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Observational Study
. 2020 Feb;35(2):291-297.
doi: 10.1002/jbmr.3886. Epub 2019 Oct 31.

Increased Fracture Risk in Women Treated With Aromatase Inhibitors Versus Tamoxifen: Beneficial Effect of Bisphosphonates

Marta Pineda-Moncusí  1 , Natalia Garcia-Giralt  1 , Adolfo Diez-Perez  1   2 , Sonia Servitja  3   4 , Ignasi Tusquets  3   4 , Daniel Prieto-Alhambra  5   6 , Xavier Nogués  1   2
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Free article
Observational Study

Increased Fracture Risk in Women Treated With Aromatase Inhibitors Versus Tamoxifen: Beneficial Effect of Bisphosphonates

Marta Pineda-Moncusí et al. J Bone Miner Res. 2020 Feb.
Free article

Abstract

Aromatase inhibitors have been associated with accelerated bone loss and an increased risk of osteoporotic fractures. Currently, bisphosphonates are recommended to reduce fracture risk in these patients. The aim of this study is to evaluate the fracture risk in breast cancer patients receiving aromatase inhibitors, compared to tamoxifen users, and to assess the effectiveness of oral bisphosphonates in reducing fracture risk. We performed an observational cohort study up to 10 years of follow-up. Data were extracted from primary care records in a population database. Women diagnosed with breast cancer between 2006 and 2015 and treated with tamoxifen or aromatase inhibitors (n = 36,472) were stratified according to low (without osteoporosis diagnosis nor bisphosphonates exposure) or high (with osteoporosis and/or treated with bisphosphonates) fracture risk. Cox models were used to calculate hazard ratios (HR [95% CI]) of fracture from the propensity score-matched patients. Sensitivity analyses account for competing risk of death were performed (subdistribution hazard ratio [SHR] [95% CI]). In postmenopausal women, fracture risk in aromatase inhibitor users showed an HR 1.40 [95% CI,1.05 to 1.87] and SHR 1.48 [95% CI, 1.11 to 1.98], compared to tamoxifen. Observing aromatase inhibitors patients at high risk of fracture, bisphosphonate-treated patients had an HR 0.73 [95% CI, 0.51 to 1.04] and SHR 0.69 [95% CI, 0.48 to 0.98] compared to nontreated. In conclusion, fracture risk in postmenopausal women during aromatase inhibitor treatment, in real-life conditions, was >40% compared to tamoxifen, corroborating previous randomized controlled trials results. In high-risk patients, bisphosphonate users had lower significant fracture incidence during aromatase inhibitor therapy than nonbisphosphonate users. Monitoring fracture risk and related risk factors in aromatase inhibitor patients is advisable. © 2019 American Society for Bone and Mineral Research.

Keywords: AROMATASE INHIBITORS; ESTROGENS AND SERMS; FRACTURE PREVENTION; FRACTURE RISK ASSESSMENT; GENERAL POPULATION STUDIES.

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References

    1. Cuzick J, Sestak I, Baum M, et al. Effect of anastrozole and tamoxifen as adjuvant treatment for early-stage breast cancer: 10-year analysis of the ATAC trial. Lancet Oncol. 2010;11(12):1135-41.
    1. Regan MM, Neven P, Giobbie-Hurder A, et al. Assessment of letrozole and tamoxifen alone and in sequence for postmenopausal women with steroid hormone receptor-positive breast cancer: the BIG 1-98 randomised clinical trial at 8.1 years median follow-up. Lancet Oncol. 2011;12(12):1101-8.
    1. Ryden L, Heibert Arnlind M, Vitols S, Hoistad M, Ahlgren J. Aromatase inhibitors alone or sequentially combined with tamoxifen in postmenopausal early breast cancer compared with tamoxifen or placebo - meta-analyses on efficacy and adverse events based on randomized clinical trials. Breast. 2016;26:106-14.
    1. Goldvaser H, Barnes TA, Seruga B, et al. Toxicity of extended adjuvant therapy with aromatase inhibitors in early breast cancer: a systematic review and meta-analysis. J Natl Cancer Inst. 2018;110(1):31-9.
    1. Kristensen B, Ejlertsen B, Jensen MB, Mouridsen HT. The occurrence of fractures after adjuvant treatment of breast cancer: a DBCG register study. Acta Oncol. 2018;57(1):141-5.

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