PTSD and chronic pain: A systematic review and meta-analysis of mediation studies

Post-Traumatic Stress Disorder (PTSD) and chronic pain frequently co-occur and are known to mutually exacerbate one another, yet, the mechanisms connecting PTSD to chronic pain are less clear. The purpose of this systematic review and meta-analysis was to identify and quantify psychosocial factors that mediate the bidirectional relationship between PTSD and chronic pain. Five databases (PubMed, Cochrane Central Register of Controlled Trials, CINAHL Complete, PsychINFO, and Web of Science) were searched from inception through December 17th 2024. Mediation studies which examined the relationship between PTSD and pain severity or physical interference among adults with chronic pain were included. Standardized indirect regression coefficients (β) were pooled and served as the primary outcome. Of the 5359 articles identified, 14 studies met inclusion criteria. Pain catastrophizing mediated the relationship between PTSD and pain severity (K = 3; β =.18, 95% CI:.12,.26) while depression mediated the relationship between PTSD and physical interference (K = 3; β = 1.25, 95% CI:.04, 2.46) but not pain severity (K = 4; β =.18, 95% CI: -.10,.47). These results should be interpreted with caution as all identified studies were cross-sectional and their methodological quality was low. More methodically rigorous longitudinal studies are needed to better understand the putative mechanisms connecting PTSD to chronic pain. PROTOCOL REGISTRATION: PROSPERO#: CRD42024608251 PERSPECTIVE: This systematic review and meta-analysis examined psychosocial mechanisms that explain the bidirectional relationship between PTSD and chronic pain. There was preliminary evidence that PTSD is indirectly associated with chronic pain via pain catastrophizing and depression. Additional longitudinal research is needed to increase our understanding of putative mechanisms connecting both conditions.