Exposure to potentially traumatic events is fairly common among US adults, yet only a small fraction develops post-traumatic stress disorder (PTSD). It is unclear, however, why some individuals develop PTSD and others do not. Higher pain after a traumatic injury has been associated with higher PTSD symptomology and may be a risk factor for developing PTSD. However, few studies have examined symptoms during the period immediately after a trauma to determine how they relate to PTSD outcome. The goal of this study was to identify trajectories of pain throughout the first month after a traumatic injury and examine their relation to PTSD symptoms at 1 month. A sample of (n = 88) individuals who had experienced a traumatic injury assessed their pain through daily mobile assessments for the first month after injury. Daily mobile assessments consisted of self-report surveys sent to the participants’ mobile device. A follow-up interview was conducted at 1 month after injury to assess PTSD symptomology. Using growth mixture modeling, three trajectories of pain were identified: low pain, decreasing pain, and persistent high pain. Membership to the low pain group was associated with lower PTSD, depression and disability symptoms at 1 month after injury. Membership to the high pain group was associated with higher levels of PTSD, depression and disability symptoms at 1 month. These results demonstrate that there are distinct trajectories of pain after a traumatic injury and these trajectories may relate to later symptoms of psychopathology
