Children who have been bullied by peers have similar or worse long-term mental health outcomes than children maltreated by adults, according to a study to be presented Tuesday, April 28 at the Pediatric Academic Societies (PAS) annual meeting in San Diego, and to be published in The Lancet Psychiatry at the same time.

The consequences of by adults are well-documented. Being bullied also can lead to problems later in life. However, it is not known whether long-term among victims of are related to having been maltreated by adults as well.

To determine the effects of bullying on mental health, researchers compared young adults in the United States and the United Kingdom who had been maltreated, bullied or both during childhood. Subjects from the U.K. were part of the Avon Longitudinal Study of Parents and Children (ALSPAC), and U.S. subjects were part of the Great Smoky Mountain Study (GSMS).

Researchers analyzed data from 4,026 ALSPAC participants on reports of maltreatment between the ages of 8 weeks and 8.6 years; bullying at ages 8, 10 and 13; and mental health outcomes (anxiety, depression, self-harm/suicidality, overall mental health problems) at age 18. Data were available for 1,273 participants in the GSMS on maltreatment and bullying between the ages of 9 and 16, and mental through ages 19-25.

Results showed that in general, and adolescents were more likely to experience abuse from peers than from parents or other adults.

In the ALSPAC group, 8.5 percent of children were exposed to maltreatment only, 29.7 percent to bullying only and 7 percent to both maltreatment and bullying. In the GSMS group, 15 percent were maltreated only, 16.3 percent were bullied only and 9.8 percent were maltreated and bullied.

In both groups, maltreated children were more likely to be bullied than those not maltreated.

After adjusting for confounders such as family adversity, prenatal maternal mental health problems and socioeconomic status, maltreatment alone did not increase the risk of any mental health problem among youths in the ALSPAC group and increased the risk of depression in the GSMS group.

Those who were bullied were more likely to suffer from any than those maltreated only. Specifically, children in the GSMS group who were bullied were more likely to suffer from anxiety, while those in the ALSPAC group were more likely to experience depression and self-harm/suicidality than those who were maltreated.

Being both maltreated and bullied also increased the risk of overall mental , anxiety and depression in both groups and self-harm/suicidality in the ALSPAC group.

"Being bullied is not a harmless rite of passage or an inevitable part of growing up; it has serious long-term consequences," said study author Dieter Wolke, PhD, professor of developmental psychology and individual differences, The University of Warwick, U.K., and professor of psychology, Warwick Medical School. "It is important for schools, health services and other agencies to work together to reduce bullying and the adverse effects related to it."

Governmental efforts have focused almost solely on public policy to address family maltreatment, and much less attention and resources have been paid to bullying, Dr. Wolke added. "Hence, this imbalance in governmental efforts requires attention."

More information: Dr. Wolke will present "Adult Mental Health Consequences of Peer Bullying and Maltreatment in Childhood: Two Cohorts in Two Countries" from 10:30-10:45 a.m. Tuesday, April 28. To view the study abstract, go to http://www.abstracts2view.com/pas/view.php?nu=PAS15L1_4540.4

The Lancet Psychiatry, www.thelancet.com/journals/lan … 2215-0366(15)00165-0