The work was done by researchers at North Carolina State University; RTI International; the University of California, Davis; Simon Fraser University; and Duke University.
“We hear about the link between violence and mental illness in the news, and we wanted to look not only at the notion that the mentally ill are a danger to others, but the possibility that they are also in danger,” says Dr. Sarah Desmarais, an assistant professor of psychology at NC State and lead author of a paper describing the work.
The researchers compiled a database of 4,480 mentally ill adults 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.
The researchers found that 23.9 percent of the study participants had committed a violent act within the previous six months. The majority of those acts – 63.5 percent – were committed in residential settings, not in public. Only 2.6 percent of the violent acts were committed in school or workplace settings.
The researchers found that a significantly higher percentage of participants – 30.9 percent – had been victims of violence in the same time period. And of those who said they were victimized, 43.7 percent said they’d been victimized on multiple occasions.
“We also found that participants who had been victims of violence were 11 times more likely to commit violence,” Desmarais says. “This highlights the need for more robust public health interventions that are focused on violence. It shouldn’t just be about preventing adults with mental illness from committing violent acts, it should also be about protecting those at risk of being victimized.
“For one thing, it’s the right thing to do,” Desmarais adds. “In addition, while correlation is not necessarily causation, preventing violence against the mentally ill may drive down instances of violence committed by the mentally ill.”
The paper, “Community Violence Perpetration and Victimization Among Adults With Mental Illnesses,” is published online in the American Journal of Public Health. The paper was co-authored by Dr. Richard Van Dorn of RTI International; Kiersten Johnson, a graduate student at NC State; Dr. Kevin Grimm of University of California, Davis; Dr. Kevin Douglas of Simon Fraser University; and Dr. Marvin Swartz of Duke University.
The study was supported by the National Institute for Mental Health under grant number R01MH093426 to Van Dorn.
Note to Editors: The study abstract follows.
“Community Violence Perpetration and Victimization Among Adults With Mental Illnesses”
Authors: Sarah L. Desmarais and Kiersten L. Johnson, North Carolina State University; Richard A. Van Dorn, RTI International; Kevin J. Grimm, University of California, Davis; Kevin S. Douglas, Simon Fraser University; and Marvin S. Swartz, Duke University
Published: online February 2014, American Journal of Public Health
Abstract: Objectives. In a large heterogeneous sample of adults with mental illnesses, we examined the 6-month prevalence and nature of community violence perpetration and victimization, as well as associations between these outcomes. Methods. Baseline data were pooled from 5 studies of adults with mental illnesses from across the United States (n=4480); the studies took place from 1992 to 2007. The MacArthur Community Violence Screening Instrument was administered to all participants. Results. Prevalence of perpetration ranged from 11.0% to 43.4% across studies, with approximately one quarter (23.9%) of participants reporting violence. Prevalence of victimization was higher overall (30.9%), ranging from 17.0% to 56.6% across studies. Most violence (63.5%) was perpetrated in residential settings. The prevalence of violence-related physical injury was approximately 1 in 10 overall and 1 in 3 for those involved in violent incidents. There were strong associations between perpetration and victimization. Conclusions. Results provided further evidence that adults with mental illnesses experienced violent outcomes at high rates, and that they were more likely to be victims than perpetrators of community violence. There is a critical need for public health interventions designed to reduce violence in this vulnerable population.