WEDNESDAY, Jan. 7, 2015 (HealthDay News) -- A new analysis of research from around the world suggests that kids involved in bullying are at higher risk of suicidal thoughts and actions.
Kids who bullied others and were victims themselves were the most troubled of all, the report found.
"Our study highlights the significant impact bullying involvement can have on mental health for some youth," said study lead author Melissa Holt, an assistant professor of counseling psychology at Boston University.
Researchers already know that there's a connection between bullying -- being a victim, a bully, or both at different times -- and suicidal thoughts, said Robert Faris, an associate professor of sociology at the University of California, Davis, who studies bullying. It's also clear that the link is stronger for the victims of bullying, he said.
However, "we also know that bullying alone does not directly cause suicide," he said, and it's not clear "how we get from being bullied to suicide."
Holt also stressed that although the study found an association, it couldn't prove cause and effect.
"Involvement in bullying, as a victim or perpetrator, is not by random assignment, so it's possible that the factors that lead kids to bully or be victimized also lead them to consider suicide," Faris reasoned.
In the new report, researchers tried to get a global handle on the potential risks of bullying. To do so, they analyzed 47 studies of bullying from around the world, including 18 from the United States.
"Victims, bullies, and those youth who both bully others and are bullied all report significantly more suicidal thoughts and behaviors than youth who are uninvolved in bullying," study lead author Holt said.
The analysis suggests that those who are bullies and bullied themselves are at greatest risk of having suicidal thoughts and behaviors.
According to the study, prior research has suggested that so-called "bully victims" -- kids who fall into both categories of bully and victim -- are often more likely to suffer from depression and anxiety compared to bullies and victims of bullying.
In the new analysis, these "bully victims" had four times the odds of suicidal thoughts and behaviors, compared to those who weren't exposed to bullying.
Victims (only) of bullying had odds for suicidal thoughts and behaviors that were more than twice that of people not bullied, and rates were similar for people who were bully perpetrators only.
Why might bullies be suicidal in the first place?
"Some bullies are emotionally and psychologically maladjusted, and these are risks for suicidal thoughts," Faris said. "But on top of that, bullying has the potential to cause a lot of distress for bullies, either because their bullying has backfired, or because it is distressing to be feared, avoided or hated."
As for the report itself, Faris said it's "definitely valid." And, he added, it supports "the link between involvement in bullying and suicidal thoughts and behaviors. Hopefully, scholars can put that basic question to bed now."
The analysis appears in the February issue of the journal Pediatrics.
For more on bullying, head to the U.S. Department of Health and Human Services.