Subclinical hypercortisolism : correlation between biochemical diagnostic criteria and clinical aspects

Objective Subclinical hypercortisolism (SH) has been associated with increased prevalence of hypertension, type 2 diabetes mellitus, dyslipidaemia, central obesity, osteoporosis and vertebral fractures. We aimed to investigate the accuracy of different SH diagnostic criteria in predicting the presence of complications. Design This was a retrospective study. Patients We evaluated data from 231 patients (120 women and 111 men) affected with adrenal incidentalomas (AI). Measurements We studied the accuracy of different SH diagnostic criteria (cortisol after 1 mg overnight dexamethasone suppression test - 1mg-DST - at different cut-off such as 49·7, 82·8, 137·9 nmoll, elevated urinary free cortisol, reduced adrenal corticotroph hormone (ACTH) levels alone or various combination of these parameters) in predicting the concomitant presence of the following three complications: hypertension, type 2 diabetes and vertebral fractures. Results The criterion characterized by the presence of two of 1mg-DST >82·8 nmoll, elevated UFC and reduced ACTH struck the best balance between sensitivity and specificity, reaching a good accuracy in predicting the cluster of complications (61·9%; 77·1% and 75·8%, respectively). The presence of this cluster was associated with this criterion (OR 4·75, 95%CI 1·8-12·7, P = 0·002) regardless of gonadal status, body mass index (BMI) and age. Conclusions The SH criterion characterized by the presence of two of 1mg-DST >82·8 nmoll, elevated UFC and reduced ACTH seems the best in predicting the presence of chronic manifestations of subtle cortisol excess.