Lower stress-reactive cortisol in female veterans associated with military status but not PTSD

Female veterans are a growing yet understudied population. Currently, 14.6% of all troops deployed to Afghanistan and Iraq are female. Military service is associated with an increased risk for trauma exposure and subsequent development of posttraumatic stress disorder (PTSD). Dysregulation of the hypothalamic-pituitary-adrenal axis is frequently associated with PTSD. Few studies have examined females diagnosed with PTSD and only one study, to our knowledge, has examined HPA-axis dysregulation in female veterans. This study examined salivary cortisol in 52 female veterans and civilians both with and without PTSD. We collected saliva samples at bedtime and awakening, as well as in response to the Trier social stress test (TSST). We found that female veterans had blunted cortisol concentrations at all time points during the TSST compared to female civilians, regardless of PTSD status. Even though all groups showed the expected diurnal decline in cortisol, the difference between awakening and bedtime samples were significant only in civilians without PTSD. The results of our study suggest that stressors specific to the military may lead to lower than normal cortisol, which may not be associated with the expressions of PTSD.