The Association Between Aromatase Inhibitors Initiation and Bone Health Assessment in Early Hormonal Positive Breast Cancer Patients: A Registry-based Cohort Study
2Maccabitech institute for research and innovation, Maccabi Healthcare Services
3Epidemiology Department, School of Public Health, Sackler Faculty of Medicine, Tel Aviv University
Aim:
To assess bone health evaluation and fracture prevention strategies in postmenopausal women with estrogen receptor (ER)-positive breast cancer after AIs initiation.
Methods:
An historical cohort analysis based on data from the cancer and osteoporosis Maccabi Health Services (MHS) registries from Jan 1st 2009 to Dec 31st 2019. Cases of estrogen receptor (ER)-positive breast cancer, early stages (1 to 3) were extracted. Index date was set as the first aromatase inhibitors (AI) purchase. BMI, smoking history, alcohol use, previous fractures, BMD T-scores, purchases of AI and anti-resorptive agents were collected. Kaplan-meier curves were generated to assess the time to outcomes.
Results:
A total of 7816 women were eligible, mean (SD) age at index was 64 (9.8), mean BMI 28.7 (5.4). One year after AI initiation 21% had a BMD measurement, the mean time to DXA was 2.2 (1.9) years from index. The mean lumbar spine T-score was -1.3 (1.3), mean Femoral Neck T-score -1.5 (1.3) and the mean Total Hip T-score -1.0 (1.0).
The proportion of patients treated was 38.6% and the mean time to an antiresorptive prescription was 1.58 (1.3) years. The most prevalent treatment was Alendronate (34%), followed by Risedronate (23%), Zoledronic acid (21%) and Denosumab (6%). The mean time to fracture was 6.7 (4.6) years with a cumulative incidence of 1.7% at five years.
Conclusions:
Despite the well-known excess risk for fractures of breast cancer AI treated patients, bone health assessment and preventive treatment are still partial and postponed. Strategies to increase awareness are needed.
