Plasma beta-endorphin levels in post-traumatic stress disorder: a preliminary report on response to exercise-induced stress

Post-traumatic stress disorder (PTSD) may be associated with changes in endogenous opioid peptide function. To test this hypothesis, 10 male Vietnam combat veterans with PTSD and 8 age-matched male controls underwent a standard grade-incremented exercise treadmill stress test. Plasma beta-endorphin measurements were obtained at rest and following maximal exercise. Resting plasma beta-endorphin levels were comparable between groups. Post-exercise plasma beta-endorphin levels were significantly higher than resting levels in the PTSD patients only (P less than 0.05). These pilot data suggest a differential alteration in plasma beta-endorphin response to exercise in PTSD.