Endocrine Abstracts

Introduction: Subclinical hypercortisolism (SH), affecting about 30% of patients with unilateral adrenal incidentaloma (UAI), has been associated to hypertension (HT), type 2 diabetes mellitus (T2DM), dyslipidemia (DL), osteoporosis and vertebral fractures (FX). The prevalence of SH in patients with bilateral adrenal incidentaloma (BAI) seems to be even higher. Data on metabolic and bone complications in these patients are lacking.

Methods/design: We enrolled 175 patients with UAI (116 F; 59 M) and 35 patients with BAI (24 F; 11 M). In all patients we evaluated: BMI, bone mineral density (BMD) by DEXA at spine, total and femoral neck (expressed as Z-values: Z-LS, Z-FT, Z-FN respectively), the presence of HT, T2DM, DL and FX (diagnosed using a semi-quantitative visual assessment). We diagnosed SH in the presence of at least two out of: urinary free cortisol levels (UFC) >70 μg/24 h, serum cortisol levels after 1 mg-dexamethasone test (1 mg-DST) >3.0 μg/dl or ACTH levels <10 pg/ml.

Results: Age, BMI, diameter of adenoma, UFC, 1 mg-DST, ACTH e Z-LS were comparable between the two groups. Total and femoral BMD were significantly lower in patients with BAI when compared to those of UAI (−0.28±0.99 vs Z-FT: 0.25±1.1, P=0.008; Z-FN: −0.40±0.88 vs 0.09±1.1, P=0.01). The prevalence of SH, HT, T2DM, DL was comparable between groups, while the prevalence of FX was higher in BAI than in UAI (51% vs 28%, P=0.007). Logistic regression analysis showed that the presence of FX was independently associated to the presence of BAI (OR 2.7, 95% CI 1.2–6.0; P=0.02), age (OR1.07, 95% CI 1.0–1.1; P=0.001), and Z-LS (OR 0.7, 95% CI 0.6–0.9; P=0.01) regardless for the presence of SH (OR 2.0, 95% CI 0.9–4.1; P=0.06).

Conclusion: Patients with BAI show a lower BMD and a higher prevalence of FX than patients with UAI, independently of SH.

Declaration of interest: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.

Funding: This research did not receive any specific grant from any funding agency in the public, commercial or not-for-profit sector.