The stress axis gone awry: A possible neuroendocrine explanation for increased risk of completed suicide

While the dexamethasone suppression test (DST) has not proven useful as a diagnostic test for "true" depression, it shows increasing promise as a potential indicator of psychiatric patients at increased risk for suicide. An indicator of the activity level of the hypothalamic-pituitary-adrenal (HPA) axis, the DST is an endocrine test that has caught the interest of psychiatric researchers throughout the last century because of the role of the HPA axis in managing an organism's homeostasis and stress response. This article will present a brief literature review of the role of the DST in psychiatry. It will propose a hypothesis, supported by data from two recent small studies, that suggests that chronic overdrive in the HPA axis, as manifested in a nonsuppressing DST, may result in an increased likelihood of suicide when the individual is acutely stressed.