Childhood trauma, poor sleep quality, anhedonia, and alexithymia in patients with depression: A cross-sectional serial mediation analysis.

BACKGROUND: Childhood trauma, poor sleep quality, anhedonia, and alexithymia are closely associated in patients with depression; however, the interrelationships among these factors remain insufficiently understood. This study examined whether poor sleep quality and anhedonia statistically mediated the association between childhood trauma and alexithymia in patients with depression. METHODS: In this cross-sectional study, 269 patients with depression completed the Childhood Trauma Questionnaire (CTQ), Pittsburgh Sleep Quality Index (PSQI), Snaith-Hamilton Pleasure Scale (SHAPS), and 20-item Toronto Alexithymia Scale (TAS-20). Serial mediation analysis was conducted using PROCESS Model 6 with 5000 bootstrap resamples to estimate the indirect associations of childhood trauma with alexithymia through poor sleep quality and anhedonia. RESULTS: Childhood trauma was positively associated with poorer sleep quality (β = 0.395), and poorer sleep quality was positively associated with more severe anhedonia (β = 0.385). In turn, poorer sleep quality (β = 0.176) and more severe anhedonia (β = 0.392) were positively associated with greater alexithymia (all P < 0.001). The indirect association between childhood trauma and alexithymia was significant through PSQI score (Effect = 0.077, 95% CI [0.024, 0.137]), through SHAPS score (Effect = 0.102, 95% CI [0.043, 0.168]), and through the serial pathway involving PSQI and SHAPS score (Effect = 0.066, 95% CI [0.036, 0.105]). Collectively, these indirect associations accounted for 75.38% of the total association. The direct association between childhood trauma and alexithymia was not statistically significant (Effect = 0.080, 95% CI [-0.044, 0.203]). CONCLUSION: These cross-sectional findings suggest a possible serial indirect-association pattern in which childhood trauma is associated with alexithymia through poorer sleep quality and greater anhedonia. Clinicians may consider jointly assessing these symptoms in patients with depression with a history of childhood trauma. Longitudinal and intervention studies are needed to clarify causality.