Mechanisms of change in posttraumatic headache–related disability: A mediation model

Objective: To explore whether the association between change in headache management self-efficacy and posttraumatic headache–related disability is partially mediated by a change in anxiety symptom severity. Background: Many cognitive–behavioral therapy treatments for headache emphasize stress management, which includes anxiety management strategies; however, little is currently known about mechanisms of change in posttraumatic headache–related disability. Increasing our understanding of mechanisms could lead to improvements in treatments for these debilitating headaches. Methods: This study is a secondary analysis of veterans (N = 193) recruited to participate in a randomized clinical trial of cognitive–behavioral therapy, cognitive processing therapy, or treatment as usual for persistent posttraumatic headache. The direct relationship between headache management self-efficacy and headache-related disability, along with partial mediation through change in anxiety symptoms was tested. Results: The mediated latent change direct, mediated, and total pathways were statistically significant. The path analysis supported a significant direct pathway between headache management self-efficacy and headache-related disability (b = −0.45, p < 0.001; 95% confidence interval [CI: −0.58, −0.33]). The total effect of change of headache management self-efficacy scores on change in Headache Impact Test-6 scores was significant with a moderate-to-strong effect (b = −0.57, p = 0.001; 95% CI [−0.73, −0.41]). There was also an indirect effect through anxiety symptom severity change (b = −0.12, p = 0.003; 95% CI [−0.20, −0.04]). Conclusions: In this study, most of the improvements in headache-related disability were related to increased headache management self-efficacy with mediation occurring through change in anxiety. This indicates that headache management self-efficacy is a likely mechanism of change of posttraumatic headache–related disability with decreases in anxiety explaining part of the improvement in headache-related disability.