Associations of Posttraumatic Stress Disorder Symptom Clusters and Pain Interference in Post-9/11 Veterans: Exploring Sleep Impairment and Physical Activity as Underlying Mechanisms.

Background: Posttraumatic stress disorder (PTSD) symptoms and pain are highly prevalent and comorbid, particularly in veterans, but mechanisms explaining their linkage remain unclear. The aims of this study were to determine: (1) whether sleep impairment and physical activity (PA) mediate relations between PTSD symptoms and pain interference (assessed both longitudinally and as residual change) and (2) the unique roles of each PTSD symptom cluster in those relationships.

Methods: The present study is a secondary analysis of a longitudinal observational investigation of 673 post-9/11 veterans (45.8% women). Surveys were administered at baseline and 3-month and 6-month follow-ups.

Results: PTSD symptoms were significantly associated with pain interference longitudinally and worsening pain interference over time. Sleep impairment, but not PA, significantly mediated the relationship between PTSD symptoms and subsequent pain interference. Hyperarousal symptoms were found to be the primary driver of the relationship between PTSD symptoms and pain interference and re-experiencing symptoms were associated with change in pain interference via sleep impairment. Men and women did not differ on any of the study variables with the exception of PA.

Conclusion: Findings underscore the importance of targeting sleep as a key modifiable health factor linking PTSD symptoms to pain interference in post-9/11 veterans.