aetiological factors

Last reviewed 01/2018

Aetiological factors in schizophrenia include:

  • hereditary factors:
    • it is generally accepted that there is a genetic component schizophrenia but size of the effect is unclear
    • studies of monozygotic twins have shown concordance rates in the development of schizophrenia varying between 30% and 60%
    • the concordance rate in dizygotic twins is 10-15%

  • pre-morbid "schizoid" personality is associated with the development of schizophrenia:
    • schizoid traits include abnormal shyness, hypochondriasis, fanaticism and eccentricity

  • childhood experiences

  • biochemical factors - LSD and amphetamines can both produce schizophrenic-like psychoses

  • physical factors - illnesses, operations, accidents or periods of reduced sleep can precipitate an acute schizophrenic psychosis or cause remission in an established schizophrenic

  • life events such as bereavement or loss of a job, may precipitate onset or remission of schizophrenia

  • cerebral tissue damage - head injury, cerebral tumour, Huntington's chorea and Wilson's disease occasionally produce schizophrenia-like disorders; temporal lobe epilepsy is associated with an increased incidence of schizophrenia; some schizophrenics have large ventricles