Fractures in a nationwide population-based cohort of users of breast cancer hormonal therapy. J Cancer Surviv 2018 Apr;12(2):268-275
Date
12/16/2017Pubmed ID
29243101DOI
10.1007/s11764-017-0666-4Scopus ID
2-s2.0-85038093950 (requires institutional sign-in at Scopus site) 8 CitationsAbstract
PURPOSE: Although users of aromatase inhibitors have higher total fracture risk in some randomized trials, little is known about their risk outside of clinical trials or in older higher-risk cohorts.
METHODS: In a population-based retrospective cohort study, we identified all older US Medicare D prescription drug insurance plan-enrolled women who had initial breast cancer surgery in 2006-2008 and began hormonal therapy (an aromatase inhibitor (AI) or tamoxifen) within the subsequent year. Total nonvertebral and hip fractures through 2012 were identified using a validated algorithm. The association of fracture outcomes with hormonal therapy type was assessed using competing risk regression models that accounted for differences in measured baseline covariates. Treatment assignment bias was reduced using inverse probability of treatment weighting computed from propensity scores.
RESULTS: Among 23,378 women taking hormonal therapy (23.2% aged 80 or over), there were 3000 total and 436 hip fractures. Although AI users were younger and had lower comorbidity, after propensity score weighting, these and other covariates were balanced. Total nonvertebral risk was higher for users of AIs compared with tamoxifen, HR 1.11 (1.02-1.21), but the small increase in risk for hip fracture was not statistically significant, HR 1.04 (0.84-1.30).
CONCLUSIONS: Although total nonvertebral fracture risk was higher among AI users, differences in hip fractures were not significant in a large population-based cohort of older women.
IMPLICATIONS FOR CANCER SURVIVORS: Use of aromatase inhibitors by older women is associated with high risk for nonvertebral fracture that is increased compared with use of tamoxifen. Fracture risk should be assessed among patients taking these medications.
Author List
Neuner JM, Shi Y, Kong AL, Kamaraju S, Smith EC, Smallwood AJ, Laud PW, Charlson JAAuthors
John A. Charlson MD Associate Professor in the Medicine department at Medical College of WisconsinSailaja Kamaraju MD Associate Professor in the Medicine department at Medical College of Wisconsin
Amanda L. Kong MD, MS Professor in the Surgery department at Medical College of Wisconsin
Purushottam W. Laud PhD Professor in the Institute for Health and Equity department at Medical College of Wisconsin
Joan Neuner MD, MPH Professor in the Medicine department at Medical College of Wisconsin
MESH terms used to index this publication - Major topics in bold
AgedAged, 80 and over
Antineoplastic Agents, Hormonal
Aromatase Inhibitors
Breast Neoplasms
Cancer Survivors
Cohort Studies
Female
Fractures, Bone
Hip Fractures
Humans
Medicare
Retrospective Studies
Tamoxifen
United States
