The mediating role of family functioning between childhood trauma and depression severity in major depressive disorder and bipolar disorder

Background

Childhood trauma (CT) and family functioning exert significant influences on the course and long-term outcome of major depressive disorder (MDD) and bipolar disorder (BD) patients. Hence, we examined the intricate relationship between CT, family function, and the severity of depressive episodes in MDD and BD patients.

Methods

562 patients with depressive episodes (336 MDD and 226 BD) and 204 healthy controls (HCs) were included in this retrospective study. The 17-item Hamilton Depression Rating Scale (HAMD-17), Childhood Trauma Questionnaire (CTQ), and Family Adaptability and Cohesion Evaluation Scale (FACES II-CV) were assessed. Pearson correlation analysis and mediation analysis were performed.

Results

CT had both a direct and indirect impact on depression severity in MDD and BD groups. In MDD, family adaptability mediated the impact of all CT subtypes on depression severity (Effect = 0.113, [0.030, 0.208]). In BD, family cohesion played a mediating role between emotional neglect (EN) and HAMD-17 scores (Effect = 0.169, [0.008, 0.344]). Notable differences were observed in onset age, illness duration, episode frequency, family history, and CT subtypes between MDD and BD (P < 0.05).

Limitations

This study has several limitations including recall bias, lack of objective family functioning measures, small sample size, and cross-sectional design.

Conclusions

Family functioning mediated the impact of CT on depressive symptoms severity in MDD and BD patients. MDD patients with a history of CT exhibited reduced family adaptability, while BD patients with a history of EN had weaker familial emotional bonds. Our findings highlighted the importance of family-focused preventive interventions in mitigating the long-term effects of CT.