Longitudinal Cross‐Lagged Relationships of Complex Post‐Traumatic Stress Disorder, Depression, and Anxiety Among Adolescents and Emerging Adults With Childhood Bullying Victimization Experiences

<b>Background:</b> Individuals who have experienced bullying victimization often develop symptoms of complex post-traumatic stress disorder (CPTSD), depression, and anxiety, with these symptoms mutually influencing one another. This study aims to explore the reciprocal relationships between CPTSD, depression, and anxiety among adolescents and emerging adults who have experienced childhood bullying victimization, from both variable-level and symptom-level perspectives. <b>Method:</b> A total of 3945 adolescents and 2726 emerging adults with childhood bullying victimization experiences were measured 6-month interval in the study. All the participants completed the questionnaires assessing for bullying victimization, CPTSD, depression, and anxiety. The data were analyzed using cross-lagged panel analysis and cross-lagged network analysis. <b>Results:</b> The cross-lagged panel analysis reveals that CPTSD more strongly and consistently predicts depression and anxiety, whereas the reverse influence is weaker across both groups. At the symptom level, for adolescents, "death" (in depression) influences "feel worthless" (in CPTSD) and "feel like a failure" (in CPTSD). Additionally, "death" (in depression) is more likely to predict subsequent symptoms, while "feel like a failure" (in CPTSD) is more frequently activated by other symptoms. In the emerging adults, some strong cross-lagged effects were observed, such as "motor" (in depression) to "traumatic dreams" (in CPTSD) and "worthless" (in depression) to "feel like a failure" (in CPTSD). In addition, "exaggerated startle" (in CPTSD) tends to predict symptoms, while "feel like a failure" (in CPTSD) is more frequently activated. <b>Conclusions:</b> Findings suggested that interventions alleviating "death" (in depression) among adolescents and "exaggerated startle" (in CPTSD) among emerging adults may improve overall mental health.