Depression and anxiety have a larger impact on bullied girls than on boys to experience self-harm and suicidality: A mediation analysis

Background: The mechanism underlying the correlation between bullying victimization, self-harm and suicidality by gender are not well understood. This study, therefore, aimed to investigate whether the mediating effect of mental disorder (depression and anxiety) on the association between bullying victimization, and self-harm and suicidality vary across boys and girls. Methods: Overall, 2522 Australian adolescents aged 12-17-year-olds were analyzed from a nationally representative cross-sectional survey: Young Minds Matter. A series of logistic regressions were employed using Baron and Kenny's approach to test the mediating effect of each mental disorder on the relationship between bullying victimization, and self-harm and suicidality across gender. Further, the Sobel test was used to estimate the indirect effect. Results: Out of 784 (31.1%) bullied victims, 53.2% were girls and 46.8% were boys. A higher proportion of girls compared to boys experienced depression, anxiety, self-harm and suicidality (p < 0.001 for all). The relationships between bullying victimization, and self-harm and suicidality were mediated by depression (p < 0.05) in both boys and girls. While anxiety disorder mediated the association only in girls (p < 0.05). Limitations: Cross-sectional study design does not imply causality. Self-reported data about self-harm and suicidality may be susceptible to social desirability bias. Conclusion: Girls were more affected by bullying, self-harm and suicidality than boys. Depression mediated the correlation between bullying, and self-harm and suicidality in both boys and girls. While anxiety influenced only bullied girls to experience self-harm and suicidality. These findings warrant the need for gender-specific prevention programs to combat bullying and subsequently self-harm and suicidality in adolescents.