Mild traumatic brain injury increases risk for the development of posttraumatic stress disorder

BACKGROUND Traumatic brain injury (TBI) and posttraumatic stress disorder (PTSD) occur in individuals who sustain physical injury and share a significant overlap in symptoms. PTSD rates in the civilian injury population range from 20% to 40%. The current study examined the presence of PTSD symptoms at multiple time points (3 months and 6 months after injury) among individuals with and without TBI after admission to a Level I trauma center. METHODS This prospective cohort study included patients 18 years and older admitted to a Level I trauma center for 24 hours or greater. Demographic and injury-related data were gathered in addition to assessments of PTSD during initial hospitalization after injury, as well as 3 months and 6 months later. The Primary Care PTSD Screen and PTSD Checklist-Civilian version were used to determine probable PTSD. International Classification of Diseases, 9th Rev. codes were used to determine mild TBI (MTBI). RESULTS A total of 494 patients were enrolled at baseline, 311 (63%) completed 3-month follow-up, and 231 (47%) completed 6-month follow-up at the time of analysis. Preinjury PTSD was reported by 7% of the participants. At 3 months, patients with MTBI evidenced a probable PTSD rate of 18%, compared with a rate of 9% for patients with no MTBI (p = 0.04), although this relationship became a nonsignificant trend (p = 0.06) when demographics were included. At 6 months, patients with MTBI evidenced a probable PTSD rate of 26%, compared with a rate of 15% for patients with no MTBI (p = 0.04), and this relationship remained significant when demographics were included. Preinjury history of TBI did not predict PTSD, but incidence of TBI for the injury in which they were hospitalized did predict PTSD. CONCLUSION TBI at time of injury demonstrated a nonsignificant trend toward higher rates of PTSD at 3 months and significantly predicted PTSD at 6 months after injury. This important finding may help clinicians identify patients at high risk for PTSD after injury and target these patients for screening, intervention, and referral for treatment. LEVEL OF EVIDENCE Prognostic study, level III.