[Clinical application of alendronate for osteoporosis/osteopenia secondary to hyperthyroidism]

To evaluate the efficacy and safety of alendronate for the treatment of osteoporosis/osteopenia secondary to hyperthyroidism.

From April 2008 to November 2009, 27 patients with hyperthyroidism with osteoporosis/ osteopenia measured by dual energy X-ray absorptiometry (DXA) were included in this study, and then they were randomly divided into two groups (group A and group B) by simple random sampling. Group A consisted of 14 patients treated with antithyroid drug and caltrate D, the antithyroid drug change with thyroid function, and caltrate D 600 mg per day. Group B consisted of 13 patients treated with antithyroid drug, caltrate D and alendronate, antithyroid drug and caltrate D the same as group A, and alendronate 70 mg weekly. Meanwhile, 21 healthy voluntary adults were chosen as control group. And compared with the control group which was treated with nothing. Followed-up for one year, the bone mineral density (including T-score, Z-score, BMD) in lumbar spine (LS), femoral neck (FN) and distal radius (DR) and general information, were compared before and after treatment.

BMD at FN and DR were significantly higher at 12 months after treatment than at the baseline in group A (P = 0.000); T-score, Z-score, and BMD at the LS, FN and DR were all significantly higher at 12 months after treatment than at the baseline in group B (P < 0.05), but these data could not arrive to normal level. In group A, the percentage increased in BMD at the LS, FN, and DR were (4.34 +/- 10.5)%, (3.21 +/- 1.38)%, (1.95 +/- 0.44)%, respectively, at 12 months after treatment. In group B, the percentage increased in BMD at the LS, FN, and DR were (6.10 +/- 8.12)%, (4.10 +/- 5.64)%, (3.10 +/- 3.23)%, respectively, at 12 months after treatment. There was significant difference in the rate of increase between two groups (P < 0.05). AKP decreased, weight, BMI increased, and thyroid function decreased, after treatment than those before in both of the two groups. (P < 0.05).

Alendronate can significantly increase BMD in treating patients with hyperthyroidism and osteoporosis/osteopenia. Compared with anti-thyroid drugs alone, treatment with alendronate can obtain more clinical effect and also very safety.