Prevalence and predictors of acute stress disorder and PTSD following road traffic accidents: Thought control strategies and social support

The study examined the prevalence of acute stress disorder (ASD) and post-traumatic stress disorder (PTSD) following road traffic accidents (RTAs), and cross-sectional and prospective relationships with thought-control strategies and perceived social support and criticism from a key significant other. Four hundred and thirty-four consecutive admissions to accident and emergency clinics following an RTA were assessed within 4 weeks of the accident, and 265 reassessed within 6 months. Twenty-one percent met symptom criteria for ASD at initial assessment, and 23% met criteria for PTSD at 4 to 6 months post-accident. These results agree closely with other studies recruiting similar populations in a similar manner. Subjects classified as suffering ASD at initial assessment were 20 times (odds ratio = 20.04) more likely to be classified as suffering PTSD at follow-up. Of the ASD cases assessed at Time 1, 72% were PTSD cases at Time 2. Loss, individual differences in thought-control strategies, and perceived negative quality of social support independently predicted ASD at Time 1 and PTSD at Time 2 in cross-sectional analyses. Analysis of prospective predictors of PTSD at Time 2 indicated that ASD at Time 1, the use of worry to control thoughts at Time 1, a change in perceived social support from Time 1 to Time 2, and an interaction between perceived social support and the use of social control as a coping strategy at Time 1 significantly predicted subsequent PTSD. Those who rated highly on the use of social control and on perceived negative social support had greater probability of subsequently developing PTSD (odds ratio = 8.2). The results were mainly as predicted and conform to models of trauma in which persistent disorders are associated with inhibition of emotional processing.