Study Finds Most Violent Offenders with Psychosis Are Known to Mental Health Services

The majority of people with psychosis who commit violent offences are known to mental health services which struggle to meet the needs of this group.

Three out of four people who committed serious violent offences in NSW and were found not guilty due to mental illness had visited at least one mental health service prior to the attack, a study led by UNSW Sydney has found.

The study, which was reported today in the Australian and New Zealand Journal of Psychiatry, examined 477 cases of violent offences committed by people with a mental illness that were recorded by the NSW Mental Health Review Tribunal between 1990 and 2016. It found that while most of the offenders had contact with health services prior to the violent offence, many were not identified as having a psychotic illness.

UNSW School of Psychiatry’s Professor Kimberlie Dean said that if services for those with severe and complex mental health problems were adequately resourced, there may be opportunities for health and legal authorities to intervene more effectively and minimise the chances of individuals harming themselves or others while in an untreated state of psychosis.

“This is not to say that the psychosis may have emerged or deteriorated in the period between contact with the health services and the time of the offence,” she said.

“For those seen by mental health services prior to violence but not identified as having psychosis, there may have been emerging or underlying psychosis that was missed or attributed to other conditions or that the diagnosis was not yet clear.”Timely research
The research comes as the country reels from the horrific attack at Bondi Junction last month that left six people dead. A 40-year-old man stabbed people in a shopping centre in an apparent state of psychosis.

While declining to comment on the circumstances of this case, Prof. Dean told ABC radio in the aftermath of the event that it wasn’t always clear whether much could have been done in the present conditions of mental health support services to have prevented a violent act.

“I think this case does highlight that there is a group of people in our community … with severe and complex mental health problems … who I think most clinicians working in the area would say are not sufficiently well served by our current services in Australia. I think services, especially public mental health services, state-based public mental health services, are really stretched,” Prof. Dean said.

Health service contact
While three quarters had visited mental health services at some point prior to their offence (with two-thirds visiting in the prior 12 months), an even higher number – or four in five – had visited a health service of any kind, such as a visit to the hospital emergency department, a hospital admission or visiting an outpatient mental health service. Almost half had contact within one month of the violent crime, while a quarter had contact within a week.

Most of the people with mental illness who offended were male (84 per cent) and were aged between 30 and 60 at the time of the offence, while almost half of the sample had a history of child abuse or neglect. The most common primary diagnoses were schizophrenia (84 per cent) while additional conditions included substance use disorder (67 per cent) and head injury (35 per cent).

“Almost all of the people in this cohort were later diagnosed as having a psychotic illness, but many weren’t recorded as having this illness at their most recent contact with health services,” said Prof. Dean.

“The extent to which better resourced mental health services may have been able to address the needs of these patients and reduce their risks of poor outcomes, including violence, is difficult to estimate but it is clear that more needs to be done for this group.”

Barriers to mental health care
Previous studies of the duration of untreated psychosis have identified multiple barriers to care, including lack of understanding the psychotic symptoms by the affected person and their relatives, and lack of awareness of services that are available, Prof. Dean said.

“The findings in our study suggest that being from a non-English speaking background can be a further barrier to care,” she said.

“This could be due to cultural interpretations of symptoms and treatment of mental illness, reduced awareness of available services and difficulties communicating with clinicians.”

Recommendations
Prof. Dean said it was worth noting that it was very rare for people diagnosed with severe mental illness to be violent. This makes identifying individuals at risk of violent offences more difficult for stretched mental health and hospital services.

“If we improved the adequacy, effectiveness and continuity of care that people with mental illnesses need, we would reduce the likelihood of a range of poor outcomes for people, potentially including offending.

“And if we were able to recognise the early warning signs of severe psychotic mental illness and intervene earlier, we may be able to improve outcomes for people with emerging psychosis and possibly prevent some acts of serious violence.”