Being bullied as a child can result in long-lasting psychological scars for both boys and girls, according to a U.S. study.
Reviewing more than two decades of data, the researchers found that bullied children, regardless of their sex, face an elevated risk of developing anxiety disorders, depression and suicidal thoughts in later years.
"We were surprised at how profoundly bullying affects a person's long-term functioning," the lead researcher, William Copeland, a clinical psychologist and epidemiologist at Duke University in Durham, N.C., said in a statement.
"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."
An earlier study, carried out in Finland, came to slightly different conclusions. Bullied boys seem to suffer few long-term problems, but the girls showed evidence of lasting psychological harm. The Finnish study relied on health-system data, but did not have access to individual case histories.
The U.S. researchers said their new study, published Wednesday in the journal JAMA Psychiatry, is "most definitive to date in establishing the long-term psychological effects of bullying."
They said they used "a much richer data set" than the Finnish researchers. In particular, the analysis is based on a sample of 1,420 children from North Carolina. At the time of recruitment into the study, the kids were either 9, 11 or 13 years of age. The children and their parents, or caregivers, were interviewed each year until the youngsters turned 16, and then periodically thereafter. At each assessment, they were asked if the kids had been bullied in the preceding months, or had bullied others.
A total of 421 participants reported being bullied at least once. And 198 youngsters admitted bullying others: 112 were bullies only, while 86 were both bullies and victims.
Of the original 1,420 children, about 1,270 were followed into adulthood.
"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," according to the study.
What's more, the study found that those who had been bullies were at increased risk of antisocial personality disorders.