Head injury as a PTSD predictor among Oklahoma City bombing survivors.

BACKGROUND: The aim of the Oklahoma City (OKC) bombing retrospective review was to investigate the relationship between physical injury, environmental contributors, and psychiatric disorders such as posttraumatic stress disorder (PTSD) in an event-based, matched design study focused on injury. METHODS: The 182 selected participants were a random subset of the 1,092 direct survivors from the OKC bombing. Only 124 of these 182 cases had a full complement of medical/clinical data in the OKC database. These 124 cases were assessed to explore relationships among PTSD diagnoses, levels of blast exposure, and physical injuries. Associations among variables were statistically tested using contingency analysis and logistic regression. RESULTS: Comparison of the PTSD cases to symptoms/diagnoses reported in the medical records reveals a statistically significant association between PTSD and head/brain injuries associated with head acceleration. PTSD was not highly correlated with other injuries. Although blast pressure and impulse were highly correlated with head injuries, the correlation with PTSD was not statistically significant. Thus, a correlation between blast pressure and PTSD may exist, but higher fidelity pressure calculations are required to elucidate this potential relationship. CONCLUSIONS: This study provides clear evidence that head injury is associated with subsequent PTSD, giving caregivers' information on what physical injuries may suggest the development of psychologic disorders to aid them in developing a profile for the identification of future survivors of terrorist attacks and Warfighters with brain injuries and potential PTSD.

A neuropsychiatric perspective on traumatic brain injury.

Traumatic brain injury (TBI) due to closed mechanisms causes strain injuries to axons that increase in number and severity as injury severity increases. Axons that project up from the brain stem are vulnerable, even in milder concussive injuries, and include axons that participate in key monoaminergic pathways. Although called diffuse axonal injury, the supra-tentorial injury component typically shows an anterior preponderance in humans. As the injury forces increase, cerebral contusions may be superimposed on the axonal strain injuries, and these contusions show an anterior preponderance as well. The chronic neuropsychiatric manifestations of TBI reflect this injury distribution. In the cognitive sphere, these manifestations almost always include power function disturbances marked by difficulties with cognitive processing speed, multitasking, and cognitive endurance. These disturbances may then be followed by disturbances in executive function and self-awareness as injury severity increases. In the behavioral sphere, mood disturbances and disorders of behavioral control and regulation are particularly common.

The neurocognitive basis of compromised autonomy after traumatic brain injury: clinical and ethical considerations.

It is widely accepted, based on the principle of respect for autonomy, that there are ethical constraints on the range of tactics that persons may use to influence the decisions and behaviors of others. However, accurate ascriptions of autonomy to either persons or acts may vary considerably, depending on properties of the person, the situation, or both. Traumatic brain injury affects cognitive domains that are critical for the effective exercise of autonomy, and so offers a context for further examination of this variability. Analysis of the neuropathology of traumatic brain injury and its neurocognitive consequences provides a foundation for understanding cases in which autonomy is compromised even though legal competency may be preserved. Respecting autonomy in these cases is not always straightforward; it may entail both special ethical obligations and consideration of tactics that would not be morally permissible under other circumstances.