Violence in Schizophrenia Associated With Several Risk Factors at Diagnosis

Violence risk assessment at triage for people affected by schizophrenia spectrum disorders should consider the presence of antisocial behavior and violent victimization, substance use, male gender, and frequency of inpatient admissions, according to findings published in the Australia & New Zealand Journal of Psychiatry.

Henning Hachtel, MD, of the Department of Psychological Sciences at the Centre for Forensic Behavioural Science, at Swinburne University of Technology in Hawthorn, Victoria, Australia and the Universitare Psychiatrische Kliniken Basel at the University of Basel in Switzerland, and colleagues compared various risk factors for post-diagnostic violence in 1453 patients diagnosed with a schizophrenia spectrum disorder in the public mental health system in 2000 and 2005. 

Patients’ psychiatric history was extracted from the Victorian Psychiatric Case Register. These records were linked through a multistage deterministic-probabilistic approach with those on the Law Enforcement Assistance Program, a statewide register. Mental health and criminological variables were evaluated across the lifespan of an individual.

Gender, employment, non-violent offending, family incidents, violent and non-violent victimization, substance use, personality disorder, number of inpatient admissions, and history of noncompliance differed significantly across violent and non-violent subgroups (all P ≤.01 and at least small effect size). The investigators found more frequent and longer inpatient admissions in the violent subgroups (all P ≤.01). For the whole sample, sex, number of violent offences, non-violent offences, violent victimization, substance use, and number of inpatient admissions predicted post-diagnostic violence (X² (6)=188.13, P ≤.001). 

The investigators noted that in patients with a history of pre-diagnostic violence, a history of non-violent offending in the 18-month period pre-diagnosis was the strongest predictor of future violence (odds ratio=3.08).  

The investigators noted that common treatment targets for the prevention of post-diagnostic violence include criminality and victimization. They also argue that the treatment of positive symptoms should receive greater emphasis in individuals without a history of pre-diagnostic violence.

Reference

Hachtel H, Harries C, Luebbers S, Ogloff JRP. Violent offending is schizophrenia spectrum disorders preceding and following diagnosis [published online March 15, 2018]. Aust N Z J Psychiatry. 2018. doi:10.1177/0004867418763103