The mediating effect of alexithymia between childhood trauma and negative symptoms in chronic schizophrenia

Evidence suggests that childhood trauma (CT) increases the risk of schizophrenia (SZ) and influences symptom type and severity. However, the link between CT and negative symptoms (NS) has not been fully explored. This study investigated the relationship between CT and NS in SZ, while considering the mediating effect of alexithymia. We enrolled 94 patients with chronic schizophrenia (CS) and 105 age- and sex-matched healthy controls (HCs) from Tianjin Anding Hospital. CT was assessed using the Childhood Trauma Questionnaire (CTQ), psychopathology with the Positive and Negative Syndrome Scale and alexithymia with the 20-item Toronto Alexithymia Scale. Structural equation modeling was used to test the mediation model. CT was reported by 70.1% of patients versus 32.7% of HCs. In patients with SZ, CTQ scores were positively correlated with NS (r = 0.30, p = 0.003). Alexithymia was observed in 18.1% of patients and 7.6% of HCs, and it was positively correlated with NS (r = 0.35, p = 0.001). Two factors of alexithymia-difficulty identifying feelings (95% CI [0.002, 0.085]) and externally oriented thinking (95% CI [0.002, 0.060])-mediated the relationship between CT and NS. These findings suggest that reducing alexithymia may help alleviate NS in SZ.