A substantial minority of children experience post-traumatic stress symptoms (PTSS) following injury. Research indicates variation in the trajectory of PTSS following pediatric injury, but investigation of PTSS following concussion has assumed homogeneity. This study aimed to identify differential trajectories of PTSS following pediatric concussion and to investigate risk factors, including acute post-concussive symptoms (PCS), associated with these trajectories. A total of 120 children ages 8-18 years reported PTSS for 3 months following concussion diagnosis using the Child PTSD Symptom Scale, with a score of 16 or above indicating probable post-traumatic stress disorder diagnosis. Age, gender, injury mechanism, loss of consciousness, previous concussions, prior hospitalization, prior diagnosis of depression or anxiety, and acute PCS were assessed as risk factors. Data were analyzed using group-based trajectory modeling. Results revealed 16% of children had clinically significant PTSS 2 weeks post-concussion, declining to 10% at 1 month and 6% at 3 months post-injury. Group-based trajectory modeling identified three trajectories of PTSS post-concussion: "resilient" (70%); "recovering" (25%), in which children experienced elevated acute symptoms that declined over time; and "chronic symptomatology" (5%). Due to small size, the chronic group should be interpreted with caution. Higher acute PCS and prior diagnosis of depression or anxiety both significantly increased predicted probability of recovering trajectory group membership. These findings establish that most children are resilient to PTSS following concussion, but that PTSS do occur acutely in a substantial minority of children. The study indicates mental health factors, particularly PTSS, depression, and anxiety, should be considered integral to models of concussion management and treatment.
Keywords: concussion; group-based trajectory modeling; mild traumatic brain injury; pediatrics; post-traumatic stress.