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