Résumé
Background: chronic pain is a disabling condition often described by the biopsychosocial model. Among the underlying psychological factors, dissociation may participate in the pain modulation, although it is still little studied. In this thesis, I present a literature review and a research protocol exploring the relationship between dissociation and chronic pain. Objective: the review aims to evaluate (1) the association between the occurence of dissociative symptoms and the diagnosis of chronic pain, (2) the correlation between the level of dissociation and pain intensity, and (3) the influence of psychiatric comorbidities on this relationship. The aim of the observational study is to investigate this relationship in subjects with a particular vulnerability for dissociation. Method: a systematic search was conducted using the following MeSH terms: “dissociative symptoms”; “dissociative reaction”; “depersonalization”; “derealization”; “dissociation”; “chronic pains”; “chronic headache”. Only original articles on adult subjects written in English were included. Subjects with chronic pain and either borderline personality disorder or PNES were included in the observational cross-sectional study. They completed the BPI, DES, HADS, PCL-5 and CTQ questionnaires. Results: of the 17 studies included, 12 found a positive association between dissociation and chronic pain. 5 studies involving subjects with fibromyalgia or a history of trauma found a positive correlation between the level of dissociation and pain intensity. Comorbid diagnoses of anxiety, depression, PTSD, and traumatic history, were more frequent in subjects with chronic pain and were positively associated with the level of dissociation. Conclusion: this review shows that dissociative symptoms and chronic pain are interdependent, and that common psychiatric comorbidities may influence their relationship. These findings underline the need to systematically assess dissociation in this population, in order to propose personalized treatment options.