“…5,7,8 The present study focuses on the HPA-axis, which plays a central role in the neuroendocrine response to stress with cortisol being it's main effector constituent, since both IBS and depression have been reported to exhibit HPAaxis dysregulation and that stress-dysregulation has been suggested as one important etiologic factor in both conditions. [9][10][11][12][13][14][15][16][17][18] While stress has traditionally been associated with increased cortisol levels and HPA-axis hyperactivity, there is a growing body of literature describing lowered cortisol levels and hypoactivity of the HPA-axis in a number of stress related disorders [19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35] ; eg, posttraumatic stress disorder (PTSD), 30,31 chronic fatigue syndrome, [22][23][24] burnout, 25,26 as well as in fibromyalgia and chronic somatic pain conditions of unknown or uncertain etiology. 28,29,[32][33][34] Dysfunction of the HPA-axis, including hypoactivity, has also been reported in IBS.…”