Bone mineral density in relation to glucocorticoid substitution therapy in adult patients with 21-hydroxylase deficiency

OBJECTIVE There are only limited data on bone mineral density (BMD) in adult patients with 21-hydroxylase deficiency (21-OHD). We have defined the effects of different glucocorticoid substitution therapies on BMD and body composition in these patients. DESIGN Cross-sectional. PATIENTS Thirty-two adult patients with 21-OHD. MEASUREMENTS Patients were examined auxologically and biochemically. BMD was examined in the left femoral neck and lumbar vertebrae 2-4 (L2-4) with dual X-ray absorptiometry. The results were compared with national reference data. RESULTS Mean height was 170.1 cm (-1.36 standard deviation scores (SDS) for the men and 156.3 cm (-1.68 SDS) for the women. These were significantly less (P < 0.001) than the mean national final heights. Mean BMD Z-score ((raw score - population reference mean)/ SD) was -0.52 in L2-4 and -0.83 in the left femoral neck. Both these values were significantly less than the reference mean values (P = 0.045 and < 0.001, respectively). Both current and long-term mean glucocorticoid doses showed significant negative correlations with BMD in the left femoral neck as well as in L2-4. Patients substituted with hydrocortisone were less often over-treated and had better BMD Z-score means than patients substituted with prednisone, prednisolone or dexamethasone. CONCLUSIONS In the follow-up of patients with 21-hydroxylase deficiency, care needs to be exercised to keep the glucocorticoid substitution dose to a minimum. In most cases decreased bone mineral density is a result of over-substitution.