Endocrine Abstracts

Introduction: Even at physiological doses, glucocorticoid replacement therapy may lead to deleterious outcomes on bone mineral density (BMD).The aim of our study was to investigate the BMD in Tunisian patients with Addison disease and to identify the risk factors associated with its decline.

Patients and methods: The study included 50 patients diagnosed with primary adrenal disease (Addison disease). BMD was assessed by the dual -energy -X-ray absopitometry. Predictive factors of reduced BMD were analyzed.

Results: The mean age of patients was 49,5±13,9 years and 40 patients were female;42,5% menopausal. Disease duration was 13,9±8,7 years.). All patients were on hydrocortisone replacement, taking daily 27,4±6,7 mg (15-42,1 mg) corresponding to 0,388±0,128 mg/kg. Hypovitaminosis D was observed in 66% of patients. Twenty percent of patients had a higher than normal level of parathyroid hormone (PTH).The BMD was significantly reduced in 48% of patients. Three patients presenting congenital adrenal hyperplasia had normal BMD.A significant higher incidence of reduced BMD was observed among menopausal women (P=0,049). Moreover, a higher mean PTH level was found in patients with decreased BMD but without statistically significant difference (56±21,8 pg/ml vs 48,1±25,4 pg/ml;P=0,1).A lower mean vitamin D level was also found among those patients (19±10,2 ng/ml vs 25,2±16 ng/ml).Cumulative hydrocortisone dose was higher among patients with reduced BMD compared to those with normal BMD, without statistical significance (408,9±324 mg vs 338,9±236 mg;P=0,7).No significant correlation was identified between decreased BMD and duration of glucocorticoid substitution.

Conclusion: Bone loss is frequent in patients with Addison disease taking long-term glucocorticoid therapy and related to many factors affecting bone remodeling such as hydrocortisone dose and vitamin D deficiency. It seems imperative to ensure long-term follow-up of changes in BMD in patients with Addison disease.