Bone mineral density is not significantly reduced in adult patients on low-dose glucocorticoid replacement therapy.

CONTEXT: Patients with primary adrenal insufficiency (PAI) and patients with congenital adrenal hyperplasia (CAH) receive glucocorticoid replacement therapy, which might cause osteoporosis.

OBJECTIVES: Questions addressed by this study were: 1) Is bone mineral density (BMD) reduced in PAI and CAH on lower glucocorticoid doses than previously reported? 2) Is BMD in PAI influenced by the type of glucocorticoid used? and 3) Does DHEA treatment affect BMD in PAI women?

DESIGN AND PATIENTS: We conducted a prospective, cross-sectional study including 81 PAI patients and 41 CAH patients.

MAIN OUTCOME MEASURES: BMD was measured by dual-energy x-ray absorptiometry. Serum levels of bone turnover markers, minerals, vitamins, hormones, and urinary crosslinks were measured.

RESULTS: PAI and CAH patients received average daily hydrocortisone doses of 12.0 ± 2.7 mg/m(2) (range, 4.9-19.1) and 15.5 ± 7.8 mg/m(2) (range, 5.7-33.7), respectively. BMD varied within the normal reference range (-2 to +2) in both cohorts. However, lower Z-scores for femoral neck and Ward's region were found in CAH compared to PAI women, but not in men. Prednisolone treatment showed significant lower osteocalcin levels and lower Z-scores for lumbar spine and femoral neck compared to PAI patients on hydrocortisone. PAI women treated with DHEA had significantly lower urinary collagen crosslinks and bone alkaline phosphatase, and significantly higher Z-scores in lumbar spine and femoral Ward's region compared to non-DHEA-treated women.

CONCLUSIONS: Adult PAI and CAH patients on low glucocorticoid doses showed normal BMD within the normal reference range. The use of longer acting prednisolone resulted in significantly lower BMD in PAI. In addition, DHEA treatment may have a beneficial effect on bone in Addison's women.