Fracture incidence after 3 years of aromatase inhibitor therapy

Abstract

Background: The purpose of this study was to describe the fracture incidence and bone mineral density (BMD) evolution in a large cohort of post-menopausal women with breast cancer after 3 years of aromatase inhibitor (AI) therapy. Patients and methods: A prospective, longitudinal study in real-life setting. Each woman had an extensive medical assessment, a biological evaluation, a BMD measurement, and systematic spinal X-rays at baseline and after 3 years of AI therapy. Women with osteoporosis at baseline (T-score < 0.01), neck BMD (-2.0%, P < 0.01), and total hip BMD (-2.1%, p < 0.01) over the 3 years but only 15 of them (5.6%) presented an incident vertebral or nonvertebral fracture. In osteoporotic women treated with bisphosphonates, spine and hip BMD were maintained at 3 years but 12 of them (9.8%) had an incident fracture. These fractured women were significantly older (74.1 ± 9.8 versus 66.5 ± 8.8) but also presented BMD loss during treatment suggesting poor adherence to bisphosphonate treatment. Conclusion: This real-life study confirmed that AIs induced moderate bone loss and low fracture incidence in postmenopausal women without initial osteoporosis. In women with baseline osteoporosis and AI therapy, oral bisphosphonates maintain BMD but were associated with a persistent fracture risk, particularly in older women. © The Author 2014. Published by Oxford University Press on behalf of the European Society for Medical Oncology. All rights reserved.