Study finds adolescent suicidal behavior is significantly associated with externalizing behaviors and violence exposure

December 2, 2024 -- Suicide remains a leading cause of death among adolescents, according to a  new study by Columbia University Mailman School of Public Health. Among U.S. high school students’ suicidal behavior is significantly associated with externalizing behaviors and violence exposure. This is the first study to assess this association at the state level. The findings appear in the American Journal of Preventive Medicine.

Although access to firearms and other weapon use contribute to suicide risk, the underlying risk for, and correlates of, firearm use among U.S. adolescents is understudied. A cross-sectional study using data from 1991 to 2021 on 234,588 adolescents from the Youth Risk Behavior Survey examined the associations between externalizing behaviors, violence exposure, firearm carrying, and suicidal behavior to provide an assessment of the ways in which broader violence risk factors may increase the risk for injurious self-harm.

Externalizing behaviors are characterized by aggressive and disruptive behaviors that can be harmful to others or the social environment. Examples of externalizing behaviors and violence expression are threatening others with a weapon, starting a physical fight, and committing sexual violence.

"We found significant associations between suicidal behavior and externalizing behaviors and violence exposure, with higher magnitudes of associations among those with a suicide attempt requiring medical treatment,” said Victoria A. Joseph, MPH, Department of Epidemiology, Columbia Mailman School of Public Health, and first author. “The association between externalizing behaviors and violence exposure and injurious suicide attempt also varied over time and by sex."

Firearm-based suicide rates have increased among adolescents in recent years, suggesting a growing urgency to examine dynamics surrounding firearms and their role pertaining to suicidal behavior. Access to firearms and suicide rates in the US vary by state.

"Suicide deaths are more prevalent among individuals who live in rural areas due in part to firearm access, isolation, and limited access to mental health services. State-level variations of suicide rates are heavily driven by suicide deaths involving firearms," Joseph explains.

The study's researchers evaluated trends from data available from 16 states (ID, IL, IA, LA, MI, MS, MT, NE, NH, NM, NY, OK, PA, UT, VA, and WV) on carrying a gun or other weapon. They found that among adolescents with an injurious suicide attempt in 2021, state-level differences in weapon access emerged.

“Although the prevalence of suicide involving firearms is higher in the West, surprising trends emerged such as low prevalence of weapon access among those with an injurious suicide attempt in gun ownership states such as Montana and high prevalence in states with low gun ownership such as New York. It should be noted that sparse data at the state level hindered the assessment of trends over time in every state,” Joseph explains,. Due to variations in suicide rates, gun laws and weapon access in the U.S., state-level assessments of suicide risk and interventions are essential.”

Lead investigator of the study Katherine M. Keyes, PhD, professor of Epidemiology, concludes, “Firearm injury is a leading cause of morbidity and mortality among young people in the United States, including through suicidal behavior. Youth who carry weapons and have higher risks of engaging in physical violence also have a higher risk of self-inflicted violence, underscoring the need for stronger firearm protections to protect youth health.”

A co-author of the study “Externalizing Behaviors/Violence Exposure and Suicide Among U.S. Adolescents (https://doi.org/10.1016/j.amepre.2024.08.014) is Noah T. Kreski, Columbia Mailman School.

The study was supported by NIH grant R01-DA048853.

Columbia University Mailman School of Public Health

Founded in 1922, the Columbia University Mailman School of Public Health pursues an agenda of research, education, and service to address the critical and complex public health issues affecting New Yorkers, the nation and the world. The Columbia Mailman School is the third largest recipient of NIH grants among schools of public health. Its nearly 300 multi-disciplinary faculty members work in more than 100 countries around the world, addressing such issues as preventing infectious and chronic diseases, environmental health, maternal and child health, health policy, climate change and health, and public health preparedness. It is a leader in public health education with more than 1,300 graduate students from 55 nations pursuing a variety of master’s and doctoral degree programs. The Columbia Mailman School is also home to numerous world-renowned research centers, including ICAP and the Center for Infection and Immunity. For more information, please visit www.mailman.columbia.edu.