MedicalResearch.com Interview with:
Tracy Vaillancourt, Ph.D.
Full Professor and Canada Research Chair
Children’s Mental Health and Violence Prevention
Counselling Psychology, Faculty of Education
School of Psychology, Faculty of Social Sciences
University of Ottawa
MedicalResearch.com: What is the background for this study?
Response: Although there have been a few studies that have looked at the relation between being bullied and disordered eating, most studies have looked at it from the perspective of does being bullied lead to disordered eating and does depressive symptoms mediate (i.e., explain) the link. We wanted to look more closely at how bullying, disordered eating, and depression were related over time among teenagers by examining all possible pathways.
Another novel aspect of our study was the focus on disordered eating behaviour only (e.g., vomiting, using diet pills, binge eating). Most previous work has examined behaviour and thoughts together, but because disordered eating thoughts are so common (termed normative discontent; e.g., fear of fat, dissatisfaction with body shape or size), particularly among girls and women, we wanted to focus on behaviour, which is more problematic in terms of physical and psychiatric health.
MedicalResearch.com Interview with:
Dr. Lucy Bowes Ph.D
Leverhulme Early Career Research Fellow
Fellow of Magdalen College
Department of Experimental Psychology
University of Oxford Oxford
Medical Research: What is the background for this study? What are the main findings?
Response: Major depression is a severe mental illness, and a leading contributor to the global burden of disease. Rates of depression begin to rise in the teenage years, though the reasons for this remain unclear. Peers become particularly important during this time, and victimisation by peers or “bullying” has been proposed as one potentially modifiable risk factor for depression. There are robust findings that peer victimisation in childhood is associated with short-term internalizing symptoms, however it remains unclear whether victimization in the teenage years is associated with major depression. Only a relatively small number of longitudinal studies have prospectively investigated victimisation in relation to depression meeting diagnostic criteria in late adolescence or adulthood. Limitations of these studies include poor measures of bullying, lack of adjustment for key confounders such as baseline emotional and behavioral difficulties and child maltreatment.
Our prospective cohort observational study, published in The BMJ, used detailed self-report data on peer victimisation at 13 years from 6,719 participants of the ALSPAC or ‘Children of the 90s’ study. The outcome was depression at 18 years, measured using a self-administered computerised version of the Clinical Interview Schedule Revised, CIS-R (data available for 3,898 participants). We adjusted for a range of confounders including baseline emotional and behavioral problems, family background and other risk factors. Of the 683 children who reported frequent victimisation at 13 years, 101 (14.8%) were depressed at 18 years. Of the 1,446 children reporting some victimisation, 103 (7.1%) were depressed, and of the 1,769 children reporting no victimisation at 13 years, 98 (5.5%) were depressed. Children who were frequently victimized had over a two-fold increase in odds of depression compared with children who were not victimized by peers. This association was slightly reduced when adjusting for key confounders. The population attributable fraction suggested that 29% of depression at 18 could be explained by peer victimisation if this were a causal relationship.
Melissa K. Holt, PhD
School of Education, Boston University
MedicalResearch.com: What are the main findings?
Dr. Holt: Results from this study indicated that among the sample of adolescents surveyed, bullies and bully-victims (i.e., youth who are both perpetrators and targets of bullying) engaged in more sexual risk taking behaviors than their peers. Specifically, they were more likely to report casual sex and sex under the influence of alcohol or drugs. For instance, 33.8% of bullies and 23% of bully-victims reported sex under the influence of alcohol or drugs in contrast to 14% of youth not involved in bullying. Notably, findings suggested that bullying involvement might be a more salient predictor of sexual risk taking for heterosexual than GLBTQ adolescents.