By Lisa Rapaport

Teens who visit the emergency room for self-harm injuries have a higher risk of repeat ER visits for self-harm and suicide attempts and a higher mortality risk than their peers, a Canadian study suggests.

For the study, researchers followed 5,661 adolescents who visited Ontario emergency rooms for self-harm. They also tracked 10,731 similar teens seen in the ER for other reasons.

Compared to teens whose initial ER visit was unrelated to self-harm, adolescents treated for self-harm injuries were more than four times more likely to visit the ER for self-harm over the five-year follow-up period.

Teens initially seen for self-harm injuries were also more than three times more likely to die from all causes during the study period, and almost eight times more likely to die by suicide.

“Among adolescents who presented after self-harm, and who later had recurrent admissions for self-harm, serious and complex mental conditions were common, most prominently anxiety and mood disorders, as well as substance abuse issues, and concussion or traumatic brain injury,” William Gardner of CHEO Research Institute and the University of Ottawa in Ontario and co-authors write in CMAJ.

Adolescents who presented with self-harm were almost five times more likely to have repeat emergency department visits or hospital admissions related to self-harm, with about one in three having a repeat admission, the study found.

Average health care costs for teens initially treated in the ER for self-harm injuries were also $11,000 higher than youth whose initial ER visit was for other reasons, the study found.

These results are consistent with previous studies that have found self-harm ER visits not only increase the risk of suicide, but also increase the risk of repeated ER visits and greater use of health services, the study team writes.

Overall, researchers examined data on 403,805 youth ages 13 to 17 who went to the ER in Ontario between 2011 and 2013. From this group, researchers identified a subset treated for self-harm injuries, as well as a group of similar teens seen for other reasons.

Youth treated for self-harm injuries were slightly older on average and more likely to be female.

Although teens initially treated for self-harm injuries in the ER were more likely to die by suicide, suicide was still rare, occurring in less than 1% of the teens who came to the ER after self-harm incidents.

“Over and above an elevated suicide risk, having an emergency department visit related to self-harm is a predictor for recurrent visits to the emergency department and greater use of health services,” the study team writes.

The study wasn’t designed to prove whether or how self-harm injuries might directly lead to more ER visits or a higher risk of death from suicide or other causes. Another limitation is that researchers couldn’t examine data on suicidal thoughts, which could impact ER visits for self-harm as well as suicide attempts, the study team notes.

Even so, the findings underscore the importance of monitoring teens after ER visits for self-harm injuries and getting them follow-up care to minimize their risk of repeat injuries or suicide, the study team notes.

“Our results suggest that adolescents who present at the emergency department after self-harm would benefit from assessment for mental health or substance misuse disorders,” the study team writes.

The authors also call for research into better ways to assess mental health in the emergency department and to connect emergency departments with community mental health services.

“If adolescents presenting with self-harm have mental health or substance misuse issues, they should be connected to evidence-based community services for treatment,” the authors conclude.

SOURCE: CMAJ, online November 4, 2019.