On October 1, 2017, a devastating mass shooting at the Route 91 Harvest Music Festival in Las Vegas left 60 people dead and 867 injured. A recent study published in JAMA Network Open has revealed that even four years after this tragic event, a significant number of the survivors and witnesses continue to suffer from severe mental health issues. Specifically, nearly half of the concertgoers surveyed reported experiencing major depressive episodes in the past year, while over 63% faced symptoms of post-traumatic stress disorder (PTSD).
Mass violence incidents, like the 2017 Las Vegas shooting, often leave deep psychological scars. Prior research has established that survivors and witnesses of such tragedies can experience long-lasting mental health problems, including depression and PTSD. However, the specific long-term impacts on those affected by the Las Vegas event had not been thoroughly investigated until now.
The study included adults who were either physically present at the 2017 Route 91 Harvest Music Festival during the shooting or were closely connected to someone who was harmed or killed during the event. Participants were identified from a list of individuals eligible to receive services from the Vegas Strong Resiliency Center, which is supported by the U.S. Department of Justice Office for Victims of Crime.
Data collection occurred between September and November 2021 through a self-administered online survey. The survey was designed to be accessible and straightforward to encourage maximum participation and accurate reporting of sensitive information. To participate, individuals had to provide written informed consent, following the ethical guidelines approved by the Institutional Review Boards of Boston University and the Medical University of South Carolina.
The survey included a modified version of the National Women’s Study Depression module to assess major depressive episodes and the National Stressful Events Survey PTSD module to evaluate symptoms of post-traumatic stress disorder. These instruments are specifically tailored to detect and quantify the severity of depression and PTSD symptoms, respectively, and have been validated in previous research focused on similar traumatic events.
Out of the 177 participants who completed the survey, 49.2% reported experiencing major depressive episodes in the past year, and 63.3% reported symptoms consistent with PTSD. These rates are notably higher than those typically found in the general population, underscoring the severe psychological aftermath of mass violence incidents. The study’s findings are particularly alarming given the passage of time since the event, suggesting that the effects of such traumas can persist long after the incident itself.
Further analysis revealed specific factors that exacerbated these mental health challenges. Notably, physical injuries sustained during the incident significantly increased the likelihood of experiencing both depressive episodes and PTSD. Participants who were physically injured were 36% more likely to have experienced major depressive episodes and 32% more likely to have suffered from PTSD compared to those who were not injured.
“Our findings reveal the long-lasting impact of gun violence on witnesses and survivors, with many still grappling with severe mental health issues years after the Las Vegas shooting,” said first author on the paper, Mohammed Abba-Aji, a research fellow at the Boston University School of Public Health. “This underscores the unique and ongoing challenge America faces with mass violence and its aftermath. This crisis calls for a national response to not only address but to also prevent the enduring trauma inflicted on our communities.”
Another critical factor identified was the level of social support received by individuals following the incident. The study found that adequate social support was associated with a significantly reduced risk of both major depressive episodes and PTSD. Specifically, those with low social support had a higher likelihood of these mental health issues, with figures indicating nearly a 50% increased risk compared to those who received adequate support. This finding highlights the importance of community and interpersonal support systems in mitigating the psychological effects of trauma.
“The fact that such a high percentage of these mass violence victims still had PTSD and depression four years later is disturbing and demonstrates a continuing need for effective, trauma-informed mental health services,” said Dean Kilpatrick, a distinguished professor at the Medical University of South Carolina and principal investigator on the project. “There is also a need for larger studies with longer follow-up of these survivors to see if these problems persist.”
Overall, the study painted a stark picture of the long-lasting and severe impact of mass shootings on individual mental health. It emphasized the need for ongoing support and intervention for survivors of such incidents, pointing to the importance of both immediate and sustained mental health care.
“Our study adds to the evidence around the devastating societal impact of mass shootings and the need to advocate for policies to prevent them” said study co-author Salma Abdalla, an assistant professor of global health at the Boston University School of Public Health. “Moreover, the findings underline the necessity for ongoing mental health care, especially among people who experience physical injuries and lack of social support. The results highlight the urgent need for our health systems to prioritize long-term care strategies for trauma survivors, ensuring they receive the necessary support to effectively navigate their recovery journeys.”
The study, “Prevalence and Risk Factors of Depression and Posttraumatic Stress Disorder After a Mass Shooting,” was authored by Mohammed Abba-Aji, Angela Moreland, Salma M. Abdalla, Caitlin Rancher, Sandro Galea, Faraday Davies, and Dean G. Kilpatrick.
