Thursday, March 30, 2023

Likely and Unlikely Causes of Mass Shootings


     

The pace of mass shootings and school shootings in the United States continues unabated at this time. I am writing this like I have written many posts in the past – a few days after a mass shooting in a school.  I just heard a news reports saying that this was the 167th school shooting since Columbine on April 20, 1999.  NPR posted a story saying that there is a shooting or a potential for shooting in schools every day (1) – based either on a gun discharge of someone brandishing a firearm in school. They reference the K-12 School Shooting Database stating that this is the 39th incident this year that involved gunfire on school grounds.

The media descriptions of the current incident follow much of the coverage in the past about unclear motive, shocking circumstances, unpredictability, questions of an “emotional disorder” and counseling, and the devastating impact on families and the community. I saw a forensic psychiatrist interviewed speculating on the aggressive dynamics based on the detail that the shooter recently disclosed a transsexual orientation.  A clergyman was interviewed and suggested the shooter was really looking for the school minister who was providing counseling.  One of the shooter’s fiends was interviewed.  She was contacted immediately prior to the incident and promptly notified authorities – but by then it was too late. The video of the SWAT team running through the hallways and eventually running toward gunfire and killing the shooter keeps playing.  In some cases that video is compared directly to the Uvalde, Texas video  and comments are made about this is a much better example of how law enforcement should respond. I saw some of these reports where they put up the response time on the screen.  

There are the usual expressions of “enough is enough” and “we don’t send our kids to school for this to happen.”  Republican Representative Tim Burchett came right out and said what most people were thinking: “ We’re not gonna fix it….” But then to make it more palatable he added: “criminals are gonna be criminals.”  He thought we needed a “revival” to “change peoples’ hearts in this country.” Later he disclosed he was home schooling his daughter (3).

I am already on record on this blog writing about the real cause of mass shootings and gun violence in general and it is the politics of gun extremism.  The Republican party has figured out that gun extremism works for them along with several other easily demagogued social issues like abortion, voter suppression, education, anti-science, anti-climate change, and more recently “wokeism”. That has led to a series of initiatives to drastically reduce gun regulations.  There has been an undeniable increase in deaths due to gun violence.  Mass shootings, suicide, homicide, and accidental deaths are all routinely ignored as calls for regulations that were effective for decades until Republican advocates rolled them back – even though gun regulations in the past were never a problem.

The typical rhetoric used is a gun extremist interpretation of the Second Amendment.  In the case of voters, it was the usual emotional appeal that “they” were coming to take their guns.  Anyone familiar with the distribution of guns in the United states realizes this is an impossibility, but it is a rallying point for emotional rather than rational appeals.  In recent years we have seen the rhetoric extended to mental illness as a cause of mass shootings.  There is some confluence with antipsychiatry factions who falsely equate psychiatry with the pharmaceutical industry and suggest that antidepressant drugs cause the mass shooting phenomena.  This post will provide clear evidence to the contrary.

On the issue of common psychiatric disorders in comparing the countries that utilize the most antidepressant prescriptions – the prevalence of those disorders is consistent among the United States and the other countries at the top of the list.  These disorders include depression, anxiety disorders, and substance use disorders – conditions that antidepressants are all commonly prescribed for. English speaking and European countries had similar prevalence (4) with possibly lower prevalence in Asia. There are similar variations in the estimated prevalence of schizophrenia and mood disorders in different areas of the world (5, 6).  

A good summary document on the research about mental illness and mass shooting incidents is available from the Treatment Advocacy Center (10).  They summarize the results of several studies as indicating that at least one third of the perpetrators had "serious untreated mental illness."  Their review is remarkable for a wide range of methodologies and selection biases that probably overestimates the number of cases of severe mental illness in mass shootings.  Smaller sample sizes generally showed a greater number of cases of severe mental illness.  In the case of a study by Stone (11) he found that 32% of 228 mass killers had severe mental illness but during the sampling period there were 1,000 incidents.  The variation is often considered due to methodological differences in the surveys but as previously illustrated– even significant differences in incidence and prevalence of these disorders is unlikely to account for the huge differences in gun deaths between the USA and other countries.  The main difference is that people with the same mental illnesses have much easier gun access in the US.

Several studies of people involved as shooters have shown that some of them have psychiatric diagnoses and in some cases they are being treated by psychiatrists.  Some are prescribed medications but the toxicology at the time of the incident is typically not available. In a related study of murder-suicide by the New York City Medical Examiner’s office that of 127 cases over a 9-year period only 3 (2.4%) were taking antidepressants (7).  Two were taking amitriptyline and 1 was taking sertraline. The authors made the point that antidepressant use in this case series was much lower than the expected population rate.  In a series of 27 elderly men who killed their spouse and then died by suicide – more disease conditions and depression were seen as possible predisposing factors – but none tested positive for antidepressants (8).  When considering the prescribing of antidepressants in general,  epidemiological studies suggest that most of these medications are prescribed by non-psychiatrists. With the proliferation of non-physician prescribers, managed care strategies designed to accelerate antidepressant prescribing based on limited assessments, and widely advertised televisit prescribing it is likely that gap between psychiatrist and other prescribers has increased substantially and will continue to grow.

The argument has been made that people become agitated, suicidal, and homicidal on antidepressants. This is a recurrent theme that is often related to medicolegal considerations, criticism of the pharmaceutical industry, and psychiatric criticism.  There is often a suggested scenario of the antidepressants (especially selective serotonin reuptake inhibitors or SSRIs) causing agitation or activation making suicidal or aggressive behavior more likely.  After reviewing the existing evidence the FDA has placed a black box warning for suicidality in "children, adolescents, and young adults".  There are also warning and counseling bullet points on clinical worsening as evidence by: "emergence of anxiety, agitation, panic attacks, insomnia, irritability, hostility, aggressiveness, impulsivity, akathisia (psychomotor restlessness), hypomania, mania, other unusual changes in behavior, worsening of depression, and suicidal ideation, especially early during antidepressant treatment and when the dose is adjusted up or down".  Standard medical and psychiatric practice advises the patient of these potential risks and what the plan should be if they occur.  In 35 years of clinical practice my observations were that these symptoms were rare and most likely to occur if an antidepressant was discontinued and the patient experienced significant sleep disturbance. The patients I treated with severe aggressive behavior were generally untreated for psychiatric disorders and often had substance use disorders.  A recommendation I have not seen is that all of these incidents should be studied from a prospective comprehensive psychiatric standpoint as they occur with no selection bias.  That study should include toxicology, detailed collateral information, analysis of available medical records, and post mortem analysis if relevant.

In choosing a reference (9) for international comparison of mass shooting phenomenon it is important to consider how the database is constructed. In choosing reference 9, the author described a clear rationale and methodology.  The basic criteria include an incident where there are at least 4 shooting deaths and the shooter is acting alone and not due to criminal or terroristic motivations. Since mass shootings in the US have been motivated by neither – there would be no equivalent comparison with incidents in the US. The author also compares the US to the 35 United Nations definition economically developed countries (see Supplement 1). The time frame of 1998-2019 was chosen.  On that basis half of the countries did not have a single mass shooting incident, ten had more than one, five had more than 20 fatalities, and the US had 12 times as many incidents as the country with the second most mass shootings. Much greater detail is included in the original reference.

I prepared two reference tables based on this data (click on either table for a better view).  The graphic at the top of this page does not include suicide and homicide rates for each country.  The table below includes both of these rates.  Data sources are referenced in the tables.  

 


The countries are arranged by defined daily doses (DDD) of antidepressant medications.  DDD is a World Health Organization (WHO) defined metric for medication utilization. It looks at the total amount of a defined class of medication using the Anatomic Therapeutic Chemical (ATC) classification based on the usual prescribed dose of medication. In that system antidepressants are listed as a class.  US data are highlighted in the table because they represent the focus of this post.

What are some likely and unlikely observations from the Table.  First, it is unlikely that antidepressant prescriptions are a proximate cause of mass shootings.  The countries bracketing the US in antidepressant utilization (Iceland and Portugal) each had no mass shooting during the period of interest (1999-2018).  Second, gun availability stands out as an obvious factor in mass shootings, gun related suicides, and gun related homicides.  Third, gun availability in the US (120.5 firearms per 100 person) nearly equals gun availability in every other country in the table (128.4 firearms per 100 persons).  Fourth, no country had homicide rates similar to the US, but 3 of the countries had similar suicide rates but much lower rates of gun suicides. The reference study looks at locations, relationships, and firearms as relevant points but no comments on mental illness or toxicology at the time of the incident. The author also points out that in many countries mass shootings trigger government intervention focused on decreasing the likelihood of future shootings.  Except for a time limited assault rifle ban that does not happen in the United States.  The gun regulatory landscape is headed in the opposite direction with a movement to permitless access to handguns.

In summary, the gun violence landscape in the United States is bleak. Despite rationalizations that this is really a mental illness or mental illness treatment problem there is no real supporting evidence, since the distribution of mental illnesses in the US is the same as comparable countries with no to few mass shootings. There is low quality evidence that mental illness may be a factor in 15-30% of incidents - but the only way to explain why that is a factor is those people have much easier access to firearms.  The overwhelming evidence is that this is a problem of gun extremism, gun access, and sociocultural factors like subcultural acceptable violence, media notoriety, and politically reinforced messaging about gun use. The only way to address the problem based on international examples is to decrease gun access.  That is unlikely as long as one major party and their appointed judges need to activate their base with false messaging and flood the country with easy to access firearms.  They bear the ultimate responsibility.

George Dawson, MD, DFAPA

 

Supplementary 1:  UN Classified Developed Countries (total of 36) for reference 3 in Table and reference 9 below:  Australia, Austria, Belgium, Bulgaria, Canada, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Japan, Latvia, Lithuania, Luxembourg, Malta, Netherlands, New Zealand, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, United Kingdom, and the United States.

 

 References:

1:   Florido A, Summers J. By one measure, the U.S. has had a shooting on school grounds almost every day.  https://www.npr.org/2023/03/28/1166630346/by-one-measure-the-u-s-has-had-a-shooting-on-school-grounds-almost-every-day

2:  K-12 School Shooting Database:  https://k12ssdb.org/all-shootings

3:  Winter J.  After the Nashville shooting a faithless remedy for gun violence. New Yorker.  Amrch 29, 2023:  https://www.newyorker.com/news/daily-comment/after-the-nashville-school-shooting-a-faithless-remedy-for-gun-violence

4:  Steel Z, Marnane C, Iranpour C, Chey T, Jackson JW, Patel V, Silove D. The global prevalence of common mental disorders: a systematic review and meta-analysis 1980-2013. Int J Epidemiol. 2014 Apr;43(2):476-93. doi: 10.1093/ije/dyu038. Epub 2014 Mar 19. PMID: 24648481; PMCID: PMC3997379.

5:  Goldner EM, Hsu L, Waraich P, Somers JM. Prevalence and incidence studies of schizophrenic disorders: a systematic review of the literature. Can J Psychiatry. 2002 Nov;47(9):833-43. doi: 10.1177/070674370204700904. PMID: 12500753.

6:  Waraich P, Goldner EM, Somers JM, Hsu L. Prevalence and incidence studies of mood disorders: a systematic review of the literature. Can J Psychiatry. 2004 Feb;49(2):124-38. doi: 10.1177/070674370404900208. PMID: 15065747.

7:  Tardiff K, Marzuk PM, Leon AC. Role of antidepressants in murder and suicide. Am J Psychiatry. 2002 Jul;159(7):1248-9. doi: 10.1176/appi.ajp.159.7.1248. PMID: 12091219.

8:  Malphurs JE, Eisdorfer C, Cohen D. A comparison of antecedents of homicide-suicide and suicide in older married men. Am J Geriatr Psychiatry. 2001 Winter;9(1):49-57. PMID: 11156752.

9:  Silva JR. Global mass shootings: Comparing the United States against developed and developing countries. International Journal of Comparative and Applied Criminal Justice. 2022 Mar 21:1-24.

10: Treatment Advocacy Center.  Serious Mental Illness and Mass Homicide. June 2018,  https://www.treatmentadvocacycenter.org/key-issues/violence/3626-serious-mental-illness-and-mass-homicide

11:  Stone, M. F. (2015). Mass murder, mental illness, and men. Violence and Gender. 2015; 2, 51-86.

 

 

 

No comments:

Post a Comment