Initial posttraumatic urinary cortisol levels predict subsequent PTSD symptoms in motor vehicle accident victims

Background: This study was designed to examine the relationship between urinary hormone levels collected upon admission to the trauma unit following a motor vehicle accident and posttraumatic stress disorder symptomatology 1 month later. Methods: Fifteen-hour urine samples were collected from 63 male and 36 female motor vehicle accident victims and were used to assess levels of catecholamines and cortisol reflecting peritraumatic and acute-phase posttraumatic levels. Presence of posttraumatic stress disorder symptomatology was assessed 1 month after the accident. Results: Motor vehicle accident victims subsequently diagnosed with acute posttraumatic stress disorder excreted significantly lower levels of cortisol in 15-hour urines collected upon admission to the hospital. In addition, urinary levels of cortisol predicted a significant percentage of the variance in intrusive and avoidant thoughts 1 month after the accident. Conclusions: The results of our study suggest that initial cortisol levels in the immediate aftermath of a traumatic event contribute, in part, to subsequent symptoms of posttraumatic stress disorder.