The Effects of Parathyroid Hormone, Alendronate, or Both in Men with Osteoporosis

Because parathyroid hormone increases both bone formation and bone resorption, it is possible that combining parathyroid hormone with an antiresorptive agent will enhance its effect on bone mineral density.

We randomly assigned 83 men who were 46 to 85 years of age and had low bone density to receive alendronate (10 mg daily; 28 men), parathyroid hormone (40 microg subcutaneously daily; 27 men), or both (28 men). Alendronate therapy was given for 30 months; parathyroid hormone therapy was begun at month 6. The bone mineral density of the lumbar spine, proximal femur, radial shaft, and total body was measured every six months with the use of dual-energy x-ray absorptiometry. Trabecular bone mineral density of the lumbar spine was measured at base line and month 30 by means of quantitative computed tomography. Serum alkaline phosphatase levels were measured every six months. The primary end point was the rate of change in the bone mineral density at the posteroanterior spine.