Repeat bone mineral density screening and prediction of hip and major osteoporotic fracture

Modelling future bone mineral density: Simplicity or complexity?

BACKGROUND

Osteoporotic fractures are a major global public health issue, leading to patient suffering and death, and considerable healthcare costs. Bone mineral density (BMD) measurement is important to identify those with osteoporosis and assess their risk of fracture. Both the absolute BMD and the change in BMD over time contribute to fracture risk. Predicting future fracture in individual patients is challenging and impacts clinical decisions such as when to intervene or repeat BMD measurement. Although the importance of BMD change is recognised, an effective way to incorporate this marginal effect into clinical algorithms is lacking.

METHODS

We compared two methods using longitudinal DXA data generated from subjects with two or more hip DXA scans on the same machine between 2000 and 2018. A simpler statistical method (ZBM) was used to predict an individual's future BMD based on the mean BMD and the standard deviation of the reference group and their BMD measured in the latest scan. A more complex deep learning (DL)-based method was developed to cope with multidimensional longitudinal data, variables extracted from patients' historical DXA scan(s), as well as features drawn from the ZBM method. Sensitivity analyses of several subgroups was conducted to evaluate the performance of the derived models.

RESULTS

2948 white adults aged 40-90 years met our study inclusion: 2652 (90 %) females and 296 (10 %) males. Our DL-based models performed significantly better than the ZBM models in women, particularly our Hybrid-DL model. In contrast, the ZBM-based models performed as well or better than DL-based models in men.

CONCLUSIONS

Deep learning-based and statistical models have potential to forecast future BMD using longitudinal clinical data. These methods have the potential to augment clinical decisions regarding when to repeat BMD testing in the assessment of osteoporosis.

Metabolic Bone Disease

Metabolic bone diseases encompass a group of disorders characterized by abnormalities in bone metabolism, structure, or mineralization. These disorders negatively impact overall health and quality of life and place individuals at high risk for fracture, which may increase morbidity and mortality. Clinicians should understand who is at risk for these disorders, select individuals who warrant further workup, determine appropriate laboratory and imaging evaluation, interpret results in a clinical context, and choose an optimal management strategy based on the individual patient.

Validity of Major Osteoporotic Fracture Diagnoses in the Danish National Patient Registry

Objective

To evaluate the validity of diagnosis codes for Major Osteoporotic Fracture (MOF) in the Danish National Patient Registry (NPR) and secondly to evaluate whether the fracture was incident/acute using register-based definitions including date criteria and procedural codes.

Methods

We identified a random sample of 2400 records with a diagnosis code for a MOF in the NPR with dates in the year of 2018. Diagnoses were coded with the 10th revision of the International Classification of Diseases (ICD-10). The sample included 2375 unique fracture patients from the Region of Southern Denmark. Medical records were retrieved for the study population and reviewed by an algorithmic search function and medical doctors to verify the MOF diagnoses. Register-based definitions of incident/acute MOF was evaluated in NPR data by applying date criteria and procedural codes.

Results

The PPV for MOF diagnoses overall was 0.99 (95% CI: 0.98;0.99) and PPV=0.99 for the four individual fracture sites, respectively. Further, analyses of incident/acute fractures applying date criteria, procedural codes and using patients' first contact in the NPR resulted in PPV=0.88 (95% CI: 0.84;0.91) for hip fractures, PPV=0.78 (95% CI: 0.74;0.83) for humerus fractures, PPV=0.78 (95% CI: 0.73;0.83) for clinical vertebral fractures and PPV=0.87 (95% CI: 0.83;0.90) for wrist fractures.

Conclusion

ICD-10 coded MOF diagnoses are valid in the NPR. Furthermore, a set of register-based criteria can be applied to qualify if the MOF fracture was incident/acute. Thus, the NPR is a valuable and reliable data source for epidemiological research on osteoporotic fractures.

Dual-energy computed tomography and micro-computed tomography for assessing bone regeneration in a rabbit tibia model

To gain a more meaningful understanding of bone regeneration, it is essential to select an appropriate assessment method. Micro-computed tomography (Micro-CT) is widely used for bone regeneration because it provides a substantially higher spatial resolution. Dual-energy computed tomography (DECT) ensure shorter scan time and lower radiation doses during quantitative evaluation. Therefore, in this study, DECT and Micro-CT were used to evaluate bone regeneration. We created 18 defects in the tibial plateau of the rabbits and filled them with porous polyetheretherketone implants to promote bone regeneration. At 4, 8, and 12 weeks, Micro-CT and DECT were used to assess the bone repair in the defect region. In comparison to Micro-CT (152 ± 54 mg/cm3), the calcium density values and hydroxyapatite density values obtained by DECT [DECT(Ca) and DECT(HAP)] consistently achieved lower values (59 ± 25 mg/cm3, 126 ± 53 mg/cm3). In addition, there was a good association between DECT and Micro-CT (R = 0.98; R2 = 0.96; DECT(Ca): y = 0.45x-8.31; DECT(HAP): y = 0.95x-17.60). This study highlights the need to use two different imaging methods, each with its advantages and disadvantages, to better understand the bone regeneration process.

Follow-up Bone Mineral Density Testing: 2023 Official Positions of the International Society for Clinical Densitometry

Dual-energy X-ray absorptiometry (DXA) is the gold standard method for measuring bone mineral density (BMD) which is most strongly associated with fracture risk. BMD is therefore the basis for the World Health Organization's densitometric definition of osteoporosis. The International Society for Clinical Densitometry (ISCD) promotes best densitometry practices and its official positions reflect critical review of current evidence by domain experts. This document reports new official positions regarding follow-up DXA examinations based on a systematic review of literature published through December 2022. Adoption of official positions requires consensus agreement from an expert panel following a modified RAND protocol. Unless explicitly altered by the new position statements, prior ISCD official positions remain in force. This update reflects increased consideration of the clinical context prompting repeat examination. Follow-up DXA should be performed with pre-defined objectives when the results would have an impact on patient management. Testing intervals should be individualized according to the patient's age, sex, fracture risk and treatment history. Incident fractures and therapeutic approach are key considerations. Appropriately ordered and interpreted follow-up DXA examinations support diagnostic and therapeutic decision making, thereby contributing to excellent clinical care. Future research should address the complementary roles of clinical findings, imaging and laboratory testing to guide management.

Bone health is improving over time: data from Framingham cohorts

Hip fractures have steadily declined in the USA. We found that bone health, as measured by bone mineral density, has significantly improved over the past 30 years. Our findings contradict previous studies and offer one explanation for the decline in hip fractures.

PURPOSE

Despite the widespread undertreatment of osteoporosis, hip fractures have been declining in the USA. The reasons for this decline are unclear; however, one possible explanation could be that the bone health has improved over time.

METHODS

To determine the trends in bone density in the USA, we analyzed the bone mineral density scans of 7216 subjects across three generations in the Framingham Heart Study. We compared the mean femoral bone mineral density (BMD) between cohorts then constructed a linear regression model controlling for age, sex, BMI, and smoking rates.

RESULTS

We observed that the mean BMD of each successive Framingham cohort increased (p < 0.001). After controlling for age, subjects born later had higher BMD. The results from the linear-regression model developed on the original cohort indicated that the BMD of the women from the offspring and third generation were higher than what would be predicted. Younger generations demonstrated higher activity scores (p < 0.001), and lower smoking rates (p = 0.045).

CONCLUSION

These data suggest that bone health, measured by bone mineral density scans, is improving in later generations, in part due to decreased smoking rates and higher rates of activity.

Recommendations on screening for primary prevention of fragility fractures

BACKGROUND

Fragility fractures are a major health concern for older adults and can result in disability, admission to hospital and long-term care, and reduced quality of life. This Canadian Task Force on Preventive Health Care (task force) guideline provides evidence-based recommendations on screening to prevent fragility fractures in community-dwelling individuals aged 40 years and older who are not currently on preventive pharmacotherapy.

METHODS

We commissioned systematic reviews on benefits and harms of screening, predictive accuracy of risk assessment tools, patient acceptability and benefits of treatment. We analyzed treatment harms via a rapid overview of reviews. We further examined patient values and preferences via focus groups and engaged stakeholders at key points throughout the project. We used the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach to determine the certainty of evidence for each outcome and strength of recommendations, and adhered to Appraisal of Guidelines for Research and Evaluation (AGREE), Guidelines International Network and Guidance for Reporting Involvement of Patients and the Public (GRIPP-2) reporting guidance.

RECOMMENDATIONS

We recommend "risk assessment-first" screening for prevention of fragility fractures in females aged 65 years and older, with initial application of the Canadian clinical Fracture Risk Assessment Tool (FRAX) without bone mineral density (BMD). The FRAX result should be used to facilitate shared decision-making about the possible benefits and harms of preventive pharmacotherapy. After this discussion, if preventive pharmacotherapy is being considered, clinicians should request BMD measurement using dual-energy x-ray absorptiometry (DXA) of the femoral neck, and re-estimate fracture risk by adding the BMD T-score into FRAX (conditional recommendation, low-certainty evidence). We recommend against screening females aged 40-64 years and males aged 40 years and older (strong recommendation, very low-certainty evidence). These recommendations apply to community-dwelling individuals who are not currently on pharmacotherapy to prevent fragility fractures.

INTERPRETATION

Risk assessment-first screening for females aged 65 years and older facilitates shared decision-making and allows patients to consider preventive pharmacotherapy within their individual risk context (before BMD). Recommendations against screening males and younger females emphasize the importance of good clinical practice, where clinicians are alert to changes in health that may indicate the patient has experienced or is at higher risk of fragility fracture.

Prediction of osteoporosis using radiomics analysis derived from single source dual energy CT

BACKGROUND

With the aging population of society, the incidence rate of osteoporosis is increasing year by year. Early diagnosis of osteoporosis plays a significant role in the progress of disease prevention. As newly developed technology, computed tomography (CT) radiomics could discover radiomic features difficult to recognize visually, providing convenient, comprehensive and accurate osteoporosis diagnosis. This study aimed to develop and validate a clinical-radiomics model based on the monochromatic imaging of single source dual-energy CT for osteoporosis prediction.

METHODS

One hundred sixty-four participants who underwent both single source dual-energy CT and quantitative computed tomography (QCT) lumbar-spine examination were enrolled in a study cohort including training datasets (n = 114 [30 osteoporosis and 84 non-osteoporosis]) and validation datasets (n = 50 [12 osteoporosis and 38 non-osteoporosis]). One hundred seven radiomics features were extracted from 70-keV monochromatic CT images. With QCT as the reference standard, a radiomics signature was built by using least absolute shrinkage and selection operator (LASSO) regression on the basis of reproducible features. A clinical-radiomics model was constructed by incorporating the radiomics signature and a significant clinical predictor (age) using multivariate logistic regression analysis. Model performance was assessed by its calibration, discrimination and clinical usefulness.

RESULTS

The radiomics signature comprised 14 selected features and showed good calibration and discrimination in both training and validation cohorts. The clinical-radiomics model, which incorporated the radiomics signature and a significant clinical predictor (age), also showed good discrimination, with an area under the receiver operating characteristic curve (AUC) of 0.938 (95% confidence interval, 0.903-0.952) in the training cohort and an AUC of 0.988 (95% confidence interval, 0.967-0.998) in the validation cohort, and good calibration. The clinical-radiomics model stratified participants into groups with osteoporosis and non-osteoporosis with an accuracy of 94.0% in the validation cohort. Decision curve analysis (DCA) demonstrated that the radiomics signature and the clinical-radiomics model were clinically useful.

CONCLUSIONS

The clinical-radiomics model incorporating the radiomics signature and a clinical parameter had a good ability to predict osteoporosis based on dual-energy CT monoenergetic imaging.

Application of intelligent X-ray image analysis in risk assessment of osteoporotic fracture of femoral neck in the elderly

The paper focuses on establishing a risk assessment model of femoral neck osteoporotic fracture (FNOF) in the elderly population and improving the screening efficiency and accuracy of such diseases in specific populations. In literature research, the main risk factors of femoral neck osteoporosis (FNOP) in the elderly were studied and analyzed; the femur region of interest (ROI) and the hard bone edge segmentation model were selected from the X-ray digital image by using the image depth learning method. On this basis, the femoral trabecular score and femoral neck strength (FNS) in the set region were selected as the main evaluation elements, and the quantitative analysis method was established; an X-ray image processing method was applied to the feasibility study of FNOP and compared with dual-energy X-ray absorptiometry measurements of bone mineral density; Finally, the main risk factors of FNOP were selected and the prediction model of FNOP in the elderly population was established based on medical image processing, machine learning model construction and other methods. Some FNOP health records were selected as test samples for comparative analysis with traditional manual evaluation methods. The paper shows the risk assessment model of FNOF in the elderly population, which is feasible in testing. Among them, the artificial neural network model had a better accuracy (95.83%) and recall rate (100.00%), and the support vector machine prediction model had high specificity (62.50%). With the help of a machine learning method to establish the risk assessment model of FNOF for the elderly, one can provide decision support for the fracture risk assessment of the elderly and remind the clinic to give targeted interventions for the above high-risk groups in order to reduce the fracture risk.

EXTENSIVE EXPERTISE IN ENDOCRINOLOGY: Osteoporosis management

Fractures occur in about half of older White women, and almost a third of older White men. However, 80% of the older individuals who have fractures do not meet the bone density definition of osteoporosis, suggesting that this definition is not an appropriate threshold for offering treatment. Fracture risk can be estimated based on clinical risk factors with or without bone density. A combination of calculated risk, fracture history, and bone density is used in treatment decisions. Medications available for reducing fracture risk act either to inhibit bone resorption or to promote bone formation. Romosozumab is unique in that it has both activities. Bisphosphonates are the most widely used interventions because of their efficacy, safety, and low cost. Continuous use of oral bisphosphonates for >5 years increases the risk of atypical femoral fractures, so is usually punctuated with drug holidays of 6-24 months. Denosumab is a further potent anti-resorptive agent given as 6-monthly s.c. injections. It is comparable to the bisphosphonates in efficacy and safety but has a rapid offset of effect after discontinuation so must be followed by an alternative drug, usually a bisphosphonate. Teriparatide stimulates both bone formation and resorption, substantially increases spine density, and reduces vertebral and non-vertebral fracture rates, though data for hip fractures are scant. Treatment is usually limited to 18-24 months, followed by the transition to an anti-resorptive. Romosozumab is given as monthly s.c. injections for 1 year, followed by an anti-resorptive. This sequence prevents more fractures than anti-resorptive therapy alone. Because of cost, anabolic drugs are usually reserved for those at very high fracture risk. 25-hydroxyvitamin D levels should be maintained above 30 nmol/L, using supplements if sunlight exposure is limited. Calcium intake has little effect on bone density and fracture risk but should be maintained above 500 mg/day using dietary sources.

Update of the fracture risk prediction tool FRAX: a systematic review of potential cohorts and analysis plan

We describe the collection of cohorts together with the analysis plan for an update of the fracture risk prediction tool FRAX with respect to current and novel risk factors. The resource comprises 2,138,428 participants with a follow-up of approximately 20 million person-years and 116,117 documented incident major osteoporotic fractures.

INTRODUCTION

The availability of the fracture risk assessment tool FRAX® has substantially enhanced the targeting of treatment to those at high risk of fracture with FRAX now incorporated into more than 100 clinical osteoporosis guidelines worldwide. The aim of this study is to determine whether the current algorithms can be further optimised with respect to current and novel risk factors.

METHODS

A computerised literature search was performed in PubMed from inception until May 17, 2019, to identify eligible cohorts for updating the FRAX coefficients. Additionally, we searched the abstracts of conference proceedings of the American Society for Bone and Mineral Research, European Calcified Tissue Society and World Congress of Osteoporosis. Prospective cohort studies with data on baseline clinical risk factors and incident fractures were eligible.

RESULTS

Of the 836 records retrieved, 53 were selected for full-text assessment after screening on title and abstract. Twelve cohorts were deemed eligible and of these, 4 novel cohorts were identified. These cohorts, together with 60 previously identified cohorts, will provide the resource for constructing an updated version of FRAX comprising 2,138,428 participants with a follow-up of approximately 20 million person-years and 116,117 documented incident major osteoporotic fractures. For each known and candidate risk factor, multivariate hazard functions for hip fracture, major osteoporotic fracture and death will be tested using extended Poisson regression. Sex- and/or ethnicity-specific differences in the weights of the risk factors will be investigated. After meta-analyses of the cohort-specific beta coefficients for each risk factor, models comprising 10-year probability of hip and major osteoporotic fracture, with or without femoral neck bone mineral density, will be computed.

CONCLUSIONS

These assembled cohorts and described models will provide the framework for an updated FRAX tool enabling enhanced assessment of fracture risk (PROSPERO (CRD42021227266)).

Repeat Bone Mineral Density Screening Measurement and Fracture Prediction in Older Men: A Prospective Cohort Study

CONTEXT

Whether repeated bone mineral density (BMD) screening improves fracture prediction in men is uncertain.

OBJECTIVE

We evaluated whether a second BMD 7 years after the initial BMD improves fracture prediction in older men.

METHODS

Among 3651 community-dwelling men (mean age 79.1 years) with total hip BMD at baseline and Year 7 (Y7), self-reported fractures after Y7 were confirmed by radiographic reports. Fracture prediction assessed using Cox proportional hazards regression and logistic regression with receiver operating characteristic curves for models based on initial BMD, BMD change, and the combination of initial BMD and BMD change (combination model).

RESULTS

During an average follow-up of 8.2 years after Y7, 793 men experienced ≥ 1 clinical fractures, including 426 men with major osteoporotic fractures (MOF) and 193 men with hip fractures. Both initial BMD and BMD change were associated with risk of fracture outcomes independent of each other, but the association was stronger for initial BMD. For example, the multivariable hazard ratio of MOF in the combination model per 1 SD decrement in BMD was 1.76 (95% CI 1.57-1.98) for initial BMD and 1.19 (95% CI 1.08-1.32) for BMD change. Discrimination of fracture outcomes with initial BMD models was somewhat better than with BMD change models and similar to combination models (AUC value for MOF 0.68 [95% CI 0.66-0.71] for initial BMD model, 0.63 [95% CI 0.61-0.66] for BMD change model, and 0.69 [95% CI 0.66-0.71] for combination model).

CONCLUSION

Repeating BMD after 7 years did not meaningfully improve fracture prediction at the population level in community-dwelling older men.

Bone Mineral Density Screening Interval and Transition to Osteoporosis in Asian Women

BACKGRUOUND

Bone mineral density (BMD) testing is indicated for women aged 65 years, but screening strategies for osteoporosis are controversial. Currently, there is no study focusing on the BMD testing interval in Asian populations. The current study aimed to evaluate the estimated time interval for screening osteoporosis.

METHODS

We conducted a study of 6,385 subjects aged 50 years and older who underwent dual-energy X-ray absorptiometry screening more than twice at Samsung Medical Center as participants in a routine health checkup. Subjects were divided based on baseline T-score into mild osteopenia (T-score, <-1.0 to >-1.5), moderate osteopenia (T-score, ≤-1.5 to >-2.0), and severe osteopenia (T-score, ≤-2.0 to >-2.5). Information about personal medical and social history was collected by a structured questionnaire.

RESULTS

The adjusted estimated BMD testing interval for 10% of the subjects to develop osteoporosis was 13.2 years in mild osteopenia, 5.0 years in moderate osteopenia, and 1.5 years in severe osteopenia.

CONCLUSION

Our study provides extended information about BMD screening intervals in Asian female population. Baseline T-score was important for predicting BMD screening interval, and repeat BMD testing within 5 years might not be necessary in mild osteopenia subjects.

Race and Age Impact Osteoporosis Screening Rates in Women Prior to Hip Fracture

Bone mineral density screening and clinical risk factors are important to stratify individuals for increased risk of fracture. In a population with no history of fractures or baseline bone density measurement, black women were less likely to be screened than white counterparts prior to hip fracture.

PURPOSE

To evaluate overall BMD (bone mineral density) screening rates within two years of hip fracture and to identify any disparities for osteoporosis screening or treatment in a female cohort who were eligible for screening under insurance and national recommendations.

METHODS

Data were obtained from 1,109 female patients listed in the Research Action for Health Network (REACHnet) database, which consists of multiple health partner systems in Louisiana and Texas. Patients < 65 years old or with a history of hip fracture or osteoporosis diagnosis, screening or treatment more than 2 years before hip fracture were removed.

RESULTS

Only 223 (20.1%) females were screened within the two years prior to hip fracture. Additionally, only 23 (10%) of the screened patients received treatment, despite 187 (86.6%) patients being diagnosed with osteoporosis or osteopenia. Screening rates reached a maximum of 27.9% in the 75-80 age group, while the 90 + age group had the lowest screening rates of 12%. We found a quadratic relationship between age and screening rates, indicating that the screening rate increases in age until age 72 and then decreases starkly. After adjusting for potential confounders, we found that black patients had significantly decreased screening rates compared to white patients (adjusted OR = .454, 95% CI = .227-.908, p value = .026) which held in general and for patient ages 65-97.

CONCLUSION

Despite national recommendations, overall BMD screening rates among women prior to hip fracture are low. If individuals are not initially screened when eligible, they are less likely to ever be screened prior to fracture. Clinicians should address racial disparities by recommending more screening to otherwise healthy black patients above the age of 65. Lastly, treatment rates need to increase among those diagnosed with osteoporosis since all patients went on to hip fracture.

Declining serum bone turnover markers are associated with the short-term positive change of lumbar spine bone mineral density in postmenopausal women

OBJECTIVE

While serum bone turnover markers (BTMs) and bone mineral density (BMD) have been confirmed as useable risk assessment tools for postmenopausal osteoporosis, the associations between BTMs and BMD changes are still ambiguous. The aim of this study was to explore the underlying associations between BTMs and BMD changes in postmenopausal women.

METHODS

Between January 2015 and October 2020, 135 postmenopausal women were retrospectively enrolled. They were divided into two groups according to lumbar spine (LS) 1-4 BMD change (1 y T-score minus baseline T-score, Group 1 [n = 36] < 0 and Group 2 [n = 99] ≥ 0). The changes of BTMs (N-terminal middle segment osteocalcin [N-MID], propeptide of type I procollagen [P1NP], and β-C-terminal telopeptide of type I collagen [β-CTX]) and their associations with LS 1-4 BMD change were analyzed. The biochemical indices and clinical parameters related with LS 1-4 BMD change were also evaluated.

RESULTS

The 1 year N-MID, P1NP, β-CTX and Phosphorus in Group 2 were lower than those in Group 1 (P < 0.05), their changes within 1 year were significantly negatively correlated with LS 1-4 BMD change (R2 = -0.200, P < 0.001; R2 = -0.230, P < 0.001; R2 = -0.186, P < 0.001; R2 = -0.044, P = 0.015; respectively). Except for the Phosphorus change (area under the curve [AUC] = 0.623), the changes of N-MID, P1NP, and β-CTX and their 1 year levels had similar AUC to diagnose the short-term LS 1-4 BMD change (AUC > 0.7 for all, with the AUC of 1 y P1NP being the largest at 0.803). Binary logistic regression analysis showed that the physical activity and drug intervention were the determinant factors for the LS 1-4 BMD change (odds ratio = 6.856, 95% confidence interval: 2.058-22.839, P = 0.002; odds ratio  = 5.114, 95% confidence interval: 1.551-16.864, P = 0.007; respectively).

CONCLUSIONS

Declining N-MID, P1NP, β-CTX, and Phosphorus are associated with the short-term increase of LS 1-4 BMD within 1 year. Physical activity and drug intervention are factors significantly influencing the change of LS 1-4 BMD in postmenopausal women.

Skip that repeat DXA scan in these postmenopausal women

Repeat bone density measurement offers no advantage in predicting fracture risk in postmenopausal women who do not have osteoporosis.

Pharmacogenomic Effects of β-Blocker Use on Femoral Neck Bone Mineral Density

CONTEXT

Recent studies have shown that β-blocker (BB) users have a decreased risk of fracture and higher bone mineral density (BMD) compared to nonusers, likely due to the suppression of adrenergic signaling in osteoblasts, leading to increased BMD. There is also variability in the effect size of BB use on BMD in humans, which may be due to pharmacogenomic effects.

OBJECTIVE

To investigate potential single-nucleotide variations (SNVs) associated with the effect of BB use on femoral neck BMD, we performed a cross-sectional analysis using clinical data, dual-energy x-ray absorptiometry, and genetic data from the Framingham Heart Study's (FHS) Offspring Cohort. We then sought to validate our top 4 genetic findings using data from the Rotterdam Study, the BPROOF Study, the Malta Osteoporosis Fracture Study (MOFS), and the Hertfordshire Cohort Study.

METHODS

We used sex-stratified linear mixed models to determine SNVs that had a significant interaction effect with BB use on femoral neck (FN) BMD across 11 gene regions. We also evaluated the association of our top SNVs from the FHS with microRNA (miRNA) expression in blood and identified potential miRNA-mediated mechanisms by which these SNVs may affect FN BMD.

RESULTS

One variation (rs11124190 in HDAC4) was validated in females using data from the Rotterdam Study, while another (rs12414657 in ADRB1) was validated in females using data from the MOFS. We performed an exploratory meta-analysis of all 5 studies for these variations, which further validated our findings.

CONCLUSION

This analysis provides a starting point for investigating the pharmacogenomic effects of BB use on BMD measures.

Faster Lumbar Spine Bone Loss in Midlife Predicts Subsequent Fracture Independent of Starting Bone Mineral Density

CONTEXT

Bone mineral density (BMD) decreases rapidly during menopause transition (MT), and continues to decline in postmenopause.

OBJECTIVE

This work aims to examine whether faster BMD loss during the combined MT and early postmenopause is associated with incident fracture, independent of starting BMD, before the MT.

METHODS

The Study of Women's Health Across the Nation, a longitudinal cohort study, included 451 women, initially premenopausal or early perimenopausal, and those transitioned to postmenopause. Main outcome measures included time to first fracture after early postmenopause.

RESULTS

In Cox proportional hazards regression, adjusted for age, body mass index, race/ethnicity, study site, use of vitamin D and calcium supplements, and use of bone-detrimental or -beneficial medications, each SD decrement in lumbar spine (LS) BMD before MT was associated with a 78% increment in fracture hazard (P = .007). Each 1% per year faster decline in LS BMD was related to a 56% greater fracture hazard (P = .04). Rate of LS BMD decline predicted future fracture, independent of starting BMD. Women with a starting LS BMD below the sample median, and an LS BMD decline rate faster than the sample median had a 2.7-fold greater fracture hazard (P = .03). At the femoral neck, neither starting BMD nor rate of BMD decline was associated with fracture.

CONCLUSION

At the LS, starting BMD before the MT and rate of decline during the combined MT and early postmenopause are independent risk factors for fracture. Women with a below-median starting LS BMD and a faster-than-median LS BMD decline have the greatest fracture risk.

In vivo quantification of bone mineral density of lumbar vertebrae using fast kVp switching dual-energy CT: correlation with quantitative computed tomography

Background

Osteoporosis is a common, progressive disease related to low bone mineral density (BMD). If it can be diagnosed at an early stage, osteoporosis is treatable. Quantitative computed tomography (QCT) is one of the current reference standards of BMD measurement, but dual-energy computed tomography (DECT) is considered to be a potential alternative. This study aimed to evaluate the feasibility and accuracy of phantomless in vivo DECT-based BMD quantification in comparison with QCT.

Methods

A total of 128 consecutive participants who underwent DECT lumbar examinations between July 2018 and February 2019 were retrospectively analyzed. The density of calcium (water), hydroxyapatite (water), calcium (fat), and hydroxyapatite (fat) [D_Ca(Wa), D_HAP(Wa), D_Ca(Fat) and D_HAP(Fat), respectively] were measured along with BMD in the trabecular bone of lumbar level 1-2 by DECT and QCT. Linear regression analysis was performed to assess the relationship between DECT- and QCT-derived BMD at both the participant level and the vertebral level. Linear regression models were quantitatively evaluated with adjusted R-square, normalized mean squared error (NMSE) and relative error (RE). Bland-Altman analysis was conducted to assess agreement between measurements. P<0.05 was considered statistically significant.

Results

Strong correlations were observed between DECT- and QCT-derived BMD at both the participant level and the vertebral level (adjusted R² =0.983-0.987; NMSE = 1.6-2.1%; RE_linear =0.6-0.9%). Bland-Altman plots indicated high agreement between both measurements. D_Ca(Fat) and D_HAP(Fat) showed relatively similar and optimal predictive capability for QCT-derived BMD (both: adjusted R² =0.987, NMSE =1.6%, RE_linear =0.6%).

Conclusions

Fast kVp switching DECT enabled accurate phantomless in vivo BMD quantification of the lumbar spine. D_Ca(Fat) and D_HAP(Fat) had relatively similar and optimal predictive capability.

miRNA Mechanisms Underlying the Association of Beta Blocker Use and Bone Mineral Density

Osteoporosis is a debilitating and costly disease that causes fractures in 33% of women and 20% of men over the age of 50 years. Recent studies have shown that beta blocker (BB) users have higher bone mineral density (BMD) and decreased risk of fracture compared with non-users. The mechanism underlying this association is thought to be due to suppression of adrenergic signaling in osteoblasts, which leads to increased BMD in rodent models; however, the mechanism in humans is unknown. Also, several miRNAs are associated with adrenergic signaling and BMD in separate studies. To investigate potential miRNA mechanisms, we performed a cross-sectional analysis using clinical data, dual-energy X-ray absorptiometry (DXA) scans, and miRNA and mRNA profiling of whole blood from the Framingham Study's Offspring Cohort. We found nine miRNAs associated with BB use and increased BMD. In parallel network analyses, we discovered a subnetwork associated with BMD and BB use containing two of these nine miRNAs, miR-19a-3p and miR-186-5p. To strengthen this finding, we showed that these two miRNAs had significantly higher expression in individuals without incident fracture compared with those with fracture in an external data set. We also noted a similar trend in association between these miRNA and Z-score as calculated from heel ultrasound measures in two external cohorts (SOS-Hip and SHIP-TREND). Because miR-19a directly targets the ADRB1 mRNA transcript, we propose BB use may downregulate ADRB1 expression in osteoblasts through increased miR-19a-3p expression. We used enrichment analysis of miRNA targets to find potential indirect effects through insulin and parathyroid hormone signaling. This analysis provides a starting point for delineating the role of miRNA on the association between BB use and BMD. © 2020 American Society for Bone and Mineral Research (ASBMR).

Serial Bone Density Measurement and Incident Fracture Risk Discrimination in Postmenopausal Women

IMPORTANCE

Repeated bone mineral density (BMD) testing to screen for osteoporosis requires resources. For patient counseling and optimal resource use, it is important for clinicians to know whether repeated BMD measurement (compared with baseline BMD measurement alone) improves the ability to discriminate between postmenopausal women who will and will not experience a fracture.

OBJECTIVE

To assess whether a second BMD measurement approximately 3 years after the initial assessment is associated with improved ability to estimate fracture risk beyond the baseline BMD measurement alone.

DESIGN, SETTING, AND PARTICIPANTS

The Women's Health Initiative is a prospective observational study. Participants in the present cohort study included 7419 women with a mean (SD) follow-up of 12.1 (3.4) years between 1993 and 2010 at 3 US clinical centers. Data analysis was conducted between May 2019 and December 2019.

MAIN OUTCOMES AND MEASURES

Incident major osteoporotic fracture (ie, hip, clinical spine, forearm, or shoulder fracture), hip fracture, baseline BMD, and absolute change in BMD were assessed. The area under the receiver operating characteristic curve (AU-ROC) for baseline BMD, absolute change in BMD, and the combination of baseline BMD and change in BMD were calculated to assess incident fracture risk discrimination during follow-up.

RESULTS

Of 7419 participants, the mean (SD) age at baseline was 66.1 (7.2) years, the mean (SD) body mass index was 28.7 (6.0), and 1720 (23%) were nonwhite individuals. During the study follow-up (mean [SD] 9.0 [3.5] years after the second BMD measurement), 139 women (1.9%) experienced hip fractures, and 732 women (9.9%) experienced major osteoporotic fracture. In discriminating between women who experience hip fractures and those who do not, AU-ROC values were 0.71 (95% CI, 0.67-0.75) for baseline total hip BMD, 0.61 (95% CI, 0.56-0.65) for change in total hip BMD, and 0.73 (95% CI, 0.69-0.77) for the combination of baseline total hip BMD and change in total hip BMD. Femoral neck and lumbar spine BMD values had similar discrimination for hip fracture. For discrimination of major osteoporotic fracture, AU-ROC values were 0.61 (95% CI, 0.59-0.63) for baseline total hip BMD, 0.53 (95% CI, 0.51-0.55) for change in total hip BMD, and 0.61 (95% CI, 0.59-0.63) for the combination of baseline total hip BMD and change in total hip BMD. Femoral neck and lumbar spine BMD values had similar ability to discriminate between women who experienced major osteoporotic fracture and those who did not. Associations between change in bone density and fracture risk did not differ by subgroup, including diabetes, age, race/ethnicity, body mass index, or baseline BMD T score.

CONCLUSIONS AND RELEVANCE

The findings of this study suggest that a second BMD assessment approximately 3 years after the initial measurement was not associated with improved discrimination between women who did and did not experience subsequent hip fracture or major osteoporotic fracture beyond the baseline BMD value alone and should not routinely be performed.

Association of Beta Blocker Use With Bone Mineral Density in the Framingham Osteoporosis Study: A Cross-Sectional Study

Some, but not all, prior observational studies have shown that beta blocker (BB) use is associated with lower fracture risk and higher bone mineral density (BMD). Rodent studies show the mechanism to involve the reduction in the effects of beta‐adrenergic signaling on bone remodeling. Because previous studies did not have detailed information on dose, duration, and beta‐1 selectivity, we examined these in a cross‐sectional analysis of the association between BB use and hip and spine BMD using DXA with the Offspring Cohort of the Framingham Heart Study. The sample size was n = 1520, and 397 individuals used BBs. We used propensity score modeling to balance a comprehensive set of covariates using inverse probability of treatment weighting (IPTW) to minimize bias due to treatment indication. We found significant differences in BMD between BB users and non‐users for three of four BMD measurements (femoral neck: 3.1%, 95% CI, 1.1% to 5.0%; total femur: 2.9%, 95% CI, 0.9% to 4.9%; femoral trochanter: 2.4%, 95% CI, −0.1% to 5.0%; and lumbar spine: 2.7%, 95% CI, 0.2% to 5.0%). Results were found to be similar between sexes although the magnitude of association was larger for women. Similar differences were estimated for beta‐1 selective and nonselective BBs compared with no BB use. We modeled dose in categories (no BB use, low‐dose, high‐dose) and as a continuous variable and found an increasing dose response that levels off at higher doses. Finally, associations were similar for short‐term versus long‐term (≤4 years versus >4 years) use. In summary, this large comprehensive study shows that BB use is associated with higher BMD in a dose‐related manner regardless of beta‐1 specificity and duration of use, which supports the conduct of a randomized clinical trial of BBs for achieving improvements in BMD for individuals at risk of bone loss with aging. © 2020 The Authors. JBMR Plus published by Wiley Periodicals LLC. on behalf of American Society for Bone and Mineral Research.

Calcitonin: A useful old friend

Calcitonin regulates blood calcium levels and possesses certain clinically useful anti-fracture properties. Specifically, it reduces vertebral fractures in postmenopausal osteoporotic women significantly compared to a placebo. Nevertheless, the use of calcitonin has declined over the years and salmon calcitonin is no longer the first-line treatment for many of its indications. Commercial calcitonin only exists in intranasal or injectable preparations, which are less preferable for patients. Efficacy of a potential oral formulation has been under investigation but achieving adequate bioavailability remains a conundrum and the latest phase III trials have not shown promising evidence justifying its use. Associations with cancer have also derailed this treatment option. Furthermore, the rise of bisphosphonates and, more recently, monoclonal antibodies (such as denosumab), has revolutionised the treatment of osteoporotic fractures. Therefore, we are posed with an interesting question: is calcitonin a treatment of the past? This review aims to explore the reasons behind this paradigm shift and outline the potential role of calcitonin in the management of fractures and other conditions in the years to come.

Radiographic Emphysema, Circulating Bone Biomarkers, and Progressive Bone Mineral Density Loss in Smokers

RATIONALE

Osteoporosis is common in individuals with chronic obstructive pulmonary disease. Lung-specific factors, including radiographic emphysema, independently associate with low bone mineral density in cross-sectional smoking cohorts. However, factors associated with progressive bone loss in smokers are understudied and largely unknown.

OBJECTIVES

To determine the relationship between radiographic emphysema, circulating bone metabolism markers, and pulmonary function and accelerated bone mineral density loss in smokers.

METHODS

Two hundred and forty male and female current and former smokers, 40 years of age or older, underwent baseline and 2-year assessments of pulmonary function, computed tomography-assessed emphysema, dual X-ray absorptiometry-measured bone mineral density, and circulating bone metabolism biomarker levels (type I collagen C-telopeptide [CTX], amino-terminal propeptide of type I procollagen [P1NP]). The association of radiographic emphysema, bone metabolism biomarker levels, and pulmonary function with accelerated hip bone mineral density loss, defined by the 75th percentile of annual hip bone mineral density decline, was determined by logistic regression modeling with adjustment for age, sex, inhaled and intermittent steroid use, active smoking, body mass index, and the presence of baseline low hip bone mineral density.

RESULTS

Of those participants with accelerated hip bone mineral density loss, 22% had moderate or severe visually assessed emphysema compared with 7.2% of smokers without accelerated bone mineral density decline. Moderate to severe visually assessed emphysema (odds ratio, 2.84; 95% confidence interval, 1.01-7.98 compared with trace/mild or no visually assessed emphysema) and the 75th percentile of CTX levels (odds ratio, 2.38; 95% confidence interval, 1.20-4.72 compared with CTX levels below the 75th percentile), a marker of bone resorption, were associated with accelerated hip bone mineral density decline after adjustment for covariates and the presence of baseline low hip bone mineral density. FEV₁% predicted was not associated with accelerated bone mineral density decline after adjustment for covariates. Multivariate modeling showed moderate to severe visually assessed emphysema, and the 75th percentiles of CTX were independently associated with accelerated hip bone mineral density decline after adjustment for covariates.

CONCLUSIONS

Emphysema and elevated markers of bone resorption are independently associated with progressive bone mineral density loss in smokers. These clinical markers may guide targeted bone mineral density screening and monitoring in smokers at highest risk.

Repeating Measurement of Bone Mineral Density when Monitoring with Dual-energy X-ray Absorptiometry: 2019 ISCD Official Position

Bone mineral density (BMD) can be measured at multiple skeletal sites using various technologies to aid clinical decision-making in bone and mineral disorders. BMD by dual-energy X-ray absorptiometry (DXA) has a critical role in predicting risk of fracture, diagnosis of osteoporosis, and monitoring patients. In clinical practice, DXA remains the most available and best validated tool for monitoring patients. A quality baseline DXA scan is essential for comparison with all subsequent scans. Monitoring patients with serial measurements requires technical expertise and knowledge of the least significant change in order to determine when follow-up scans should be repeated. Prior ISCD Official Positions have clarified how and when repeat DXA is useful as well as the interpretation of results. The 2019 ISCD Official Positions considered new evidence and clarifies if and when BMD should be repeated. There is good evidence showing that repeat BMD measurement can identify people who experience bone loss, which is an independent predictor of fracture risk. There is good evidence showing that the reduction in spine and hip fractures with osteoporosis medication is proportional to the change in BMD with treatment. There is evidence that measuring BMD is useful following discontinuation of osteoporosis treatment. There is less documentation addressing the effectiveness of monitoring BMD to improve medication adherence, whether monitoring of BMD reduces the risk of fracture, or effectively discriminates patients who should and should not recommence treatment following an interruption of medication. Further research is needed in all of these areas.

Strong Bones, Strong Body

Osteoporosis is a common condition among postmenopausal women. Women 65 years and older should receive bone mineral testing; younger women should undergo risk assessment using a formal risk assessment tool to determine if they should receive bone density testing. Many pharmacologic agents are available to treat women with osteoporosis on bone density testing. Women with previous hip or vertebral fractures should also receive osteoporosis pharmacotherapy.

Hip Fracture Discrimination Based on Statistical Multi-parametric Modeling (SMPM)

Studies using quantitative computed tomography (QCT) and data-driven image analysis techniques have shown that trabecular and cortical volumetric bone mineral density (vBMD) can improve the hip fracture prediction of dual-energy X-ray absorptiometry areal BMD (aBMD). Here, we hypothesize that (1) QCT imaging features of shape, density and structure derived from data-driven image analysis techniques can improve the hip fracture discrimination of classification models based on mean femoral neck aBMD (Neck.aBMD), and (2) that data-driven cortical bone thickness (Ct.Th) features can improve the hip fracture discrimination of vBMD models. We tested our hypotheses using statistical multi-parametric modeling (SMPM) in a QCT study of acute hip fracture of 50 controls and 93 fragility fracture cases. SMPM was used to extract features of shape, vBMD, Ct.Th, cortical vBMD, and vBMD in a layer adjacent to the endosteal surface to develop hip fracture classification models with machine learning logistic LASSO. The performance of these classification models was evaluated in two aspects: (1) their hip fracture classification capability without Neck.aBMD, and (2) their capability to improve the hip fracture classification of the Neck.aBMD model. Assessments were done with 10-fold cross-validation, areas under the receiver operating characteristic curve (AUCs), differences of AUCs, and the integrated discrimination improvement (IDI) index. All LASSO models including SMPM-vBMD features, and the majority of models including SMPM-Ct.Th features performed significantly better than the Neck.aBMD model; and all SMPM features significantly improved the hip fracture discrimination of the Neck.aBMD model (Hypothesis 1). An interesting finding was that SMPM-features of vBMD also captured Ct.Th patterns, potentially explaining the superior classification performance of models based on SMPM-vBMD features (Hypothesis 2). Age, height and weight had a small impact on model performances, and the model of shape, vBMD and Ct.Th consistently yielded better performances than the Neck.aBMD models. Results of this study clearly support the relevance of bone density and quality on the assessment of hip fracture, and demonstrate their potential on patient and healthcare cost benefits.

CT bone density analysis of low-impact proximal femur fractures using Hounsfield units

AIM

To quantify and compare changes in bone mineral density (BMD) via CT analysis in patients with and without spontaneous femoral fractures.

MATERIALS AND METHODS

Consecutive series of patients with CT imaging for spontaneous femoral fractures were compared to the age and gender matched controls. Bone density fixed region of interest measurements were obtained at the site of the fracture, proximally at the femoral head, and distally at the lesser trochanter in fracture patients and controls. Inter- and intrapatient comparisons were performed, including Chi-square and t-test analyses.

RESULTS

24 spontaneous fractures and 25 controls were analyzed with no significant differences in mean age, gender, or body mass index. There were differences in the bone density between the fracture and contralateral non-fracture sides at (p = 0.0001) and distal (p < 0.0001) to the fracture. Proximal and distal bone density differences existed between case fracture and control non-fracture sites (p < 0.0001, p = 0.0001), and between the case non-fracture and control non-fracture sites (p < 0.0001, p < 0.0001). The reliability for measurements was good to excellent proximally (ICC = 0.63-0.87), moderate to excellent at the fracture site (ICC = 0.43-0.78), and fair to good distal (ICC = 0.24-0.68) to the fracture site.

CONCLUSION

Patients with spontaneous femoral fractures exhibit lower bone density than the asymptomatic controls. Bone insufficiency is best demonstrated proximal or distal to, rather than at the fracture site.

Fangchinoline Promotes Autophagy and Inhibits Apoptosis in Osteoporotic Rats

BACKGROUND Osteoporosis is a common disorder leading to bone loss. At present, the treatment options available for the management of osteoporosis are limited. The present investigation evaluated the protective effect of fangchinoline against osteoporosis and also postulates the possible mechanism of action. MATERIAL AND METHODS Osteoporosis was induced by subcutaneously injecting prednisolone (2.5 mg/pellet) for 4 weeks. Fangchinoline 1, 3 and 10 mg/kg was given intraperitoneally for the period. Protective effects of fangchinoline were assessed by estimating microarchitectural parameters and bone mineral density (BMD) in the vertebrae tissues, and biochemical parameters were also determined in the serum of rats with prednisolone-induced osteoporosis. Moreover, gene expression of microtubule-associated protein 1A/1B-light chain 3 (LC3), B cell lymphoma 2 (Bcl-2), caspase-3, bone morphogenetic protein 2 (BMP2), Beclin-1, autophagy-related 5 (ATG-5), Runt-related transcription factor 2 (RUNX-2), and receptor activator of nuclear factor kappa-b ligand (RANKL) protein in the vertebrae tissue were assessed by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot assay. RESULTS There was a significant (p<0.01) decrease in the BMD and microarchitectural parameters in the vertebrae tissue of the fangchinoline-treated group compared to the prednisolone group. We also found that treatment with fangchinoline attenuated the altered expressions of LC3, Bcl-2, caspase-3, BMP2, Beclin-1, ATG-5, RUNX-2, and RANKL protein in the prednisolone-induced osteoporosis rats. Moreover, levels of biochemical parameters were attenuated in the serum of fangchinoline-treated and prednisolone-induced osteoporosis rat. Histopathology revealed that the apoptosis of osteoblasts was decreased in the fangchinoline-treated group compared to the prednisolone group of rats. CONCLUSIONS Fangchinoline inhibits apoptosis of osteoblasts and protects against bone loss in prednisolone-induced osteoporosis rats by inducing autophagy.

Accelerated Bone Loss in Older Men: Effects on Bone Microarchitecture and Strength

Accelerated bone loss (ABL) shown on routine dual-energy X-ray absorptiometry (DXA) may be accompanied by microarchitectural changes, increased cortical porosity, and lower bone strength. To test this hypothesis, we performed a cross-sectional study and used high-resolution peripheral quantitative computed tomography (HR-pQCT) scans (Scanco Medical AG, Brüttisellen, Switzerland) to measure estimated bone strength and microarchitecture in the distal radius and distal and diaphyseal tibia. We studied 1628 men who attended the year 14 exam of the Osteoporotic Fractures in Men (MrOS) study. We retrospectively characterized areal bone mineral density (aBMD) change from the year 7 to year 14 exam in three categories: "accelerated" loss, ≥10% loss at either the total hip or femoral neck (n = 299, 18.4%); "expected" loss, <10% (n = 1061, 65.2%), and "maintained" BMD, ≥0% (n = 268, 16.5%). The ABL cut-off was a safety alert established for MrOS. We used regression models to calculate adjusted mean HR-pQCT parameters in men with ABL, expected loss, or maintained BMD. Men who experienced ABL were older and had a lower body mass index and aBMD and experienced greater weight loss compared with other men. Total volumetric BMD and trabecular and cortical volumetric BMD were lower in men with ABL compared with the expected or maintained group. Men with ABL had significantly lower trabecular bone volume fraction (BV/TV), fewer trabeculae, and greater trabecular separation at both the distal radius and tibia than men with expected loss or who maintained aBMD, all p trend <0.001. Men with ABL had lower cortical thickness and lower estimated bone strength, but there was no difference in cortical porosity except at the tibia diaphyseal site. In summary, men with ABL have lower estimated bone strength, poorer trabecular microarchitecture, and thinner cortices than men without ABL but have similar cortical porosity. These impairments may lead to an increased risk of fracture. © 2018 American Society for Bone and Mineral Research.

Screening to Prevent Osteoporotic Fractures: Updated Evidence Report and Systematic Review for the US Preventive Services Task Force

IMPORTANCE

Osteoporotic fractures cause significant morbidity and mortality.

OBJECTIVE

To update the evidence on screening and treatment to prevent osteoporotic fractures for the US Preventive Services Task Force.

DATA SOURCES

PubMed, the Cochrane Library, EMBASE, and trial registries (November 1, 2009, through October 1, 2016) and surveillance of the literature (through March 23, 2018); bibliographies from articles.

STUDY SELECTION

Adults 40 years and older; screening cohorts without prevalent low-trauma fractures or treatment cohorts with increased fracture risk; studies assessing screening, bone measurement tests or clinical risk assessments, pharmacologic treatment.

DATA EXTRACTION AND SYNTHESIS

Dual, independent review of titles/abstracts and full-text articles; study quality rating; random-effects meta-analysis.

MAIN OUTCOMES AND MEASURES

Incident fractures and related morbidity and mortality, diagnostic and predictive accuracy, harms of screening or treatment.

RESULTS

One hundred sixty-eight fair- or good-quality articles were included. One randomized clinical trial (RCT) (n = 12 483) comparing screening with no screening reported fewer hip fractures (2.6% vs 3.5%; hazard ratio [HR], 0.72 [95% CI, 0.59-0.89]) but no other statistically significant benefits or harms. The accuracy of bone measurement tests to identify osteoporosis varied (area under the curve [AUC], 0.32-0.89). The pooled accuracy of clinical risk assessments for identifying osteoporosis ranged from AUC of 0.65 to 0.76 in women and from 0.76 to 0.80 in men; the accuracy for predicting fractures was similar. For women, bisphosphonates, parathyroid hormone, raloxifene, and denosumab were associated with a lower risk of vertebral fractures (9 trials [n = 23 690]; relative risks [RRs] from 0.32-0.64). Bisphosphonates (8 RCTs [n = 16 438]; pooled RR, 0.84 [95% CI, 0.76-0.92]) and denosumab (1 RCT [n = 7868]; RR, 0.80 [95% CI, 0.67-0.95]) were associated with a lower risk of nonvertebral fractures. Denosumab reduced the risk of hip fracture (1 RCT [n = 7868]; RR, 0.60 [95% CI, 0.37-0.97]), but bisphosphonates did not have a statistically significant association (3 RCTs [n = 8988]; pooled RR, 0.70 [95% CI, 0.44-1.11]). Evidence was limited for men: zoledronic acid reduced the risk of radiographic vertebral fractures (1 RCT [n = 1199]; RR, 0.33 [95% CI, 0.16-0.70]); no studies demonstrated reductions in clinical or hip fractures. Bisphosphonates were not consistently associated with reported harms other than deep vein thrombosis (raloxifene vs placebo; 3 RCTs [n = 5839]; RR, 2.14 [95% CI, 0.99-4.66]).

CONCLUSIONS AND RELEVANCE

In women, screening to prevent osteoporotic fractures may reduce hip fractures, and treatment reduced the risk of vertebral and nonvertebral fractures; there was not consistent evidence of treatment harms. The accuracy of bone measurement tests or clinical risk assessments for identifying osteoporosis or predicting fractures varied from very poor to good.

Osteoporosis: A Review of Treatment Options

Approximately 10 million men and women in the U.S. have osteoporosis,1 a metabolic bone disease characterized by low bone density and deterioration of bone architecture that increase the risk of fractures.2 Osteoporosis-related fractures can increase pain, disability, nursing home placement, total health care costs, and mortality.3 The diagnosis of osteoporosis is primarily determined by measuring bone mineral density (BMD) using noninvasive dual-energy x-ray absorptiometry. Osteoporosis medications include bisphosphonates, receptor activator of nuclear factor kappa-B ligand inhibitors, estrogen agonists/antagonists, parathyroid hormone analogues, and calcitonin.3-6 Emerging therapies utilizing novel mechanisms include a cathepsin K inhibitor and a monoclonal antibody against sclerostin.7,8 While professional organizations have compiled recommendations for the management of osteoporosis in various populations, a consensus has yet to develop as to which is the gold standard; therefore, economic evaluations have been increasingly important to help guide decision-makers. A review of cost-effectiveness literature on the efficacy of oral bisphosphonates has shown alendronate and risedronate to be most cost-effective in women with low BMD without previous fractures.9 Guidelines are inconsistent as to the place in therapy of denosumab (Prolia, Amgen). In economic analyses evaluating treatment of postmenopausal women, denosumab outperformed risedronate and ibandronate; its efficacy was comparable to generic alendronate, but it cost more.10 With regard to older men with osteoporosis, denosumab was also found to be cost-effective when compared with bisphosphonates and teriparatide (Forteo, Lilly).11.

Incidence and Predictors of Repeat Bone Mineral Densitometry: A Longitudinal Cohort Study

BACKGROUND

Existing guidelines for repeat screening and treatment monitoring intervals regarding the use of dual-energy x-ray absorptiometry (DXA) scans are conflicting or lacking. The Choosing Wisely campaign recommends against repeating DXA scans within 2 years of initial screening. It is unclear how frequently physicians order repeat scans and what clinical factors contribute to their use.

OBJECTIVE

To estimate cumulative incidence and predictors of repeat DXA for screening or treatment monitoring in a regional health system.

DESIGN

Retrospective longitudinal cohort study PARTICIPANTS: A total of 5992 women aged 40-84 years who received initial DXA screening from 2006 to 2011 within a regional health system in Sacramento, CA.

MAIN MEASURES

Two- and five-year cumulative incidence and hazard rations (HR) of repeat DXA by initial screening result (classified into three groups: low or high risk of progression to osteoporosis, or osteoporosis) and whether women were prescribed osteoporosis drugs after initial DXA.

KEY RESULTS

Among women not treated after initial DXA, 2-year cumulative incidence for low-risk, high-risk, and osteoporotic women was 8.0%, 13.8%, and 19.6%, respectively, increasing to 42.9%, 60.4%, and 57.4% by 5 years after initial screening. For treated women, median time to repeat DXA was over 3 years for all groups. Relative to women with low-risk initial DXA, high-risk initial DXA significantly predicted repeat screening for untreated women [adjusted HR 1.67 (95% CI 1.40-2.00)] but not within the treated group [HR 1.09 (95% CI 0.91-1.30)].

CONCLUSIONS

Repeat DXA screening was common in women both at low and high risk of progression to osteoporosis, with a substantial proportion of women receiving repeat scans within 2 years of initial screening. Conversely, only 60% of those at high-risk of progression to osteoporosis were re-screened within 5 years. Interventions are needed to help clinicians make higher-value decisions regarding repeat use of DXA scans.

Bone Turnover Markers After Sleep Restriction and Circadian Disruption: A Mechanism for Sleep-Related Bone Loss in Humans

CONTEXT

Sleep abnormalities are associated with low bone mineral density. Underlying mechanisms are unknown.

OBJECTIVE

Investigate the impact of sleep restriction with circadian disruption on bone biomarkers.

DESIGN

Intervention study.

PARTICIPANTS AND METHODS

Four bone biomarkers [C-terminal cross-linked telopeptide of type I collagen (CTX) = bone resorption, N-terminal propeptide of type I procollagen (P1NP) = bone formation, sclerostin and fibroblast growth factor 23 = osteocyte function] were measured in bihourly serum samples over 24 hours at baseline and after ∼3 weeks of sleep restriction (5.6 hours sleep/24 hours) with concurrent circadian disruption (recurring 28-hour "day" in dim light) in 10 men (age groups: 20 to 27 years, n = 6; 55 to 65 years, n = 4). The effects of sleep/circadian disruption and age on bone biomarker levels were evaluated using maximum likelihood estimation in a mixed model for repeated measures.

RESULTS

P1NP levels were lower after intervention compared with baseline (P < 0.001); the decrease in P1NP was greater for younger compared with older men (28.0% vs 18.2%, P < 0.001). There was no change in CTX (Δ = 0.03 ± 0.02 ng/mL, P = 0.10). Sclerostin levels were higher postintervention in the younger men only (Δ = 22.9% or 5.64 ± 1.10 pmol/L, P < 0.001).

CONCLUSIONS

These data suggest that 3 weeks of circadian disruption with concurrent sleep restriction can lead to an uncoupling of bone turnover wherein bone formation is decreased but bone resorption is unchanged. Circadian disruption and sleep restriction may be most detrimental to bone in early adulthood.

Older Men With Anemia Have Increased Fracture Risk Independent of Bone Mineral Density

CONTEXT

Extremely low hemoglobin (Hgb) values have been linked to increased fracture risk at different sites. However, careful assessment of clinically defined anemia and fracture risk is lacking.

OBJECTIVE

To determine whether men with anemia were at increased risk of fracture after accounting for bone mineral density (BMD) and bone loss.

DESIGN

Cross-sectional analysis (at visit 3) and prospective analysis (from baseline to visit 3) in the Osteoporotic Fractures in Men (MrOS), a multisite, longitudinal cohort study.

SETTING

Six communities in the United States.

PARTICIPANTS

A total of 3632 community-dwelling men (age ≥65 years) in MrOS at baseline (2000 through 2002) who were able to walk unassisted, did not have hip replacement or fracture, and had complete blood cell counts at visit 3 (2007 through 2009).

OUTCOMES

Adjudicated spine and nonspine fractures during a median 7.2 years of follow-up.

RESULTS

Analytic baseline characteristics associated with fractures or anemia (defined as Hgb <12 g/dL) were included in multivariable models. Anemia was associated with increased risk of any fracture [hazard ratio (HR), 1.67; 95% confidence interval (CI), 1.26 to 2.21] and nonspine fracture (HR, 1.70; 95% CI, 1.25 to 2.31). A model including change in BMD slightly attenuated the association with any (HR, 1.60; 95% CI, 1.20 to 2.13) and nonspine fractures (HR, 1.57; 95% CI, 1.14 to 2.15). Including absolute BMD did not significantly alter the anemia-fracture association. Anemia was not associated with spine fracture.

CONCLUSIONS

Community-dwelling older men with anemia had a 57% to 72% increase in nonspine fracture risk independent of BMD and bone loss.

Bone mineral density and insulin-like growth factor-1 in children with spastic cerebral palsy

BACKGROUND

Children with cerebral palsy (CP) have significant decrease linear growth rate and low bone mineral density (BMD).

AIMS

This study is to evaluate BMD in children with CP and its relation to the levels of insulin-like growth factor-1 (IGF-1).

SUBJECTS AND METHODS

This cross-sectional study was carried out on 58 children suffering from spastic CP with the age range 4-12 years compared to 19 controls. All assessed by dual energy x-ray absorptiometry (DXA) to measure BMD, serum level of IGF-1, and serum vitamin D. The patients were classified according to their GMFCS.

RESULTS

Fractures were reported in seven (12.1%) of cases. Our study demonstrated that, IGF-1 level and BMD decrease in correlation with the severity of CP. IGF-1correlates positively with serum vitamin D, BMI, and BMD. CP children with severe GMFCS level or who use anticonvulsive drugs are at a high risk for low BMD and low levels of IGF-1.

CONCLUSION

Both BMD and IGF-1 were significantly in low children with spastic CP; IGF-1 negatively correlates with the severity of osteopenia in children with spastic. Children with CP who are not independently ambulant or with severe GMFCS level or who use anticonvulsive drugs are at a high risk for developing low BMD.

Trends and Disparities in Osteoporosis Screening Among Women in the United States, 2008-2014

BACKGROUND

The United States Preventive Services Task Force recommends universal osteoporosis screening among women ages 65+ and targeted screening of younger women, but historically, adherence to these evidence-based recommendations has been suboptimal.

METHODS

To describe contemporary patterns of osteoporosis screening, we conducted a retrospective analysis using the OptumLabs^™ Data Warehouse, a database of de-identified administrative claims, which includes medical and eligibility information for over 100 million Medicare Advantage and commercial enrollees. Study participants included 1,638,454 women ages 50+ with no prior history of osteoporosis diagnosis, osteoporosis drug use, or hip fracture. Osteoporosis screening during the most recent 2-year period of continuous enrollment was assessed via medical claims. Patient sociodemographics, comorbidities, and utilization of other services were also determined using health insurance files.

RESULTS

Overall screening rates were low: 21.1%, 26.5%, and 12.8% among women ages 50-64, 65-79, and 80+ years, respectively. Secular trends differed significantly by age (P <.001). Between 2008 and 2014, utilization among women ages 50-64 years declined 31.4%, changed little among women 65-79, and increased 37.7% among women 80+ years. Even after accounting for socioeconomic status, health status, and health care utilization patterns, non-Hispanic black women were least likely to be screened, whereas non-Hispanic Asian and Hispanic women were most likely to undergo screening. Marked socioeconomic gradients in screening probabilities narrowed substantially over time, decreasing by 44.5%, 71.9%, and 59.7% among women ages 50-64, 65-79 and 80+ years, respectively.

CONCLUSIONS

Despite significant changes in utilization of osteoporosis screening among women ages 50-64 and 80+, in line with national recommendations, tremendous deficiencies among women 65+ remain.

Epigenetic regulation of bone cells

Bone is a major organ in the skeletal system that supports and protects muscles and other organs, facilitates movement and hematopoiesis, and forms a reservoir of minerals including calcium. The cells in the bone, such as osteoblasts, osteoclasts, and osteocytes, orchestrate sequential and balanced regulatory mechanisms to maintain bone and are capable of differentiating in bones. Bone development and remodeling require a precise regulation of gene expressions in bone cells, a process governed by epigenetic mechanisms such as histone modification, DNA methylation, and chromatin structure. Importantly, lineage-specific transcription factors can determine the epigenetic regulation of bone cells. Emerging data suggest that perturbation of epigenetic programs can affect the function and activity of bone cells and contributes to pathogenesis of bone diseases, including osteoporosis. Thus, understanding epigenetic regulations in bone cells would be important for early diagnosis and future therapeutic approaches.

Diagnostic devices for osteoporosis in the general population: A systematic review

INTRODUCTION

A diagnostic gap exists in the current dual photon X-ray absorptiometry (DXA) based diagnostic approach to osteoporosis. Other diagnostic devices have been developed, but no comprehensive review concerning the applicability of these diagnostic devices for population-based screening have been performed.

MATERIAL AND METHODS

A systematic review of Embase, Medline and the Cochrane Central Register for Controlled Trials was performed for population-based studies that focused on technical methods that could either indicate bone mineral density (BMD) by DXA, substitute for DXA in prediction of fracture risk, or that could have an incremental value in fracture prediction in addition to DXA. Quality of included studies was rated by QUADAS 2.

RESULTS

Many other technical devices have been tested in a population-based setting. Five studies aiming to indicate BMD and 17 studies aiming to predict fractures were found. Overall, the latter studies had higher methodological quality. The highest number of studies was found for quantitative ultrasound (QUS). The ability to indicate BMD or predict fractures was moderate to minor for all examined devices, using reported area under the curve (AUC) of Receiver Operating Characteristic curves values as standard.

CONCLUSIONS

Of the methods assessed, only QUS appears capable of perhaps replacing DXA as standalone examination in the future whilst radiographic absorptiometry could provide important information in areas with scarcity of DXA. QUS may be of added value even after DXA has been performed. Evaluation of proposed cutoff-values from population-based studies in separate population-based cohorts is still lacking for most examination devices.

Changes in Nonosteoporotic Bone Density and Subsequent Fractures in Women

OBJECTIVES

Osteopenia is considerably more common than osteoporosis and accounts for most of the fracture burden in women older than 50 years. It is uncertain when to initiate treatment in osteopenia. We sought to determine in women with osteopenia what effect transitioning to lower categories had on subsequent fracturing.

METHODS

We surveyed 1150 women from office-based practices who had initial normal or osteopenic bone mineral densities (BMDs) and who were retested after 5.75 years. We classified categories related to baseline T scores as follows: normal (>-1.0), mild osteopenia (-1.0 to -1.49), moderate osteopenia (-1.5 to -1.99), and severe osteopenia (-2.0 to -2.49). We determined during a 9.6-year follow-up period the fracture occurrence in those who maintained their initial category status or transitioned into lower categories.

RESULTS

Transitioning to lower categories was not significantly different among baseline osteopenic categories but significantly more than normal baseline BMDs. Total fractures, individuals fracturing, and major fractures were significantly more, with baseline T scores of ≤-1.5 (<0.001). Although only 10.2% transitioned to osteoporosis, 90.5% of these transitions occurred with baseline T scores ≤-1.5 and accounted for significantly more fractures than baseline T scores of >-1.5.

CONCLUSIONS

Most subsequent fractures and transitions to osteoporosis occurred with baseline T scores ≤-1.5. Clinical risk factors need to be used to determine at what T score threshold treatment would be cost effective.

Bone Mineral Density as a Predictor of Subsequent Wrist Fractures: Findings From the Women's Health Initiative Study

CONTEXT

Wrist fractures are common among postmenopausal women. Associations of bone mineral density (BMD) and 10-year predicted risk of major osteoporotic fracture (MOF) with wrist fractures are poorly characterized.

OBJECTIVE

The objective was to examine associations between the Fracture Risk Assessment Tool (FRAX)-predicted risk of MOF, BMD, BMD change, and wrist fracture.

DESIGN

This was a prospective observational study with a mean follow-up of 8.5 years.

SETTING

This study included 40 US centers.

PARTICIPANTS

A total of 11 392 participants from the Women's Health Initiative BMD Cohort aged 50-79 years at baseline were included in this study.

INTERVENTIONS

None.

MAIN OUTCOME

The goal was to measure incident wrist fracture.

RESULTS

A FRAX-predicted MOF risk ≥9.3% identified 17% of the women aged <65 years who subsequently experienced wrist fracture. Each one standard deviation lower BMD was associated with higher wrist fracture risk, with adjusted hazard ratio (95% confidence interval) of 1.66 (1.42-1.93) for femoral neck (FN) BMD and 1.45 (1.28-1.64) for lumbar spine BMD. Compared with FN BMD T score ≥ -1.0, wrist fracture adjusted hazard ratios (95% confidence interval) were: 1.51 (1.06-2.16) for a T score between -1.01 and -1.49; 1.93 (1.36-2.72) for T score between -1.50 and -1.99; 2.52 (1.77-3.60) for a T score between -2.00 and -2.49; and 2.65 (1.78-3.95) for a T score ≤ -2.5. Decrease in FN BMD between baseline and year 3 was associated with increased risk of subsequent wrist fracture; however, change in lumbar spine BMD was not.

CONCLUSIONS

Lumbar spine and femoral neck BMDs were associated with incident wrist fracture, but the FRAX threshold recommended to identify screening candidates did not identify the majority of women who subsequently experienced wrist fracture. Improved understanding of determinants of wrist fractures is warranted.

Choosing the tool for osteoporosis risk prediction

PURPOSE OF REVIEW

Predicting fracture risk is a major challenge because it allows the prevention of major osteoporotic fracture in high-risk populations. With the aging of the population, this matter will become of even greater importance. In recent years, novel clinical, biochemical, and imaging tools have been developed to improve the assessment of fracture risk.

RECENT FINDINGS

The present review summarizes novel clinical strategies, Dual energy X-ray absorptiometry (DXA)-derived tools, imaging techniques, and biochemical markers that have been developed recently to improve fracture risk prediction.

SUMMARY

DXA and clinical fracture risk prediction tools are preferential markers of fracture risk. Clinical fracture risk alone might be used if DXA facilities are unavailable. The fracture risk assessment tool may be used in osteoporosis consultation in many countries. Other tools may be used soon after more studies are performed, particularly trabecular bone score, quantitative ultrasound, bone turnover markers. Specific factors for example falls, hip axis length, vertebral fracture assessment could be used in individual patients. This may significantly improve the clinical decision-making.

Osteoporosis epidemiology 2013: implications for diagnosis, risk assessment, and treatment

PURPOSE OF REVIEW

To summarize the recently published studies that provide insights into the changing epidemiology of osteoporosis and fractures.

RECENT FINDINGS

The main themes reviewed are fracture outcomes; trends in fractures rates; fracture risk assessment and monitoring; atypical femoral fractures; male osteoporosis; falls and physical activity; and sarcopenia, obesity, and metabolic syndrome.

SUMMARY

Osteoporotic fractures were found to have long-term consequences on excess mortality (10 years) and economic costs (5 years). The large burden of nonhip nonvertebral fractures has been underestimated. Divergent (but mostly declining) trends in fracture rates were confirmed in several cohorts from around the world. This has significant implications for healthcare planners and clinicians responsible for the care of individuals with osteoporosis, and also impacts on the calibration of fracture prediction tools. Although fracture prediction tools differ in their complexity, performance characteristics are similar when applied to the general population. Large, high-quality comparative studies with different case mixes are needed. Fracture probability does not appear to be responsive enough to support goal-directed treatment at this time. A consensus on the diagnosis of osteoporosis in men has emerged, based upon the same absolute bone density cutoff for both men and women. Finally, a plethora of new data highlight the importance of falls, physical activity, and body composition as contributors to skeletal health.

Cost-effectiveness of fracture prevention in rural women with limited access to dual-energy X-ray absorptiometry

A reduced reimbursement for office-based dual-energy X-ray absorptiometry (DXA) is likely to exacerbate the burden of fractures in rural areas. Our cost-effective analysis suggests that, in areas where access to DXA is limited, treatment for women at high clinical risk for fractures could both improve health and save money.

INTRODUCTION

To evaluate the cost-effectiveness of various fracture prevention strategies for rural women with limited access to dual-energy X-ray absorptiometry (DXA).

METHODS

A Markov model was developed using data from the published literature and the Manitoba Bone Density Program. The participants were a simulated cohort of rural women aged 65 years with travel distance between 10 and 24 mi to the nearest DXA site. The evaluated strategies were (1) watchful waiting, (2) bone mineral density (BMD)-based strategy (i.e., DXA screening followed by pharmacotherapy based on BMD), and (3) clinical risk factor (CRF)-based strategy (i.e., pharmacotherapy for women at high risk for fractures by the World Health Organization Fracture Risk Assessment Tool [FRAX]). The outcome was an incremental cost-effectiveness ratio (ICER) measured by cost per quality-adjusted life-year (QALY) gained. The analysis was preformed from a societal perspective over a lifetime horizon.

RESULTS

In the base-case analysis, the BMD-based strategy had an ICER of $6000 per QALY gained. For those with travel distance between 25 and 39 mi, the BMD-based strategy would have an ICER of $140,800 per QALY gained. For those with travel distance greater than 40 mi, the CRF-based strategy would be more effective and less costly than other strategies.

CONCLUSIONS

In areas where DXA is readily available, DXA screening followed by pharmacotherapy guided by BMD would be preferred. In areas with more limited access to DXA, pharmacotherapy for women at high clinical risk for fractures based on FRAX could both improve health and save money from the societal perspective.