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.