Mental disorder in the New South Wales prisoner population

To determine the prevalence of mental illness among prisoners in New South Wales (NSW), Australia.

Mental illness was examined in two NSW prisoner populations: (i) new receptions to the correctional system; and (ii) sentenced prisoners. Reception prisoners were screened at four male centres and one female centre in NSW. The sentenced population was randomly selected from 28 correctional centres across the state. Reception prisoners were screened consecutively whenever possible while the sentenced group was randomly selected as part of the 2001 Inmate Health Survey. We adopted the same instrument, Composite International Diagnostic Interview - Auto (CIDI-A), for diagnosing mental illness as used in the Australian National Survey of Mental Health and Wellbeing.

Overall, 43% of those screened had at least one of the following diagnoses: psychosis, anxiety disorder, or affective disorder. Reception prisoners suffered from mental illness to a greater extent than sentenced prisoners (46%vs. 38%). Women had higher levels of psychiatric morbidity than men (61%vs. 39%). Nine percent (9%) of all prisoners had experienced psychotic symptoms (due to any cause) in the prior 12 months. Twenty percent (20%) of all prisoners had suffered from at least one type of mood disorder and 36% had experienced an anxiety disorder. Posttraumatic stress disorder was the most common disorder, diagnosed in 26% of receptions and 21% of sentenced prisoners.

These findings confirm that prisoners are a highly mentally disordered group compared with the general community. Given the high prevalence of mental illness identified by this study, it is essential that prison mental health services be adequately resourced to address the demand and, at minimum, ensure that mental health does not deteriorate during incarceration.