The mediating role of post-traumatic stress disorder symptoms in the relationship between childhood adversities and depressive symptoms in two samples

Background: Childhood adversities have been increasingly recognized as a significant risk factor for depression. However, the underlying mediating mechanism between childhood adversities and depression requires further investigation. The literature shows that childhood adversities are also closely associated with post-traumatic stress disorder (PTSD) symptoms and that PTSD symptoms can predict depressive symptoms. It remains unexplored whether PTSD symptoms can act as a mediator between childhood adversities and depression. Objectives: The primary goal of this study was to examine whether PTSD symptoms would mediate the relationship between childhood adversities and depressive symptoms. Participants and setting: We examined in a convenience sample of Hong Kong adults aged 18 or above (N = 418) whether PTSD symptoms would mediate the relationship between childhood adversities and depressive symptoms. We then examined and compared the results with those in another convenience sample of Chinese-speaking young adults (mainly from Taiwan and Hong Kong) aged between 18 and 24 (N = 205). Participants in both samples completed online surveys that included measures of childhood adversities, PTSD symptoms and depressive symptoms. Results: Childhood adversities were significantly associated with depressive symptoms; and this relationship was mediated by PTSD symptoms in both samples. Conclusion: This study is one of very few studies demonstrating that PTSD symptoms mediate the relationship between childhood adversities and depressive symptoms. Our findings suggest that addressing unresolved PTSD symptoms for adults with childhood adversities may help in preventing or treating depressive symptoms. Therefore, PTSD symptoms should be taken into account in the prevention and management of depression.