Many studies suggest that there is a hyperactivity of the hypothalamic-pituitary-adrenal (HPA) axis related to obesity with accumulation of fat in the abdominal region. Some studies demonstrate that after the injection of corticotrophin-releasing hormone (CRH) or corticotrophin (ACTH) and according to the results of stress tests, the levels of cortisol are increased when compared to patients with peripheral fat deposition. Moreover, some studies show that in depressed patients, where the hyperactivity of HPA is known and represents an important endocrinological change, the adrenal volume is increased. To investigate if the amount of visceral fat is related in some way to adrenal gland volume, a group of 52 women with different corpulence indexes was studied. Anthropometries measures, such as weight, body mass index (BMI), waist circumference and waist-to-hip ratio (WHR) were checked. The areas of visceral and subcutaneous fat, as well as adrenal gland volumes, were checked by abdominal computed tomography. There was an extremely relevant correlation between the measurements of central fat deposition (WHR and waist circumference) and the amount of visceral fat (VF), although no correlation was found between the WHR and the subcutaneous fat. The added adrenals volumes showed a positive correlation to the WHR (r = 0.272; p = 0.02) and also to the VF (r = 0.228; p = 0.05). No correlation with the subcutaneous fat, BMI, and weight were found. The added adrenals volumes were increased when VF > or = 120 cm² as compared with patients with VF < 120 cm² (p = 0.05). Thus, this study suggests that the amount of VF seem to be related to the HPA hyperactivity, anatomically expressed in this study by the adrenal volume, the target gland of this axis.
Obesity; Adrenal glands; Hypothalamichypophyseal-adrenal axis; Cortisol; Computerized tomography
