Understanding Severe Mental Illness

When a tragedy occurs like the shooting in Tucson this past weekend, all of us seek an explanation. While there remain many questions, a leading hypothesis is that the suspect has a serious mental illness (SMI), such as schizophrenia. The topic of violence and mental illness is never an easy discussion: with issues such as stigma, incarceration, public safety, and involuntary treatment in the mix. There is a legitimate concern that talking about violence and mental illness in the same sentence increases the likelihood that people with serious illness will be further marginalized and less likely to receive appropriate care. But tragic events, whether at a Safeway in Tucson or a classroom at Virginia Tech, require us to address this uncomfortable subject with the science available.

Is violence more common in people with SMI? Yes, during an episode of psychosis, especially psychosis associated with paranoia and so-called “command hallucinations”, the risk of violence is increased. People with SMI are up to three times more likely to be violent and when associated with substance abuse disorders, the risk may increase much further.ⁱ But, mental illness contributes very little to the overall rate of violence in the community. Most people with SMI are not violent, and most violent acts are not committed by people with SMI. In fact, people with SMI are actually at higher risk of being victims of violence than perpetrators. Teplin et al found that those with SMI are 11 times more likely to be victims of violent crime than the general population.ⁱⁱ

The most common form of violence associated with mental illness is not against others, but rather, against oneself. In 2007, the most recent year for which we have statistics, there were almost 35,000 suicides, nearly twice the rate of homicides. Suicide is the 10th leading cause of death in the United States.ⁱⁱⁱ Although it is not possible to know what prompted every suicide, it is safe to say that unrecognized, untreated mental illness is a leading culprit.

Treatment may be the key to reducing the risk of violence, whether that violence is self-directed or directed at others. Research has suggested that those with schizophrenia whose psychotic symptoms are controlled are no more violent than those without SMI.^iv It’s likely that treatment not only helps ease the symptoms of mental illness, but also curbs the potential for violence as well.

As we learn more about the circumstances surrounding the tragedy in Tucson, we should be working harder to ensure people with SMI receive the care they need. Early intervention offers the best hope to prevent more tragedies in the future.

For more information on SMI and other mental health statistics, please visit NIMH’s Statistics page.

Information on coping with trauma.

ⁱSwanson JW. Mental disorder, substance abuse, and community violence: an epidemiological approach. In: Monahan J, Steadman HJ, eds. Violence and mental disorder: developments in risk assessment. Chicago: University of Chicago Press, 1994:101-36.

ⁱⁱTeplin et al. Crime victimization in adults with severe mental illness. Archives of General Psychiatry.2005 Aug. 62. 911-921.

ⁱⁱⁱCenters for Disease Control and Prevention, National Center for Injury Prevention and Control. Web-based Injury Statistics Query and Reporting System (WISQARS). www.cdc.gov/ncipc/wisqarsExternal Link: Please review our disclaimer..

^ivSteadman HJ, Mulvey EP, Monahan J, et al. Violence by people discharged from acute psychiatric inpatient facilities and by others in the same neighborhoods. Arch Gen Psychiatry 1998;55:393-401.