Stress reactivity during short trauma narratives in adolescents with post-traumatic stress disorder (PTSD) and complex PTSD

<b>Background:</b> Psychophysiological dysregulations and negative alterations in cognitions and mood characterize post traumatic stress disorder (PTSD) and complex PTSD (C-PTSD), contributing to an increased risk of disorder persistence and chronic health problems. However, understanding the differences in physiological stress reactivity and negative cognitive-emotional patterns between adolescents with PTSD and C-PTSD remains a notable research gap.<b>Objective:</b> This study examined group differences in autonomic nervous system (ANS) reactivity during the sharing of a short trauma narrative, including resting and recovery phases, and compared subjective experiences of stress, shame, and guilt among adolescents with PTSD, C-PTSD, and trauma-exposed controls.<b>Methods:</b> In a repeated-measures design, 52 adolescents (14-18 years) with PTSD (<i>n</i> = 17), C-PTSD (<i>n</i> = 18), and a control group (<i>n</i> = 17) were assessed for heart rate, heart rate variability, and subjective experiences of stress, shame, and guilt during a standardized trauma interview, as well as during baseline and recovery phases.<b>Results:</b> Linear mixed-effects models revealed a significant interaction between group and time point (<i>F</i> = 4.134, <i>p</i> < .001). The C-PTSD group exhibited a significantly higher heart rate in the recovery phase compared to the PTSD (<i>p</i> = .010) and control groups (<i>p</i> = .036), alongside significantly higher subjective stress, guilt, and shame experiences. Main effects of group were identified for perceived stress (<i>F</i> = 7.543, <i>p</i> = .002), guilt (<i>F</i> = 21.779, <i>p</i> < .001), and shame (<i>F</i> = 19.309, <i>p</i> < .001), with the C-PTSD group exhibiting higher levels compared to PTSD and control groups across all conditions.<b>Conclusions:</b> Prolonged stress responses and elevated experiences of shame and guilt in adolescents with C-PTSD align with the diagnostic criteria of affective dysregulation and negative self-concept. Objective stress measures during trauma interviews may support the diagnosis of C-PTSD. Findings highlight the importance of phase-based trauma therapies that target emotional dysregulation, shame, and guilt.