Objective: To compare the effects of calcitonin, etidronate, and alendronate in preventing bone loss during the first 2 years after heart transplant.
Methods: A total of 222 heart transplant recipients (mean [SD] age, 52.4 [10] years, 85% male) were evaluated. Patients with normal bone mineral density (reference group, n = 102) received 1000 mg/d calcium plus 800 IU/d vitamin D3. The rest were assigned to 200 IU/d of calcitonin (n=42), 400 mg/d etidronate orally for 14 days quarterly (n = 33), or 10 mg/d alendronate (n = 45). All patients received calcium and vitamin D. Bone mineral density was assessed by dual-energy x-ray absorptiometry in the lumbar spine, the entire femur, and the femoral neck at baseline and 6, 12, and 24 months after transplant.
Results: At 2 years after transplant, bone mineral density in the lumbar spine had decreased in the reference group (-3.07%), calcitonin group (-0.93%), and etidronate group (-1.87%) but not in the alendronate group (+4.9%; P <.001). After 2 years, bone mineral density in the entire femur decreased in all groups (-3.2% in the reference group, -3.6% in the calcitonin group, -4.6% in the etidronate group, and -0.5% in the alendronate group) but bone loss was significantly lower in the alendronate group (P <.001). Bone mineral density in the femoral neck also decreased in all groups. The incidence of vertebral fractures did not differ among groups. Adverse events were similar between groups.
Conclusions: Alendronate therapy in heart transplant recipients was associated with a significant increase in bone mineral density in the lumbar spine and less bone loss at the hip.