CLEVELAND - Children identified as bullies were three times more likely to be diagnosed with mental health problems, according to new research.
Dr. Elaine Schulte wasn't involved in the study but is a pediatrician at Cleveland Clinic Children's Hospital.
"A lot of these kids have mental health issues like depression, anxiety, oppositional defiant disorder, attention deficit hyperactivity disorder, or ADHD, so these are kids who are already struggling with their own stuff and then they're acting out and bullying other children," Schulte said.
Researchers studied information provided by parents and guardians of 64,000 children from the 2007 National Survey of Children's Health.
Results show that 15 percent of children were considered bullies by their parent or guardian. Kids diagnosed with a mental health disorder were three times more likely to bully other children.
Children diagnosed specifically with depression were three times more likely to bully. Meranwhile, those diagnosed with oppositional defiant disorder -- where hostile and angry behavior is often directed toward authority figures -- were six times more likely to be a bully.
The findings aren't a surprise to pediatricians, Schulte said.
"These are kids who are hurting. Bullies don't intentionally act out on other children. They can't control their behavior and parents need to deal with it, schools need to deal with it and it's a real problem nationwide," she added.
Results for this study recently were presented at the American Academy of Pediatrics National Conference.
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