The Relationship Between Dissociation and Complex Post-Traumatic Stress Disorder: A Scoping Review.

Complex post-traumatic stress disorder (CPTSD) has recently been recognized as an official psychiatric diagnosis in ICD-11, after years of research and advocacy in the field. It has been suggested that dissociative symptoms are a major feature of CPTSD. This scoping review aimed to summarize the existing knowledge base on the relationship between dissociation and CPTSD, and to identify relevant research gaps. We searched the two largest and most widely used academic databases (i.e., the Web of Science and Scopus databases) and the ProQuest database and identified original studies published in English relevant to our research questions, namely: (1) Would CPTSD be associated with dissociative symptoms? 2) How common are dissociative symptoms among people with CPTSD? (3) What are the correlates of dissociative symptoms among people with CPTSD? In all, 26 studies were included. We found 10 studies which reported that people with CPTSD scored significantly higher on a dissociation measure than those without CPTSD, and 11 studies reported a positive correlation between CPTSD symptoms and psychoform/somatoform dissociation scores. While very few studies reported the prevalence and correlates of dissociative symptoms among people with CPTSD, there may be a considerable subgroup of people with CPTSD who have clinically significant levels of dissociative symptoms (e.g., 28.6-76.9%). Dissociation may also be associated with other comorbidities (e.g., DSM-IV Axis II features, shame, somatic symptoms) in people with CPTSD. We recommend that more studies are needed to investigate the prevalence of dissociative symptoms among people with CPTSD and examine how these symptoms are associated with other comorbid conditions and clinical needs in this vulnerable group.