Effects of alendronate and alfacalcidol on bone in patients with myasthenia gravis initiating glucocorticoids treatment

OBJECTIVE Glucocorticoids (GCs) are the first-line treatment for myasthenia gravis (MG) and act as long-term immunosuppressants. However, GCs can induce osteoporosis and bone fractures. In this study, we evaluate the effects of oral alendronate and alfacalcidol, or alfacalcidol alone on the bone of Chinese patients with MG who will initiate treatment with GCs. DESIGN AND METHODS A total of 75 patients were included in this 12-month prospective, open-label, single-centre study. Patients with bone mineral density (BMD) T-score less than -1.0 at baseline were treated with 70 mg of alendronate per week. Patients with BMD T-score greater than -1.0 at baseline were included in the alfacalcidol-alone group. Patients in two groups were treated with 0.25 μg of alfacalcidol every other day and 600 mg of calcium daily. RESULTS After 12 months of treatment, the mean BMD of lumbar spine, femoral neck and total hip increased by 3.4% (P = .002), 1.8% (P = .21) and 2.6% (P = .02), respectively, in alendronate group. In alfacalcidol-alone group, the mean BMD of lumbar spine, femoral neck and total hip decreased by 6.1%, 3.2% and 3.3%, respectively (all P