Association between Dissociative Symptoms and Morning Cortisol Levels in Patients with Post-traumatic Stress Disorder

Objective Patients with post-traumatic stress disorder (PTSD) showed inconsistencies in their cortisol level, an index of the hypothalamic-pituitary-adrenal axis function. This study examined the relationship between dissociation, childhood trauma, and morning cortisol levels in PTSD patients. Methods This study included 69 (23 males and 46 females) patients and 82 (22 males and 60 females) healthy controls (HCs). Clinical assessments, including the Childhood Trauma Questionnaire (CTQ) and Peri-traumatic Dissociative Experiences Questionnaire scores, and morning cortisol levels were evaluated. The morning cortisol levels were compared between PTSD with high dissociation and low dissociation (PTSD-LD) groups. The effect of CTQ subtype on morning cortisol levels was analyzed. Results The PTSD with high dissociation group showed significantly lower cortisol levels than that of the PTSD-LD and HC groups. A significant inverse correlation was found between cortisol levels and dissociation. A significant positive correlation was found between dissociation and physical abuse and sexual abuse scores. Morning cortisol levels showed a significant positive correlation with emotional abuse, emotional neglect, and physical neglect, respectively. There was no moderating or mediating effect of CTQ on the relationship between cortisol level and dissociation. Conclusion These findings suggest that dissociation is a significant factor related to hypocortisolism in PTSD patients. Additionally, basal morning cortisol levels and dissociation scores were closely associated with childhood trauma.