Bone mineral density and bone turnover in postmenopausal women treated for breast cancer

A causal relationship between bone mineral density and breast cancer risk: a mendelian randomization study based on east Asian population

BACKGROUND

Breast cancer (BC) poses significant burdens on women globally. While past research suggests a potential link between bone mineral density (BMD) and BC risk, findings remain inconsistent. Our study aims to elucidate the causal relationship between BMD and BC in East Asians using bidirectional Mendelian randomization (MR).

METHODS

Genetic association data for bone mineral density T-scores (BMD-T) and Z-scores (BMD-Z) (Sample size = 92,615) and BC from two different sources (Sample size1 = 98,283; Sample size2 = 79,550) were collected from publicly available genome-wide association studies (GWAS). Single-nucleotide polymorphisms (SNPs) associated with BMD-T and BMD-Z as phenotype-related instrumental variables (IVs) were used, with BC as the outcome. As the primary means of causal inference, the inverse variance weighted (IVW) approach was employed. Heterogeneity analysis was conducted using Cochran's Q test, while MR-Egger regression analysis was implemented to assess the pleiotropic effects of the IVs. Sensitivity analyses were performed using methods such as MR-Egger, weighted median, and weighted mode to analyze the robustness and reliability of the results. The MR-PRESSO method and the RadialMR were used to detect and remove outliers. The PhenoScanner V2 website was utilized to exclude confounding factors shared between BMD and BC. Besides, the Bonferroni correction was also used to adjust the significance threshold. Then, the meta-analysis method was applied to combine the MR analysis results from the two BC sources. Finally, a reverse MR analysis was conducted.

RESULTS

The results of the IVW method were consolidated through meta-analysis, revealing a positive correlation between genetically predicted BMD-T ([Formula: see text], [Formula: see text], [Formula: see text]) and BMD-Z ([Formula: see text],[Formula: see text], [Formula: see text]) with increased BC risk. The Cochran's [Formula: see text] test and MR-Egger regression suggested that neither of these causal relationships was affected by heterogeneity or horizontal pleiotropy. The sensitivity analyses supported the IVW results, indicating the robustness of the findings. Reverse MR analysis showed no causal relationship between BC and BMD.

CONCLUSION

Our MR study results provide evidence for the causal relationship between BMD and BC risk in East Asian populations, suggesting that BMD screening is of great significance in detecting and preventing BC.

Cost-effectiveness analysis of ovarian function preservation with GnRH agonist during chemotherapy in premenopausal women with early breast cancer

STUDY QUESTION

Is it economically worthwhile to use GnRH agonist (GnRHa) to prevent menopausal symptoms (MS) and protect fertility in premenopausal women with breast cancer (BC) during chemotherapy from the US perspective?

SUMMARY ANSWER

It is cost-effective to administer GnRHa during chemotherapy in order to forefend MS in premenopausal patients with BC when the willingness-to-pay (WTP) threshold is $50 000.00 per quality-adjusted life-year (QALY), and to preserve fertility in young patients with BC who undergo oocyte cryopreservation (OC), or no OC, when the WTP thresholds per live birth are $71 333.33 and $61 920.00, respectively.

WHAT IS KNOWN ALREADY

Chemotherapy often results in premature ovarian insufficiency (POI) in premenopausal survivors of BC, causing MS and infertility. Administering GnRHa during chemotherapy has been recommended for ovarian function preservation by international guidelines.

STUDY DESIGN, SIZE, DURATION

Two decision-analytic models were developed, respectively, for preventing MS and protecting fertility over a 5-year period, which compared the cost-effectiveness of two strategies: adding GnRHa during chemotherapy (GnRHa plus Chemo) or chemotherapy alone (Chemo).

PARTICIPANTS/MATERIALS, SETTING, METHODS

The participants were early premenopausal women with BC aged 18-49 years who were undergoing chemotherapy. Two decision tree models were constructed: one for MS prevention and one for fertility protection from the US perspective. All data were obtained from published literature and official websites. The models' primary outcomes included QALYs and incremental cost-effectiveness ratios (ICERs). The robustness of the models was tested by sensitivity analyses.

MAIN RESULTS AND THE ROLE OF CHANCE

In the MS model, GnRHa plus Chemo resulted in an ICER of $17 900.85 per QALY compared with Chemo, which was greater than the WTP threshold of $50 000.00 per QALY; therefore, GnRHa plus Chemo was a cost-effective strategy for premenopausal women with BC in the USA. Probabilistic sensitivity analysis (PSA) results showed an 81.76% probability of cost-effectiveness in the strategy. In the fertility model, adding GnRHa for patients undergoing OC and those who were unable to undergo OC resulted in ICERs of $67 933.50 and $60 209.00 per live birth in the USA, respectively. PSA indicated that GnRHa plus Chemo was more likely to be cost-effective over Chemo when the WTP for an additional live birth exceed $71 333.33 in Context I (adding GnRHa to preserve fertility in young patients with BC after OC) and $61 920.00 in Context II (adding GnRHa to preserve fertility in young patients with BC who cannot accept OC).

LIMITATIONS, REASONS FOR CAUTION

The indirect costs, such as disease-related mental impairment and non-medical costs (e.g. transportation cost) were not included. All data were derived from previously published literature and databases, which might yield some differences from the real world. In addition, the POI-induced MS with a lower prevalence and the specific strategy of chemotherapy were not considered in the MS model, and the 5-year time horizon for having a child might not be suitable for all patients in the fertility model.

WIDER IMPLICATIONS OF THE FINDINGS

When considering the economic burden of cancer survivors, the results of this study provide an evidence-based reference for clinical decision-making, showing that it is worthwhile to employ GnRHa during chemotherapy to prevent MS and preserve fertility.

STUDY FUNDING/COMPETING INTEREST(S)

This work was supported by the Natural Science Foundation of Fujian Province [2021J02038]; and the Startup Fund for Scientific Research, Fujian Medical University [2021QH1059]. All authors declare no conflict of interest.

TRIAL REGISTRATION NUMBER

N/A.

Low bone mineral density is associated with breast cancer in postmenopausal women: a case-control study

OBJECTIVE

To evaluate risk factors for low bone mineral density (BMD) in postmenopausal breast cancer survivors compared with postmenopausal women without breast cancer (controls).

METHOD

In this study, 112 breast cancer survivors were compared to 224 women (controls). Inclusion criteria were amenorrhea ≥12 months, age 45-75 years, treated for breast cancer, and metastasis-free for at least 5 years. The control group consisted of women without breast cancer, matched by age and menopause status (in a proportion of 1: 2 as sample calculation). The risk factors for low BMD (osteopenia/osteoporosis) were assessed by interview. BMD was measured by dual-energy X-ray absorptiometry in the lumbar spine (L1-L4) and femoral neck. Logistic regression models (odds ratio, OR) were used to identify factors associated with low BMD.

RESULTS

The mean (standard deviation) age of breast cancer survivors was 61.3 (9.7) years, with a mean follow-up of 10.2 (3.9) years. These women had a higher incidence of osteopenia (45.1%) and osteoporosis (22.3%) in the femoral neck than controls (39.3% and 9.0%, respectively) (p = 0.0005). Lumbar spine BMD did not differ between groups (p = 0.332). Univariate analysis adjusted for age and time since menopause revealed that chemotherapy (OR 6.90; 95% confidence interval (CI) 5.57-9.77) was associated with a higher risk of low BMD. Contrarily, regular physical exercise (OR 0.24; 95% CI 0.06-0.98) and a body mass index ≥30 kg/m² (OR 0.09; 95% CI 0.02-0.37) reduced the risk among breast cancer survivors.

CONCLUSION

Postmenopausal breast cancer survivors had a higher incidence of osteopenia and osteoporosis in the femoral neck than women without breast cancer. A history of chemotherapy was a risk factor for low BMD, whereas regular physical activity and high body mass index reduced the risk among breast cancer survivors.

Effect of neoadjuvant chemotherapy on the serum levels of bone turnover markers in women with early-stage breast cancer

Background

To evaluate effects of neoadjuvant chemotherapy on the bone turnover markers of preoperational breast cancer patients.

Methods

Forty-one breast cancer patients (29 premenopausal and 12 postmenopausal) and 60 healthy women (30 premenopausal and 30 postmenopausal) aged 30-64 years, were evaluated for their bone status. Serum levels of the bone formation markers PINP and BAP, as well as the resorption markers ICTP and β-Crosslaps in addition to E2, FSH, 25(OH)D and PTH were measured at the initial diagnosis and at 24 hours after each four chemotherapy cycles. BMD T-scores were determined in 12 patients 6 months after the neoadjuvant chemotherapies.

Results

The baseline levels of both bone formation and resorption markers in premenopausal patients were higher than in premenopausal healthy women (p<0.05), while no statistic difference was observed between postmenopausal patients and postmenopausal healthy women. Regardless of the menopausal status, chemotherapy increased the ICTP and β-Crosslaps levels (p<0.05), but decreased the BAP and PINP levels (p<0.05), the later one significantly more with Taxane medication (p<0.01, p<0.05). Chemotherapy caused significant decreases of 25(OH)D levels in premenopausal (p<0.01) and postmenopausal (p<0.05) patients, however, did not affect the PTH concentrations. In premenopausal patients the E2 level decreased, while the FSH level increased after chemotherapy (p<0.05). Patients with pronounced ICTP and β-Crosslaps combined with reduced BAP and PINP serum concentrations after neoadjuvant chemotherapies were prone to develop osteoporosis 6 month later.

Conclusions

Neoadjuvant chemotherapy appeared to promote bone resorption and inhibit bone formation in both postmenopausal and premenopausal early-stage breast patients.

Low bone density in breast cancer survivors in Korea: prevalence, risk factors and associations with health-related quality of life

PURPOSE

To examine the prevalence and risk factors of low bone density and identify associations with health-related quality of life (HRQOL) in breast cancer survivors in Korea.

METHODS

This study was a cross-sectional descriptive study design. A total of 136 women with breast cancer who had completed their therapy were recruited at one university-based cancer center in Korea. Bone mineral density (BMD), health behaviors (physical activity, diet/nutrition behaviors, smoking, alcohol consumption, sunlight exposure), and HRQOL were measured.

RESULTS

Among the 136 breast cancer survivors, 49 women (36.0%) had osteopenia and six women (4.4%) had osteoporosis. Univariate analyses revealed that older age, low education level, low monthly income, tamoxifen therapy, aromatase inhibitor therapy, calcium supplement intake, and past or current smoking were associated with low bone density (BMD T-score < -1.0). In multivariate analyses, low economic status (OR = 2.22, p = 0.050) and past or current smoking (OR = 3.77, p = 0.039) were final risk factors of low bone density. In addition, women who had low bone density reported worse role function (p = 0.022) than women who did not.

CONCLUSIONS

Women of lower economic status or who are past or current smokers warrant monitoring and treatment strategies to reduce bone loss risk. Nurses may play a crucial role in screening this high-risk group for low bone density and in educating patients on the importance of healthy lifestyle changes.

Low Bone Mineral Density in Middle-Aged Breast Cancer Survivors: Prevalence and Associated Factors

BACKGROUND: The aim of this study was to investigate the prevalence of low bone mineral density (BMD) and associated factors in middle-aged breast cancer survivors (BCS). PATIENTS AND METHODS: A cross-sectional study was conducted with 70 BCS of 45-65 years of age undergoing complete oncology treatment. Logistic regression models were used to identify factors associated with low BMD (osteopenia and osteoporosis taken together as a single group). RESULTS: The mean age of participants was 53.2 ± 5.9 years. BMD was low at the femoral neck in 28.6% of patients and at the lumbar spine in 45.7%. Body mass index ≤ 30 kg/m(2) (adjusted odds ratio (OR) 3.43; 95% confidence interval (CI) 1.0-11.3) and postmenopausal status (OR adjusted 20.42; 95% CI 2.0-201.2) were associated with low BMD at the lumbar spine. Femoral neck measurements, age > 50 years (OR 3.41; 95% CI 1.0-11.6), and time since diagnosis > 50 months (OR adjusted 3.34; 95% CI 1.0-11.3) increased the likelihood of low BMD. CONCLUSION: These findings show that low BMD is common in middle-aged BCS. Factors were identified that may affect BMD in BCS and should be considered when implementing strategies to minimize bone loss in middle-aged women with breast cancer.

Weight management and its role in breast cancer rehabilitation

Overweight and obesity are risk factors for postmenopausal breast cancer, and many women diagnosed with breast cancer, irrespective of menopausal status, gain weight after diagnosis. Weight management plays an important role in rehabilitation and recovery because obesity and/or weight gain may lead to poorer breast cancer prognosis, as well as prevalent comorbid conditions (eg, cardiovascular disease and diabetes), poorer surgical outcomes (eg, increased operating and recovery times, higher infection rates, and poorer healing), lymphedema, fatigue, functional decline, and poorer health and overall quality of life. Health care professionals should encourage weight management at all phases of the cancer care continuum as a means to potentially avoid adverse sequelae and late effects, as well as to improve overall health and possibly survival. Comprehensive approaches that involve dietary and behavior modification, and increased aerobic and strength training exercise have shown promise in either preventing weight gain or promoting weight loss, reducing biomarkers associated with inflammation and comorbidity, and improving lifestyle behaviors, functional status, and quality of life in this high-risk patient population.

Effect of baseline serum vitamin D levels on aromatase inhibitors induced musculoskeletal symptoms: results from the IBIS-II, chemoprevention study using anastrozole

Severe deficiency of vitamin D in adults can cause musculoskeletal pain, stiffness, and joint discomfort. Musculoskeletal symptoms similar to those associated with vitamin D deficiency are frequently seen in breast cancer patients receiving adjuvant aromatase inhibitors (AIs). This is presumably due to oestrogen deficiency caused by AIs. However, no data are available on serum levels of vitamin D and their relation to developing musculoskeletal symptoms/arthralgia in women receiving an AI. IBIS-II is a multicentre randomized placebo controlled trial of the AI, anastrozole, in postmenopausal women aged 40-70 years, who are at increased risk of breast cancer. Serum vitamin D levels were measured for 416 participants. The samples were sent for assays in three batches: the first two batches (n = 250) included paired serum samples and the third batch (n = 166) included paired samples and samples from women who had arthralgia within the first year of follow-up. At entry, 56 (13%) women had adequate (≥ 30 ng/ml), 173 (41%) had inadequate (≥ 20-< 30 ng/mL), 167 (40%) were deficient (> 10-< 20 ng/mL), and 24 (6%) were severely deficient (< 10 ng/mL). At the time of analysis, 225 out of 834 (27%) women had reported arthralgia within the first year of follow-up. Baseline serum vitamin D levels did not significantly predict arthralgia within the first year of follow-up either in the overall group (OR 0.87 (95% CI: 0.67, 1.13; P = 0.30) or separately in the anastrozole (P = 0.60) or placebo groups (P = 0.38). Absolute serum levels of vitamin D increased significantly at one year in the anastrozole group (2.88 ng/ml, [1.71, 4.06; P < 0.0001]) but not in the placebo group (0.75 ng/ml [-0.35, 1.85; P = 0.18]). Only a small and a nonsignificant effect of baseline vitamin D levels were seen on the risk of musculoskeletal symptoms. This does not appear to be a major determinant of risk for these symptoms.

The effect of weight training on bone mineral density and bone turnover in postmenopausal breast cancer survivors with bone loss: a 24-month randomized controlled trial

SUMMARY

This study examined whether 24 months of weight training exercises enhanced the effectiveness of risedronate, calcium, and vitamin D in maintaining or improving bone mineral density (BMD) in 223 postmenopausal breast cancer survivors. Subjects who were > or =50% adherent to exercise had no improvement in BMD but were less likely to lose BMD.

INTRODUCTION

This study examined whether (1) postmenopausal breast cancer survivors (BCS) with bone loss taking 24 months of risedronate, calcium, and vitamin D had increased bone mineral density (BMD) at the total hip, femoral neck, L1-L4 spine, total radius and 33% radius, and decreased bone turnover; (2) subjects who also participated in strength/weight training (ST) exercises had greater increases in BMD and greater decreases in bone turnover; and (3) subjects who also exercised were more likely to preserve (at least maintain) BMD.

METHODS

Postmenopausal BCS (223) were randomly assigned to exercise plus medication or medication only groups. Both groups received 24 months of 1,200 mg of calcium and 400 IU of vitamin D daily and 35 mg of risedronate weekly, and the exercise group additionally had ST exercises twice weekly.

RESULTS

After 24 months, women who took medications without exercising had significant improvements in BMD at the total hip (+1.81%) and spine (+2.85%) and significant decreases in Alkphase B (-8.7%) and serum NTx (-16.7%). Women who also exercised had additional increases in BMD at the femoral neck (+0.29%), total hip (+0.34%), spine (+0.23%), total radius (+0.30%), and additional decreases in Alkphase B (-2.4%) and Serum NTx (-6.5%). Additional changes in BMD and bone turnover with exercise were not significant. Subjects who were > or =50% adherent to exercise were less likely to lose BMD at the total hip (chi-square [1] = 4.66, p = 0.03) and femoral neck (chi-square [1] = 4.63, p = 0.03).

CONCLUSION

Strength/weight training exercises may prevent loss of BMD in postmenopausal BCS at risk for bone loss.

Pharmacology and clinical applications of selective estrogen receptor modulators

Compounds that can be described as selective estrogen receptor modulators (SERMs) have expanded dramatically over the past two decades. The ability of SERMs to act as estrogens in certain tissues while remaining inert or acting as an anti-estrogen in other tissues has opened up opportunities for treating specific estrogen-modulated diseases without accepting the risk of systemic estrogen activity. SERM development has resulted in significant therapeutic advances for breast cancer, osteoporosis and potentially other diseases associated with the menopause. After the publication of the Women's Health Initiative, interest in compound selectivity that reduces menopausal symptoms while protecting bone, breast, uterus and the heart has increased. Future SERMs may also have a therapeutic profile that can be tailored to specific patient populations, including men. This review paper summarizes the characteristics of different SERMs from various pharmacological categories and the feasibility and scope of their use for a large range of disease/health conditions.

Urinary lead exposure and breast cancer risk in a population-based case-control study

BACKGROUND

Lead is a toxic nonessential metal with widespread exposure starting in utero. Lead has been reclassified in 2004 by the International Agency for Research on Cancer Working Group from a "possible" to a "probable" human carcinogen. Lead may be a facilitative or permissive carcinogen, which means that lead may permit or augment the genotoxic effects of other exposures.

METHODS

This population-based study in Wisconsin gathered survey data and home-collected urine specimens from 246 women, ages 20 to 69 years, with incident invasive breast cancer identified from the Wisconsin state registry and 254 age-matched control subjects from population lists from September 2004 to February 2005. We measured urinary lead concentrations by inductively coupled plasma mass spectrometry, adjusted the values by specific gravity, and conducted interviews by telephone to obtain information on known and suspected breast cancer risk factors.

RESULTS

Women in the highest quartile of specific gravity-adjusted lead level (>/=1.10 mug/L) had twice the breast cancer risk of those in the lowest quartile (<0.42 mug/L; odds ratio, 1.99; 95% confidence interval, 1.1-3.6) after adjustment for established risk factors. Excluding women who were currently taking nonsteroidal aromatase inhibitors (n = 52), we did not observe any increased breast cancer risk after adjustment for established risk factors.

CONCLUSION

Our population-based case-control study suggests that lead exposure, as determined by specific gravity-adjusted urinary lead concentrations, is not associated with a significant increased risk for breast cancer.