Is There a Subtle Thyroid Hormone Secretion Abnormality in Euthyroid Non-Functional Adrenal Incidentalomas ?

Program: Abstracts - Orals, Featured Poster Presentations, and Posters
Session: MON 1-36-Adrenal Incidentaloma & Carcinoma
Clinical
Monday, June 17, 2013: 1:45 PM-3:45 PM
Expo Halls ABC (Moscone Center)

Poster Board MON-34
Melia Karakose1, Basak Karbek1, Oya Topaloglu1, Muyesser Sayki Arslan1, Mustafa Sahin2, Gonul Erden1, Taner Demirci1, Mustafa Caliskan1 and Tuncay Delibasi*1
1Diskapi Yildirim Beyazit Training and Research Hospital, Ankara, Turkey, 2Ankara University Faculty of Medicine, Ankara, Turkey
Introduction:

The widespread use of abdominal imaging methods led to an increase in the incidence of  incidental adrenal mass. Patients with incidental nonfunctioning adrenal adenoma  have increased risk of obesity, impaired glucose tolerance and dyslipidemia. We aimed to investigate the relationship between thyroid function, serum lipids and insulin resistance  in a sample of euthyroid subjects in the nonfunctioning adrenal incidentalomas.

Materials and Methods:

Forty  patients with adrenal incidentaloma (AI) who had diagnosed between October 2011 and  August 2012  at the Department of Endocrinology and Metabolic Diseases, Diskapi Yıldırım Beyazıt Training and Research Hospital were included in the study.  The control group included 61 age-matched  healthy volunteers. Hormonal evaluation included 8.00 a.m. cortisol, adrenocorticotropic hormone (ACTH), dehidroepiandrosteronsülfat (DHEAS), plasma renin activity, serum aldosterone. Urinary metanephrine and normetanephrine were measured. Overnigt 1 mg dexamethasone suppression test was performed. Serum free triiodothyronine (fT3), free thyroxine (fT4), thyroid stimulating hormone (TSH), anti-thyroperoxidase antibody (anti-TPO Ab) and anti-thyroglobulin antibody (anti-Tg Ab), lipid profile, HsCRP, fasting insulin levels were measured and insulin resistance calculated by  HOMA-IR.

Results:

None of the patients showed specific signs and symptoms of hormone excess. There weren’t any significant differences in age, gender, body mass index between the patients and controls group. The TSH and fT3 levels in the patients and controls group did not differ significantly (p> 0.05). The serum fT4 levels in the patients group were significantly higher than in the control group (p=0.013). The Hs-CRP, HDL cholesterol levels and HOMA-IR in the AI patients were significantly higher than the control group (p = 0.034, p=0.008, p = 0.002,  respectively). We found a significant positive correlation between fT4 and HOMA-IR, HDL cholesterol(r=0.382, p=0.015; r=0.366, p=0.02 respectively).  On the contrary there were not a relation between cortisol levels and fasting glucose levels, HOMA-IR, lipid parameters.

Conclusions:

Patients with adrenal incidentaloma might have  several  metabolic disturbances. We demonstrated that fT4 level has a positive correlation with HOMA-IR and HDL cholesterol levels in nonfunctioning adrenal incidentaloma patients who were euthyroid. Subtle abnormalities in thyroid hormone secretion may be found in adrenal incidentalomas. Further prospective studies should be performed to determine the clinical significance of these findings in adrenal incidentaloma patients.

Nothing to Disclose: MK, BK, OT, MS, MS, GE, TD, MC, TD

*Please take note of The Endocrine Society's News Embargo Policy at http://www.endo-society.org/endo2013/media.cfm