Effects of sex steroids on bone in women with subclinical or overt endogenous hypercortisolism

OBJECTIVE: Glucocorticoid-induced osteoporosis is the most frequent cause of secondary osteoporosis. Nevertheless, limited data are available on bone status in patients with endogenous cortisol excess. This study is aimed at investigating the role of sex steroids and severity of hypercortisolism on bone mineral density (BMD) and prevalence of vertebral fractures in female patients. DESIGN: Cross-sectional, case-control study. Patients: Seventy-one consecutive women were enrolled: 36 with overt hypercortisolism (26 with ACTH-secreting pituitary adenoma and 10 with cortisol-secreting adrenal tumor) and 35 with subclinical hypercortisolism due to adrenal incidentalomas. They were compared with 71 matched controls. METHODS: At diagnosis, we measured serum cortisol, FSH, LH, estradiol, testosterone, androstenedione and DHEAS, and urinary cortisol excretion. BMD was determined by dual energy X-ray absorptiometry at the lumbar spine and femoral neck. Vertebral fractures were investigated by a semiquantitative scoring method. RESULTS: Between women with overt and subclinical hypercortisolism BMD values and prevalence of any vertebral (69 vs 57%, P = 0.56), clinical (28 vs 11.4%, P = 0.22), and multiple vertebral fractures (36 vs 31%, P = 0.92) did not differ. Among patients with subclinical hypercortisolism, amenorrhoic women had a lower BMD (P = 0.035) and more frequent vertebral fractures (80 vs 40%; P = 0.043) when compared with the eumenorrhoic ones. Among women with overt hypercortisolism, there was no difference in lumbar BMD (P = 0.37) and prevalence of fractures (81 vs 60%; P = 0.26) between those amenorrhoic and eumenorrhoic. By logistic regression analysis, lumbar spine BMD values and cortisol-to-DHEAS ratio were the best predictors of vertebral fractures (P < 0.01). CONCLUSIONS: Vertebral fractures are very common in women with endogenous cortisol excess, regardless of its severity. The deleterious effects of hypercortisolism on the spine may be partly counterbalanced by DHEAS increase at any degree of cortisol excess, and by preserved menstrual cycles in women with subclinical but not in those with overt hypercortisolism.