Breast cancer survivors are at an increased risk for osteoporotic fractures not explained by lower BMD: a retrospective analysis

Abstract

Background:An association between higher bone mineral density (BMD) and the diagnosis of breast cancer (BC) has been reported. Data on the risk of osteoporotic fractures in women with BC are conflicting.Aims:The objective of this study was to assess fracture risk adjusted for BMD in women with and without BC, and to assess whether fracture risk in BC patients is attributed to BMD or BC characteristics.Methods:Using electronic medical records of patients who underwent dual energy X-ray absorptiometry BMD studies at Soroka University Medical Center between February 2003 and March 2011, we identified women with subsequent diagnosis of osteoporotic fractures. BC status, demographic, health characteristics, BMD, and other laboratory findings were assessed. In BC patients data on grade, stage, and treatment were collected. Primary outcome was osteoporotic fracture, analyzed by Cox proportional hazards regression models.Results:During a median follow-up of 4.9 years in 17,110 women with BMD testing (658 BC patients), 1,193 women experienced an osteoporotic fracture (62 in BC and 1,131 in no-BC groups). In multivariate analysis adjusted for age, body mass index (BMI) and BMD, hazard ratio (HR) for any osteoporotic fracture in women with BC was 1.34 (P=0.026). BMD was similar among women with and without BC who fractured. BC patients who experienced an osteoporotic fracture had a trend for less-advanced BC, lower rates of chemotherapy treatment, and higher rates of tamoxifen treatment.Conclusions:BC survivors are at increased risk of an osteoporotic fracture, which is not explained by worse BMD. Chemotherapy or aromatase inhibitors did not contribute substantially to fracture risk among our BC survivors.

DIAGNOSIS OF ENDOCRINE DISEASE: Evaluation of bone fragility in endocrine disorders

“…The increased awareness about CTIBL has led to guidelines and expert panel to recommend to monitor for bone loss with BMD by DXA (107). However in a retrospective study on 17,110 breast cancer survivor followed about 5 years demonstrated that the increased risk of a fracture was not explained by worse BMD suggesting that BMD does not adequately capture bone strength determinants as shown in other studies (108). When postmenopausal women with breast cancer treated with aromatase inhibitors were randomised to receive placebo or denosumab, the risk of all fracture in placebo group and the risk of fracture reduction in denosumab group were substantially independent of BMD (104).…”

Fracture risk in breast cancer: Does obesity have an effect? A scoping review

“…It was suggested that BC survivors are at an increased risk of fracture. Hazard ratio (HR) for any osteoporotic fracture in women with BC was 1.34 (P = 0.026) that was not explained by bone mineral density (BMD) but other processes that affect bone quality such as obesity [18] . In a single-centre, cross-sectional study examining the association of fat body mass with vertebral fractures in postmenopausal women with BC, Pedersini et al stratified participants treatment according to whether they were aromatase inhibitor naive or had been taking aromatase inhibitors for at least 2 years.…”

“…All 5 studies examined the association between BMI and fracture risk [18] , [19] , [20] , [21] , [22] . Two studies were from the US [20] , [22] , one from Italy [19] , one from Israel [18] and one from China [21] . All studies were conducted among mature females with breast cancer (over 18).…”

Risk of Osteoporotic Fracture in Patients with Breast Cancer: Meta-Analysis

“…The remaining 4 studies fulfilling all inclusion criteria were reviewed. [20][21][22][23] One was from China, 1 from Taiwan, 1 from the UK, and 1 from Israel. These studies involving 127,722 participants were identified for the meta-analysis.…”

“…Fraenkel et al [20] performed a case control cross-sectional, retrospective study to determine whether breast cancer was associated with osteoporotic fracture in 17,110 women with a BMD test between 2003 and 2011. Among 1,193 women with osteoporosis, 62 had a previous history of breast cancer while the remaining 131 did not.…”