Does bone mineral density improve the predictive accuracy of fracture risk assessment? A prospective cohort study in Northern Denmark

Development and validation of common data model-based fracture prediction model using machine learning algorithm

The need for an accurate country-specific real-world-based fracture prediction model is increasing. Thus, we developed scoring systems for osteoporotic fractures from hospital-based cohorts and validated them in an independent cohort in Korea. The model includes history of fracture, age, lumbar spine and total hip T-score, and cardiovascular disease.

PURPOSE

Osteoporotic fractures are substantial health and economic burden. Therefore, the need for an accurate real-world-based fracture prediction model is increasing. We aimed to develop and validate an accurate and user-friendly model to predict major osteoporotic and hip fractures using a common data model database.

METHODS

The study included 20,107 and 13,353 participants aged ≥ 50 years with data on bone mineral density using dual-energy X-ray absorptiometry from the CDM database between 2008 and 2011 from the discovery and validation cohort, respectively. The main outcomes were major osteoporotic and hip fracture events. DeepHit and Cox proportional hazard models were used to identify predictors of fractures and to build scoring systems, respectively.

RESULTS

The mean age was 64.5 years, and 84.3% were women. During a mean of 7.6 years of follow-up, 1990 major osteoporotic and 309 hip fracture events were observed. In the final scoring model, history of fracture, age, lumbar spine T-score, total hip T-score, and cardiovascular disease were selected as predictors for major osteoporotic fractures. For hip fractures, history of fracture, age, total hip T-score, cerebrovascular disease, and diabetes mellitus were selected. Harrell's C-index for osteoporotic and hip fractures were 0.789 and 0.860 in the discovery cohort and 0.762 and 0.773 in the validation cohort, respectively. The estimated 10-year risks of major osteoporotic and hip fractures were 2.0%, 0.2% at score 0 and 68.8%, 18.8% at their maximum scores, respectively.

CONCLUSION

We developed scoring systems for osteoporotic fractures from hospital-based cohorts and validated them in an independent cohort. These simple scoring models may help predict fracture risks in real-world practice.

Ireland DXA-FRAX may differ significantly and substantially to Web-FRAX

Appropriate use of FRAX reduces the number of people requiring DXA scans, while contemporaneously determining those most at risk. We compared the results of FRAX with and without inclusion of BMD. It suggests clinicians to carefully consider the importance of BMD inclusion in fracture risk estimation or interpretation in individual patients.

PURPOSE

FRAX is a widely accepted tool to estimate the 10-year risk of hip and major osteoporotic fracture in adults. Prior calibration studies suggest this works similarly with or without the inclusion of bone mineral density (BMD). The purpose of the study is to compare within-subject differences between FRAX estimations derived using DXA and Web software with and without the inclusion of BMD.

METHOD

A convenience cohort was used for this cross-sectional study, consisting of 1254 men and women aged between 40 and 90 years who had a DXA scan and complete validated data available for analysis. FRAX 10-year estimations for hip and major osteoporotic fracture were calculated using DXA software (DXA-FRAX) and the Web tool (Web-FRAX), with and without BMD. Agreements between estimates within each individual subject were examined using Bland-Altman plots. We performed exploratory analyses of the characteristics of those with very discordant results.

RESULTS

Overall median DXA-FRAX and Web-FRAX 10-year hip and major osteoporotic fracture risk estimations which include BMD are very similar: 2.9% vs. 2.8% and 11.0% vs. 11% respectively. However, both are significantly lower than those obtained without BMD: 4.9% and 14% respectively, P < 0.001. Within-subject differences between hip fracture estimates with and without BMD were < 3% in 57% of cases, between 3 and 6% in 19% of cases, and > 6% in 24% of cases, while for major osteoporotic fractures such differences are < 10% in 82% of cases, between 10 and 20% in 15% of cases, and > 20% in 3% of cases.

CONCLUSIONS

Although there is excellent agreement between the Web-FRAX and DXA-FRAX tools when BMD is incorporated, sometimes there are very large differences for individuals between results obtained with and without BMD. Clinicians should carefully consider the importance of BMD inclusion in FRAX estimations when assessing individual patients.

Bone geometry in older adults with subclinical hypothyroidism upon levothyroxine therapy: A nested study within a randomized placebo controlled trial

The effect of levothyroxine (LT4) therapy for subclinical hypothyroidism (SHypo) on appendicular bone geometry and volumetric density has so far not been studied. In a nested study within the randomized, placebo-controlled Thyroid Hormone Replacement for Subclinical Hypothyroidism (TRUST) trial, we assessed the effect of LT4 therapy on bone geometry as measured by peripheral quantitative computed tomography (pQCT). In the TRUST trial, community-dwelling adults aged ≥65 years with SHypo were randomized to LT4 with dose titration vs. placebo with mock titration. We analyzed data from participants enrolled at the TRUST site in Bern, Switzerland who had bone pQCT measured at baseline and at 1 to 2 years follow-up. The primary outcomes were the annual percentage changes of radius and tibia epi- and diaphysis bone geometry (total and cortical cross-sectional area (CSA) and cortical thickness), and of volumetric bone mineral density (bone mineral content (BMC) and total, trabecular and cortical volumetric bone mineral density (vBMD)). We performed linear regression of the annual percentage changes adjusted for sex, LT4 dose at randomization and muscle cross-sectional area. The 98 included participants had a mean age of 73.9 (±SD 5.4) years, 45.9% were women, and 12% had osteoporosis. They were randomized to placebo (n = 48) or LT4 (n = 50). Annual changes in BMC and vBMD were similar between placebo and LT4-treated groups, without significant difference in bone geometry or volumetric bone mineral density changes, neither at the diaphysis, nor at the epiphysis. For example, in the placebo group, epiphyseal BMC (radius) decreased by a mean 0.2% per year, with a similar decrease of 0.5% per year in the LT4 group (between-group difference in %ΔBMC 0.3, 95% CI -0.70 to 1.21, p = 0.91). Compared to placebo, LT4 therapy for an average 14 months had no significant effect on bone mass, bone geometry and volumetric density in older adults with subclinical hypothyroidism. TRIAL REGISTRATION: The trial was registered on ClinicalTrials.gov numbers NCT01660126 (TRUST Thyroid trial) and NCT02491008 (Skeletal outcomes).

Quantitative ultrasound assessment of the effect of parity on bone mineral density in females

Background

The effect of pregnancy and breastfeeding on a female’s bone mineral density (BMD) is controversial. This prospective study aims to investigate the effect of parity on BMD among pre-menopausal multiparous females using quantitative ultrasound as a screening method and females with no pregnancies (nulliparous) as a control group.

Methods

A portable ultrasound-based bone densitometer (DMS PEGASUS SMART, Mauguio, France) was used to indirectly assess the BMD in 51 multiparous (29–45 years) and 51 nulliparous Arabic females (18–35 years) by quantifying the broadband ultrasound attenuation (BUA) from their right calcaneus bone. BUA > 70 db/mhz = normal, BUA 65–69.9 db/mhz = below average, BUA 55–64.9 db/mhz = osteopenia and BUA < 55 db/mhz = osteoporosis.

Results

There was a significant difference in mean BUA between multiparous and nulliparous females (74.1 db/mhz vs. 69.3 db/mhz, p = 0.006). The prevalence of normal BMD was significantly higher in the nulliparous group than in the multiparous group (70.6% vs. 47.1%, p = 0.02). Osteoporosis was found in the multiparous group only (3/51). Among the multiparous females who breastfed (43/51), a total of 51.2% (22/43) had normal BMD, 25.6% (11/43) had BMD below average, 18.6% (8/43) had osteopenia and 4.7% (2/43) had osteoporosis. No significant differences in mean BUA (p = 0.2) were found between the group of females who breastfed for one year (13/43; BUA: 70.5 ± 9.4), the group of females who breastfed for 6–11 months (8/43; BUA: 70.6 ± 10.0) and those who breastfed for less than six months (22/43; BUA: 71.6 ± 9.4). A binary logistic regression model built for predicting BMD normality showed significance for the variable parity (p = 0.03), while the effect of the possible confounding variables BMI and age on BMD normality was found to be non- significant (p = 0.1 and p = 0.6, respectively).

Conclusion

Parity affects the BMD, as assessed by a portable ultrasound-based bone densitometer, of young and middle-aged females as compared to the BMD of nulliparous females.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12905-021-01516-w.

Utility of fragility fracture prediction tools in a group of postmenopausal women

Objectives

Fractures are a common complication of osteoporosis. The main aim of our study was to assess the relation between fractures identified as low energy fractures (fragility), bone mineral density (BMD), trabecular bone score (TBS), and handgrip in a group of postmenopausal women. An additional aim was to determine the relation between fragility fractures and age, height loss, and falls (reported in the last 12 months and 5 years).

Material and methods

The study was conducted in a group of 120 (mean age 69 years; 59-81, SD 5.3) postmenopausal patients who were referred to the Medical Centre for an osteoporosis screening appointment by their general practitioner. All patients were interviewed (with a questionnaire containing questions on fracture risk factors and highest height), had their anthropometric measures taken (current height and weight) as well as TBS analysis following their DXA (dual-energy X-ray absorptiometry) scan and handgrip measure.

Results

Sixty patients from the study group had a history of fractures (with a total of 92 fractures), of whom 39 women (76 fractures) were identified as those with a low-energy fracture. Fragility fractures were more likely to be reported in older patients (Me 71 vs. 68 years, p < 0.05). Differences observed between TBS, handgrip and BMD in reference to fragility fractures were not statistically significant. Analysis showed significant correlations between BMD (neck and L1-L4) and TBS fracture risk categories. Falls reported in the last 5 years and height loss were factors which correlated with fragility fractures (p < 0.05).

Conclusions

Risk of fragility fractures increases with age. Bone mineral density is insufficient as a fracture risk assessment tool. Information on falls and height loss may provide additional data on fracture risk assessment.

Development of chemiluminescence method based on serum type I collagen hydroxyl terminal peptide β special sequence (β-CTX)

The objective of this work is to develop and verify the analytical performance of a chemiluminescence immunoassay for the specific sequence β-carboxy-terminal cross-linking telopeptide of type I collagen (β-CTX) in human serum. Two specific monoclonal antibodies (mAb-8A03 and mAb-3D12) with high affinity for β-CTX were selected, and, under optimized conditions, a chemiluminescence immunoassay method (CLIA) for β-CTX was established. The CLIA of β-CTX detected β-CTX in a wide range of 2.0-6000 ng/L. The recovery rate in serum is 95-105%, the specificity is high, and the cross-reaction rate with common easily interfering substances is low (not more than 0.01%). The CLIA correlates well with Roche electrochemiluminescence immunoassay (ECLIA), with a correlation coefficient of 0.9551, which fully meets the requirements of clinical analysis. The developed β-CTX CLIA kit has high sensitivity and good stability. It has the same performance as the commercial Roche ECLIA kit and can be applied clinically.

Diagnostic, treatment, and follow-up of osteoporosis-position statement of the Latin American Federation of Endocrinology

The Latin American Federation of Endocrinology position statement on osteoporosis was developed by endocrinologists from 9 countries. It encompasses the definition, diagnosis, treatment, and follow-up of the disease, the identification of barriers to healthcare, and proposals to improve the disease care in the region.

INTRODUCTION

There is a gap in the understanding of osteoporosis in Latin America. The objective of this work is to state the position of the Latin American Federation of Endocrinology on osteoporosis care in postmenopausal women to better bridge this gap.

METHODS

An experts' panel was formed comprising of 11 endocrinologists from 9 countries. A data search was conducted with a conceptual approach and data selection was based on the hierarchy of the EBHC pyramid. Unpublished data was considered for local epidemiological data and expert opinion for the identification of barriers to healthcare. An expert consensus based on the Delphi methodology was carried out. Experts were asked to respond on a 5-point Likert Scale to two provided answers to guiding questions.

RESULTS

Consensus was agreed on the answer for the questions with the higher median on the Likert scale and synthetized on 16 statements covering the definition of osteoporosis, diagnostic approach, treatment options, and follow-up. Besides clinical topics, unmet needs in osteoporosis were identified in relation to local epidemiological data, barriers to treatment, and misclassification of programs within health systems.

CONCLUSIONS

Through a process based on recognized methodological tools, FELAEN's position on osteoporosis was developed. This made it possible to state an optimum scenario for the care of the disease and helped to identify knowledge gaps. There is great variability in the approach to osteoporosis in Latin America and barriers in all the stages of healthcare persist.

Fracture Risk Assessment: An Update

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Our ability to accurately identify high fracture risk in individuals has improved as the volume of clinical data has expanded and fracture risk assessment tools have been developed.

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Given its accessibility, affordability, and low radiation exposure, dual x-ray absorptiometry (DXA) remains the standard for osteoporosis screening and monitoring response to treatment.

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The trabecular bone score (TBS) is a DXA software add-on that uses lumbar spine DXA imaging to produce an output that correlates with bone microarchitecture. It has been identified as an independent fracture risk factor and may prove useful in further stratifying fracture risk among those with a bone mineral density (BMD) in the osteopenic range (-1.0 to -2.4 standard deviations), in those with low-energy fractures but normal or only mildly low BMD, or in those with conditions known to impair bone microarchitecture.

➤

Fracture risk assessment tools, including the Fracture Risk Assessment Tool (FRAX), Garvan fracture risk calculator, and QFracture, evaluate the impact of multiple clinical factors on fracture risk, even in the absence of BMD data. Each produces an absolute fracture risk output over a defined interval of time. When used appropriately, these enhance our ability to identify high-risk patients and allow us to differentiate fracture risk among patients who present with similar BMDs.

➤

For challenging clinical cases, a combined approach is likely to improve accuracy in the identification of high-risk patients who would benefit from the available osteoporosis therapies.

FRAX score with and without bone mineral density: a comparison and factors affecting the discordance in osteoporosis treatment in Thais

We investigate the rate of concordance between treatment recommendations of osteoporosis with 10-year probability of hip fracture calculated using FRAX scores with and without BMD. We found that predictions were concordant in 83.8% of patients. However, older age, lower BMD, and FRAX without BMD around the intervention threshold were associated with discordant results. In the discordant group, FRAX with BMD suggested treatment in more participants with lower age, higher BMI, and lower BMD when compared with FRAX without BMD.

INTRODUCTION

The Fracture Risk Assessment Tool (FRAX) is used to calculate the 10-year probability of fracture using important clinical factors, with bone mineral density (BMD) as an optional input variable. We aimed to determine the rate of concordance between treatment recommendations of osteoporosis with 10-year probability of hip fracture calculated using FRAX scores with and without BMD and to identify relevant clinical risk factors associated with discordance.

METHODS

This was a cross-sectional study conducted in patients between 40 and 90 years of age who were screened for osteoporosis by BMD measurement using dual energy X-ray absorptiometry (DXA) from 2010 to 2018 at a university hospital in Thailand. A FRAX questionnaire was administered to determine demographic data and osteoporotic risk factors. FRAX scores with and without BMD were calculated for each participant using the Thai reference, and patients were categorized into either the treatment or non-treatment group based on a cut-off of 3% 10-year probability of hip fracture. When FRAX scores with and without BMD results were consistent, they were considered concordant. Otherwise, they were deemed discordant. Clinical risk factors were compared between the concordant and discordant groups.

RESULTS

A total of 3545 participants were included in the study. The majority (83.8%) were in the concordant group. However, older age, lower BMD, and FRAX without BMD around the intervention threshold were significantly associated with discordant results. In the discordant group, FRAX with BMD suggested treatment in more participants with lower age, higher BMI, and lower BMD when compared with FRAX without BMD.

CONCLUSION

FRAX scores with and without BMD yielded concordant predictions regarding the 10-year probability of hip fracture suggesting pharmacological treatment. However, this concordance declined in elderly and osteoporotic participants and in those with FRAX without BMD around intervention threshold. BMD data may be required in these populations in order to facilitate accurate risk assessment.

New Developments in Fracture Risk Assessment for Current Osteoporosis Reports

PURPOSE OF REVIEW

Identifying individuals at high fracture risk can be used to target those likely to derive the greatest benefit from treatment. This narrative review examines recent developments in using specific risk factors used to assess fracture risk, with a focus on publications in the last 3 years.

RECENT FINDINGS

There is expanding evidence for the recognition of individual clinical risk factors and clinical use of composite scores in the general population. Unfortunately, enthusiasm is dampened by three pragmatic randomized trials that raise questions about the effectiveness of widespread population screening using clinical fracture prediction tools given suboptimal participation and adherence. There have been refinements in risk assessment in special populations: men, patients with diabetes, and secondary causes of osteoporosis. New evidence supports the value of vertebral fracture assessment (VFA), high resolution peripheral quantitative CT (HR-pQCT), opportunistic screening using CT, skeletal strength assessment with finite element analysis (FEA), and trabecular bone score (TBS). The last 3 years have seen important developments in the area of fracture risk assessment, both in the research setting and translation to clinical practice. The next challenge will be incorporating these advances into routine work flows that can improve the identification of high risk individuals at the population level and meaningfully impact the ongoing crisis in osteoporosis management.

Critical thinking about three meta-analyses: can vitamin D alone or with calcium prevent fractures?

Critical thinking is crucially important in both research and practice. This article demonstrates that a lack of critical thinking in two meta-analyses resulted in a conclusion that contradicts another meta-analysis and popular opinions. Kahwati et al. and Zhao et al. drew a conclusion that "Vitamin D supplementation alone or with calcium was not associated with reduced fracture incidence among community-dwelling adults without known vitamin D deficiency, osteoporosis, or prior fracture", which apparently contradicted that of Tang et al. Kahwati et al. and Zhao et al. meta-analyzed vitamin D and/or calcium supplementation, which can decrease fracture risk factors, in a population with no known disorders of bone metabolism or vitamin D deficiency. They concluded that supplementation did not reduce fracture incidence. It is important to note that osteoporosis, which supplementation can prevent, and fractures are two distinct concepts. Zhao et al. presented their conclusion without including the conditions under which their conclusion was true. Subsequently, their conclusion was misleadingly interpreted by the public media as "Vitamin D and Calcium Don't Prevent Bone Fractures" and "Vitamin D Does Not Prevent Falls, Calcium Does Not Prevent Fractures-A $2 Billion Waste of Money". If study conclusions do not specify the applicable conditions, guidelines on medications, including supplements, are clinically unacceptable. Researchers must critically think about every step of their studies, including the way their conclusions are presented.

Bone Turnover Markers and Bone Mineral Density to Predict Osteoporotic Fractures in Older Women: A Retrospective Comparative Study

Objective

To investigate the clinical significance of the detection of bone mineral density (BMD) and bone turnover markers (BTM) in older women with osteoporosis, and to compare their predictive power for osteoporotic fractures (OF).

Methods

In this retrospective study, 96 patients with OF and 107 patients with osteoporosis who were hospitalized in the Department of Orthopedics at the First Affiliated Hospital of Chengdu Medical College were examined from October 2017 to February 2019. All selected patients were divided into either the fracture group (96 cases, 47.3%) or the non‐fracture group (107 cases, 52.7%). BMD was measured by dual‐energy X‐ray absorptiometry (DXA). BTM were detected by electrochemical luminescence: aminoterminal propeptide of type I procollagen (PINP), β‐cross‐linked C‐telopeptide of type I collagen (β‐CTX), and molecular fragment of osteocalcin N terminal (N‐MID). Bone metabolism‐related indicators were detected, including alkaline phosphatase (ALP), calcium (Ca), and phosphorus (P). Independent‐samples t‐tests were used to compare the measurement data between the two groups, one‐way ANOVA to compare the gaps between groups, and binary logistic regression to analyze the correlation of BMD and BTM with OF.

Results

There were no significant differences in age, weight, height, body mass index, age, and time of menopause between the two groups. There were a total of 71 cases (35.0%) in group A (60–70 years), 80 cases (39.4%) in group B (71–80 years), and 52 cases (25.6%) in group C (81–90 years). The fracture group was compared with the non‐fracture group for BMD in the lumbar (0.75 ± 0.05 vs 0.88 ± 0.13, 0.75 ± 0.16 vs 0.87 ± 0.09, 0.74 ± 0.21 vs 0.87 ± 0.12 g/cm²; P < 0.05), BMD in the hip (0.62 ± 0.16 vs 0.74 ± 0.14, 0.61 ± 0.15 vs 0.73 ± 0.0, 0.58 ± 0.13 vs 0.73 ± 0.08 g/cm²; P < 0.05), PINP (83.7 ± 5.7 vs 74.8 ± 5.0, 80.7 ± 4.1 vs 72.1 ± 5.1, 81.2 ± 7.0 vs 68.7 ± 6.3 ng/mL, P < 0.05), and β‐CTX (829.7 ± 91.5 vs 798.8 ± 52.2, 848.1 ± 71.2 vs 812.4 ± 79.0, 867.3 ± 53.1 vs 849.1 ± 67.2 pg./mL, P < 0.05). N‐MID (19.0 ± 6.7 vs 21.3 ± 9.7, 16.2 ± 7.0 vs 18.0 ± 5.3 ng/mL, P < 0.05) in the fracture cases was lower than in the non‐fracture cases for groups B and C, and there was statistical significance. Among the fracture cases, PINP in group A was higher than in group B and C, and β‐CTX in group C was higher than in group A and B (P < 0.05). There was no significant difference in the ALP, P, and Ca between the two groups (P > 0.05). Binary logistic regression analysis showed that for BMD in the lumbar and hip, β‐CTX and OF were significantly correlated (respectively, odds ratio [OR] = −4.182, 95% confidence interval [CI] 1.672–3.448; OR = 6.929, 95% CI 2.586–12.106; OR = 7.572, 95% CI 1.441–3.059), and the differences were statistically significant. PINP and N‐MID were correlated with OF (respectively, OR = 4.213, 95% CI 0.978–1.005; OR = 2.510, 95% CI 1.070–1.134, P > 0.05), the difference was not statistically significant.

Conclusion

Osteoporotic older women, with lower bone density and higher β‐CTX, are more likely to incur OF. β‐CTX is better than BMD at predicting OF and can help in its management and in implementing interventions in high‐risk populations.

Nasal Administration and Plasma Pharmacokinetics of Parathyroid Hormone Peptide PTH 1-34 for the Treatment of Osteoporosis

Nasal delivery of large peptides such as parathyroid 1-34 (PTH 1-34) can benefit from a permeation enhancer to promote absorption across the nasal mucosa into the bloodstream. Previously, we have published an encouraging bioavailability (78%), relative to subcutaneous injection in a small animal preclinical model, for a liquid nasal spray formulation containing the permeation enhancer polyethylene glycol (15)-hydroxystearate (Solutol^® HS15). We report here the plasma pharmacokinetics of PTH 1-34 in healthy human volunteers receiving the liquid nasal spray formulation containing Solutol^® HS15. For comparison, data for a commercially manufactured teriparatide formulation delivered via subcutaneous injection pen are also presented. Tc-99m-DTPA gamma scintigraphy monitored the deposition of the nasal spray in the nasal cavity and clearance via the inferior meatus and nasopharynx. The 50% clearance time was 17.8 min (minimum 10.9, maximum 74.3 min). For PTH 1-34, mean plasma C_max of 5 pg/mL and 253 pg/mL were obtained for the nasal spray and subcutaneous injection respectively; relative bioavailability of the nasal spray was ≤1%. Subsequently, we investigated the pharmacokinetics of the liquid nasal spray formulation as well as a dry powder nasal formulation also containing Solutol^® HS15 in a crossover study in an established ovine model. In this preclinical model, the relative bioavailability of liquid and powder nasal formulations was 1.4% and 1.0% respectively. The absolute bioavailability of subcutaneously administered PTH 1-34 (mean 77%, range 55-108%) in sheep was in agreement with published human data for teriparatide (up to 95%). These findings have important implications in the search for alternative routes of administration of peptides for the treatment of osteoporosis, and in terms of improving translation from animal models to humans.