OBJECTIVE: Reevaluation of the validity of the 1-mg overnight dexamethasone suppression test (ODST) as a screening test for Cushing's syndrome in obese patients. RESEARCH METHODS AND PROCEDURES: Eighty-six obese patients (body mass index, 30 to 53 kg/m(2)) that were referred to a general endocrine outpatient clinic for evaluation of simple obesity, diabetes mellitus, hypertension, polycystic ovary disease, or pituitary tumor. One milligram dexamethasone was administered orally at 11:00 PM, and serum cortisol levels were measured the following morning between 8:00 AM and 9:00 AM. Suppression of serum cortisol to <80 nM (3 micro g/dL) was chosen as the cut-off point for normal suppression. Patients with serum cortisol levels > or =80 nM were evaluated for Cushing's syndrome. RESULTS: Suppression of morning cortisol levels to <80 nM occurred in 79 of the 86 obese patients. Seven patients had serum cortisol levels higher than 80 nM; five were eventually diagnosed with Cushing's syndrome and two were considered false positive results in view of normal 24-hour free urinary cortisol and normal suppression on a low dose dexamethasone suppression test (0.5 mg of dexamethasone every 6 hours for 2 days). We found a false positive rate of 2.3% for the ODST using a cut-off serum cortisol of 80 nM. DISCUSSION: The ODST is a valid screening test for Cushing's syndrome in the obese population. The false positive rate was 2.3%, even when using a strict cut-off serum cortisol of 80 nM. Abnormal cortisol suppression in obese patients should be investigated and not be considered false positive results.
OBJECTIVE: Reevaluation of the validity of the 1-mg overnight dexamethasone suppression test (ODST) as a screening test for Cushing's syndrome in obesepatients. RESEARCH METHODS AND PROCEDURES: Eighty-six obesepatients (body mass index, 30 to 53 kg/m(2)) that were referred to a general endocrine outpatient clinic for evaluation of simple obesity, diabetes mellitus, hypertension, polycystic ovary disease, or pituitary tumor. One milligram dexamethasone was administered orally at 11:00 PM, and serum cortisol levels were measured the following morning between 8:00 AM and 9:00 AM. Suppression of serum cortisol to <80 nM (3 micro g/dL) was chosen as the cut-off point for normal suppression. Patients with serum cortisol levels > or =80 nM were evaluated for Cushing's syndrome. RESULTS: Suppression of morning cortisol levels to <80 nM occurred in 79 of the 86 obesepatients. Seven patients had serum cortisol levels higher than 80 nM; five were eventually diagnosed with Cushing's syndrome and two were considered false positive results in view of normal 24-hour free urinary cortisol and normal suppression on a low dose dexamethasone suppression test (0.5 mg of dexamethasone every 6 hours for 2 days). We found a false positive rate of 2.3% for the ODST using a cut-off serum cortisol of 80 nM. DISCUSSION: The ODST is a valid screening test for Cushing's syndrome in the obese population. The false positive rate was 2.3%, even when using a strict cut-off serum cortisol of 80 nM. Abnormal cortisol suppression in obesepatients should be investigated and not be considered false positive results.
Authors: Lynnette K Nieman; Beverly M K Biller; James W Findling; John Newell-Price; Martin O Savage; Paul M Stewart; Victor M Montori Journal: J Clin Endocrinol Metab Date: 2008-03-11 Impact factor: 5.958
Authors: Maurizio De Luca; Luigi Angrisani; Jacques Himpens; Luca Busetto; Nicola Scopinaro; Rudolf Weiner; Alberto Sartori; Christine Stier; Muffazal Lakdawala; Aparna G Bhasker; Henry Buchwald; John Dixon; Sonja Chiappetta; Hans-Christian Kolberg; Gema Frühbeck; David B Sarwer; Michel Suter; Emanuele Soricelli; Mattias Blüher; Ramon Vilallonga; Arya Sharma; Scott Shikora Journal: Obes Surg Date: 2016-08 Impact factor: 4.129
Authors: Bradley R Javorsky; Ty B Carroll; Nicholas A Tritos; Roberto Salvatori; Anthony P Heaney; Maria Fleseriu; Beverly M K Biller; James W Findling Journal: Obes Surg Date: 2015-12 Impact factor: 4.129