(Reuters Health) - Teens and young adults who harm themselves without suicidal intent often kill themselves soon afterward, and the increased risk of death is greatest when guns are involved, a U.S. study suggests.
Researchers examined insurance-claim data on more than 32,000 patients ranging from 12 to 24 years old who were followed for one year after a nonfatal self-harm episode. Unlike suicide attempts, which require suicidal intent, episodes of self-harm can also include poisoning, cutting, firearms or other violent methods used to cause nonfatal injuries.
Poisoning was by far the most common method of self-harm, accounting for 65 percent of cases, followed by cutting at 18 percent, the study found. Guns were used in slightly less than 1 percent of cases.
When youth did use guns to harm themselves, however, they were more than 35 times more likely to kill themselves over the next year compared with teens and young adults whose acts of self-harm involved other methods, the study found.
“How young people injured themselves was a strong predictor of future suicide risk,” said lead study author Dr. Mark Olfson, a psychiatry researcher at Columbia University in New York City.
“More violent methods such as firearms or hanging carried much greater risk than less violent methods such as cutting or poisoning,” Olfson said by email.
Nonfatal self-harm is common among young people, and suicide is the second leading cause of death among Americans aged 15 to 24, researchers note in Pediatrics. Nearly one-third of young people who die of suicide have nonfatal self-harm events in their final three months of life.
In the current study, many of the teens and young adults had been recently diagnosed with substance abuse problems or mental health issues like depression or anxiety. Almost half of them had recently received outpatient mental health care.
Youth with personality disorders were 55 percent more likely to have repeat self-harm episodes, and the risk increased by 65 percent if they received inpatient care.
But roughly one in four youth in the study had no diagnosis of mental health or substance abuse problems before they harmed themselves.
The analysis wasn’t a controlled experiment designed to prove whether or how the method of self-harm might impact the potential for young people to kill themselves. Another limitation is that the insurance claims records didn’t identify patients with suicidal intent.
A separate study in Pediatrics highlighted another, independent risk factor for suicide in teens: homelessness.
Researchers examined survey data on more than 62,000 teens enrolled in school in Minnesota, including about 4,600 youth who were homeless and living with an adult family member.
Homeless youth were more likely to be boys, non-white, poor and living outside of urban areas.
Overall, about 29 percent of these homeless teens reported self-injury, 21 percent reported suicidal thoughts and 9 percent reported suicide attempts.
Compared to non-homeless youth, homeless teens were roughly twice as likely to report self-injury and suicidal thoughts, and more than three times as likely to attempt suicide.
This study also wasn’t a controlled experiment designed to prove whether or how homelessness might influence self-harm or suicide among teens.
Still, it offers fresh evidence of the severe emotional distress experienced by homeless youth, said lead author Dr. Andrew Barnes of the University of Minnesota Medical School in Minneapolis.
“Youth who have been homeless have often had a lot of negative, highly stressful things happen in their lives as they’ve grown up,” Barnes said by email.
“On top of that, they are more likely to be members of historically oppressed racial or ethnic groups, and to have suffered from discrimination, harassment, and social marginalization,” Barnes added. “All of that takes a toll on healthy development - not only their mental health, but their physical health and academic achievement.”
Stability and support might make self-harm and suicide less likely for these vulnerable teens, however.
“Building loving and positive relationships with parents, teachers and their child’s school does reduce their teens’ risk of suicide,” Barnes said. “So does promoting their teens’ sense of positive self-identify, connection to their community and sense of purpose.”