In a retrospective study, we studied the medical notes of 35 patients with adrenal insufficiency; aged 61±15 (mean ±S.D.) years. Their average age at diagnosis was 45±18 years, and duration of the disease was 17±15 years.
Most patients were on hydrocortisone replacement (32 patients); taking 23±4 mg daily in divided doses, and only 3 (9%) patients were on single dose of prednisone 7.5±05 mg daily in a single dose. Average body weight at diagnosis was 66±15 years, and last body at time of this study was 75±15 years.
Thirty patients (86%) have reduced bone density on Dual-energy absorptiometry (BMD) scan, 14 patients have osteoporosis and 16 had osteopenia. The t-score spine and hip were reduced, but were both marginally higher at diagnosis compared to time of study, but the difference was not significant (−1.6±0.8 vs −1.3±0.7) and (−1.6±0.8 vs 1.15±0.7) respectively. The Z-score of hip and spine were also reduced. There was no difference in the daily hydrocortisone dose in patients with osteoporosis (13 patients), compared to the 19 patients on hydrocortisone with no osteoporosis (22.2 vs 24.2 mg daily). Conversely, when we stratified the hydrocortisone dose cohort into those with total daily dose of 20 mg (17 patients), 25 (9 patients) and 30 mg (6 patients), the prevalence of reduced bone density was 52.9% (9), 33.3% (3) and 16.7% (1) (Pearson χ2 P=0.26). Among the three patients receiving prednisolone only one had osteoporosis (total daily dose=8 mg).
In conclusion, osteoporosis and osteopenia were very common (85.7%) in those with adrenal insufficiency. No correlation was identified between the dose of steroid replacement and the prevalence of reduced bone density.