Male: higher UFC and ACTH values, lower ACTH response to DDAVP stimulation. Pituitary tumor less easily visualized by pituitary MRI. More frequent or more severe complications, in particular hypokalemia, hypercoagulable state, and osteoporosis at lumbar spine, with consequent higher risk of vertebral fractures. Male sex was an independent risk factor for dyslipidemia, severity of hypertension, lumbar osteoporosis and fractures.Both sexes: No differences in age at diagnosis, disease duration and BMI. The prevalence of hypogonadism did not significantly differ. This evidence concerns the gene POMC and thrombophilia.