Hippocampal Volume Varies With Acute Posttraumatic Stress Symptoms Following Medical Trauma

The hippocampus and amygdala play an important role in the pathophysiology of posttraumatic stress disorder (PTSD). In fact, chronic PTSD has been consistently linked to reductions in hippocampal and amygdala volume. However, the acute impact posttraumatic stress has on the volume of these brain regions has received limited attention. Determining the acute impact posttraumatic stress has on brain volume may improve our understanding of the development of PTSD. Therefore, the present study recruited participants acutely (i.e., similar to 1-month posttrauma) following trauma exposure and examined the relationship between brain volume (assessed at similar to 1-month posttrauma) and posttraumatic stress symptoms (assessed at similar to 1 and >3-months posttrauma) to determine whether brain volume was associated with acute posttraumatic stress symptom expression. Twenty-one trauma-exposed (TE) patients and 19 nontrauma-exposed (NTE) controls were recruited for the present study. Brain volume was assessed by structural magnetic resonance imaging completed during the similar to 1-month assessment. Left hippocampal volumes were smaller in TE than NTE participants. Among TE participants, bilateral hippocampal volumes decreased as the number of days posttrauma increased. Further, bilateral hippocampal volumes varied negatively with the severity of posttraumatic stress symptoms at similar to 1-month posttrauma. The present findings suggest that there is a progressive decrease in hippocampal volume acutely (e.g., within approximately 1 month) following trauma exposure, and demonstrates that acutely assessed hippocampal volumes vary with posttraumatic stress symptom expression.

Automated summary

The study revealed that there is a progressive decrease in hippocampal volume acutely (e.g., within approximately 1 month) following trauma exposure, and demonstrated that acutely assessed hippocampal volumes vary with posttraumatic stress symptom expression.