Bone mineral density screening among women with a history of breast cancer treated with aromatase inhibitors

The impact of bone mineral density screening on incident fractures and healthcare resource utilization among postmenopausal breast cancer survivors treated with aromatase inhibitors

Bone mineral density screening prior to initiating aromatase inhibitor therapy was associated with lower incident bone fractures and healthcare resource utilization among postmenopausal breast cancer survivors.

INTRODUCTION

Postmenopausal women with hormone receptor-positive breast cancer (BC) often receive aromatase inhibitor (AI) therapy. However, AIs induce bone loss and BC survivors are at an increased risk of bone fractures. This study determined whether receipt of baseline dual-energy x-ray absorptiometry (DXA) screening is associated with decreased incident fractures and lower healthcare resource utilization.

METHODS

We retrospectively analyzed 22,713 stage 0-III primary BC survivors who received AI therapy ≤ 1 year prior to BC diagnosis from the Medicare-Linked Surveillance, Epidemiology, and End-Results database. We categorized DXA screening for those who had a procedural claim within 12 months prior through 6 months after first AI claim. We used propensity score methods to assess the association of DXA screening with bone fractures and health resource utilization.

RESULTS

Of the study cohort, 62% received a DXA screening. Women with comorbid dementia, renal disease, and congestive heart failure were less likely to receive a DXA. After adjusting for confounders, BC survivors who received a DXA had a 32% decreased risk of any bone fracture compared to those who did not (hazard ratio (HR): 0.68, 95% confidence interval (CI): 0.60-0.76, p < 0.001). Similarly, those who received a DXA were less likely to be hospitalized (HR 0.73 (0.62-0.86)) or use outpatient services (HR 0.85 (0.74-0.97)).

CONCLUSIONS

Bone density screening is associated with decreased incident bone fractures and a lower likelihood of utilizing healthcare resource for fracture-related events. Postmenopausal BC survivors treated with AIs should undergo appropriate bone density screening to reduce morbidity, mortality, and health care expenses.

Attention to bone health in follow-up of gynaecological cancers in tertiary care

OBJECTIVE

Women with gynaecological cancers are at an increased risk of cancer treatment-induced bone loss, which impacts on their quality of life and overall survival. Clinical cancer follow-up reviews focus on cancer status and fail to attend to important health and quality-of-life issues. We questioned whether there was a care-gap between tertiary clinicians and primary care physicians in the management of bone health in this cohort. Significant care-gaps in relation to bone health have been demonstrated in other oncologic settings. The objective of this study was to determine the level of attention to bone health in the care of women living with and beyond gynaecological cancer at a tertiary referral centre for gynaecological oncology.

METHODS

Retrospective, observational cohort study of attention to bone health in the management and follow-up of gynaecological cancers.

RESULTS

This study shows that there has been suboptimal attention from the carers at a cancer centre to bone health during the oncological follow up of women undergoing treatment for gynaecological cancer. In those at particular risk of cancer treatment-induced bone loss (iatrogenic menopause and/or external beam pelvic radiotherapy), 52% of women had no reference to bone health in their notes, and 57% had no assessment of bone mineral density.

CONCLUSION

Tertiary cancer carers may underestimate the importance of bone health or believe that it falls outside the remit of their gynaecologic oncology service. Further research is needed to explore whether these findings are indicative of a true care gap and to gain insight into possible corrective measures.

Bone Mineral Density at the Time of Initiating Aromatase Inhibitor Therapy Is Associated With Decreased Fractures in Women With Breast Cancer

Women with estrogen receptor-positive breast cancer who receive an aromatase inhibitor (AI) are at risk for fractures. We aim to determine if dual-energy X-ray absorptiometry (DXA) scans made at the time of AI initiation are associated with decreased fractures. We retrospectively identified 25,158 women with local or regional breast cancer diagnosed between 2005 and 2013 who received AI therapy between 2007 and 2013 from the Medicare-linked Surveillance, Epidemiology, and End Results Program and Texas Cancer Registry databases. We defined baseline DXA screening using claims made between 1 year before and 6 months after each patient's first AI claim to examine determinants of baseline screening using a multivariable GENMOD model. We included a propensity score adjustment in Cox proportional hazard models to assess the association between time-varying DXA screening and the risk of fractures. Additionally, we compared the use of antiresorptive therapy drugs between the two groups. Of the study cohort, 14,738 (58.6%) received DXA screening. The screening rates increased annually from 52.1% in 2007 to 61.7% in 2013. Higher screening rates were observed in patients with younger age, married status, non-Hispanic white race, localized disease, fewer comorbidities, more than one type of aromatase inhibitor drug claim, no state buy-in (surrogate for low socioeconomic status), higher education level, and prior osteoporosis diagnosis. Baseline DXA screening was associated with decreased risk of subsequent fractures (hazard ratio = 0.91; 95% confidence interval, 0.86-0.97, p < .001) after multivariable and propensity score adjustment. Bone-modifying drugs were prescribed to 4440 (30.1%) patients with screening compared with 1766 (16.9%) without (p < .001). Of the 4440 patients who received treatment, 95% received bisphosphonates. Our study demonstrated baseline DXA screening was associated with a decreased risk of fractures and a higher likelihood of receiving antiresorptive therapies. Improvement of the baseline DXA screening is still needed in practice. © 2021 American Society for Bone and Mineral Research (ASBMR).

Hormone therapy and osteoporosis in breast cancer survivors: assessment of risk and adherence to screening recommendations

The long-term impact of hormone therapy for breast cancer on risk of osteoporosis and the extent to which bone screening recommendations are implemented in daily practice remain unknown. We found that the aromatase inhibitor-induced risk of osteoporosis did not continue in the off-treatment follow-up. Adherence to screening recommendations was suboptimal.

INTRODUCTION

A case-cohort study was undertaken to better understand the impact of hormone therapy on breast cancer patients' risk of osteoporosis, and to estimate the extent to which current bone mineral density screening recommendations are implemented in real-life daily practice.

METHODS

This study is based on 1692 female breast cancer survivors recruited from "Leumit" healthcare fund, who were diagnosed with primary nonmetastatic invasive breast cancer between 2002 and 2012. A 20% random subcohort was sampled at baseline, and all osteoporosis cases were identified. Adjusted hazard ratios (HR) with 95% confidence intervals (CI) were estimated by weighted Cox proportional hazards models.

RESULTS

Of 1692 breast cancer survivors, 312 developed osteoporosis during a median follow-up of 5 years. The crude cumulative incidence of osteoporosis accounting for death as a competing risk was 25.7% (95% CI, 21.9-29.5%). In multivariable analyses, osteoporosis was positively associated with the aromatase inhibitor (AI) sequential treatment after tamoxifen (HR, 3.14; 95% CI, 1.44-6.88; P = .004) but was more pronounced with AI use as upfront monotherapy (HR, 5.53; 95% CI, 1.46-20.88; P = .012). This effect did not continue in the off-treatment follow-up. In subgroup analysis by menopausal status, tamoxifen did not seem to confer a protective effect on bone health in postmenopausal patients. Adherence to screening recommendations in AI-treated postmenopausal women was suboptimal, particularly at baseline and after 48 months of continuous AI use.

CONCLUSIONS

The natural, age-related reduction in bone density is exacerbated by breast cancer active AI treatment. Future research should focus on investigating screening adherence-related barriers/facilitators and effective strategies to bring practice in line with agreed standards.

Divergence from osteoporosis screening guidelines in older breast cancer patients treated with anti-estrogen therapy: A population-based cohort study

PURPOSE

Older Breast Cancer (BC) survivors are an increased risk of osteoporosis due to natural aging and long-term cancer treatment-related toxicity. It is well known that anti-estrogen therapy (AET), especially aromatase inhibitors (AI), is associated with rapid bone loss and thus increases the risk of osteoporosis. This study characterizes patterns and predictors of receiving guideline-recommended bone densitometry (BD) screening at AET initiation.

METHODS

A retrospective cohort study (1998-2012) of all women ≥65 years of age initiating AET was designed using claims data from Quebec's universal health care. Associations with BD screening were estimated using a generalized estimating equations regression model, adjusting for clustering of patients within physicians.

RESULTS

Among 16,480 women initiating AET, 36.1% received a baseline BD. Among AI users, the rate was 58.4%. In the multivariate analysis, age, lower socioeconomic status, tamoxifen use, lack of periodic health exam and having a general practitioner as the AET prescriber were associated with lower odds of BD screening. In terms of quality of care-related variables, lack of guideline-appropriate radiotherapy (OR: 0.69 (95% CI, 0.57-0.83), or chemotherapy consideration (0.82 (95% CI, 0.71-0.94)) and non-adherence to AET (0.76 (95% CI, 0.68-0.84)) were associated with lower odds of receiving BD screening. Women diagnosed with BC after 2003 had significantly better odds of being screened.

CONCLUSION

Despite an increase in rates since 2003, BD screening remains suboptimal, especially for women at higher risk of osteoporosis. Coordination of health care and service-delivery monitoring can potentially optimize long-term management of treatment-related toxicity in older BC survivors.

Mind the (treatment) gap: a global perspective on current and future strategies for prevention of fragility fractures

This narrative review considers the key challenges facing healthcare professionals and policymakers responsible for providing care to populations in relation to bone health. These challenges broadly fall into four distinct themes: (1) case finding and management of individuals at high risk of fracture, (2) public awareness of osteoporosis and fragility fractures, (3) reimbursement and health system policy and (4) epidemiology of fracture in the developing world. Findings from cohort studies, randomised controlled trials, systematic reviews and meta-analyses, in addition to current clinical guidelines, position papers and national and international audits, are summarised, with the intention of providing a prioritised approach to delivery of optimal bone health for all. Systematic approaches to case-finding individuals who are at high risk of sustaining fragility fractures are described. These include strategies and models of care intended to improve case finding for individuals who have sustained fragility fractures, those undergoing treatment with medicines which have an adverse effect on bone health and people who have diseases, whereby bone loss and, consequently, fragility fractures are a common comorbidity. Approaches to deliver primary fracture prevention in a clinically effective and cost-effective manner are also explored. Public awareness of osteoporosis is low worldwide. If older people are to be more pro-active in the management of their bone health, that needs to change. Effective disease awareness campaigns have been implemented in some countries but need to be undertaken in many more. A major need exists to improve awareness of the risk that osteoporosis poses to individuals who have initiated treatment, with the intention of improving adherence in the long term. A multisector effort is also required to support patients and their clinicians to have meaningful discussions concerning the risk-benefit ratio of osteoporosis treatment. With regard to prioritisation of fragility fracture prevention in national policy, there is much to be done. In the developing world, robust epidemiological estimates of fracture incidence are required to inform policy development. As the aging of the baby boomer generation is upon us, this review provides a comprehensive analysis of how bone health can be improved worldwide for all.

Bone Density Screening in Postmenopausal Women With Early-Stage Breast Cancer Treated With Aromatase Inhibitors

PURPOSE

In postmenopausal women with breast cancer treated with aromatase inhibitors (AIs), most expert panels advise baseline bone mineral density testing with a dual-energy x-ray absorptiometry (DXA) scan repeated every 1 to 2 years. How often this recommendation is followed is unclear.

METHODS

We performed a retrospective analysis of women with stage I to III breast cancer who started AI therapy from January 1, 2008, to December 31, 2010, with follow-up through December 31, 2012, by using the SEER-Medicare database. Selection criteria included AI use for ≥ 6 months and no recent osteoporosis diagnosis or bisphosphonate use. We used multivariable logistic regression to investigate associations between patient characteristics and receipt of a baseline DXA scan. In patients who continued AI treatment, we assessed rates of follow-up scans.

RESULTS

In the sample of 2,409 patients (median age, 74 years), 51.0% received a baseline DXA scan. Demographic characteristics associated with the absence of a baseline DXA scan were older age (85 to 94 years v 67 to 69 years; odds ratio [OR], 0.62; 95% CI, 0.42 to 0.92) and black v white race (OR, 0.68; 95% CI, 0.47 to 0.97). Among patients who underwent a baseline DXA scan and continued AI for 3 years, 28.0% had a repeat DXA scan within 2 years and 65.9% within 3 years. In aggregate, of the 1,164 patients who continued with AI treatment for 3 years, only 34.5% had both a baseline and at least one DXA scan during the 3-year follow-up period.

CONCLUSION

The majority of older Medicare beneficiaries with breast cancer treated with AIs do not undergo appropriate bone mineral density evaluation.

Bone health history in breast cancer patients on aromatase inhibitors

A cross-sectional study was performed to assess bone health history among aromatase inhibitor (AI) users before breast cancer (BC) diagnosis, which may impact fracture risk after AI therapy and choice of initial hormonal therapy. A total of 2,157 invasive BC patients initially treated with an AI were identified from a prospective cohort study at Kaiser Permanente Northern California (KPNC). Data on demographic and lifestyle factors were obtained from in-person interviews, and bone health history and clinical data from KPNC clinical databases. The prevalence of osteoporosis and fractures in postmenopausal AI users was assessed, compared with 325 postmenopausal TAM users. The associations of bone health history with demographic and lifestyle factors in AI users were also examined. Among all initial AI users, 11.2% had a prior history of osteoporosis, 16.3% had a prior history of any fracture, and 4.6% had a prior history of major fracture. Postmenopausal women who were taking TAM as their initial hormonal therapy had significantly higher prevalence of prior osteoporosis than postmenopausal AI users (21.5% vs. 11.8%, p<0.0001). Among initial AI users, the associations of history of osteoporosis and fracture in BC patients with demographic and lifestyle factors were, in general, consistent with those known in healthy older women. This study is one of the first to characterize AI users and risk factors for bone morbidity before BC diagnosis. In the future, this study will examine lifestyle, molecular, and genetic risk factors for AI-induced fractures.

Bone health care for patients with prostate cancer receiving androgen deprivation therapy

Patients with prostate cancer often receive androgen deprivation therapy (ADT) as part of their treatment regimen. However, treatment with ADT causes multiple side effects, including reduced bone mineral density (BMD), lower lean body mass, and a higher risk for fractures. Several organizations provide clinical practice guidelines for osteoporosis screening, prevention, and treatment in this population, but adherence to these guidelines remains low. Areas for improvement in provider adherence include baseline and follow-up BMD testing, as well as counseling regarding healthy bone behaviors such as calcium/vitamin D intake, lifestyle changes, and physical exercise. Comparison of osteoporosis care in breast cancer and non-oncology populations shows that suboptimal bone health care is not isolated to prostate cancer. A summary of the literature examining improvements in patient adherence and provider delivery of bone health care is included in this review, but high-quality studies are lacking. Patients may be the most receptive to written educational information delivered at or near the time of ADT initiation. Involvement of a primary care practitioner and oncologist in care delivery is associated with higher BMD test use. Institution-level programs that automatically initiate osteoporosis screening and management may be effective at reducing the incidence of hip fracture. Lastly, suggestions are provided for future approaches to knowledge translation and quality of care studies to improve bone health.

Osteoporosis and cancer

Cancer is a major risk factor for bone loss and fractures. This is due both to direct effects of cancer cells on the skeleton and to deleterious effects of cancer-specific therapies on bone cells. Marked improvements in survival for many cancers mean that strategies to limit bone loss and reduce fracture risk must be incorporated into the care plans for nearly all patients with cancer. The vast majority of effort thus far has focused on bone loss in patients with breast and prostate cancers, with comparatively few studies in other malignancies. Antiresorptive therapies have proven nearly universally effective for limiting bone loss in cancer patients, although few studies have been powered sufficiently to include fractures as primary endpoints, and patients are frequently neither identified nor treated according to published guidelines. Nonpharmacologic approaches to limit falls, particularly in elderly patients, are also likely important adjunctive measures for most cancer patients.