Discordance between quantitative ultrasound and dual-energy X-ray absorptiometry in bone mineral density: The Vietnam Osteoporosis Study

Partial body fat percentage as a predictor of fragility fractures in a large cohort: a cross-sectional study

Objectives

BMI is a component of fracture risk calculators; however, it may be too simplistic to predict fracture risk. There is emerging evidence for the role that fat plays as a predictor of fracture. Partial body fat percentage (PBF%) may be a novel way to predict both hip and non-hip fractures. The aim of this study is to evaluate PBF% as a predictor of fragility fractures.

Methods

A multivariate logistic regression analysis was conducted looking at PBF% as a predicter of both non-hip and hip fractures in an observational cohort. Our results were adjusted for age, biological sex, gender, smoking status, excess alcohol consumption (>3 units/day), current steroid therapy and the T-scores in both femurs. To allow for comparison, the same model was used with BMI, height and weight as the primary predictor of fracture. A subgroup analysis was conducted stratified by fracture site. A sensitivity analysis using a negative binomial regression was conducted.

Results

A total of 31 447 patients were included in our analysis [mean age 64.9 years (s.d. 12.9)]. PBF% was shown to predict all non-hip fractures after adjustment [odds ratio (OR) 22.14 (95% CI 15.08, 32.50)]. Hip fractures were not predicted by our model [OR 4.19 (95% CI 0.43, 41.46)]. Sensitivity analysis demonstrated a lack of predictive capability for hip fracture but not non-hip fractures.

Conclusion

PBF% may be a suitable predictor for all non-hip fractures, independent of confounding variables. More research is needed on whether it can predict hip fractures.

Bone mineral density and the risk of incident dementia: A meta-analysis

BACKGROUND

It is not known whether bone mineral density (BMD) measured at baseline or as the rate of decline prior to baseline (prior bone loss) is a stronger predictor of incident dementia or Alzheimer's disease (AD).

METHODS

We performed a meta-analysis of three longitudinal studies, the Framingham Heart Study (FHS), the Rotterdam Study (RS), and the Rush Memory and Aging Project (MAP), modeling the time to diagnosis of dementia as a function of BMD measures accounting for covariates. We included individuals with one or two BMD assessments, aged ≥60 years, and free of dementia at baseline with follow-up available. BMD was measured at the hip femoral neck using dual-energy X-ray absorptiometry (DXA), or at the heel calcaneus using quantitative ultrasound to calculate estimated BMD (eBMD). BMD at study baseline ("baseline BMD") and annualized percentage change in BMD prior to baseline ("prior bone loss") were included as continuous measures. The primary outcome was incident dementia diagnosis within 10 years of baseline, and incident AD was a secondary outcome. Baseline covariates included age, sex, body mass index, ApoE4 genotype, and education.

RESULTS

The combined sample size across all three studies was 4431 with 606 incident dementia diagnoses, 498 of which were AD. A meta-analysis of baseline BMD across three studies showed higher BMD to have a significant protective association with incident dementia with a hazard ratio of 0.47 (95% CI: 0.23-0.96; p = 0.038) per increase in g/cm2 , or 0.91 (95% CI: 0.84-0.995) per standard deviation increase. We observed a significant association between prior bone loss and incident dementia with a hazard ratio of 1.30 (95% CI: 1.12-1.51; p < 0.001) per percent increase in prior bone loss only in the FHS cohort.

CONCLUSIONS

Baseline BMD but not prior bone loss was associated with incident dementia in a meta-analysis across three studies.

Comparative analysis of bone outcomes between quantitative ultrasound and dual-energy x-ray absorptiometry from the UK Biobank cohort

This large cohort study investigated reliability and validity of heel ultrasound to estimate bone mineral density in adults. Reliability calculated between left and right heels was relatively poor and so was criterion validity assessed relative to dual-energy X-ray absorptiometry. Heel ultrasound should be used cautiously when estimating bone mineral density.

INTRODUCTION

Calcaneal quantitative ultrasound (QUS) may be used as a safe, low cost, and portable means to estimate bone mineral density (BMD) in large cohorts. The purpose of this study was to quantify the reliability and validity of QUS in comparison to dual-energy X-ray absorptiometry (DXA), which is the reference method for BMD measurement and diagnoses of osteopenia and osteoporosis.

METHODS

Bone outcomes measured on the large UK Biobank cohort were used. The reliability of QUS estimated BMD was quantified by comparing values obtained from the left and right heel measured in the same session. Criterion validity was assessed through agreement between QUS and DXA, quantifying correlations, and sensitivity and specificity of osteopenia and osteoporosis diagnoses.

RESULTS

Reliability calculations were made using data from over 216,000 participants demonstrating similar QUS BMD values between left and right heels in the absolute scale (Sd of difference for men: 0.12 and 0.07 g·cm-2). However, when expressed in relative scales, including concordance of quartiles, reliability was poor. Agreement between QUS and DXA was quantified using data from 5042 participants. Low to modest correlations (r = 0.29 to 0.44) were obtained between multiple QUS variables and DXA BMD, with sensitivity identified as very poor (0.05 to 0.23) for osteoporosis, and poor (0.37 to 0.62) for osteopenia diagnoses.

CONCLUSIONS

The findings of this large comparative analysis identify that whilst calcaneal QUS has the potential to produce reliable absolute BMD measurements and demonstrate modest associations with DXA BMD measures, use of that information to make relative statements about participants in the context of the larger population or to appropriately diagnose osteopenia or osteoporosis may be severely limited.

Volatile Constituents and Anti-Osteoporotic Activity of the n-Hexane Extract From Homalomena gigantea Rhizome

This study analyzed the chemical composition and anti-osteoporosis activity of the n-hexane extract of Homalomena gigantea rhizome. Sixty compounds, representing 92.0% of the extract, were identified by gas chromatography-mass spectrometry. Linalool (15.3%), oplopanone (9.8%), ( Ε)-α-atlantone (5.6%), khusinol acetate (5.4%), bullatantriol (4.3%), and β-sitosterol (3.8%) were the main constituents. The anti-osteoporotic activity of the n-hexane extract was determined by measuring alkaline phosphatase (ALP) activity, collagen content, and the mineralization of MC3T3-E1 cells. At concentrations of 4.0 and 20.0 µg/mL, the n-hexane extract increased ALP activity by 8.2% and 23.7%, and increased collagen secretion by MC3T3-E1 cells by 114.9% and 112.4%, respectively. At 4 µg/mL, the extract significantly promoted the mineralization of MC3T3-E1 cells by as much as 133.2% compared to the negative control. These results suggested that H. gigantea rhizome contains a natural anti-osteoporotic compound.

The Effect of Bone Morphogenetic Protein 2 (BMP-2)/Estrogen Composite Nanoparticles on the Differentiation Function of Osteoporotic Bone Marrow Mesenchymal Stem Cells (BMSCs)

The menopausal hormone abnormal changes such as estrogen deficiency and increased FSH secretion in female patients in old age may cause osteoporosis which is plagued by patients. The pathogenesis of osteoporosis is not yet fully understood. BMP in the transforming growth factor-β superfamily is a key member in the process of bone growth and development, among which BMP-2 exerts critical roles. Impaired osteogenic differentiation of bone marrow mesenchymal stem cells (BMSC) contributes to the progress of osteoporosis. BMSC plays an indispensable role in treating osteoporosis and can develop into different directions through induction. As the regenerative medicine nanotechnology has become a new medical method, it is believed that BMSC can be used to treat osteoporosis and other related diseases. Our study analyzed the effects of BMP-2/estrogen composite nanoparticles on the proliferation and differentiation of osteoporotic BMSC cells to provide a reliable reference for the future treatment. Our results showed that BMP-2/estrogen composite nanoparticles promoted BMSC cell proliferation, increased ALP activity, decreased apoptosis rate, increased the expression of Col-1, Runx2 and Osterix, upregulated the osteogenic marker BMP-2. As confirmed by Alizarin Red staining, it could differentiate into osteoblasts and the content of Trap was decreased. In conclusion, our study confirms that BMP-2/estrogen composite nanoparticles can promote BMSC cell proliferation, osteogenic differentiation, and inhibit osteoclast differentiation, thereby providing new treatments and theoretical reference basis for treating osteoporosis.

Evaluation of community-based screening tools for the early screening of osteoporosis in postmenopausal Vietnamese women

Background

Osteoporosis affects people worldwide. However, there are few validated tools for the early screening of osteoporosis in Vietnam. We set out to evaluate the performance of the osteoporosis self-assessment tool for Asians (OSTA) and the osteoporosis screening tool for Chinese (OSTC) for the early screening of osteoporosis in postmenopausal Vietnamese women.

Methods

We analyzed retrospective data from 797 postmenopausal Vietnamese women. The bone mineral density (BMD) in the lumbar vertebrae (L1–L4) and the left and right femoral necks of all participants were measured using dual-energy X-ray absorptiometry (DXA). Osteoporosis was defined as the BMD (T-score) < -2.5. The OSTA and OSTC scores were calculated from the age and weight of participants. Receiver operating characteristic analysis was conducted to compare the performance of the two tools with the BMD measurements by DXA at different anatomical sites.

Results

The rates of osteoporosis determined by BMD varied between anatomical sites, and ranged from 43.4% to 54.7% in the lumbar vertebrae and 29.2% and 8.9% in the left and right femoral necks, respectively. For the vertebrae, the area under the curve (AUC) for OSTA ranged from 70.9% to 73.9% and for OSTC ranged from 68.7% to 71.6%. The predictive value of both tools was higher for femoral necks, with the AUC of OSTA for the left and right femoral necks being 80.0% and 85.8%, respectively. The corresponding figures for OSTC were 80.5% and 86.4%, respectively. The highest sensitivity and specificity of OSTA were 74.6% and 81.4%, while these figures for OSTC were 73.9% and 82.6%, respectively.

Conclusion

OSTA and OSTC were shown to be useful self-assessment tools for osteoporosis detection in Vietnam postmenopausal women. Further research is encouraged to determine the applicability of tools for other populations and settings.

What is normal bone health? A bioarchaeological perspective on meaningful measures and interpretations of bone strength, loss, and aging

Bioarchaeological (the study of archeological human remains together with contextual and documentary evidence) offers a unique vantage point to examine variation in skeletal morphology related to influences such as activity, disease, and nutrition. The human skeleton is composed of a dynamic tissue that is forged by biocultural factors over the entire life course, providing a record of individual, and community history. Various aspects of adult bone health, particularly bone maintenance and loss and the associated skeletal disease osteoporosis, have been examined in numerous past populations. The anthropological study of bone loss has traditionally focused on the signature of postmenopausal aging, costs of reproduction, and fragility in females. The a priori expectation of normative sex-related bone loss/fragility in bioanthropological studies illustrates the wider gender-ideological bias that continues in research design and data analysis in the field. Contextualized data on bone maintenance and aging in the archeological record show that patterns of bone loss do not constitute predictable consequences of aging or biological sex. Instead, the critical examination of bioarchaeological data highlights the complex and changing processes that craft the human body over the life course, and calls for us to question the ideal or "normal" range of bone quantity and quality in the human skeleton, and to critically reflect on what measures are actually biologically and/or socially meaningful.