Psychological Mediators of Avoidance and Endurance Behavior After Concussion

Objective: The avoidance-endurance model (AEM) proposes multiple pathways from acute to chronic pain, with distinct cognitive and behavioral components in each pathway. The AEM may also be applicable to persistent symptoms after concussion. In this study, we tested the AEM as an explanatory framework for concussion outcomes, by using mediation analyses through the proposed psychological mechanisms. Based on the AEM, we hypothesized that postconcussion symptoms would significantly predict avoidance behavior through catastrophizing, and endurance behavior through thought suppression and self-distraction. Participants and Methods: We recruited 84 adults seeking treatment at 2 outpatient concussion clinics (M = 41.8 years old, 63% female) who completed measures of postconcussion symptoms, catastrophizing, thought suppression, "self-distraction" (Five Factor Mindfulness Questionnaire "Act with Awareness" Scale reverse-scored), avoidance behavior, and endurance behavior at an average of 17.8 weeks postconcussion. We conducted 3 mediation analyses to assess each of the AEM pathways. Results: We found a significant indirect effect of postconcussion symptoms on avoidance behavior through catastrophizing (ab = .113 (.036), 95% CI [.053, .195]). The indirect effects of postconcussion symptoms on endurance behavior through thought suppression (ab = .011 (.012), 90% CI [.002, .035]) and "self-distraction" (ab = .003 (.009), 90% CI [.008, .022]) were not statistically significant. Conclusions: Results supported the catastrophizing-avoidance pathway in concussion, but not the thought-suppression-endurance or self-distraction-endurance pathways. Therefore, catastrophic thinking about concussion symptoms may be an appropriate treatment target for individuals who exhibit fear-avoidance behavior. Further research is needed to establish whether thought suppression and self-distraction are relevant for interventions aimed at reducing excessive endurance behavior. Impact and Implications This study evaluated a novel theoretical model of persistent symptoms after concussion. For individuals who exhibit avoidance behavior after concussion, catastrophic thinking about symptoms may be a worthwhile intervention target. Psychological interventions for chronic pain might also be suitable for persistent symptoms after concussion.