Teens who self-harm are 3 times more likely to commit violent crimes
According to a new study from Duke University, young people who harm themselves are three times more likely to be “dual harmers,” which means they also commit violent crimes. In addition, the researchers found that dual harmers are more likely to have a history of childhood maltreatment and lower self-control than those who only self-harm.
The findings suggest that programs designed to address childhood maltreatment or self-control among self-harmers could help to prevent violent crime.
Adolescents are particularly prone to deliberately harming themselves, often by cutting or burning. The rates of self-harm have greatly increased in recent years among youths in both the United States and the United Kingdom. Each year in the U.S., around one in four teenage girls try to harm themselves, along with one in 10 teenage boys. Across the UK, self-injury among teenage girls has risen by nearly 70 percent in three years.
“We know that some individuals who self-harm also inflict harm on others,” said study lead author Leah Richmond-Rakerd. “What has not been clear is whether there are early-life characteristics or experiences that increase the risk of violent offending among individuals who self-harm. Identifying these risk factors could guide interventions that prevent and reduce interpersonal violence.”
The Duke team collaborated with experts at King’s College London to compare young people who self-harm to those who engage in “dual-harm” behavior.
The investigation was focused on 2,232 twins born in 1994 and 1995 who were part of the Environmental Risk (E-Risk) Longitudinal Twin Study, which followed the twins over 20 years. Self-harm in adolescence was assessed through interviews at age 18, while violent offenses were assessed through a computer questionnaire at age 18 and police records through age 22.
“By comparing twins who grew up in the same family, we were able to test whether self-harm and violent crime go together merely because they come from the same genetic or family risk factors,” said Terrie E. Moffitt of Duke University, who is the founder of the E-Risk Study. “They did not. This means that young people who self-harm may see violence as a way of solving problems and begin to use it against others as well as themselves.”
The results also showed that dual harmers were more likely to have experienced victimization in adolescence, experience psychotic symptoms, or to abuse drugs and alcohol.
“Our study suggests that dual-harming adolescents have experienced self-control difficulties and been victims of violence from a young age,” said Richmond-Rakerd. “A treatment-oriented rather than punishment-oriented approach is indicated to meet these individuals’ needs.”
The study is published in The American Journal of Psychiatry.