Researchers identify risk factors that predict violence in adults with mental illness

RESEARCH TRIANGLE PARK, NC— Three risk factors that make adults with mental illness more likely to engage in violent behavior have been identified by researchers from RTI International, North Carolina State University, Duke University and Arizona State University. 

The findings give mental health professionals and others working with adults with mental illness a suite of characteristics they can use as potential warning signs, allowing them to intervene and hopefully prevent violent behavior. The study was published in the journal Psychiatric Services and funded as part of a grant from the National Institute of Mental Health. 

"Our earlier work found that adults with mental illness are more likely to be victims of violence than perpetrators – and that is especially relevant to this new study," says Sarah Desmarais, an associate professor of psychology at North Carolina State University and co-author of a paper describing the work. "One of the new findings is that people with mental illness who have been victims of violence in the past six months are more likely to engage in future violent behavior themselves."

Researchers compiled a database of 4,480 adults with mental illnesses, including schizophrenia, bipolar disorder, and depression, who had answered questions about both committing violence and being victims of violence in the previous six months. The database drew from five earlier studies that focused on issues ranging from antipsychotic medications to treatment approaches. Those studies had different research goals, but all asked identical questions related to violence and victimization.

Researchers assessed the data to determine which behaviors, events and characteristics were most predictive of violent behavior over a six-month period. Violent behavior, in this context, ranged from pushing and shoving to sexual assault and assault with a deadly weapon.

The study found three risk factors that were predictive of violent behavior: if an individual is currently using alcohol; if an individual has engaged in violent behavior over the past six months; and if an individual has been a victim of violence within the past six months.

"We found that these risk factors were predictive even when we accounted for age, sex, race, mental illness diagnosis and other clinical characteristics," Desmarais says.

In contrast, the researchers found that current drug use was not predictive of violent behavior, when age, sex, race, mental illness diagnosis, and other clinical characteristics were considered.

"Finding ways to incorporate these risk factors into routine and ongoing risk assessment and risk management practices may help those working in clinical settings to better manage violence risk among adults with mental illness," said Richard Van Dorn, Ph.D., senior mental health services researcher at RTI and the project's principal investigator. "It's important that we understand the relationship between violence and victimization and find ways to both reduce both in order to make communities safer."