(PS7-B47) Linking PTSD and OCD: A Network Approach

Background: Posttraumatic stress disorder (PTSD) and obsessive-compulsive disorder (OCD) often co-occur, resulting in increased impairment and poorer treatment outcomes. Conceptual models of this comorbidity highlight that PTSD and OCD symptoms overlap in both their form and function. In line with this conceptualization, the network theory of mental disorders posits that functional relationships between symptoms contribute to the maintenance and co-occurrence of psychological conditions. Despite the relevance of network theory to conceptualizations of PTSD and OCD comorbidity, no empirical studies have used this approach. The present study thus sought to address this gap by using a network approach to examine co-occurring PTSD and OCD symptoms in a clinical sample.

Methods: Treatment-seeking adults (N = 146) diagnosed with both OCD and PTSD completed the Yale-Brown Obsessive Compulsive Scale (YBOCS) and Posttraumatic Stress Disorder Checklist for DSM-5 (PCL-5) prior to treatment initiation. Confirmatory factor analysis (CFA) was used to identify the optimal factor structure prior to network analysis. Network metrices, fit statistics, and bridge statistics were computed for the best fitting factor solution.

Results: Consistent with prior findings, solutions that modelled OCD and PTSD as comorbid, rather than combined, constructs better fit the data (Pinciotti et al, 2022). Additionally, the 7-factor solution for the PCL-5 provided better fit than the 4-factor DSM-5 solution. Accordingly, a network was computed with 2 nodes for OCD (obsessions, compulsions) and 7 nodes for PTSD (intrusions, avoidance, negative affect, anhedonia, externalizing behavior, anxious arousal, and dysphoric arousal). Fit statistics suggested adequate stability for edge and strength centrality estimates. Network findings demonstrated inter-associations among OCD and PTSD symptoms. The strongest links were observed between (1) obsessions and compulsions, and (2) trauma-related intrusions and avoidance, and these associations were significantly stronger than all other relationships observed. Interestingly, no direct links were observed between obsessions/compulsions and trauma-related intrusions/avoidance. Rather, affective nodes connected these sets of symptoms. Accordingly, the nodes with greatest bridge centrality were obsessions, dysphoric arousal, and anhedonia.

Conclusions: Our results extend prior findings on the structure of PTSD-OCD comorbidity and suggest that overlapping affective processes play a role in linking PTSD and OCD symptoms. Limitations include the reliance on cross-sectional data and a relatively small sample given our analytic approach. Implications for conceptual models and clinical research on OCD-PTSD comorbidity will be discussed.