An osteoporosis drug that has been linked to saving lives after a hip fracture may be effective because it strengthens the immune system, researchers at Duke University say. Previous research at Duke found that patients who were treated with Reclast within 90 days after a hip fracture were less likely to die and less likely to suffer another fracture in the following year. Scientists assumed the reduced death risk was because of the lower risk of later fractures, but a new study found that is...