Self-injury is more common than most people realize, although the incidence has begun to stabilize over the last five years, according to psychologist Janis Whitlock, PhD, who heads the Cornell Research Program on Self-Injury and Recovery.
The condition — clinically known as non-suicidal self-injury or NSSI — is characterized by deliberate self-inflicted harm that isn't intended to be suicidal. People who self-harm may carve or cut their skin, burn themselves, bang or punch objects or themselves, embed objects under their skin, or engage in myriad other behaviors that are intended to cause themselves pain but not end their lives. (For the most part, tattooing and piercing are not considered NSSI because they are culturally sanctioned forms of expression, says Whitlock.)
The most frequent sites of self-injury are the hands, wrists, stomach and thighs, though self-injurers may hurt themselves anywhere on the body. Results can be serious: About a third of students reporting NSSI in two college studies said they had hurt themselves so badly that they should have been seen by a medical professional, but only 5 percent sought treatment, according to a random sample of students in eight colleges and universities reported in a 2011 article by Whitlock and colleagues in the Journal of American College Health.
Overall, about 15 percent of college students in that sample had engaged in NSSI at least once, that team also found.
As for adolescents, about 17 percent had engaged in NSSI at least once, according to an international meta-analysis of 52 studies, conducted by psychologist Jennifer Muehlenkamp, PhD, of the University of Wisconsin–Eau Claire and colleagues (Child and Adolescent Psychiatry and Mental Health).
Reported self-injury is much less common in adults — about a 5 percent lifetime rate — and in most children. Overall, about 1.3 percent of youngsters ages 5 to 10 self-injure, though rates climb significantly if the child has a diagnosed anxiety disorder or chronic mental distress, studies show.
Young white females tend to represent the public's perception of NSSI, but at least 35 percent and as many as half of self-injurers may be male, studies also show. The number is uncertain in part because males present differently from females and may, therefore, be underreported, Whitlock says. Females are more likely to engage in self-cutting, she says, while males are more prone to deliberately bruising themselves, hurting themselves while taking a substance, or having others hurt them.
Demographic research shows that people self-injure regardless of race or socioeconomic status, but that sexual minority status may put young people more at risk. More gay or bisexual males report self-injury than heterosexual males, and bisexual females are especially vulnerable: About 47 percent of bisexual females (as measured by their ratings on the Kinsey scale on sexual orientation) self-injure, finds the 2011 eight-college review.
In a related vein, young people who are bullied or otherwise rejected by peers are more likely to self-injure than others. A 2015 study in the Journal of Child and Family Studies by Laurence Claes, PhD, and colleagues found that among 78 teens, those who were bullied or reported feeling victimized by bullying were more likely to injure themselves, and that depression intensified this association. Similarly, a 2015 study in the Journal of Consulting and Clinical Psychology by Matteo Giletta, PhD, and colleagues found that of 565 Chinese adolescents who reported depressive symptoms at baseline, those who also reported greater peer victimization were more likely at the end of three years to self-injure than those who reported less peer harassment.
Those who self-injure also are more prone to depression, hopelessness and dissociation, research also finds. Thus, researchers are studying the role of emotion dysregulation — difficulty discriminating between emotional states or knowing how to cope with or extricate oneself from negative emotional states — and finding a strong link with self-injury.
Research also finds that NSSI is a strong predictor of later suicide attempts. In a 2013 study reported in the Journal of Adolescent Health, Whitlock, Muehlenkamp and colleagues followed 1,466 students at five American colleges over three years. Students who self-injured at the beginning and did not report suicidal thoughts, plans or actions at the time, but who went on to engage in 20 or more self-injuring behaviors, were 3.4 times more likely to have attempted suicide by the study's end.
Other risk factors are under the microscope as well. These include self-injurers' ability to endure pain, low feelings of self-worth (see article, page 59), tendency to objectify the body, and risk factors that overlap with those of other conditions like eating disorders.
Muehlenkamp is examining body objectification as an important potential factor in the development and maintenance of NSSI. The notion holds that when people see their own body as an object — the result of internalized cultural and familial pressures — it's easier to distance themselves psychologically from their bodies and hence to harm themselves.
A 2013 study by Muehlenkamp and colleagues in Suicide and Life-Threatening Behavior supports this hypothesis. Males and females with poor body regard who also scored high on emotion dysregulation were more likely to self-injure than people with poor emotion regulation but normal body regard.
The findings suggest a potentially significant commonality between NSSI and eating disorders, which are present in as many as 55 percent of those who self-injure, Muehlenkamp adds.
"Body objectification, body devaluation and a lack of internal bodily awareness are also prevalent in that population," she says.
Muehlenkamp also hopes to study the mindfulness component of dialectical behavior therapy, which she feels might help NSSI sufferers address their body image problems gently and gradually.
"To become more mindful means you have to become more in tune with your body, more connected to it, more integrated with it," she says. Such body awareness may potentially undermine one's tendency to objectify the body, hence reducing the risk for self-injury, she posits.
— Tori DeAngelis