(Newsroom America) -- Teenagers injured through drinking, drug abuse or self-harming have a five-fold increased risk of dying from suicide in the next decade.
Children and young people admitted to hospital in England with injuries related to self-harming, drugs or alcohol faced an increased risk of killing themselves over the following 10 years, according to new research.
While previous studies have shown that children and adolescents who self-harm are at a higher risk of suicide, the paper by academics from UCL and the University of Leeds, argues that the risks apply to a larger group of adolescents.
The researchers say children injured through drink or drugs faced a similar increased risk of suicide as children who had been self-harming - and the National Health Service needed to revise its guidelines to target help and support at these young people.
The study examined anonymous hospital data relating to more than one million young people aged 10 to 19 who were admitted to an emergency department in England between 1997 and 2012 having suffered an injury.
The injuries were categorised as having been caused either accidentally - or through 'adversity', where the injuries were self-inflicted, from drug or alcohol abuse, or violence. The research team then looked at what had happened to the young people in the decade following the hospital admission.
They found that the death rate among the group which had suffered the adversity-related injuries was twice as high as the youngsters who had suffered the accidental injuries.
Among the adversity group, the death rate for girls was 7.3 per 1,000 - and 15.6 per 1,000 for boys. Two-thirds of the deaths were attributable to suicide, drug or alcohol misuse or to homicide, according to the research which is published in the Lancet.
One of the key findings of the study was that the risk of suicide was similar between young people who had self-harmed and those who had misused drugs or alcohol - an observation not been reported in medical journals until now.
The suicide rate of these young people was about five-times of that seen in the accidental injury group. The researchers also found that young people who had self-inflicted injuries were just as likely to die from drug and alcohol misuse as from suicide.
The increased rates of deaths from suicide or drug and alcohol misuse in the adversity group resulted in an additional 1,075 deaths - 683 boys and 392 girls.
This was an observational study, so it can increase our understanding of possible links between self-inflicted injury and suicide, but it doesn't show that one necessarily causes the other because other factors could be involved.
Young Minds is a UK charity seeking to promote better mental health among adolescents. Its chief executive, Sarah Brennan, said: "This ground-breaking research demonstrates some of the interconnections between self-harm, substance misuse and violent injury - and the tragic consequences that these experiences may have. "It is essential that we don't think of young people simply in terms of a list of "issues", and that we understand how distress can be expressed in different ways at different times."
The study showed young people are arriving at hospital with injuries which are not being identified as 'red flags' of an increased risk of a premature death.
David Cottrell, Professor of Child and Adolescent Psychiatry at the University of Leeds and one of the investigators, said: "Clinicians have not fully appreciated the risks facing children and young people who arrive in hospital emergency departments having suffered an adversity-related injury.
"It is well established that children who self-harm are at an increased risk of suicide.
"But the research points to that fact that the risk extends to a much broader group. Children and young people who suffered injuries through drink or drugs or violence also faced an increased risk of suicide or premature death through alcohol and drug behaviours."
"These young people are coming into contact with the health services and that means there's an opportunity for them to get help and support. Based on this evidence, official guidance given to staff in emergency departments needs to be reviewed so these young people are also seen as being at risk."
It is standard practice for a mental health professional to assess a young person who has a self-inflicted injury, but that does not extend to those injuries related to misusing alcohol or drugs or to violence.
The researchers say mental health support should also be targeted at all children suffering adversity-related injuries. Dr Annie Herbert, from UCL Institute of Epidemiology and Healthcare, said: "A huge amount of deaths after adversity-related injury in our study were from suicide or drug or alcohol abuse, which to an extent should be preventable.
"More research is needed to find the best way for clinicians to support these children and young people, to reduce risks of future harm after they leave hospital."
Professor Ruth Gilbert, from UCL Great Ormond Street Institute of Child Health, said: "Our findings show the enormous value of using routinely collected patient data to spot opportunities for the NHS to intervene to reduce the risk of harm for vulnerable patients, many of whom come back to hospital time and again."