Post-Traumatic Stress, Illness Perception, Concussion Symptoms, and Quality of Life Following Mild Traumatic Brain Injury

Background Working-age individuals with mild traumatic brain injury (mTBI) often experience persistent post-concussion symptoms (PCS) that significantly impair their quality of life (QoL). Post-traumatic stress disorder (PTSD) may act as a psychological mechanism linking PCS to a poorer QoL, while illness perception may influence the extent to which PCS lead to PTSD; these relationships have not been tested. Establishing this moderated mediation pathway is critical for identifying patients at heightened psychological risk and informing early intervention strategies to optimize post-acute rehabilitation outcomes. Objective This study examined the mediating role of PTSD in the relationship between PCS and QoL, as well as the moderating effect of illness perception on these associations. Methods A longitudinal study was conducted among 120 working-age individuals with mTBI in Indonesia. PCS and illness perception were assessed at discharge, PTSD was measured at 1 month, and QoL was measured at 3 months post-discharge. A moderated mediation analysis was performed using Hayes’ macro–PROCESS Model 7. Results PCS at discharge were associated with poorer QoL at 3 months, with PTSD fully mediating this relationship. Illness perception moderated the effect of PCS on PTSD, with more negative perceptions intensifying symptoms. The indirect effect of PCS on QoL through PTSD was stronger among individuals prone to negative illness perception. Discussion PTSD plays a critical role in mediating the relationship between PCS and QoL, while negative illness perception further amplifies this indirect effect, leading to a poorer QoL 3 months post-injury. These findings confirm the presence of a moderated mediation pathway, highlighting the need for early psychological screening and targeted interventions that address both PTSD and negative illness perception. Integrating these strategies into post-acute rehabilitation may improve long-term recovery outcomes in working-age individuals with mTBI.