It's obvious that youngsters who harm themselves need psychiatric care, but drugs, alcohol, and violent injuries should set off similar mental-health alarm bells, researchers say.
In a study from the UK, the risk of suicide 10 years after adolescents were hospitalized for drug problems, alcohol abuse or violent injury was similar to the risk among those hospitalized for self-harm.
"All of these kids should be having a psychological assessments," said lead author Annie Herbert, of University College London.
Herbert and colleagues write in The Lancet that substance abuse, violence and self-inflicted injuries are all forms of self-harm that likely share underlying psychological issues related to adversity, poor mental health and poor social circumstances like poverty.
For the new study, Herbert's team tracked adolescents who were hospitalized between 1997 and 2012 for accidental injuries or for "adversity-related injuries" (i.e., self-inflicted, drug-related or alcohol-related, or violent injuries).
The children were 10 to 19 years old at the start of the study. Overall, the researchers had data on nearly 650,000 adolescents with accidental injuries and 333,000 with adversity-related injuries. Altogether, a small number of them - fewer than one percent - died within 10 years of being hospitalized.
Overall, the risk of death in those next 10 years was twice as high for adolescents hospitalized for adversity-related injury (7.3 deaths per 1000 girls and 15.6 per 1000 boys) than after accidental injuries (3.8 per 1000 girls and 6.0 per 1000 boys).
Among those who died, the likelihood that death was caused by suicide, drug or alcohol use, or homicide was much higher if they'd been hospitalized for an adversity-related injury.
The risk of suicide during the study period was similar for adolescents hospitalized for self-harm (2.9 per 1000 girls and 9.8 per 1000 boys) or for drug or alcohol-related injuries (2.5 per 1000 girls and 7.2 per 1000 boys).
As a group, for the youngsters hospitalized for self-harm or drug or alcohol-related injuries, the risk of suicide was five to six times higher than it was for children hospitalized after accidents.
Herbert said parents should share information about their adolescents' activities with their doctors.
"If the parent has additional information about self-harm and violence, that may encourage more follow up," she told Reuters Health.
These youngsters need long-term, detailed care, suggest George Patton and Rohan Borschmann, of Royal Children's Hospital in Parkville, Australia.
They write in an editorial accompanying the new study that temporary help for these adolescents is inadequate since the risks appear to be heightened for at least a decade.
"Health-care professionals should no longer see an adolescent presenting in distress as a nuisance, wasting valuable clinical time, but as a vulnerable person deserving the second chance that responsive and sustained health care can provide," they write.