released from the pituitary and may vary under rest and challenge conditions,25-27 we also assessed adrenal sensitivity as a ratio of cortisol to corticotropin. Furthermore, previous research on conditions with known HPA axis disturbances (eg, rheumatoid arthritis and posttraumatic stress disorder) have found the cortisol to corticotropin ratio as a measure of adrenal sensitivity to be an important marker of clinical symptoms and outcome.28,29 Cortisol and corticotropin are measured in mass concentrations and a ratio of cortisol to corticotropin was computed as in previous studies.27,28
