Eugonadal male patients with adrenal incidentalomas and subclinical hypercortisolism have increased rate of vertebral fractures

Subclinical hypercortisolism (SH) is suggested to exert a deleterious effect on bone. This effect and the role of gonadal status in male subjects are not fully elucidated. We evaluated bone mineral density (BMD) and prevalence of vertebral fractures in eugonadal male subjects with adrenal incidentalomas (AI) and without SH. This 12-month observational multicentre study was performed between January and December 2006 on inpatient basis in three referral Italian centres. Eighty-eight consecutive eugonadal male patients with AI and 90 matched control subjects were studied. All subjects underwent the determination of BMD by dual-energy X-ray absorptiometry at lumbar spine (LS) and femoral neck (FN), and spinal radiograph. In AI patients SH was diagnosed in the presence of two of the following: urinary free cortisol > 193.1 nmol/l, cortisol after 1 mg dexamethasone suppression test > 82.8 nmol/l, ACTH levels < 2.2 pmol/l. As compared to patients without SH (SH-, n = 66) and controls, patients with SH (SH+, n = 22) had lower BMD at LS (Z-score: SH+, -1.04 +/- 1.84; SH-, 0.19 +/- 1.34, Controls 0.20 +/- 1.28, P = 0.001 and FN (Z-score: SH+, -0.63 +/- 1.01; SH-, 0.01 +/- 1.01, Controls 0.26 +/- 1.06, P = 0.002) and higher prevalence of fractures (SH+, 72.7%; SH-, 21.2%, Controls 20.0%, P = 0.0001). Multivariable analyses showed that SH was associated to BMD at LS (beta = -0.378, P = 0.0001) and vertebral fractures (OR = 7.81, 95% CI 1.96-31.17, P = 0.004). In eugonadal male patients with AI, SH is associated with low BMD and high prevalence of vertebral fractures.