Longitudinal associations between complex posttraumatic stress disorder and depressive symptoms: A four-wave study among de facto unattended children in China.

Complex posttraumatic stress disorder (CPTSD) typically occurs following long-term, repeated trauma and involves two distinct symptom clusters: posttraumatic stress disorder (PTSD) and disturbances in self-organization (DSO). CPTSD is widely comorbid with depression, but the mechanism of mutual influence at the within-person level remains unclear. De facto unattended children in China are children whose parents are deceased, missing, imprisoned, or severely disabled/chronically ill, or who have one such parent while the other is likewise unable to provide care, leaving them without effective guardianship. These children widely suffer from CPTSD and depressive symptoms. This study collected 4-wave data from 250 de facto unattended children over 2 years and conducted a random intercept cross-lagged panel model (RI-CLPM) to explore the longitudinal relationship between depressive symptoms, PTSD, and DSO symptoms. Results indicated that all measures of PTSD, DSO, and depressive symptoms exhibit adequate longitudinal measurement invariance. Depressive symptoms were significantly longitudinally associated with both PTSD and DSO symptoms, with a stronger association with DSO. Additionally, DSO symptoms were also significantly longitudinally associated with depressive symptoms from T2 to T4. Our study suggests that depression may predict the development of CPTSD among children. Furthermore, DSO, especially the affective dysregulation dimension, may contribute to maintaining comorbidity. Clinically, prioritizing depressive symptoms and DSO may improve the effectiveness of interventions for comorbid depression and CPTSD.