Detection of Atypical Femur Fractures.

The 2019 International Society for Clinical Densitometry (ISCD) Position Development Conference Task Force for monitoring with dual-energy X-ray absorptiometry (DXA) identified detection of atypical femur fractures (AFFs) as an important topic and established this working group to answer key questions in this area. The authors conducted a systematic review of the literature and deliberated on proposed ISCD positions, which were then reviewed by an external expert panel and vetted at the 2019 ISCD Position Development Conference in Kuala Lumpur on March 23, 2019. This paper summarizes the final ISCD positions and the rationale for supporting these positions. Default-length femur imaging or extended-length femur imaging as well as full-length femur imaging (FFI), both single-energy and dual-energy scans, by DXA can detect abnormalities in the spectrum of AFF. It is important to visually inspect all DXA scans of the hip and femur, and report on findings of focal periosteal and endosteal thickening at the lateral cortex (grade: Good, A, W). FFI is the preferred DXA scan mode for detecting abnormalities in the spectrum of AFF. The FFI report should state the absence or presence of abnormalities in the spectrum of AFF. If focal thickening is present on the lateral cortex, the report should state whether a lucent line is seen (grade: Fair, C, W). The ISCD recommends considering the use of bilateral FFI in patients who are currently or have been in the past year on potent antiresorptive therapy (ie, oral or intravenous bisphosphonate or subcutaneous denosumab therapy) for a cumulative period of 3 or more years, especially those on long-term glucocorticoid therapy (grade: Fair, B, W). More research is needed to determine the role of repeat testing and the optimal time interval for follow-up DXA scans, whether an automated measuring tool would perform better than visual inspection, whether FFI would change patient management and outcomes, and the cost-effectiveness of FFI.

Effect of odanacatib on BMD and fractures: estimates from Bayesian univariate and bivariate meta-analyses.

CONTEXT: Odanacatib (ODN), a selective cathepsin-K inhibitor, was found to increase bone mineral density (BMD); the effect on fractures is based on adverse event reports. OBJECTIVE: To estimate current effects and predict future effects of ODN on BMD and fractures. DATA SOURCES: Electronic databases (Medline, EMBASE, Cochrane Library), conference proceedings, and bibliographies. STUDY SELECTION: Trials that compared ODN 50 mg/wk to placebo for at least 1 year and reported changes in BMD or fractures. Meta-analysis: Two bone outcomes were pooled as independent and as joint outcomes in Bayesian univariate and bivariate random-effects models. DATA SYNTHESIS: Of 32 potentially eligible articles, six citations describing four trials (993 patients) were included. ODN for 3 years increased mean BMD at the lumbar spine by 5.0% (95% credible interval [CrI], 2.7, 7.5), total hip by 3.6% (95% CrI, 1.6, 5.9), and femoral neck (FN) by 3.6% (95% CrI, 1.6, 5.7). In a future trial of 3-year duration, the predicted mean increase in BMD, adjusted for the effect on fractures, was 4.9% for lumbar spine (95% CrI, 2.5, 7.4), 3.4% for total hip (95% CrI, 1.7, 5.2), and 3.5% for FN (95% CrI, 1.8, 5.3). After accounting for the effect on FN BMD, ODN for 3 years was associated with a population odds ratio of 0.38 (95% CrI, 0.1, 0.8). In a future trial, the odds ratio was 0.41 (95% CrI, 0.1, 1.1). The probability of benefit on fractures was 96-99%. The estimates remained robust in sensitivity analyses. CONCLUSIONS: Our analyses suggest that ODN will increase BMD and decrease all fractures in the fracture outcome trial; however, direct demonstration of this antifracture efficacy is needed.

Breast cancer and osteoporosis.

PURPOSE OF REVIEW: Over the past few years, a number of studies have examined the relationship between breast cancer and osteoporosis, the effect of breast cancer treatment on bone health, and the effect of osteoporosis therapies on aromatase inhibitor-induced bone loss and breast cancer recurrence. New guidelines have been released on the prevention of osteoporotic fractures in women with breast cancer who are on aromatase inhibitors for adjuvant therapy. RECENT FINDINGS: Despite common factors linking high bone mineral density and increased risk of breast cancer, women with breast cancer are not protected from osteoporosis or osteoporotic fractures. Recent data suggest that aromatase inhibitors have a detrimental effect on bone mineral density and can increase the risk of fractures. Bisphosphonate therapy not only preserves aromatase inhibitor-induced bone loss, but may also improve disease-free survival and decrease risk of death in select women with breast cancer (i.e., postmenopausal women). SUMMARY: Osteoporosis and breast cancer are common in women, especially in postmenopausal women. Current guidelines suggest that we need to pay special attention to those on aromatase inhibitors to prevent adverse bone outcomes.