Associations between childhood trauma and heart rate variability: Serial mediation by alexithymia and anxiety symptoms.
PURPOSE Childhood trauma has been associated with long-term alterations in psychological functioning and autonomic regulation. However, the psychological processes linking early adverse experiences with individual differences in autonomic function remain insufficiently understood. The present study examined the associations between childhood trauma and heart rate variability (HRV), with particular attention to the potential mediating roles of alexithymia and anxiety symptoms. PARTICIPANTS AND METHODS A total of 152 university students (mean age = 22.19 years, SD = 1.63) participated in this cross-sectional study. Childhood trauma was assessed using the Revised Adverse Childhood Experience Questionnaire, alexithymia was measured using the Toronto Alexithymia Scale-20, and anxiety symptoms were evaluated using the Beck Anxiety Inventory. Heart rate variability was indexed by the root mean square of successive differences (RMSSD) derived from electrocardiogram recordings. Serial mediation analyses were conducted using the PROCESS macro (Model 6) with bootstrap resampling to examine the indirect associations among the study variables. RESULTS Childhood trauma was positively associated with alexithymia and anxiety symptoms and negatively associated with HRV. Alexithymia and anxiety symptoms were both negatively correlated with HRV and positively correlated with each other. Serial mediation analysis indicated that alexithymia and anxiety symptoms were statistically associated with the relationship between childhood trauma and HRV through both independent and sequential indirect pathways. CONCLUSION The findings suggest that higher levels of childhood trauma are associated with lower heart rate variability primarily in conjunction with elevated alexithymia and anxiety symptoms. Within a cross-sectional associational framework, alexithymia and anxiety may represent psychological characteristics linked to both early adverse experiences and variations in autonomic regulation. These results highlight the interconnected nature of emotional awareness, affective distress, and physiological regulation, and underscore the importance of considering emotional processing traits when examining psychophysiological correlates of childhood trauma.