Presentations of psychosis with violence: variations in different jurisdictions. A comparison of patients with psychosis in the high security hospitals of Scotland and England

BACKGROUND: International literature is consistent on there being a significant relationship between psychosis and violence, less so on its extent and nature, but two main presentational types are increasingly recognized. In one, people are unremarkable before onset of illness and psychotic symptoms commonly drive violence; in the other, psychosis is preceded by childhood conduct problems, associated with personality disorder, and psychotic symptoms seem less relevant. AIMS: To explore the extent to which variations in aspects of social and service context in different jurisdictions affect presentational type among people admitted to high security hospitals. HYPOTHESES: There will be differences between jurisdictions in proportions of patients with pure psychosis or with psychosis and antecedent personality disorder, but symptom drive to violence will be more common in the pure psychosis group regardless of social, legal and service context. METHOD: Independently conducted record studies were used to compare high security hospital patients with psychosis in Scotland and England, all resident between 25 August 1992 and 13 August 1993. RESULTS: The cohorts were similar in offence histories, predominance of schizophrenia, age at first hospitalization for psychosis and first high security hospitalization. More Scottish patients had co-morbid substance misuse diagnoses and/or personality disorder than patients in England. Psychotic symptom drive to the index offence was, however, four times more likely in the pure psychosis groups, regardless of sex, ethnic group or country. Scottish patients spent less time in high security after the index act. CONCLUSIONS: Our hypotheses were sustained. Knowledge about lifestyle before onset of psychosis is important for interpreting literature on how psychotic symptoms relate to violence. This may also influence longer term outcome, although the shorter length of secure hospital stay in Scotland was perhaps affected more by greater availability of open 'step-down' beds