Endocrine Abstracts

Introduction: Osteoporosis is a well-recognized complication of Cushing’s disease (CD). It results from a combination of systemic and local effects that glucocorticoids have on bone and mineral metabolism. The prevalence of osteoporosis due to excess endogenous cortisol has been reported at 50-59%, trabecular bone is more severely affected in CS than cortical bone.

Goal of the study: : To assess the prevalence of bone involvement in patients with Cushing’s disease.

Patients and methods: This is a retrospective study of a sample of 69 patients with ACTH-dependent Cushing’s disease, collected between (January 2000–December 2022), followed in the endocrinology department of Bologhine. We excluded patients with exogenous Cushing’s syndrome and a history of metabolic bone disease and systemic disease such as rheumatoid arthritis, bronchial asthma, or a history of taking bone-affecting antiepileptic drugs. BMD was measured by dual-energy X-ray absorptiometry (DXA) at the level of the lumbar spine (L1–L4, AP) and femur, recorded in terms of absolute mineral content in g/cm ² and Z -score, T-score at both sites.

Results: On a sample of 69 patients: The average age is 43 years, with a sex ratio of 4/1 (4 F, 1 M). Only 43 patients among them (69) benefited from a BMD. Osteoporosis is found in 48.8% of patients, osteopenia in 39.5% and only 11.6% of the cohort have normal BMD. Severe osteoporosis, ie osteoporosis associated with a bone fracture, was present in 3 cases with case of vertebral compression. The Z-score values were significantly lower at the vertebral level with an average of (-1.9) than at the femoral level with an average of (-1.1) (P= 0.001). The difference in BMD was not significant between patients without cycle disorders and oligo-/ amenorrhoeic patients with Cushing’s disease. (P-value: 0.43) We found a negative correlation with morning plasma cortisol and BMD at the vertebral level (r ² = 0.22, P= 3.55X 10 ^-15 ) and at the hip (r ² = 0.13, P= 5.25X10 ^-15 ) although that is not statistically significant.

Conclusion: Our study clearly showed that vertebral BMD in patients with Cushing’s disease is more affected than femoral BMD. Osteoporosis must therefore be systematically sought and treated in order to avoid these complications which can compromise the prognosis.