The Severity of Bone Loss: A Comparison Between Cushing’s Disease and Cushing’s Syndrome

Background: This study aimed to estimate the prevalence of osteoporosis among patients with adrenal Cushing’s syndrome (ACS) and Cushing’s disease (CD), to investigate whether there is a difference in the degree of osteoporosis between both groups; and if so, what factors may be responsible for this variation. Methods: This is a cross-sectional study in which data from 19 patients with CD and eight patients with ACS were analyzed. Osteo-porosis was assessed using the bone mineral density (BMD) of the lumbar spine using dual-energy X-ray absorptiometry (DEXA). Results: Bone loss was present in 81.5% of the patients with Cushing’s syndrome. Osteoporosis is nearly three times more common in ACS (62.5%) than in CD (26.3%). BMD at the lumbar spine was lower in patients with ACS than in patients with CD. ACS had significantly lower levels of dehydroepiandrosterone sulfate (DHEA-S) than CD. In comparison to the CD group, the serum parathyroid hormone (PTH) concentration in the ACS group was significantly higher. In the entire patient population, there was a statistically significant correlation between the DHEA-S and the lumbar BMD values. Conclusions: Patients with ACS have more severe osteoporosis than patients with CD, and the difference in DHEA-S concentrations might be important in explaining this difference. BMD examinations should be prioritized to enable rapid recognition and intervention for osteoporosis. Measurement of bone turnover markers such as PTH may aid in the early diagnosis of the consequences of hypercortisolism on the bone.