Endocrine Abstracts

Introduction: Because of a long-term glucocorticoid replacement over many years, patients with Addison disease may have an increased occurrence of osteoporosis. Furthermore, the prevalence of osteoporosis in patients with Addison disease may also be increased because of premature menopause associated autoimmune endocrinopathies and hypovitaminosis D.The objective of this study is to assess the incidence and risk factors for osteoporosis among patients with Addison disease.

Patients and methods: A cross-sectional study including 50 patients with Addison disease who had been receiving glucocorticoid replacement therapy for at least 5 years.Bone mineral density of the lumbar spine and both femoral necks was measured on osteodensitometry. The incidence of osteoporosis and its potential predictive factors were analyzed.

Results: Our study included 40 females and 10 males with a mean age of 49,5±13,9 years (18-78 years). Average age at diagnosis was 35,5±14,6 years (0-70 years). All patients were on hydrocortisone replacement, taking mean daily dose of 27,4±6,7 mg (15-42,1 mg) corresponding to 0,388±0,128 mg/kg.Mean cumulative hydrocortisone dose was 374,636±283,821 mg (60 – 1184, 94 mg). No patient received antiresorptive therapy (oestrogen substitution therapy, bisphosphonates).Low bone mineral density was observed in 24 (48%) patients, 12 (24%) of whom had osteoporosis. No osteoporotic fracture was observed.Patients who developed osteoporosis were significantly older than those with normal bone mineral density were (P=0,018). Menopause was a significant predictor of incident osteoporosis (P=0,006). Furthermore, osteoporosis was significantly more prevalent among females (P=0,046).No statistically significant association was found between osteoporosis and Addison disease duration neither the body mass index.Daily and cumulative hydrocortisone dose were higher in patients with osteoporosis than those with normal osteodensitometry (26,5±8,3 mg/day vs 25,6±6,3 mg/day; 462,2±373,2 mg vs 344,6±245,5 mg) but without statistical significance.

Conclusion: Identification of predictive factors of osteoporosis in patients with Addison disease is useful in the management of long –term glucocorticoid therapy‘s bone impact. Then, further studies are needed to better analyze these factors and control bone mineral density during the course of Addison disease.