Post-traumatic stress disorder: An overview and its relationship to closed head injuries

Abstract

While exposure to traumatic psychological and physical trauma can produce post-traumatic stress disorder (PTSD), multiple factors determine whether a person will develop PTSD following trauma exposure. Such factors include, but are not limited to, female gender, social disadvantage, childhood adversity, genetic predisposition, and substance abuse. PTSD has a high rate of comorbidity with psychiatric, substance abuse, and somatization disorders. Persons with PTSD experience profound and persistent alterations in their physiological reactivity to internal and external stimuli which prevents them from utilizing their emotions to process incoming information. These patients have chronically high levels of sympathetic nervous system activity and low levels of glucocorticoids to cope with stress and modulate their catecholamine levels. Neuropsychological assessment of patients with PTSD depends to a large degree on the sensitivity of the measures which are utilized and a pre-existing history of learning disabilities, head trauma, and/or neurological disorders. While closed head injuries (CHI) are unlikely to produce PTSD symptoms, persons with CHI are likely to develop PTSD symptoms if they are exposed to trauma prior to the onset of retrograde amnesia or after the resolution of post-traumatic amnesia. If the traumatic event occurs while the patient with CHI is amnestic or unconscious, they are unlikely to develop PTSD symptoms. The liberal criteria used to diagnose mild CHI is likely to result in patients with acute stress disorders being misdiagnosed with CHI as a result of their dissociative symptoms which reduce their awareness and encoding of the traumatic event.