Mental Illness and Violence: A Link?
Mental Illness Alone Doesn't Predict Violence, but Substance Abuse Increases Risk for Mentally Ill, Study Shows
Mental Illness & Violence: Results
In all, 2.9% of participants said they had been violent in the time between the first and second interviews.
When Elbogen evaluated the possible associations between mental illness, violence, and other factors, having a mental illness alone did not predict violence, but having a mental illness and a substance abuse problem did increase the risk of violence.
The risk was increased even more if the person had mental illness, substance abuse problems, and a history of violence.
For instance, when Elbogen looked at those who only had a severe mental illness, 2.4% had been violent. But when he looked at those with major depression and substance abuse or dependence, 6.47% had been violent.
When he looked at those with schizophrenia, 5.15% reported violent behavior in the time period between the interviews. But when a person with schizophrenia also had substance abuse or dependence problems, 12.66% reported violent behavior in the time between the interviews.
The highest risk for violence was found in those who had mental illness, a substance abuse problem, and a history of violence. These participants had 10 times the risk of violence than those who only had mental illness.
Other factors that predicted violent behavior included a history of juvenile detention or physical abuse, having seen parental fighting, a recent divorce, unemployment, or being victimized themselves. Being younger, male, and low-income also boosted the chance of violence.
"There is a relationship [between mental illness and violence] but it's much weaker than most people think," he tells WebMD.
"I think a lot of people think mental illness is the usual cause if not the foremost cause of violence," Elbogen says, citing a survey in which 75% of respondents said they considered people with mental illness as dangerous.
But his study concludes that “the findings say mental illness is relevant and you can see that throughout the data. But it's not really one of the foremost causes of violent behavior [by itself] in our society."
Mental Illness & Violence: Second Opinions
Experts who reviewed the paper for WebMD say they hope the new research may change mistaken perceptions toward those who are mentally ill.