Dissociative Subtype of Posttraumatic Stress Disorder or PTSD With Comorbid Dissociative Disorders: Comparative Evaluation of Clinical Profiles

Introduction: The fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (American Psychiatric Association, 2013) introduced a dissociative subtype for patients with posttraumatic stress disorder (PTSD) and depersonalization and/or derealization symptoms. Despite high comorbidity rates between PTSD and dissociative disorders (DDs), research has not paid attention to the differentiation or overlap between the dissociative subtype of PTSD and DDs. This raises a question: To what extent do patients with dissociative PTSD differ from patients with PTSD and comorbid DDs? Method: We compared three groups of complex patients with trauma-related disorders and/or personality disorders (n = 150): a dissociative PTSD, a nondissociative PTSD, and a non-PTSD group of patients with mainly personality disorders. We used structured clinical interviews and self-administered questionnaires on dissociative symptoms and disorders, personality disorders, trauma histories, depression, anxiety, and general psychopathology. The Dissociative Experiences Scale (DES; >= 20) and the depersonalization/ derealization subscale of the DES were used for differentiating dissociative PTSD from nondissociative PTSD. Results: Of all patients, 33% met criteria for dissociative PTSD. More than half of the dissociative PTSD patients (54%) met criteria for one or more DDs; using the depersonalization/derealization subscale of the DES, even 66% had a comorbid DD. But also of the non-PTSD patients, 24% had a mean DES score of >= 20. There were no symptomatic differences (e.g., depression and anxiety) between dissociative PTSD with and without comorbid DDs. Conclusion: Overlap between dissociative PTSD and DD is large and we recommend replication of previous studies, using structured clinical assessment of DDs. Clinical Impact Statement This study suggests that there is substantial overlap between the dissociative subtype of posttraumatic stress disorder (PTSD), which is added to the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders, and dissociative disorders. More than half of the patients who were diagnosed with PTSD met the criteria of dissociative PTSD. Furthermore, approximately half of the patients with dissociative PTSD had (also) a dissociative disorder. This suggests that when diagnosing and treating patients with PTSD, clinicians should be aware of co-morbid (symptoms of) dissociative disorders.