The measurement of cortisol in saliva is becoming more widely accepted as a screening test for the diagnosis of hypercortisolism. Since 1986, cortisol measurement in saliva has been continuously used in our department. In this study we compared salivary cortisol profiles from proven Cushing's disease patients with profiles from healthy subjects and obese children. The purpose was to evaluate the predictive value of the method for the diagnosis of hypercortisolism and to define cut-off levels to exclude or identify hypercortisolism. Cortisol in saliva was measured in 150 Cushing's disease patients (30 children, 120 adults, ranging from age 4-70), 100 healthy subjects (55 children, 45 adults, ranging from age 6-60), and 31 children (age 7-15) with an age-related body-mass-index above the 90th percentile. Generally, five saliva samples were taken over the day at 6:00-8:00 a.m., 11:00-12:00 a.m., 4:00-6:00 p.m., 7:00-8:00 p.m., and 10:00 p.m. The samples were measured using a radioimmuno-assay (INCSTAR Corporation, Stillwater, Minnesota, USA). For healthy subjects, morning levels of cortisol in saliva between 3-19 microg/l were found. These levels dropped to levels in between
