This is a current (6:30pm Pacific Time, December 6, 2007) headline on CNN:

“State official: Shooter placed in mental health facility 5 years ago“.

Yahoo! news reports “Omaha gunman freed from centers, homes“. MSNBC leaves it at “Mourners light candles for Omaha mall victims” and the New York Times states “Details of Omaha Shooting Emerge”.

We cannot contest the truth within CNN’s headline: Yes, the public record indicates that the young man received (both in the past and recently) mental health treatment. Placing this information within the headline, however, overemphasizes this fact. Though not explicitly stated, the implicit message is “the reason why this young man shot all of those people is because he was mentally ill”. This information can be further distorted such that people then think “mentally ill people are violent”. The media communicated similar messages earlier this year following the Virginia Tech shootings and thus, one might then suppose “all mentally ill people are violent”.

Stigma increases.

So? Is it really true that people with psychiatric diagnoses are “all” violent? How about just “more likely” to be violent? By how much?

Is all of this media attention on “mental health” warranted?

What evidence is available?

One paper (”Violence by people discharged from acute psychiatric inpatient facilities and by others in the same neighborhoods“) compared people who were recently discharged from psychiatric facilities (the study group) and people who lived in the same neighborhoods as the study group. The study followed everyone for one year. For those who did not use any illicit substances, the rate of violence did not differ significantly between the two groups. For those people who did use illicit substances, the rate of violence increased in both groups and was higher in those with a psychiatric diagnosis. Most of the violence was directed towards family and friends. Of note, most of the violence from the study group occurred within the first ten weeks following discharge from the hospital (though it is also true that people “disappeared” from the study as it progressed…). There was also something suboptimal about the statistics (a field which is definitely not my forte)… though that is often said about many, many studies.

So one might conclude from this study that substance abuse/dependence increases the risk of violence in all people, though a bit more in people with a psychiatric diagnosis, particularly in the period immediately following discharge from hospitalization.

Another paper reviewed data from the National Comorbidity Survey (a mental health survey that involved thousands of people—this is the document that came up with the statistic that nearly 50% of people experience a mental disorder in their lifetime…). This data relied upon self-report. The paper concluded that

People with 12-month diagnoses of anxiety disorders, dysthymia and major depression were three to four times more likely to admit violent behaviors than those with no disorders. People with bipolar disorder or drug and alcohol abuse were eight times more likely to report violent behaviors. People with co-occurring non-substance and substance abuse disorders were more likely to report violence than those with only non-abuse disorders.

The authors also state in the abstract (I do not have access to the paper myself) that ethnicity and gender are better predictors of violence than psychiatric diagnoses (which opens up another can of worms…).

What does this information mean? That people with psychiatric diagnoses are more likely to share this information? Are we to assume that everyone was telling the truth? Was there any collateral information available?

Another paper appeared in the New England Journal of Medicine (by Richard Friedman, who I referred to a couple entries back) that also asked the question I write of now. He, too, reviews a few studies, including another large, epidemiological study (it looks like from a book?), which concluded that people with diagnoses of schizophrenia, major depression, and bipolar disorder were twice to three times as likely to assault someone as compared to those who do not have a psychiatric diagnosis. (He also comments about the increased likelihood of violence in those individuals using illicit substances.) However, he then states that the prevalence of mental disorders is very low in the population and thus contributes very little to the absolute amount of violence in a population. He pithily finishes the article with “most people who are violent are not mentally ill, and most people who are mentally ill are not violent.”

I don’t know just how much “strength” we can attribute to what data is available. There seem to be some associations, but there certainly is insufficient evidence to support the idea that all people with psychiatric diagnoses are dangerously violent.

It is both unfair and unfortunate that some major media insist on advertising in bold, large-point font that perpetrators of violence are mentally ill. Such disproportionate attention suggests causation when none exists. Do headlines ever read “SHOOTER DID NOT HAVE A MENTAL ILLNESS”? Or “GUNMAN NEVER RECEIVED MENTAL HEALTH SERVICES”?

Why not?

I do not mean to minimize the sorrow of the citizens of Omaha. We all wish for a reason for this violence—we want to assign responsibility to someone or something. A psychiatric diagnosis or history, however, is not always—and, in fact, is very rarely—to blame.