CLINICS 2010;65(1):9-13 CLINICAL SCIENCE SCREENING FOR CUSHING’S SYNDROME IN OBESE PATIENTS Ozay Tiryakioglu, Serdal Ugurlu, Serap Yalin, Sibel Yirmibescik, Erkan Caglar, Demet Ozgil Yetkin, Pinar Kadioglu doi: 10.1590/S1807-59322010000100003 Tiryakioglu O, Ugurlu S, Yalin S, Yirmibescik S, Caglar E, Yetkin DO et al. Screening for Cushing’s Syndrome in obese patients. Clinics. 2010;65(1):9-13. OBJECTIVES: The aim of this study was to examine the frequency of Cushing’s syndrome (CS) in obese patients devoid of specific clinical symptoms of Cushing’s syndrome. METHODS: A total of 150 obese patients (129 female, 21 male; mean age 44.41 ± 13.34 yr; mean BMI 35.76 ± 7.13) were in- cluded in the study. As a first screening step, we measured 24-h urinary free cortisol (UFC). An overnight 1-mg dexamethasone suppression test was also performed on all patients. Urinary free cortisol levels above 100 µg/24 h were considered to be abnormal. Suppression of serum cortisol <1.8 µg/dL after administration of 1 mg dexamethasone was the cut-off point for normal suppression. The suppression of the serum cortisol levels failed in all of the patients. RESULTS: Measured laboratory values were as follows: ACTH, median level 28 pg/ml, interquartile range (IQR) 14-59 pg/ml; fasting glucose, 100 (91-113) mg/dL; insulin, 15.7 (7.57-24.45) mU/ml; fT4, 1.17 (1.05-1.4) ng/dL; TSH, 1.70 (0.91-2.90) mIU/L; total cholesterol, 209 (170.5-250) mg/dL; LDL-c, 136 (97.7-163) mg/dL; HDL-c, 44 (37.25-50.75) mg/dL; VLDL-c, 24 (17-36) mg/dL; triglycerides, 120.5 (86-165) mg/dL. The median UFC level of the patients was 30 µg/24 h (IQR 16-103). High levels of UFC (>100 µg/24 h) were recorded in 37 patients (24%). Cushing’s syndrome was diagnosed in 14 of the 150 patients (9.33%). Etiologic reasons for Cushing’s syndrome were pituitary microadenoma (9 patients), adrenocortical adenoma (3 patients), and adrenocortical carcinoma (1 patient). CONCLUSION: A significant proportion (9.33%) of patients with simple obesity were found to have Cushing’s syndrome. These findings argue that obese patients should be routinely screened for Cushing’s syndrome. KEYWORDS: Cushing’s syndrome. Obesity. Screening. Cortisol. Adrenocorticorticotropic hormone. INTRODUCTION Obesity is the most common metabolic problem in industrialized countries. In the USA, 32% of adults are classified as overweight, and 22.5% of these individuals are obese.1 Both overweight and obese subjects are at an increased risk for cardiovascular diseases,2 some types of cancer,3 diabetes4, and even premature death.5 Obesity is often accompanied by other chronic disorders including Division of Endocrinology and Metabolism, Department of Internal Medicine, Cerrahpasa Medical Faculty - Sivas, Turkey. Email: kadioglup@yahoo.com Tel: 90 216 4623114 Received for publication on September 11, 2009 Accepted for publication on October 08, 2009 hypertension, osteoarthritis, bile stones, and dyslipidemia.6-12 In addition to these physical disorders, obesity is commonly associated with psychological and psycho-social problems.10 Obesity can coexist with diverse physical disorders, and physicians should first focus on the differential diagnosis of possible underlying disorders before initiating any management procedure. Obesity is a prominent feature of endocrine diseases including hypothyroidism, insulin-excess syndromes, polycystic ovary syndrome (PCOS), hypogonadism, hypothalamic disease/injury, growth hormone deficiency, leptin deficiency or leptin receptor defects, pseudohypoparathyroidism, and Cushing’s syndrome (CS).11,12 Diagnosis of CS is primarily based on the signs and 9