenia with onset at the extremes of adult life.
abstract: OBJECTIVE
  To define the epidemiology, phenomenology, premorbid and risk factors in patients with the first manifestation of a schizophrenia-like illness after the age of 60 years, and compare them with patients with an onset before the age of 25 years.
  
  
  METHODS
  All contacts for a non-affective psychotic illness across all ages of onset were ascertained through a psychiatric case register; patients were rediagnosed according to operationalized criteria for psychotic illness, and those with a very early and very late onset compared.
  
  
  METHODS
  Phenomenological, premorbid and aetiological parameters were compared in the two groups, using risk ratios and 95% confidence intervals.
  
  
  RESULTS
  Very late onset patients (N = 72) were, compared to their very early onset counterparts (N = 192), more likely to be female, have good premorbid functioning and development history, and to exhibit persecutory delusions and hallucinations; they were less likely to have negative schizophrenic symptoms, to have a positive family history of schizophrenia, or have suffered pregnancy or birth complications.
  
  
  CONCLUSIONS
  The results highlight premorbid, aetiological and phenomenological differences between patients with the onset of a schizophrenia-like illness at the extremes of adult life, and suggest it is premature to consider the two groups to be merely different manifestations of the same illness.
authors.affiliation: Department of Psychological Medicine, Kings College Hospital London, UK.
authors.forename: D J
authors.initials: DJ
authors.lastname: Castle
authors.forename: S
authors.initials: S
authors.lastname: Wessely
authors.forename: R
authors.initials: R
authors.lastname: Howard
authors.forename: R M
authors.initials: RM
authors.lastname: Murray
mesh_terms: D000328:Adult; D000367:Age Factors; D017668:Age of Onset; D000368:Aged; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D012559:Schizophrenia / Q000145:classification / Q000453:epidemiology / Q000209:etiology; D012565:Schizophrenic Psychology; D012737:Sex Factors