Psychological flexibility moderates the influence of fear avoidance on outcomes after mild traumatic brain injury.

Psychological factors contribute to poorer long-term outcomes following mild traumatic brain injury (mTBI); however, the exact psychological mechanisms that underly this relationship are not well understood. This study examined the relationship between psychological flexibility, fear avoidance, and outcomes over the first 6 months after mTBI. Adults with mTBI-completed measures of psychological flexibility, fear avoidance, post-concussion symptoms, and functional status at baseline (<3 months post-injury; N = 152), and 3-month (N = 133) and 6-month follow-up (N = 102). A conceptually derived moderation-mediation analysis was used to test the mediating effect of fear avoidance on post-concussion symptoms and functional outcomes, and the moderating effects of psychological flexibility on fear avoidance. Fear avoidance had a significant indirect effect on the relationship between post-concussion symptoms and functional status across all three time points. Psychological flexibility was found to significantly moderate these effects. Only low levels of psychological flexibility had a significant influence on the mediating effects of high fear avoidance on functional status at 6-month follow-up. Psychological flexibility may influence mTBI recovery by exerting an influence on fear avoidance. These initial findings provide a potential theoretical explanation of how fear avoidance can become maladaptive with time after mTBI.