Bullied children grow into adults who are at increased risk of developing anxiety disorders, depression and suicidal thoughts, according to a study led by researchers at Duke Medicine.
The findings, based on more than 20 years of data from a large group of participants initially enrolled as adolescents, are the most definitive to date in establishing the long-term psychological effects of bullying.
Published online Feb. 20, 2013, in JAMA Psychiatry, the study belies a common perception that bullying, while hurtful, inflicts a fleeting injury that victims outgrow.
"We were surprised at how profoundly bullying affects a person's long-term functioning," said William E. Copeland, PhD, assistant clinical professor in the Department of Psychiatry and Behavioral Sciences at Duke University and lead author of the study. "This psychological damage doesn't just go away because a person grew up and is no longer bullied. This is something that stays with them. If we can address this now, we can prevent a whole host of problems down the road."
A previous longitudinal study of bullied children, conducted in Finland, found mixed results, concluding that boys had few lasting problems, while girls suffered more long-term psychological harm. That study, however, relied on registry data in the health system that didn't fully capture psychiatric records.
Copeland and colleagues had a much richer data set. Using the Great Smoky Mountain Study, the research team tapped a population-based sample of 1,420 children ages 9, 11 and 13 from 11 counties in western North Carolina. Initially enrolled in 1993, the children and their parents or caregivers were interviewed annually until the youngsters turned 16, and then periodically thereafter.
At each assessment until age 16, the child and caregiver were asked, among other things, whether the child had been bullied or teased or had bullied others in the three months immediately prior to the interview.
A total of 421 child or adolescent participants – 26 percent of the children - reported being bullied at least once; 887 said they suffered no such abuse. Boys and girls reported incidents at about the same rate. Nearly 200 youngsters, or 9.5 percent, acknowledged bullying others; 112 were bullies only, while 86 were both bullies and victims.
Of the original 1,420 children, more than 1,270 were followed up into adulthood. The subsequent interviews included questions about the participants' psychological health.
As adults, those who said they had been bullied, plus those who were both victims and aggressors, were at higher risk for psychiatric disorders compared with those with no history of being bullied. The young people who were only victims had higher levels of depressive disorders, anxiety disorders, generalized anxiety, panic disorder and agoraphobia.
Those who were both bullies and victims had higher levels of all anxiety and depressive disorders, plus the highest levels of suicidal thoughts, depressive disorders, generalized anxiety and panic disorder. Bullies were also at increased risk for antisocial personality disorder.
The researchers were able to sort out confounding factors that might have contributed to psychiatric disorders, including poverty, abuse and an unstable or dysfunctional home life.
"Bullying is potentially a problem for bullies as well as for victims," said senior author E. Jane Costello, PhD, associate director of research at Duke's Center for Child and Family Policy. "Bullying, which we tend to think of as a normal and not terribly important part of childhood, turns out to have the potential for very serious consequences for children, adolescents and adults."
Costello and Copeland said they would continue their analysis, with future studies exploring the role sexual orientation plays in bullying and victimization.
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