 We propose to use a case control design to test the main hypothesis that as compared to healthy control subjects matched for sex, age, adiposity and raceethnicity, patients with adrenal insufficiency, whether primary or secondary, have disturbances of the circadian system that are associated with high day to day variability of sleep time as well as elevated markers of cardio-metabolic risk, including abnormal oral glucose tolerance and reduced nocturnal blood pressure dipping. 