Purpose: The purpose of this study was to evaluate the effects of alendronate on bone mineral density (BMD) and to determine the persistency and side effects of alendronate treatment after hip fractures.
Materials and Methods: 452 patients who underwent surgery for hip fractures from March 2000 to February 2007 were retrospectively included. The hip fractures consisted of 218 cases of femur neck fractures and 234 cases of intertrochanteric fractures. There were 254 women and 198 men with a mean age of 73.4 years (range: 60~95 years) at the time of surgery. The BMD was assessed in 398 patients and 348 were diagnosed with osteoporosis, while 102 received alendronate for treatment. The persistency with alendronate treatment and change of the BMD were evaluated annually. We also evaluated the side effects and reasons for discontinuation.
Results: The prescription rate of alendronate was 29.3% and the persistency rate over 1 year was 33%. The annual BMD of the lumbar spine showed a 9.11% increase the first year, a 4.5% increase the second year and a 3.5% increase the third year, while negative changes were noted in the proximal femur as a 1.89% decrease the first year, a 1.38% decrease the second year and a 0.97% decrease the third year. The BMD changes were 11%(L: Lumbar spine) and 1.1%(F: Femur) for the T-scores <-4.0, 6.3%(L) and 0.9%(F) for the T-scores -3.0~-4.0, and 3.8%(L) and -3.5%(F) for the T-scores >-3.0, respectively. The BMD changes in the patients with femur neck fractures and who were treated with hemiarthroplasty were 15.6%(L) and -3.9%(F). The BMD changes in the patients with intertrochanteric hip fractures and who were treated with compression hip screws or hemiarthroplasty were 18.7%(L), 0.77%(F), 24.2%(L) and 1.19%(F), respectively. Gastrointestinal problems(19.1%) were the most common cause for discontinuation of alendronate.
Conclusion: It is important for doctors to approach osteoporosis more carefully and educate patients to follow the prescriptions in order to improve the low prescription and persistency rates for the management of osteoporotic hip fractures. Administration of alendronate may have a positive influence on the BMD of the proximal femur by lowering the rate of decreased BMD more than would be expected.

Keywords: Hip fracture, Bone mineral density, Alendronate, Persistency