ABSTRACT
Activation of the hypothalamic-pituitary-adrenal axis has been linked with depressive illnesses and chronic pain as part of a stress response that produces loss of affective and cognitive flexibility, anxiety, activation of the autonomic nervous system, sleep disturbance, and diminished sexual interest. The axis has been extensively explored in functional somatic syndromes, and the output of this work has been summarized here in an attempt to detect whether these illnesses show consistent hormonal abnormalities and whether these abnormalities suggest similarities with typical or atypical presentations of psychiatric disorders. The baseline activity of the hypothalamic-pituitary axis of patients with fibromyalgia, as reflected by 24-hour urinary cortisol excretion, was examined in a well-controlled study by investigators from the University of Antwerp, Belgium, in collaboration with researchers from Vanderbilt University, Nashville, Tennessee, and University La Sapienza, Rome. The relationship between hypothalamic-pituitary-adrenal axis function and psychopathology in irritable bowel syndrome was assessed by investigators from the University La Sapienza, Rome.
