PTSD as a Mediator in the Relationship Between Post-Concussive Symptoms and Pain Among OEF/OIF/OND Veterans

Traumatic brain injury (TBI), pain, and post-traumatic stress disorder (PTSD) commonly co-occur in Veteran populations, particularly among Veterans returning from the recent conflicts in Iraq and Afghanistan. Extant research indicates that both TBI and PTSD can negatively impact pain broadly; however, less is known about how these variables impact one another. The current study examines the impact of self-reported post-concussive symptoms on both pain severity and pain interference among Veterans with PTSD who screened positive for a possible TBI, and subsequently, evaluates the potential mediating role of PTSD in these relationships.

Participants were 126 combat Veterans that served in Operation Enduring Freedom, Operation Iraqi Freedom, or Operation New Dawn who were being evaluated for participation in a multisite treatment outcomes study. As part of an initial evaluation for inclusion in the study, participants completed several self-report measures and interviews, including the Brief Traumatic Brain Injury Screen, Neurobehavioral Symptom Inventory, Brief Pain Inventory, and the Clinician Administered PTSD Scale, which were utilized in these analyses.

For pain severity, greater post-concussive symptoms significantly predicted increased pain severity with a significant indirect effect of post-concussive symptoms on pain severity through PTSD (indirect effect = 0.03; 95% confidence interval = 0.0094-0.0526). Similar results were found for pain interference (indirect effect = 0.03; 95% confidence interval = 0.0075-0.0471).

These findings replicate and extend previous findings regarding the relationship between TBI, pain, and PTSD. Self-reported post-concussive symptoms negatively impact both pain severity and pain interference among Veterans with probable TBI, and PTSD serves as a mediator in these relationships. Clinically, these results highlight the importance of fully assessing for PTSD symptoms in Veterans with a history of TBI presenting with pain. Further, it is possible that providing effective PTSD treatment to reduce PTSD severity may provide some benefit in reducing post-concussive and pain symptoms.