Non-suicidal self-injury (NSSI) -- deliberately harming one's body through such acts as cutting, burning or biting -- is a primary risk factor for future suicide in teens and young adults, finds a new longitudinal study of college students led by a Cornell mental health researcher.
The paper, published online Dec. 4 in the Journal of Adolescent Health, describes how NSSI, thought to be a coping mechanism for some individuals in distress, may also open the door to more dangerous actions by lowering one's inhibitions to suicidal thoughts and behaviors.
"While we can't conclude that self-injury leads to later suicide attempts, it is a red flag that someone is distressed and is at greater risk," said lead author Janis Whitlock, Ph.D. '03, a research scientist in the Bronfenbrenner Center for Translational Research (BCTR). "This is important because self-injury is a relatively new behavior that does not show up much in the literature as a risk factor for suicide. It also suggests that if someone with self-injury history becomes suicidal, having engaged in NSSI may make it much easier to carry out the physical actions needed to lethally damage the body."
In a longitudinal study of 1,466 students at five U.S. colleges, Whitlock, director of the Cornell Research Program on Self-Injurious Behavior in Adolescents and Young Adults, and co-investigators found NSSI to precede or coincide with suicidal thoughts and behaviors in slightly more than 60 percent of cases observed.
Participants, most in their early 20s, answered a confidential mental health survey annually for three years that assessed their history of NSSI and suicidal thoughts and behaviors, along with demographic information and common protective and risk factors. Researchers found that, independent of other risk factors, people who had self-injured were nearly three times as likely to attempt or consider suicide, while those with a history of five or more instances of self-injury were four times more likely to do so. The study has implications for NSSI treatment and suicide prevention. Previous studies have shown as many as 20 percent of college students and 25-35 percent of teens have a lifetime history of NSSI. Given its prevalence, Whitlock noted that physicians and others who work with youth should be better trained to spot such behaviors and assess for suicide risk.
Of many protective factors considered, the study identified two that appear to help lower the suicide risk in young people with a history of NSSI. Participants who had confided in their parents about their distress and those who perceived meaning in life were significantly less likely to show suicidal thoughts and behaviors.
"Meaning in life as a protective factor is not so surprising, because many who attempt suicide report that they feel a deep and often chronic lack of life meaning," Whitlock said. "However, considering that we studied a college population, it's a surprise that the parents emerged as having such a powerful influence in young adults' mental well-being, especially since we looked at respondents' relationships with all kinds of people, including therapists. Treatments for people at risk for suicide should focus on strengthening these relationships when feasible."
Cornell co-authors on the paper include John Eckenrode, BCTR director and professor of human development, and Amanda Purington, BCTR research support specialist.
The research was supported by a grant from the American Foundation for Suicide Prevention.
Ted Boscia is assistant director of communications for the College of Human Ecology.