Aromatase Inhibitor-Associated Bone Loss

Abstract

Aromatase inhibitors (AIs) are standard treatments for postmenopausal women with estrogen responsive breast cancers. The mechanism of AIs, inhibition of the aromatase enzyme that causes decreases in endogenous estrogens, is responsible for bone loss and increased fractures. Screening and prevention of AI-induced bone loss closely follows the standard recommendations for postmenopausal osteoporosis. Lifestyle changes such as increasing physical activity and weight-bearing exercise, stopping smoking, and taking adequate amounts of daily calcium and vitamin D promote bone and overall health. Bisphosphonates are specific inhibitors of osteoclasts and reduce bone loss in women treated with AIs. The optimal dose administration schedule and duration of bisphosphonate treatment for AI-induced bone loss remains undefined.