Children abused by adults are known to be at increased risk of developing the serious and persistent mental illness known as borderline personality-disorder (BPD). New research suggests that bullying and victimization by other children during the elementary school years should be acknowledged as another important risk factor.
Psychologists in Britain, Germany and the United States base their conclusions on an analysis of data from the Avon Longitudinal Study of Parents and Children (ALSPAC) which has followed the development of more than 6,000 mothers and children in south west England since pregnancy in the early 1990s.
After comparing the results of diagnostic interviews with the children when aged 11 with reports of bullying gathered when they were aged 8 and 10, they conclude that intentional harm inflicted by peers is a significant precursor of BPD symptoms – although it could be a “marker” for the increased level of risk, rather than a direct cause.
Dieter Wolke of Warwick University and his colleagues note that BPD is a chronic psychiatric condition estimated to affect between 0.7 per cent and 5.9 per cent of the adult population. Its characteristics include poor mood and impulse control, unstable and intense personal relationships, and severe difficulty trusting the actions or motives of others.
Threats, rumours and lies
Existing studies have linked BPD to childhood experiences of physical and sexual abuse, neglect and exposure to domestic violence. In addition, bullying or “peer victimization” in childhood has been associated with the emergence of psychotic symptoms and suicidal thoughts as well as adverse neurobiological changes in the brain.
This makes it all the more surprising that potential links with BPD have not been investigated before and that this study is, so far as the authors know, the first to use longitudinal data to explore the connection.
Wolke and his colleagues not only analyzed data collected from children in the ALSPAC survey, but also interviews with parents and teachers about victimization when the children were as young as 4. Information gathered on the children’s home life, well-being and IQ was taken into account to rule out other possible explanations for the link between bullying and BPD symptoms, including sexual abuse and harsh, maladaptive parenting.
The association between BPD and different types of bullying was investigated by making a distinction between “overt victimization” where victims are physically hurt or threatened and “relational victimization” involving exclusion from play by peers or the circulation of rumours and lies. The researchers also examined “dosage”, considering whether bullying was reportedly chronic or severe.
Pinpointing lessons for prevention
The results showed that any experience of peer bullying in primary (elementary) school was significantly linked to the emergence of BPD symptoms in children under 12. This association was strong and remained so even after controlling the data for other, potentially “confounding”, explanations.
The study also found that the risk of developing symptoms increased among children who had experienced chronic bullying or a combination of “overt” and “relational” victimization. For children who said they were victims of both types of bullying the odds of BPD symptoms were increased seven times compared with children who were not bullied. For children who reported being bullied at age 8 and again at age 10, the odds 5.5 times greater than for those who had never been victimized.
Turning to potential explanations, the researchers highlight the capacity for bullying to work its way “under the skin” of its victims, both psychologically and functionally. However, they also recognize that children who get bullied tend to have fewer friends anyway and are often more withdrawn, physically weaker, and more easily upset than their peers. Their victimization could, consequently, be a “marker” within a developmental risk factor model for BPD, rather than an actual cause.
The development of BPD, as with other mental health disorders, is a complex matter. It is not, however, difficult to see why this latest study – soundly based in data from a major longitudinal study – holds important implications for prevention.
At a universal “whole school” level, it underlines the value of applying structured, evidence-based strategies that prevent victimization and facilitate swift and effective action when bullying occurs. But it also points to the need for clinicians working with children who already exhibit significant mental health problems to be alert to the links between BPD and bullying by peers.
As the authors of the new study suggest, professionals in child and adolescent mental health should be routinely asking children and young people about victimization – and be properly trained to deal with the answers.