ABSTRACT
Background
Hormone therapy with aromatase inhibitors (AIs) for estrogen receptor-dependent breast cancer may expose patients to an increased osteoporosis risk. This study was performed to estimate fracture risk in women with breast cancer to whom AIs were prescribed in Japan.
Methods
This retrospective study used data from the Japanese Medical Data Vision database. Women with breast cancer prescribed AIs over a 12-month period were identified and matched to women not prescribed AIs using a propensity score. Fracture rates were estimated by a cumulative incidence function and compared using a cause-specific Cox hazard model. The proportion of women undergoing bone density tests was retrieved.
Results
For all fractures sites combined, cumulative fracture incidence at 10 years was 0.19 [95%CI: 0.16–0.22] in women prescribed AIs and 0.18 [95%CI: 0.15–0.21] without AIs. AI prescription was not associated with any changes in risk (adjusted hazard ratio: 1.08 [95%CI: 0.99–1.17] p = 0.08). Women prescribed AI more frequently underwent bone density testing (31.9% [95% CI: 31.2%; 32.6%] versus 2.2% [95% CI: 2.0%; 2.4%]).
Conclusions
The anticipated association between AI exposure and osteoporotic fracture risk in Japanese women with breast cancer was not seen clearly.
Abbreviations
AI | = | Aromatase Inhibitor |
ATC | = | Anatomical Therapeutic Chemical |
BMD | = | Bone Mineral Density |
CI | = | Confidence Interval |
DPC | = | Diagnosis Procedure Combination |
ER | = | Estrogen Receptor |
HR | = | Hazard Ratio |
ICD-10 | = | International Classification of Diseases, 10th Edition |
IQR | = | Interquartile Range |
JSBMR | = | Japanese Society for Bone and Mineral Research |
MDV | = | Medical Data Vision |
SD | = | Standard Deviation |
SERM | = | Selective Estrogen Receptor Modulator |
SMD | = | Standard Mean Difference |
VR | = | Variance Ratio |
Declaration of interest
T Taguchi has received consulting fees from Daiichi Sankyo Co., Ltd., speaking fees from Pfizer and Asahi Kasei Pharma Corporation. H Matsushima has received consulting fees, speaking fees or honoraria from Daiichi Sankyo Co., Ltd. S Fukumoto has received consulting fees, speaking fees or honoraria from Daiichi Sankyo Co., Ltd. T Matsumoto has received consulting fees, speaking fees or honoraria from Amgen Inc., Astellas Pharma Inc., Daiichi Sankyo Co., Ltd. and Chugai Pharmaceutical Co., Ltd.
S Kodama and N Okubo and T Ito are employees of Daiichi Sankyo Co., Ltd., a pharmaceutical company which markets medications for the treatment of osteoporosis. M Ludwikowska is an employee of Putnam PHMR, a consultancy company who received funding from Daiichi Sankyo Co., Ltd. for the implementation of this study.
The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.
Author contributions
All authors are responsible for the work described in this paper. T Taguchi, H Matsushima, S Fukumoto, T Matsumoto, M Ludwikowska, S Kodama, N Okubo and T Ito were involved in the conception, design or planning of the study. T Taguchi, H Matsushima, S Fukumoto, T Matsumoto, S Kodama, N Okubo and T Ito interpreted the study results. All authors contributed to critical review and approved the final manuscript.
Acknowledgments
The authors thank Dr. Adam Doble of Foxymed for medical writing.
Study Registration
University Hospital Medical Information Network Clinical Trials Registry: identifier UMIN000048942.
Reviewer disclosures
Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.
Supplementary material
Supplemental data for this article can be accessed online at https://doi.org/10.1080/14656566.2024.2340712