Psychological and biological correlates of fatigue after mild-to-moderate traumatic brain injury.

Relationships between chronic perceived stress, cortisol response (area under the curve) and posttraumatic brain injury fatigue were examined with persons from outpatient settings. Seventy-five injured persons with traumatic brain injury and their relatives/significant others participated in this cross-sectional study. Using interviews and self-reported data from the Neurofunctional Behavioral Inventory, the Perceived Stress Scale, the Profile of Mood States-Fatigue subscale, the McGill Pain Scale, as well as self-collection of salivary cortisol over a 12-hour period (N = 50), we found that perceived chronic stress explained 40% of the variance in fatigue until depressive symptoms and pain were in the model. Hypocortisolemia was evident. Somatic symptom frequency and perceived chronic stress represented 50% of the variability in post-TBI fatigue. Fatigue and stress management interventions, as suggested in the Centers for Disease Control Acute Concussion guidelines, may be beneficial in reducing this common symptom.