Acute stress disorder and posttraumatic stress disorder symptoms among patients severely injured in motor vehicle accidents in Japan

Objective: The prevalence of acute stress disorder (ASD) and posttraumatic stress disorder (PTSD) in seriously injured survivors of motor vehicle accidents (MVAs) in Japan was investigated. Furthermore, predictive factors in the early stage for development of PTSD were evaluated. Method: Subjects were consecutive samples (N=100) of patients hospitalized with severe MVA injuries surveyed at two time points: within 1 month after the MVA and then 6 months later. In the first survey, we conducted the Acute Stress Disorder Interview and compiled results of a self-rating questionnaire; in the second survey, we conducted a structured clinical interview via telephone. Results: The prevalence of ASD and PTSD were 9.0% and 8.5%, respectively. The shift from ASD to PTSD was more pronounced when we included partial diagnoses of ASD and PTSD. Three predictive factors for PTSD were identified through multiple logistic analysis: ASD-positive, presence of persistent physical disability and physical injury severity. Conclusions: Even among severely injured MVA survivors, most acute stress symptoms subside over time. However, having ASD or partial ASD in the early stage, and the presence of physical disability as an aftereffect are strong predictive factors for PTSD. These findings validate the importance of evidence-based intervention for ASD to forestall PTSD.