Which PTSD symptom would mediate the relationship between trauma exposure and depressive symptoms? Preliminary findings from two samples of trauma-exposed middle school students

Recent studies have documented that post-traumatic stress disorder (PTSD) symptoms are robustly associated with depressive symptoms and may mediate the relationship between trauma exposure and depressive symptoms. However, no study has explored the differential mediating effects of four specific PTSD symptom clusters. This study made the first attempt to examine the mediating effects of different PTSD symptom clusters on the linkage between trauma exposure and depressive symptoms. We analyzed data from two large samples of Chinese middle school students (N = 693 and 957) who had experienced the 2013 Ya'an earthquake. Participants completed standardized measures of trauma exposure, PTSD symptoms, and depressive symptoms. The prevalence of probable PTSD was 3.4% and 3.6%, respectively, in the two samples. Mediation analyses revealed that negative alterations in cognitions and mood and alterations in arousal and reactivity were statistically significant mediators in the relationship between trauma exposure during the earthquake and depressive symptoms. The results are very consistent in both samples. The findings suggest that symptom-specific tailored management of these two specific PTSD symptom clusters might have the potential to change the trajectory of developing depressive symptoms among trauma-exposed populations.