Acute stress disorder, subsequent posttraumatic stress disorder and depression after a series of typhoons

From August to November 1992, five typhoons struck the U.S. Pacific island territory of Guam. Three hundred and twenty subjects exposed to all five typhoons participated in a population survey measuring their acute stress symptoms and subsequent diagnoses of posttraumatic stress disorder (PTSD) and depression. A 23-item scale approximating the new DSM-IV diagnosis of acute stress disorder (ASD) was used to classify subjects into three groups based on their symptoms one week after the first typhoon: (1) probable ASD, (2) an early traumatic stress response (ETSR) of fear, intrusion, avoidance, and arousal, without dissociation, and (3) no acute diagnosis. A multi-dimensional measure of PTSD and the Zung Self-Rating Depression Scale were used to assess PTSD and depression 8 months after the first storm. The point prevalence of ASD at one week was 7.2%. An additional 15% of subjects had ETSR. Subjects with probable ASD at one week had significantly increased rates of PTSD and somewhat higher rates of depression at 8 months than those without ASD. In contrast, subjects with ETSR at one week did not have a poorer outcome than those with no acute diagnosis. These findings suggest that ASD is prognostically important, but also indicate that all acute stress symptoms do not have the same discriminative value. In this study, the acute dissociative symptoms of emotional numbing and derealization differentiated highly symptomatic subjects at risk for subsequent psychopathology (ASD) from others who were highly symptomatic at one week, but then had a more benign, posttraumatic course (ETSR).