The relationship among hormone levels, amnesia, and post-traumatic stress in motor vehicle accident victims

The literature regarding amnesia and post-traumatic stress reveals disagreement as to whether a trauma victim can subsequently develop post-traumatic stress from an event for which he/she is amnesic. Conflicting results may be attributable to inconsistencies in defining amnesic status. Previous research has suggested that amnesic patients who Nave no memory of the precipitating trauma display different hormone profiles in the immediate aftermath of the event and are less likely to develop subsequent PTSD. The present study examines hormone levels and subsequent ASD and PTSD among amnesic and nonamnesic victims of motor vehicle accidents (MVAs). Initial urinary catecholamines and cortisol and subsequent salivary cortisol levels were assessed in hospitalized MVA victims. Participants were evaluated for ASD symptoms two weeks following the accident and PTSD symptoms six weeks post-accident. Amnesic patients displayed lower initial cortisol levels, and higher morning salivary cortisol levels and greater difference between morning and evening levels compared to nonamnesics two weeks following the accident. Furthermore, amnesics demonstrated lower incidence of PTSD at the six-week follow-up and fewer intrusive symptoms at both time points. Nonsigificant differences that were found in diagnostic incidence of ASD may Nave been due to small number of patients meeting ASD criteria. Patients with partial memories were found to be similar to nonamnesics in hormone profile and symptomatology. These results suggest that amnesics may be less likely to meet diagnostic criteria for posttraumatic stress syndromes due to lesser incidence of intrusive symptoms, and that the lack of re-experiencing phenomenon may contribute to differences in subsequent neuroendocrine functioning.