Obsessive-Compulsive Disorder, Trauma, and Stress: A Network Approach

Experience of traumatic life events (TLEs) has consistently been identified as a risk factor that can trigger and exacerbate obsessive compulsive symptoms (OCS). At the clinical level of severity, OCD and post-traumatic stress disorder (PTSD) are also highly comorbid at rates greater than in the general population. However, much remains unclear about the differential interrelations between symptoms of OCD and PTSD, as well as the influence of a traumatic history on the connectedness of hallmark features of OCD. The overarching study applied network analysis – a recently developed tool that can help shed light on symptom structure and relations – to examine OCD, traumatic events, and PTSD from two separate but complementary perspectives. With a sample of individuals with lifetime OCD, Study 1 took first steps to examine the structure of OCD as measured by symptom dimensions in conjunction with obsessions and compulsions severity. Findings highlighted aggressive, sexual, religious obsessions and checking compulsions as a central component through which other OCD features are connected. It also provided qualitative evidence of a more densely connected network of OCD components in those with a trauma history, in support of TLEs as an important vulnerability factor for OCD. Study 2 expanded upon these findings with a separate sample of treatment-seeking OCD individuals, investigating symptom-level relationships between the heterogeneous syndromes of OCD and PTSD. As clinical correlates, anxiety and depression were not found to explain any symptom overlap between OCD and PTSD, which were found to form more independent symptom constellations than expected. Interestingly, OCD nodes were found to form two clusters of a) control/resistance and b) time occupied, interference, and distress; meanwhile, re-experiencing symptoms were highlighted as the central PTSD symptom type. Overall, findings illustrate the utility of the network approach in studying psychopathology, and point towards mechanistic links between symptoms that may be important to target in clinical interventions for trauma and OCD.