Late-onset schizophrenia and very-late-onset schizophrenia-like psychosis: an international consensus. The International Late-Onset Schizophrenia Group

Am J Psychiatry. 2000 Feb;157(2):172-8. doi: 10.1176/appi.ajp.157.2.172.


Objective: Although schizophrenia is generally regarded as an illness with onset in late adolescence or early adult life, a sizeable minority of patients first become ill in middle or old age. Inconsistencies in diagnostic systems and nomenclature, coupled with a tendency among most schizophrenia researchers to ascribe late-onset psychoses to organic factors, have led to such cases occupying an ambiguous position in relation to schizophrenia. Through systematic review of the literature and publication of a consensus statement from an international group of experts in the field, this article aims to clarify the positions of late-onset schizophrenia and very-late-onset schizophrenia-like psychosis.

Method: The authors conducted a MEDLINE literature review and developed a consensus statement summarizing the findings from 2 days of debate and discussion by members of the International Late-Onset Schizophrenia Group.

Results: The group achieved consensus on diagnosis, nomenclature, treatment guidelines, and future research directions.

Conclusions: In terms of epidemiology, symptom profile, and identified pathophysiologies, the diagnoses of late-onset schizophrenia (illness onset after 40 years of age) and very-late-onset schizophrenia-like psychosis (onset after 60 years) have face validity and clinical utility. General adoption of these categories will foster systematic investigation of such patients.

Publication types

  • Consensus Development Conference
  • Research Support, Non-U.S. Gov't
  • Review
  • Systematic Review

MeSH terms

  • Adolescent
  • Adult
  • Age of Onset*
  • Aged
  • Antipsychotic Agents / therapeutic use
  • Brain / diagnostic imaging
  • Child
  • Clinical Trials as Topic
  • Female
  • Forecasting
  • Humans
  • Male
  • Middle Aged
  • Neuropsychological Tests
  • Practice Guidelines as Topic
  • Radiography
  • Radionuclide Imaging
  • Research Design / trends
  • Risk Factors
  • Schizophrenia / diagnosis*
  • Schizophrenia / drug therapy
  • Schizophrenia / epidemiology*
  • Terminology as Topic
  • Treatment Outcome


  • Antipsychotic Agents