Changes in Rates of Suicide by Mass Shooters, 1980-2019.

OBJECTIVE: The rate of worldwide mass shootings increased almost 400% over the last 40 years. About 30% are followed by the perpetrator's fatal or nonfatal suicide attempt. METHOD: We examined the rate of fatal and nonfatal attempts among 528 mass shooters over the last 40 years and their relationship to detected mental illness to better understand this specific context of suicide. We collected information on U.S.-based, personal-cause mass murders that involved one or more firearms, from online sources. RESULTS: A greater proportion of mass shooters from 2000 to 2019 took or attempted to take their own lives (40.5%) compared with those from 1980 to 1999 (23.2%, p < 0.001). More than double the proportion of perpetrators who made a fatal or nonfatal suicide attempt had a history of non-psychotic psychiatric/neurologic symptoms (38.9%), compared with perpetrators who did not make a fatal or nonfatal suicide attempt (18.1%; p < 0.001). Among mass shooters who made fatal or nonfatal suicide attempts, 77 of 175 (44%) did not have any recorded psychiatric, neurologic, or substance use condition. Of the 98 mass shooters who made fatal or non-fatal suicide attempts and had a psychiatric, substance use, or neurologic condition, 41 had depressive disorders. CONCLUSION: It is possible that a lack of information about the perpetrators' mental health or suicidal ideation led to an underestimation of their prevalence. These data suggest that suicide associated with mass shootings may represent a specific context for suicide, and approaches such as psychological autopsy can help to ascertain when psychiatric illness mediates the relationship between mass shootings and suicide.

We examined 528 mass shootings.A greater proportion of mass shooters from 2000-2019 made a fatal or nonfatal suicide attempt (123/304, 40.5%) compared with mass shooters from 1980-1999 (52/224, 23.2%), χ2 = 17.3, p<.001.More than double the proportion of perpetrators who made a fatal or nonfatal suicide attempt had a history of non-psychotic psychiatric/neurologic symptoms (38.9%), compared with those who did not (18.1%; p < 0.001).Among mass shooters who made a fatal or nonfatal suicide attempt, 77 of 175 (44%) did not have any recorded psychiatric, neurologic, or substance use condition. However, it is possible that a lack of information about the perpetrators' mental health or suicidal ideation led to an underestimation of their prevalence.These results suggest that perpetrators may have considered suicide a potential outcome of such an event, and/or that the perpetrators' high levels of aggression and anger, accompanied by an impaired capacity for restraint, resulted in homicide followed by suicidal behavior.Psychological autopsies can clarify the role of psychiatric illness and more extreme aggressive traits in homicide-suicide instances of mass shootings.

An Analysis of Motivating Factors in 1,725 Worldwide Cases of Mass Murder Between 1900-2019.

Mass murder, particularly mass shootings, constitutes a major, growing public health concern. Specific motivations for these acts are not well understood, often overattributed to severe mental illness. Identifying diverse factors motivating mass murders may facilitate prevention. We examined 1,725 global mass murders from 1900-2019, publicly described in English in print or online. We empirically categorized each into one of ten categories reflecting reported primary motivating factors, which were analyzed across mass murderers generally, as well as between U.S- and non-U.S.-based mass-shooters. Psychosis or disorganization related to mental illness were infrequently motivational factors (166; 9.6%), and were significantly more associated with mass murder committed using methods other than firearms. The vast majority (998, 57.86%) of incidents were impulsive and emotionally-driven, following adverse life circumstances. Most mass murderers prompted by emotional upset were found to be driven by despair or extreme sadness over life events (161, 16.13% within the category); romantic rejection or loss, or severe jealousy (204, 20.44% within the category); some specific non-romantic grudge (212, 21.24% within the category); or explosive, overwhelming rage following a dispute (266, 26.65% within the category). Results suggest that policies seeking to prevent mass murder should focus on criminal history, as well as subacute emotional disturbances not associated with severe mental illness in individuals with poor coping skills who have recently experienced negative life events.

Victimology of Mass Shootings and Mass Murders Not Involving Firearms.

Most research to date has focused on perpetrators of mass murder incidents. Hence, there is little information on victims. We examined 973 mass murders that occurred in the United States between 1900 and 2019 resulting in 5,273 total fatalities and 4,498 nonfatal injuries for a total of 9,771 victims (on average 10 victims per incident). Approximately 64% of victims of mass murder were White individuals, 13% were Black individuals, 6% were Asian individuals, and 14% were Latinx individuals. Given the higher number of nonfatal injuries per non-firearm mass murder event (11.0 vs. 2.8, p < .001), the total number of victims was only 50% higher for mass shootings (5,855 victims) vs. non-firearm mass murder events (3,916 victims). Among the 421 incidents of mass murder in the United States since 2000, Black, Asian, and Native American individuals were overrepresented among victims of mass shootings compared with their representation in the general U.S. population, and White individuals were underrepresented (all p ≤ .002). Findings of racial/ethnic differences were similar among victims of mass murder committed with means other than firearms for Black, Asian, and White individuals. These findings highlight different areas of victimology within the context of these incidents.

Mass murders involving firearms and other methods in school, college, and university settings: Findings from the Columbia Mass Murder Database.

While mass murders involving academic settings, especially using firearms, are of grave, growing public concern, identifying consistent patterns to aid prevention has proved challenging. Although some characteristics, such as male sex, have been routinely associated with these events, another hypothesized risk factor, severe mental illness, has been less reliably predictive. We isolated cases of mass murder perpetrated at least in part at schools, colleges, and universities from the Columbia Mass Murder Database (CMDD) and categorized them by location (within or outside of the US), and whether firearms were used. Demographic similarities and differences between groups were analyzed statistically wherever possible. We examined 82 incidents of mass murder, by any means, involving academic settings. Nearly half of all incidents (47.6%), and most involving firearms (63.2%), were U.S.-based, whereas those not involving firearms largely occurred elsewhere (88.0%). Consistent with previous reports, perpetrators of mass shootings involving academic settings are primarily Caucasian (66.7%) and male (100%). Severe mental illness (i.e., psychosis) was absent in the majority of perpetrators (firearms: 80.7%; nonfirearms: 68.0%). About half (45.6%) of mass school shootings ended with the perpetrator's suicide. When present, psychotic symptoms are more associated with mass murders in academic settings involving means other than firearms. The question of whether perpetrators of such incidents may perceive their actions as a kind of final act might enhance policy development and/or how law enforcement intervenes.

Psychotic symptoms in mass shootings v. mass murders not involving firearms: findings from the Columbia mass murder database.

BACKGROUND: Mass shootings account for a small fraction of annual worldwide murders, yet disproportionately affect society and influence policy. Evidence suggesting a link between mass shootings and severe mental illness (i.e. involving psychosis) is often misrepresented, generating stigma. Thus, the actual prevalence constitutes a key public health concern. METHODS: We examined global personal-cause mass murders from 1900 to 2019, amassed by review of 14 785 murders publicly described in English in print or online, and collected information regarding perpetrator, demographics, legal history, drug use and alcohol misuse, and history of symptoms of psychiatric or neurologic illness using standardized methods. We distinguished whether firearms were or were not used, and, if so, the type (non-automatic v. semi- or fully-automatic). RESULTS: We identified 1315 mass murders, 65% of which involved firearms. Lifetime psychotic symptoms were noted among 11% of perpetrators, consistent with previous reports, including 18% of mass murderers who did not use firearms and 8% of those who did (χ2 = 28.0, p < 0.01). US-based mass shooters were more likely to have legal histories, use recreational drugs or misuse alcohol, or have histories of non-psychotic psychiatric or neurologic symptoms. US-based mass shooters with symptoms of any psychiatric or neurologic illness more frequently used semi-or fully-automatic firearms. CONCLUSIONS: These results suggest that policies aimed at preventing mass shootings by focusing on serious mental illness, characterized by psychotic symptoms, may have limited impact. Policies such as those targeting firearm access, recreational drug use and alcohol misuse, legal history, and non-psychotic psychopathology might yield more substantial results.

Thematic content of obsessive and compulsive symptoms and conversion to psychosis in a clinical high-risk cohort.

AIM: We sought to explore the complex phenomenological overlap between obsessive and compulsive symptoms (OCS), and attenuated positive symptoms among 156 young people at clinical high-risk (CHR) for psychosis. METHODS: In order to explore the hypothesis that OCS of an implausible nature might optimally predict future transition to syndromal psychosis, ideas associated with obsessive and compulsive experiences elicited by clinical measures were thematically categorized as "plausible" or "implausible." RESULTS: While OCS were found to be common in our CHR sample, we did not find that implausible OCS themes were predictive of conversion. CONCLUSION: Given the absence of qualitative differences between OCS and early psychotic symptoms, we propose that clinicians encountering adolescent or young adult patients with new-onset OCD or OCS in the past year should monitor such symptoms for a minimum of 2 years to assess for the possible emergence of psychosis.

Temporal relationship between onset of positive and negative symptoms in the course of attenuated psychotic illness.

Research in individuals at clinical high-risk (CHR) for psychosis has traditionally focused on the relationship between the severity of positive and negative symptoms and development of syndromal psychosis. In this study, we examined the temporal order of emergence of positive and negative symptoms in 116 CHR individuals who met criteria for the Attenuated Positive Symptom Syndrome defined in the Structured Interview for Psychosis-Risk Syndromes (SIPS). We found that positive symptoms emerged at a significantly younger age than negative symptoms with no significant differences between converters and non-converters. These findings may provide important information about the temporal phenomenology of CHR symptoms.