BONE MINERAL DENSITY IN PATIENTS WITH ADDISON DISEASE ON REPLACEMENT THERAPY WITH PREDNISOLONE

In primary adrenal insufficiency (PAI), replacement with prednisolone may result in lower bone mineral density (BMD) compared with hydrocortisone therapy. However, the number of patients studied on prednisolone is small and the results are conflicting. We conducted a cross-sectional study to determine BMD and its relation with therapy in patients on physiologic doses of prednisolone replacement.

Forty-one consecutive patients (31 males, age [mean ± SD] 50.9 ± 13.0 years), receiving prednisolone (hydrocortisone equivalent [HCE] 13.0 ± 3.0 mg/m(2)) for 104 ± 95 months were studied. BMD was evaluated by dual-energy X-ray absorptiometry and compared with an age- and sex-matched reference group of healthy Indian subjects (n = 677).

Among males, BMD Z-scores (mean [95% confidence interval {CI}]) at lumbar spine (-0.42 [-0.80, -0.04]), femoral neck (-0.50 [-0.95, -0.06]) and total hip (-0.58 [-0.90, -0.26]) were significantly lower than the reference population. Z-scores in female patients did not differ from controls. Among postmenopausal females and males >50 years, 43% had osteoporosis (T-score ≤-2.5), as compared with 25% in the reference group (P = .04). There was no correlation between BMD Z-scores and HCE dose or duration of therapy. On multivariate regression analysis, body mass index was the only significant predictor of BMD. A high proportion of males (45%) had low serum testosterone (<300 ng/dL), but there was no correlation between testosterone and BMD.

Male patients with PAI receiving physiologic prednisolone replacement had a small but significant diminution in BMD at all sites.