Abstract
BACKGROUND: Complex post-traumatic stress disorder (CPTSD) is a severely disabling mental health condition, frequently observed in survivors of prolonged, repeated or multiple traumatic stressors. While studies indicate that engaging in psychotherapy can reduce CPTSD symptom severity, data on long-term effectiveness of interventions is scarce. The aim of this study was to evaluate long-term CPTSD trajectories of affected individuals after a 6-week multimodal psychodynamic inpatient rehabilitation treatment. METHODS: In this observational single center study participants completed questionnaires on CPTSD symptoms (ITQ), anxiety, depression, and somatization (BSI-18), functional impairment (WHODAS-12), mentalizing (MZQ-6) and epistemic trust, mistrust and credulity (ETMCQ) before (T1) and at the end of treatment (T2) as well as > 12 months after treatment. Repeated measures analyses of variance (ANOVAs) and reliable change index (RCIs) for the ITQ as primary outcome variable were calculated to evaluate mean symptom change. The influence of a range of potential factors affecting change was evaluated using correlation coefficients and ANOVAs. RESULTS: A total of n = 38 individuals diagnosed with CPTSD completed the questionnaires 14-28 (median: 21.2) months after treatment. Participants reported a significant reduction of CPTSD symptoms with large effect sizes at follow-up (p < 0.001, d = 1.70) as well as reduced symptoms of depression (p = 0.009, d = 0.84) and anxiety (p = 0.009, d = 0.1.24) and improved social participation (p = 0.012, d = 1.06). At follow-up, 59% of participants no longer fulfilled CPTSD criteria. Improved epistemic trust (r = -0.43, p = 0.007), and reduced epistemic credulity (r = 0.44, p = 0.006) were associated with reduced CPTSD symptoms. DISCUSSION: To the authors knowledge, this is the first study to report long-term CPTSD symptom trajectories after psychodynamic inpatient treatment. The results indicate lasting symptom change and identify improvements in epistemic trust as associated with symptom change. Due to the observational nature of the study, no causal attributions as to the effectiveness of the treatment can be drawn.