Nonsuicidal Self-Injury: A Neglected Public Health Problem Among Adolescents

In this issue of AJPH, Monto et al. (p. 1042) take an important step in providing prevalence estimates and health risk behavior correlates of nonsuicidal self-injury (NSSI) among a large nonclinical sample of high school students in 11 states using 2015 Youth Risk Behavior Surveillance System (YRBSS) data. They found that 17.6% of adolescents had engaged in at least one form of NSSI within the past year, including just over one in 10 male adolescents and nearly one in four female adolescents. This work adds to the current body of epidemiological research on NSSI and demonstrates a substantial population-level burden of NSSI among youths. It also builds on research from the 2007 Minnesota Student Survey, a population-based survey of Minnesota high school students that found an NSSI prevalence of 7.3% among youths who had never experienced suicidality.¹ The 2016 Minnesota Student Survey employed an NSSI question similar to that of the YRBSS and showed rates (15%–16%) comparable to those observed by Monto et al.

DISENTANGLING NSSI AND SUICIDALITY

Monto et al. found strong associations between NSSI and past-year suicide attempts, consistent with previous research demonstrating that adolescents who engage in NSSI are at an increased risk of subsequently attempting suicide. In fact, several studies suggest that specifically among adolescents who are depressed, a history of NSSI may be a stronger risk factor for attempting suicide than is a past suicide attempt.²

NSSI poses a particular challenge for youth-serving clinicians and mental health systems. Youths are often evaluated in emergency departments for NSSI, and many are admitted unnecessarily to psychiatric inpatient programs. Because the behavior is, by definition, not suicidal in intent, many youths may be best served with community-based mental health treatment. However, in research and clinical assessment, it is often challenging to determine which youths engaging in NSSI require inpatient hospitalization. Future work is urgently needed to differentiate youths at the highest risk for suicide, appropriately triage services, and guide best practices.

FRONTIERS IN NSSI RESEARCH

Monto et al. fill an important gap in NSSI research by exploring health risk behaviors rarely examined among adolescents who self-injure (e.g., using drugs, fighting, cyberbullying, forced sexual intercourse). Importantly, although the prevalence of NSSI varied by sex, the pattern of associated risk factors was generally consistent among both male and female students. The association of NSSI with health risk behaviors highlights the importance of assessing the broader context in which NSSI occurs. Although these associations bring to light cooccurrence patterns, they cannot be used to assess causation or to evaluate the possibility of reverse causation.

Another important step in advancing NSSI research is to move beyond examining NSSI as either present or absent and study frequency and patterns of NSSI behavior. Many youths search for new strategies to cope with emotional distress, and some try NSSI once or twice to determine whether it is helpful to them and stop when it is not. As in the study by Monto et al., these adolescents are often grouped with those who have integrated NSSI into their regular coping repertoire. Although small studies often lack the power to examine NSSI frequency, YRBSS offers the opportunity to conduct this more detailed analysis. Monto et al. noted that 5.5% of the sample had engaged in NSSI six or more times in the previous 12 months, providing a valuable data source for more detailed study of risk profiles.

USING THEORY TO INFORM RESEARCH AND PRACTICE

Disentangling NSSI and suicidality speaks to a broader discussion about how best to identify youths engaged in risk behaviors who will actually attempt suicide. The interpersonal psychological theory of suicide³ posits that individuals attempt suicide when they have both a desire to die (i.e., suicidal ideation) and the capability to act on that desire. According to the interpersonal psychological theory of suicide, individuals who ideate about suicide attempt suicide only if they have acquired the capability to tolerate the anticipated physical pain and have a decreased fear of death. Individuals who engage in NSSI may become habituated to various forms of pain (e.g., tearing, burning, bruising) so that death by suicide is not as frightening over time.

However, it is not simply whether individuals engage in NSSI that increases the risk for a suicide attempt but how many times they self-injure, how long they have been self-injuring, how many different methods of NSSI they have used, and why they engage in NSSI (e.g., to release tension, to avoid suicide, to self-punish). It is essential that we balance studies of population-level prevalence and correlates of NSSI with theoretically grounded examinations of how these risk behaviors actually unfold across the adolescent life course. In doing so, we can bring together multidisciplinary perspectives from youths, clinicians, researchers, and public health officials to move the field forward.

A PUBLIC HEALTH FRAMEWORK FOR INTERVENTIONS

The health impact pyramid outlined by Frieden⁴ provides a useful framework from which to conceptualize the public health impact of NSSI and identify intervention opportunities beyond traditional individual-based approaches. This model posits that the greatest population effect with the least amount of individual effort can be achieved by targeting socioeconomic and sociostructural factors. In the case of NSSI, this should include sustained efforts to address mental health parity and improve access to mental health care for all youths.

Changing social and environmental contexts to promote healthy behavior has been successfully used to address suicide. Suicide research has demonstrated the effectiveness of structural interventions, such as fencing around bridges and the tops of high buildings.⁵ Additionally, changes in media reporting practices have successfully reduced the suicide copycat phenomenon. More responsible reporting of NSSI in the media, including discussing negative consequences and focusing on help-seeking behavior and available resources, may provide novel avenues for harm reduction.

School-based prevention programs, such as the Signs of Self-Injury Program,⁶ may offer opportunities for long-lasting protective interventions. Such programs can foster empathy for those engaging in NSSI and improve help-seeking attitudes and intentions among youths. They may prove a particularly efficient approach considering the NSSI burden documented by Monto et al.

Family- and individual-level clinical interventions may also play an important role in addressing NSSI. There are no empirically supported treatments specifically for adolescent NSSI, but most treatments that help with NSSI do so by addressing the context in which it occurs (e.g., depression).⁷ Research has shown that supportive and positive family relationships are one of the greatest protective factors against many health risk behaviors, including NSSI.¹

Few medical providers feel prepared to address NSSI at the individual level through counseling or education, and few resources exist to help them. However, one model has been developed as a tool to assist health professionals with screening adolescents for NSSI and providing brief, targeted advice and counsel.⁷ Because of the high prevalence of NSSI among both male and female adolescents, youth-serving professionals should incorporate routine screening for NSSI and link to appropriate mental health services as part of best practices in assessing psychosocial risk and protective factors that affect health.

A comprehensive strategy to address adolescent NSSI must combine research, the refinement of clinical best practices, and the development of multitiered prevention and intervention programs, including public health programs to address NSSI among youths in the general community. This integrated approach can help us identify effective individual and contextual strategies to reduce the burden of NSSI and safeguard youths.