Prevalence, risk factors and management of bone complications in Cushing`s syndrome across Europe. Data from the European Registry on Cushing’s syndrome (ERCUSYN)

Objective: The aim of the study was to investigate bone comorbidities and their management in patients included in the European Register on Cushing`s syndrome (ERCUSYN). Design: A retrospective multicentric cohort study and on-line survey. Methods: We analyzed the prevalence of osteoporosis (OP) and fractures among 1682 patients with Cushing`s syndrome (CS), at initial evaluation and during follow-up. All the ERCUSYN partners received a survey addressing bone disease management in CS. Results: Seven hundred and sixty-six patients (45%) had DXA examination at baseline, of whom 157 (21%) presented OP at spine and 103 (13%) at hip. Risk factors for OP were older age (p=0.038) and lower BMI (p=0.022). An X-ray was performed in 492 (29%) patients and fracture was detected in 87 (18%). Risk factors for fractures at baseline were male sex (p<0.001), muscle weakness (p=0.026) and bone mineral density (BMD) at hip indicating OP (p=0.026). During follow-up, spine BMD deterioration was more common in older patients (p=0.005) and in those with diabetes mellitus (p=0.024), while worsening of hip BMD was more frequent in patients with hypopituitarism (p=0.021), diabetes mellitus (p=0.034), on levothyroxine substitution (p=0.008) and those less often treated with anti-osteoporotic agents (p=0.022). The survey evidenced significant heterogeneity in terms of timing of bone evaluation and treatment initiation. Conclusions: A significant number of patients with CS experienced OP and fractures. Clinical factors may help to select patients at the highest risk. There are currently no standards of care for the management of bone complications in CS across Europe.