Ethnic differences in bone health

Adverse effects of tamoxifen treatment on bone mineral density in premenopausal patients with breast cancer: a systematic review and meta-analysis

BACKGROUND

It is well known that adjuvant tamoxifen treatment for breast cancer in postmenopausal women decreased bone loss. However, the effects of adjuvant tamoxifen therapy on bone mineral density (BMD) in premenopausal patients with breast cancer remains uncertain. Tamoxifen would have a potential impact of premenopausal BMD on health. The aim of this meta-analysis was to assess this in premenopausal women with primary breast cancer.

METHODS

Through April 2020, studies reporting BMD changes of lumbar spine or hip in premenopausal women with primary breast cancer treated with adjuvant tamoxifen and tamoxifen plus chemotherapy or ovarian function suppression (OFS) were collected from EMBASE and PubMed. The meta-analysis was performed using random effects model of the standardized mean difference (SMD) of BMD in patients.

RESULTS

A total of 1432 premenopausal patients were enrolled in eight studies, involving 198 patients treated with tamoxifen alone in three studies. After a 3-year median follow-up, adjuvant tamoxifen decreased the lumbar spinal and hip BMD by as much as an SMD of -1.17 [95% confidence interval (CI); -1.58 to -0.76)] and -0.66 (95% CI, -1.55 to 0.23), respectively. In subgroup analysis in patients treated adjuvant tamoxifen and tamoxifen plus chemotherapy or OFS according to follow-up duration, the bone change of < 3 years follow-up group was -0.03 SMD (95% CI, -0.47 to 0.41) and that of ≥ 3 years follow-up group was -1.06 SMD (95% CI, -1.48 to -0.64). Compared with patients who received tamoxifen alone, patients who received combination therapy with chemotherapy or OFS showed lesser bone loss at the lumbar spine.

CONCLUSIONS

Our meta-analysis demonstrated that adjuvant tamoxifen therapy in premenopausal patients caused bone loss after 3 years of follow-up, especially at the lumbar spines. For a definite evaluation of the adverse effects of tamoxifen on bone, it is necessary to accumulate more relevant studies.

Bone Density Screening Rates Among Medicare Beneficiaries: An Analysis with a focus on Asian Americans

PURPOSE

To report osteoporosis screening utilization rates among Asian American (AsA) populations in the USA.

METHODS

We retrospectively assessed the use of dual-energy X-ray absorptiometry (DXA) screening using the Medicare 5% Research Identifiable Files. Using Current Procedural Terminology (CPT) codes indicative of a DXA scan, we identified patients recommended for DXA screening according to the ACR-SPR-SSR Practice Parameters (females ≥ 65 years, males ≥ 70 years). Sociodemographic factors and their association with screening were evaluated using chi-square tests.

RESULTS

There were 80,439 eligible AsA beneficiaries, and 12,102 (15.1%) received osteoporosis screening. DXA rate for women was approximately four times greater than the rate for men (19.8% vs. 5.0%; p < 0.001). AsA beneficiaries in zip codes with higher mean household income (MHI) were more likely to have DXA than those in lower MHI areas (17.6% vs. 14.3%, p < 0.001). AsA beneficiaries aged < 80 were more likely to receive DXA (15.5%) than those aged ≥ 80 (14.1%, p < 0.001). There were 2,979,801 eligible non-AsA beneficiaries, and 496,957 (16.7%) received osteoporosis screening during the study period. Non-Hispanic white beneficiaries had the highest overall screening rate (17.5%), followed by North American Native (13.0%), Black (11.8%), and Hispanic (11.1%) beneficiaries. Comparing AsA to non-AsA populations, there were significantly lower DXA rates among AsA beneficiaries when controlling for years of Medicare eligibility, patient age, sex, location, and mean income (p < 0.001).

CONCLUSION

We found lower than expected DXA screening rates for AsA patients. A better understanding of the barriers and facilitators to AsA osteoporosis screening is needed to improve patient care.

Hemoglobin is associated with BMDs and risk of the 10-year probability of fractures in patients with type 2 diabetes mellitus

Purpose

This study aimed to investigate the associations between hemoglobin (HGB) levels and bone mineral density (BMD) and fracture risk in type 2 diabetes mellitus(T2DM) population of different ages.

Method

This cross-sectional study included 641 patients with T2DM (57.9% males). BMD of the femoral neck (FN), total hip (TH), and lumbar spine (LS) were measured using dual-energy X-ray absorptiometry. The 10-year probability of fracture was assessed using a fracture risk assessment tool (FRAX). HGB and other biochemical indices were measured in a certified laboratory at our hospital. Statistical analysis was performed using SPSS 26.0 and R language (R version 4.1.0). Generalized additive models (GAMs) were used to identify the associations between HGB and BMD and fracture risk.

Results

Patients with osteoporosis have lower HGB levels than the non-osteoporotic population and lower FN BMD in patients with anemia than in the non-anemic population. In patients with T2DM, there was sex- and age-related variability in the correlation between HGB levels and BMDs and fracture risk. In older men, HGB level was an independent determinant of BMD and was positively correlated with FN and TH BMD. In non-older women, HGB level was an independent determinant of BMD and fracture risk, positively associated with BMDs and negatively associated with 10-year probability of fracture risk. GAMs revealed a positive linear association between HGB level and BMDs in non-older female patients but not in older male patients.

Conclusion

Our study provides a new perspective on the association of HGB level and BMDs with fracture risk. Relatively high HGB levels are a protective factor for bone quality in patients with T2DM. However, the bone-protective effect of HGB is influenced by age and sex and persists only in older men and non-older women with T2DM.

Atp6v1h Deficiency Blocks Bone Loss in Simulated Microgravity Mice through the Fos-Jun-Src-Integrin Pathway

The microgravity conditions in outer space are widely acknowledged to induce significant bone loss. Recent studies have implicated the close relationship between Atp6v1h gene and bone loss. Despite this, the role of Atp6v1h in bone remodeling and its molecular mechanisms in microgravity have not been fully elucidated. To address this, we used a mouse tail suspension model to simulate microgravity. We categorized both wild-type and Atp6v1h knockout (Atp6v1h+/-) mice into two groups: regular feeding and tail-suspension feeding, ensuring uniform feeding conditions across all cohorts. Analysis via micro-CT scanning, hematoxylin-eosin staining, and tartrate-resistant acid phosphatase assays indicated that wild-type mice underwent bone loss under simulated microgravity. Atp6v1h+/- mice exhibited bone loss due to Atp6v1h deficiency but did not present aggravated bone loss under the same simulated microgravity. Transcriptomic sequencing revealed the upregulation of genes, such as Fos, Src, Jun, and various integrin subunits in the context of simulated microgravity and Atp6v1h knockout. Real-time quantitative polymerase chain reaction (RT-qPCR) further validated the modulation of downstream osteoclast-related genes in response to interactions with ATP6V1H overexpression cell lines. Co-immunoprecipitation indicated potential interactions between ATP6V1H and integrin beta 1, beta 3, beta 5, alpha 2b, and alpha 5. Our results indicate that Atp6v1h level influences bone loss in simulated microgravity by modulating the Fos-Jun-Src-Integrin pathway, which, in turn, affects osteoclast activity and bone resorption, with implications for osteoporosis. Therefore, modulating Atp6v1h expression could mitigate bone loss in microgravity conditions. This study elucidates the molecular mechanism of Atp6v1h's role in osteoporosis and positions it as a potential therapeutic target against environmental bone loss. These findings open new possibilities for the treatment of multifactorial osteoporosis.

Racial/Ethnic Differences in Bone Mineral Density for Osteoporosis

PURPOSE OF REVIEW

We primarily aim to review differences in bone mineral density (BMD) for osteoporosis among different racial/ethnic groups and to highlight the magnitude of racial/ethnic differences in obesity and diabetes. We also explore the factors contributing to the BMD differences among various subgroups. In addition, we investigate the existing disparities in research, educational initiatives, screening practices, and treatment options for osteoporosis and discuss these findings' clinical and public health implications.

RECENT FINDINGS

Racial/ethnic differences in BMD for osteoporosis exist in the USA and other countries. There are disparities regarding osteoporosis screening and treatment. Understanding the factors contributing to these differences can help develop targeted interventions and policies to reduce their impact. Clinicians should consider the racial/ethnic differences in BMD when making treatment decisions and providing preventive care. Future research could contribute to developing effective strategies for preventing osteoporosis among different racial/ethnic groups. This review offered a comprehensive examination of differences in BMD across various racial and ethnic groups, elucidating the influence of genetic, lifestyle, and cultural factors on these differences. This review also highlighted the disparities in osteoporosis screening, treatment options, research on medical effectiveness, and educational outreach tailored to each subgroup. Recognizing the importance of addressing these inequalities, we present this review to advocate for targeted interventions to reduce disparities in osteoporosis and improve bone health for all populations.

Low bone mineral density is associated with gray matter volume decrease in UK Biobank

Objectives

Previous research has found an association of low bone mineral density (BMD) and regional gray matter (GM) volume loss in Alzheimer's disease (AD). We were interested whether BMD is associated with GM volume decrease in brains of a healthy elderly population from the UK Biobank.

Materials and methods

T1-weighted images from 5,518 women (MAge = 70.20, SD = 3.54; age range: 65-82 years) and 7,595 men (MAge = 70.84, SD = 3.68; age range: 65-82 years) without neurological or psychiatric impairments were included in voxel-based morphometry (VBM) analysis in CAT12 with threshold-free-cluster-enhancement (TFCE) across the whole brain.

Results

We found a significant decrease of GM volume in women in the superior frontal gyri, middle temporal gyri, fusiform gyri, temporal poles, cingulate gyri, precunei, right parahippocampal gyrus and right hippocampus, right ventral diencephalon, and right pre- and postcentral gyrus. Only small effects were found in men in subcallosal area, left basal forebrain and entorhinal area.

Conclusion

BMD is associated with low GM volume in women but less in men in regions afflicted in the early-stages of AD even in a sample without neurodegenerative diseases.

Osteoporosis and Fracture Risk among Older US Asian Adults

PURPOSE OF REVIEW

This review summarizes the current knowledge regarding osteoporosis and fracture among older US Asian adults.

RECENT FINDINGS

Asian adults have lower (areal) bone density than non-Hispanic White adults and thus are more likely to be diagnosed and treated for osteoporosis, despite their lower risk of hip fracture. The latter may relate to favorable characteristics in hip geometry, volumetric bone density, and bone microarchitecture; lower risk of falls; and other clinical factors. The fracture risk calculator FRAX accounts for the lower risk of hip fracture among US Asian adults. However, data on major osteoporotic fracture risk remain limited. Fracture rates also vary by Asian subgroup, which may have implications for fracture risk assessment. Furthermore, among women receiving bisphosphonate drugs, Asian race is a risk factor for atypical femur fracture, an uncommon complication associated with treatment duration. Recent clinical trial efficacy data pertaining to lower bisphosphonate doses and longer dosing intervals may be relevant for Asian adults. More research is needed to inform osteoporosis care of US Asian adults, including risk-benefit considerations and the optimal duration of bisphosphonate treatment. Greater evidence-based guidance for primary fracture prevention among US Asian adults will ensure health equity in the prevention of osteoporotic fractures.

Long-term and sequential treatment for osteoporosis

Osteoporosis is a skeletal disorder that causes impairment of bone structure and strength, leading to a progressively increased risk of fragility fractures. The global prevalence of osteoporosis is increasing in the ageing population. Owing to the chronic character of osteoporosis, years or even decades of preventive measures or therapy are required. The long-term use of bone-specific pharmacological treatment options, including antiresorptive and/or osteoanabolic approaches, has raised concerns around adverse effects or potential rebound phenomena after treatment discontinuation. Imaging options, risk scores and the assessment of bone turnover during initiation and monitoring of such therapies could help to inform individualized treatment strategies. Combination therapies are currently used less often than 'sequential' treatments. However, all patients with osteoporosis, including those with secondary and rare causes of osteoporosis, as well as specific patient populations (for example, young adults, men and pregnant women) require new approaches for long-term therapy and disease monitoring. New pathophysiological aspects of bone metabolism might therefore help to inform and revolutionize the diagnosis and treatment of osteoporosis.

Ethnic determinants of skeletal health in female patients with fragility fracture in a culturally diverse population

Background

Low bone density leads to fragility fracture, with significant impact on morbidity and mortality. While ethnic differences in bone density have been observed in healthy subjects, this has not yet been explored in fragility fracture patients.

Aims

To assess if ethnicity is associated with bone mineral density and serum markers of bone health in female patients who experience fragility fractures.

Methods

219 female patients presenting with at least one fragility fracture at a major tertiary hospital in Western Sydney Australia were studied. Western Sydney is a region with great cultural diversity, comprising people from over 170 ethnicities. Within this cohort, the three largest broad ethnic groups were Caucasians (62.1 %), Asians (22.8 %), and Middle Eastern patients (15.1 %). Location and nature of the presenting fracture and other relevant past medical history were obtained. Bone mineral density, measured by dual-energy X-ray absorptiometry, and bone-related serum markers were compared between ethnicities. Covariates (age, height, weight, diabetes, smoking, and at-risk drinking) were adjusted in multiple linear regression model.

Results

Although Asian ethnicity was associated with lower bone mineral density at the lumbar spine in fragility fracture patients, this association was no longer significant after adjustment for weight. Ethnicity (Asian or Middle Eastern) was not a determinant of bone mineral density at any other skeletal site. Caucasians had lower estimated glomerular filtration rate compared to Asian and Middle Eastern subjects. Serum parathyroid hormone concentrations were significantly lower in Asians compared to other ethnicities.

Conclusion

Asian ethnicity and Middle Eastern ethnicity were not major determinants of bone mineral density at the lumbar spine, femoral neck, or total hip.

Outlining the Clinical Profile of TCIRG1 14 Variants including 5 Novels with Overview of ARO Phenotype and Ethnic Impact in 20 Egyptian Families

TCIRG1 gene mutations underlie osteopetrosis, a rare genetic disorder impacting osteoclast function with consequent brittle bones prone to fracture, in spite of being characterized by increased bone density. The disorder is known to exhibit marked genetic heterogeneity, has no treatment, and is lethal in most instances. There are reports of ethnic variations affecting bone mineral density and variants' expression as diverse phenotypes even within individuals descending from the same pedigree. We herein focus on one of osteopetrosis's three types: the autosomal recessive malignant form (MIM 259700) (ARO) that is almost always associated with severe clinical symptoms. We reviewed the results of about 1800 Egyptian exomes and we did not detect similar variants within our Egyptian dataset and secondary neurological deficit. We studied twenty Egyptian families: sixteen ARO patients, ten carrier parents with at least one ARO affected sib, and two fetuses. They were all subjected to thorough evaluation and TCIRG1 gene sequencing. Our results of twenty-eight individuals descending from twenty Egyptian pedigrees with at least one ARO patient, expand the phenotype as well as genotype spectrum of recessive mutations in the TCIRG1 gene by five novel pathogenic variants. Identifying TCIRG1 gene mutations in Egyptian patients with ARO allowed the provision of proper genetic counseling, carrier detection, and prenatal diagnosis starting with two families included herein. It also could pave the way to modern genomic therapeutic approaches.

The associations between uric acid with BMDs and risk of the 10-year probability of fractures in Chinese patients with T2DM stratified by age and gender

PURPOSE

Accumulating evidence suggests that serum uric acid (SUA) plays a beneficial role in bone health in the general population through antioxidant mechanisms. However, there is controversy over the association between SUA and bone in patients with type 2 diabetes mellitus (T2DM). We aimed to investigate the association of serum UA with BMDs and future fracture risks and its potential influencing factors in those patients.

METHOD

This was a cross-sectional study of 485 patients. BMDs at femoral neck (FN), Troch and the lumbar spine (LS) were measured by DXA. The 10-year probability of fracture risk was assessed using the fracture risk assessment tool (FRAX). SUA level and other biochemical indexes were measured.

RESULTS

There were lower SUA concentrations in patients with osteoporosis/osteopenia compared with those in the normal group, which only existed in non-elderly men and elderly women with T2DM. After adjustment for potential confounders, SUA was positively associated with BMD and negatively with 10-year probability of fracture risk only in non-elderly men and elderly women with T2DM. Multiple stepwise regression analysis showed that SUA was an independent determinant of BMD and 10-year probability of fracture risk, which also occurred in the above patients.

CONCLUSION

These results implied that relatively high SUA is a protective factor for bone in T2DM patients, but the osteoprotective effect of SUA was mediated by age and gender, and persisted only in non-elderly men and elderly women. Large intervention studies are needed to further confirm the outcomes and provide possible explanations.

A combined active shape and mean appearance model for the reconstruction of segmental bone loss

This study investigates the novel combination of an active shape and mean appearance model to estimate missing bone geometry and density distribution from sparse inputs simulating segmental bone loss of the femoral diaphysis. An active shape Gaussian Process Morphable model was trained on healthy right femurs of South African males to model shape. The density distribution was approximated based on the mean appearance of computed tomography images from the training set. Estimations of diaphyseal resections were obtained by probabilistic fitting of the active shape model to sparse inputs consisting of proximal and distal femoral data on computed tomography images. The resulting shape estimates of the diaphyseal resections were then used to map the mean appearance model to the patients' missing bone geometry, constructing density estimations. In this way, resected bone surfaces were estimated with an average error of 2.24 (0.5) mm. Density distributions were approximated within 87 (0.7) % of the intensity of the original target images before the simulated segmental bone loss. These results fall within the acceptable tolerances required for surgical planning and reconstruction of long bone defects.

Current Status of the Diagnosis and Management of Osteoporosis

Osteoporosis has been defined as the silent disease of the 21st century, becoming a public health risk due to its severity, chronicity and progression and affecting mainly postmenopausal women and older adults. Osteoporosis is characterized by an imbalance between bone resorption and bone production. It is diagnosed through different methods such as bone densitometry and dual X-rays. The treatment of this pathology focuses on different aspects. On the one hand, pharmacological treatments are characterized by the use of anti-resorptive drugs, as well as emerging regenerative medicine treatments such as cell therapies and the use of bioactive hydrogels. On the other hand, non-pharmacological treatments are associated with lifestyle habits that should be incorporated, such as physical activity, diet and the cessation of harmful habits such as a high consumption of alcohol or smoking. This review seeks to provide an overview of the theoretical basis in relation to bone biology, the existing methods for diagnosis and the treatments of osteoporosis, including the development of new strategies.

Fat Mass Has Negative Effects on Bone, Especially in Men: A Cross-sectional Analysis of NHANES 2011-2018

CONTEXT

The effect of high levels of obesity on bone health are not clear.

OBJECTIVE

We aimed to examine the associations of body composition and bone mineral density (BMD) in a large, nationally representative population with a wide range of body mass index.

METHODS

We analyzed 10 814 subjects aged 20-59 from NHANES 2011-2018 who had total body BMD and body composition data. Body composition was examined as lean mass index (LMI) and fat mass index (FMI). Linear regression models were created with BMD as the outcome, while examining LMI and FMI and controlling for age, gender, race/ethnicity, height, and smoking status.

RESULTS

In multivariable modeling, every 1 kg/m2 additional LMI was associated with 0.19 higher T-score, while every additional 1 kg/m2 in FMI was associated with 0.10 lower T-score (P < .001 for both). The negative association of FMI with BMD was mainly seen when adjusting for LMI. Effects of LMI were similar in men and women, but the effect of FMI was more negative in men (0.13 lower T-score per additional 1 kg/m2 of FMI in men vs 0.08 lower BMD T-score in women, P for interaction < .001).

CONCLUSION

In subjects under 60 years old, lean mass had a strong positive association with BMD. Conversely, fat mass had a moderate, negative association with BMD that was most notable in men at high levels of fat. Our results emphasize the importance of bone health in obesity and may explain site-specific increases in fracture rates in some studies of obese subjects.

Why Aboriginal and Torres Strait Islander Australians fall and fracture: the codesigned Study of Indigenous Muscle and Bone Ageing (SIMBA) protocol

OBJECTIVES

Aboriginal and Torres Strait Islander Australians have a substantially greater fracture risk, where men are 50% and women are 26% more likely to experience a hip fracture compared with non-Indigenous Australians. Fall-related injuries in this population have also increased by 10%/year compared with 4.3%/year in non-Indigenous Australians. This study aims to determine why falls and fracture risk are higher in Aboriginal and Torres Strait Islander Australians.

SETTING

All clinical assessments will be performed at one centre in Melbourne, Australia. At baseline, participants will have clinical assessments, including questionnaires, anthropometry, bone structure, body composition and physical performance tests. These assessments will be repeated at follow-up 1 and follow-up 2, with an interval of 12 months between each clinical visit.

PARTICIPANTS

This codesigned prospective observational study aims to recruit a total of 298 adults who identify as Aboriginal and Torres Strait Islander and reside within Victoria, Australia. Stratified sampling by age and sex will be used to ensure equitable distribution of men and women across four age-bands (35-44, 45-54, 55-64 and 65+ years).

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary outcome is within-individual yearly change in areal bone mineral density at the total hip, femoral neck and lumbar spine assessed by dual energy X-ray absorptiometry. Within-individual change in cortical and trabecular volumetric bone mineral density at the radius and tibia using high-resolution peripheral quantitative computed tomography will be determined. Secondary outcomes include yearly differences in physical performance and body composition.

ETHICAL APPROVAL

Ethics approval for this study has been granted by the Monash Health Human Research Ethics Committee (project number: RES-19-0000374A).

TRIAL REGISTRATION NUMBER

ACTRN12620000161921.

Reference microarchitectural values measured by HR-pQCT in a Franco-Swiss cohort of young adult women

Bone microarchitecture assessed by high-resolution peripheral quantitative computed tomography varies across populations of different origin. The study presents a reference dataset of microarchitectural parameters in a homogeneous group of participants aged within 22-27 range determined by a discriminant analysis of a larger cross-sectional cohort of 339 women.

INTRODUCTION

High-resolution peripheral quantitative computed tomography (HR-pQCT) non-invasively measures three-dimensional bone microarchitectural parameters and volumetric bone mineral density. Previous studies established normative reference HR-pQCT datasets for several populations, but there were few data assessed in a reference group of young women with Caucasian ethnicity living in Western Europe. It is important to obtain different specific reference dataset for a valid interpretation of cortical and trabecular microarchitecture data. The aim of our study was to find the population with the most optimal bone status in order to establish a descriptive reference HR-pQCT dataset in a young and healthy normal-weight female cohort living in a European area including Geneva, Switzerland, Lyon and Saint-Etienne, France.

METHODS

We constituted a cross-sectional cohort of 339 women aged 19-41 years with a BMI > 18 and < 30 kg/m². All participants had HR-pQCT measurements at both non-dominant distal radius and tibia sites.

RESULTS

We observed that microarchitectural parameters begin to decline before the age of 30 years. Based on a discriminant analysis, the optimal bone profile in this population was observed between the age range of 22 to 27 years. Consequently, we considered 43 participants aged 22-27 years to establish a reference dataset with median values and percentiles.

CONCLUSION

This is the first study providing reference values of HR-pQCT measurements considering specific age bounds in a Franco-Swiss female cohort at the distal radius and tibia sites.

Inflammatory status, body composition and ethnic differences in bone mineral density: The Southall and Brent Revisited Study

Ethnic differences in bone mineral density (BMD) and fracture risk are well-described; the aim of this study was to investigate whether central adiposity or inflammatory status contribute to these ethnic differences in BMD in later life. The Southall and Brent Revisited study (SABRE) is a UK-based tri-ethnic cohort of men and women of European, South Asian or African Caribbean origin. At the most recent SABRE follow-up (2014-2018), in addition to measures of cardiometabolic phenotype, participants had dual-energy X-ray absorptiometry (DXA) bone and body composition scans. Multiple linear regression was used to determine whether markers of body composition, central adiposity or inflammatory status contributed to ethnic differences in BMD. In men and women, age- and height-adjusted BMD at all sites was higher in African Caribbeans compared to Europeans (femoral neck: standardised β (95% confidence interval): men: 1.00SD (0.75, 1.25); women: 0.77SD (0.56, 0.99)). South Asian men had higher BMD than European men at the hip (femoral neck: 0.34SD (95%CI: 0.15, 0.54)). Although adjustment for body mass index (BMI) or lean mass index (LMI) at the lumbar spine reduced the size of the difference in BMD between African Caribbean and European men (age and height adjusted difference: 0.35SD (0.08, 0.62); age and BMI adjusted difference: 0.25SD (-0.02, 0.51)), in both men and women ethnic differences remained after adjustment for measures of central adiposity (estimated visceral adipose tissue mass (VAT mass) and android to gynoid ratio) and inflammation (interleukin-6 (logIL-6) and C-reactive protein (logCRP)). Furthermore, in women, we observed ethnic differences in the relationship between BMI (overall interaction: p = 0.04), LMI (p = 0.04) or VAT mass (p = 0.009) and standardised lumbar spine BMD. In this tri-ethnic cohort, ethnic differences in BMD at the femoral neck, total hip or lumbar spine were not explained by BMI, central adiposity or inflammatory status. Given ethnic differences in fracture incidence, it is important to further investigate why ethnic differences in BMD exist.

Age, Sex, and Race/Ethnicity Associations between Fat Mass and Lean Mass with Bone Mineral Density: NHANES Data

Rising rates of obesity and osteoporosis have public health implications; hence, understanding the relationships between body composition (fat mass (FM) and lean mass (LM)) and bone mineral density (BMD) is important. The purpose of this study is to investigate these associations in a large representative sample. A cross-sectional analysis was conducted using National Health and Nutrition Examination Survey participants (n = 1717, age 44.1 ± 14.2 years) who had complete dual energy x-ray absorptiometry (total BMD g/cm², FM kg, and LM kg) and covariate data. Hierarchical linear regression models were fitted, controlling for demographic and behavioral covariates. Stratum-specific models were fitted by race, sex, and age group. Significant negative associations were found for FM and BMD (β = −0.003) and significant positive associations for LM and BMD (β = 0.007). Stratum-specific analyses by race were consistent between groups, while variations in negative association magnitudes were seen in FM for sex (males β = −0.005 vs. females β = −0.002) and age (under 45 years of age β = −0.005 vs. 45 years and older β = −0.002). Consistent positive linear associations in total and stratum-specified models between LM and BMD could suggest a potential mechanical influence on bone health. The biological mechanisms driving the magnitude variations between FM and BMD by sex and age require more investigation.

Prevalence of Sarcopenia and Relationships Between Muscle and Bone in Indian Men and Women

Both ethnicity and age are important determinants of musculoskeletal health. We aimed to determine the prevalence of sarcopenia, assess the suitability of current diagnostic guidelines, and explore muscle-bone relationships in adults from India. A total of 1009 young (20-35 years) and 1755 older (> 40 years) men and women from existing studies were collated and pooled for the analysis. Dual-energy x-ray absorptiometry measured areal bone mineral density (aBMD) at the hip and spine, and fat and lean mass; hand dynamometer measured hand grip strength (HGS). Indian-specific cut-points for appendicular lean mass (ALM), ALM index (ALMI) and HGS were calculated from young Indian (-2SD mean) populations. Sarcopenia was defined using cut-points from The Foundations for the National Institutes of Health (FNIH), revised European Working Group on Sarcopenia in Older People (EWGSOP2), Asian Working Group for Sarcopenia (AWGS), and Indian-specific cut-points. Low lean mass cut-points were then compared for their predictive ability in identifying low HGS. The relationship between muscle variables (ALM, ALMI, HGS) and aBMD was explored, and sex differences were tested. Indian-specific cut-points (men-HGS:22.93 kg, ALM:15.41 kg, ALMI:6.03 kg/m²; women-HGS:10.76 kg, ALM:9.95 kg, ALMI:4.64 kg/m²) were lower than existing definitions. The Indian-specific definition had the lowest, while EWGSOP2 ALMI had the highest predictive ability in detecting low HGS (men:AUC = 0.686, women:AUC = 0.641). There were sex differences in associations between aBMD and all muscle variables, with greater positive associations in women than in men. The use of appropriate cut-points for diagnosing low lean mass and physical function is necessary in ethnic populations for accurate sarcopenia assessment. Muscle-bone relationships are more tightly coupled during ageing in Indian women than men.

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.

Isolated human crystalline lens three-dimensional shape: A comparison between Indian and European populations

There have been many studies on lens properties in specific populations (e.g. in China, Europe, Singapore, etc.) some of which suggest there may be differences between populations. Differences could be caused by ethnic or environmental influences or experimental procedures. The purpose of this study is to evaluate if any differences exist between Indian and European populations in the central geometric and full shape properties of human lenses. Two custom-developed spectral domain optical coherence tomography systems were used to acquire the crystalline lens geometry: one in India (69 lenses from 59 donors) and the other in Spain (24 lenses from 19 donors). The steps for obtaining accurate 3-D models from optical coherence tomography raw images comprised of image segmentation, fan and optical distortion correction, tilt removal and registration. The outcome variables were lens equatorial diameter, lens thickness, anterior and posterior lens thicknesses and their ratio, central radius of curvature of the anterior and posterior lens surfaces, lens volume and lens surface area. A mixed effects model by maximum likelihood estimation was used to evaluate the effect of age, population and their interaction (age*population) on lens parameters. After adjusting for age, there were no population differences observed in anterior and posterior radii of curvature, equatorial diameter, lens thickness, anterior and posterior lens thicknesses and their ratio, volume and surface area (all p ≥ 0.08). There was also no effect of the interaction term on anterior and posterior radii of curvature, equatorial diameter, lens thickness, anterior and posterior lens thicknesses and their ratio, volume and surface area (all p ≥ 0.06). All central geometric and full shape parameters appeared to be comparable between the European and Indian populations. This is the first study to compare geometric and full shape lens parameters between different populations in vitro.

Bone mineral density in healthy adult Indian population: the Chandigarh Urban Bone Epidemiological Study (CUBES)

Osteoporosis is a disease with a high burden of morbidity. For its accurate diagnosis, using indigenous data as reference standards is needed. However, normative data on bone density is lacking in India. Therefore, we aimed to determine the reference range for bone density for the healthy population of north India.

INTRODUCTION

Osteoporosis is a major public health problem around the globe including India, resulting in significant morbidity, mortality, and health care burden. However, the reference values used for its diagnosis are largely based on data from the western population, which may lead to over- or underdiagnosis of osteoporosis in Indians. Our study aimed to determine the reference range for bone mineral density for the healthy population of India.

METHODS

This is a cross-sectional study of 825 subjects (men 380, women 445) (median age: 41 years, IQR 32-55 years), recruited by a house-to-house survey. The population was stratified into decade-wise groups and biochemical measurements including renal and liver function tests, glycated hemoglobin, serum calcium, 25-hydroxyvitamin D, parathyroid hormone, and bone mineral density were performed in all the subjects. The T-scores for men aged > 50 years and post-menopausal women were calculated based on the data generated from this study in young men and women aged 20-40 years.

RESULTS

According to the BMD manufacturer's data, which is based on the western population, 70% of the Indian men (> 50 years) and 48% of the post-menopausal Indian women had osteopenia while 18% of the men and 25% of the women had osteoporosis. However, according to the re-calculated T-scores from the current study, only 56% and 7.2% of men and 33% and 5% of women had osteopenia and osteoporosis, respectively. An age-related decline in bone mineral density, as seen in the western population, was also seen in both Indian men and women.

CONCLUSION

We have established a reference database for BMD in healthy Indian adult population, which may have clinical implications for the diagnosis and intervention strategies for the management of osteoporosis.

Reference values for bone mineral density in healthy Mexican children and adolescents

INTRODUCTION

Clinical assessment of bone health by Dual-Energy X-ray Absorptiometry (DXA) in the paediatric population requires robust reference values. The International Society for Clinical Densitometry (ISCD) recommends that country/regional reference values ideally should be used to improve precision in bone health assessment.

OBJECTIVE

The aim of this study was to provide reference values for relevant bone health variables for healthy Mexican children and adolescents aged 5 to 18 years.

METHODS

This was a cross-sectional, stratified and population-based study, that measured a representative sample of healthy Mexican children and adolescents with DXA. We constructed age- and sex-smoothed reference values for areal bone mineral density (aBMD) of total body less head (TBLH), total body (TB), lumbar spine (LS), and bone mineral apparent density (BMAD) for LS, by means of Generalized Additive Models for Location, Scale and Shape (GAMLSS).

RESULTS

Reference data including the 3th, 5th, 10th, 25th, 50th, 75th, 90th, 95th and 97th centiles, along with lambda (L), mu (M) and sigma (S) values, are given for each variable of interest for each sex at 0.25 years intervals. Reference values relative to height and Tanner-stage for both sexes are also provided. Finally, formulas to enable Z score estimation for clinical use are also presented CONCLUSIONS: The sex, age, height, Tanner-stage and ethnic-specific reference data provided in this study should enable more precise assessment of bone health in the Mexican paediatric population. The data presented may also allow for future evaluation of potential similarities and differences across different ethnic groups.

Sacral morphometrics for sex estimation of dead cases in Central Thailand

Sex estimation by various forensic anthropology approaches is a crucial factor for identification of human skeletal remains. However, inexpensive, uncomplicated and reliable methods are still required, especially in a remote crime scene and a high crime incidence area. Here, we examined 13 sacral parameters from 78 independent skeletons derived from deceases found in Central Thailand (male, n = 46; female, n = 32) using simple standard anthropometric techniques for sex allocation. Discriminant analysis exhibited that anterior-posterior diameter of S₁ vertebra corpus (APS) is the most accurate sacral parameter for sex determination in our study with 82.1% of correct discrimination rate. The accuracy could be improved up to 97.4% when additional three sacral variables including the length of sacrum measured from the medial anterior-superior sacral promontory to the medial anterior-inferior S₅ vertebra (ASL), alar index (ALI), and the maximum anterior breadth of sacrum measured across sacral alar (ABS) were computed together with APS. These encourage the use of sacral morphometrics for sex assessment of human sacrum remains in Central Thailand. However, further investigation with broadening sacral morphometric data across the country might provide a promising sex determination equation from a sacral skeleton for Thai population.

Different reference ranges affect the prevalence of osteoporosis and osteopenia in an urban adult Malaysian population

OBJECTIVES

To determine the prevalence of osteopenia (OPe) and osteoporosis (OP) in an urban adult population in Malaysia, and to compare the change in the prevalence when using a Caucasian compared to an Asian reference range.

METHODS

A cross-sectional random sample of the population aged between 45 and 90 years from the state of Selangor, Malaysia, was invited to attend a bone health check-up. Participants with diseases known to affect bone metabolism or who were on treatment for OP were excluded. Bone mineral density was measured using dual energy X-ray absorptiometry. Based on the World Health Organization definitions, the prevalence of OPe and OP was calculated using the Asian and Caucasian T-scores.

RESULTS

A total of 342 subjects (222 females, 120 males), with a mean age of 59.68 (standard deviation: 8.89) years, who fulfilled the study criteria were assessed. Based on the Asian reference range, there were 140 (40.9%) subjects with OPe and 48 (14.0%) with OP. On applying the Caucasian reference range, there were 152 (44.4%) subjects with OPe and 79 (23.1%) with OP, with significant increases in males, females, and Chinese ethnic groups. Overall, 75 (21.9%) of subjects had a change in their diagnostic status. T-scores were consistently lower when the Caucasian reference range was used.

CONCLUSIONS

In a healthy urban Malaysian population, the prevalence of OP is 14.0% and OPe is 40.9%. Application of a Caucasian reference range significantly increased the number of subjects with OP and may potentially lead to over-treatment.

Ethnic Differences in Bone Microarchitecture

PURPOSE OF THE REVIEW

The aim of this review is to briefly introduce updates in global fracture epidemiology and then to highlight recent contributions to understanding ethnic differences in bone density, geometry and microarchitecture and consider how these might contribute to differences in fracture risk. The review focuses on studies using peripheral quantitative computed tomography techniques.

RECENT FINDINGS

Recent studies have contributed to our understanding of the differences in fracture incidence both between countries, as well as between ethnic groups living within the same country. In terms of understanding the reasons for ethnic differences in fracture incidence, advanced imaging techniques continue to increase our understanding, though there remain relatively few studies. It is a priority to continue to understand the epidemiology, and changes in the patterns of, fracture, as well as the underlying phenotypic and biological reasons for the ethnic differences which are observed.

Pathophysiological Perspective of Osteoarthritis

Osteoarthritis (OA) is the most well-known degenerative disease among the geriatric and is a main cause of significant disability in daily living. It has a multifactorial etiology and is characterized by pathological changes in the knee joint structure including cartilage erosion, synovial inflammation, and subchondral sclerosis with osteophyte formation. To date, no efficient treatment is capable of altering the pathological progression of OA, and current therapy is broadly divided into pharmacological and nonpharmacological measures prior to surgical intervention. In this review, the significant risk factors and mediators, such as cytokines, proteolytic enzymes, and nitric oxide, that trigger the loss of the normal homeostasis and structural changes in the articular cartilage during the progression of OA are described. As the understanding of the mechanisms underlying OA improves, treatments are being developed that target specific mediators thought to promote the cartilage destruction that results from imbalanced catabolic and anabolic activity in the joint.

Warmth Prevents Bone Loss Through the Gut Microbiota

Osteoporosis is the most prevalent metabolic bone disease, characterized by low bone mass and microarchitectural deterioration. Here, we show that warmth exposure (34°C) protects against ovariectomy-induced bone loss by increasing trabecular bone volume, connectivity density, and thickness, leading to improved biomechanical bone strength in adult female, as well as in young male mice. Transplantation of the warm-adapted microbiota phenocopies the warmth-induced bone effects. Both warmth and warm microbiota transplantation revert the ovariectomy-induced transcriptomics changes of the tibia and increase periosteal bone formation. Combinatorial metagenomics/metabolomics analysis shows that warmth enhances bacterial polyamine biosynthesis, resulting in higher total polyamine levels in vivo. Spermine and spermidine supplementation increases bone strength, while inhibiting polyamine biosynthesis in vivo limits the beneficial warmth effects on the bone. Our data suggest warmth exposure as a potential treatment option for osteoporosis while providing a mechanistic framework for its benefits in bone disease.

Osteosarcopenia in Reproductive-Aged Women with Polycystic Ovary Syndrome: A Multicenter Case-Control Study

CONTEXT

Osteosarcopenia (loss of skeletal muscle and bone mass and/or function usually associated with aging) shares pathophysiological mechanisms with polycystic ovary syndrome (PCOS). However, the relationship between osteosarcopenia and PCOS remains unclear.

OBJECTIVE

We evaluated skeletal muscle index% (SMI% = [appendicular muscle mass/weight (kg)] × 100) and bone mineral density (BMD) in PCOS (hyperandrogenism + oligoamenorrhea), and contrasted these musculoskeletal markers against 3 reproductive phenotypes (i): HA (hyperandrogenism + eumenorrhea) (ii); OA (normoandrogenic + oligoamenorrhea) and (iii), controls (normoandrogenic + eumenorrhea). Endocrine predictors of SMI% and BMD were evaluated across the groups.

DESIGN, SETTING, AND PARTICIPANTS

Multicenter case-control study of 203 women (18-48 years old) in New York State.

RESULTS

PCOS group exhibited reduced SMI% (mean [95% confidence interval (CI)]; 26.2% [25.1,27.3] vs 28.8% [27.7,29.8]), lower-extremity SMI% (57.6% [56.7,60.0] vs 62.5% [60.3,64.6]), and BMD (1.11 [1.08,1.14] vs 1.17 [1.14,1.20] g/cm2) compared to controls. PCOS group also had decreased upper (0.72 [0.70,0.74] vs 0.77 [0.75,0.79] g/cm2) and lower (1.13 [1.10,1.16] vs 1.19 [1.16,1.22] g/cm2) limb BMD compared to HA. Matsuda index was lower in PCOS vs controls and positively associated with SMI% in all groups (all Ps ≤ 0.05). Only controls showed associations between insulin-like growth factor (IGF) 1 and upper (r = 0.84) and lower (r = 0.72) limb BMD (all Ps < 0.01). Unlike in PCOS, IGF-binding protein 2 was associated with SMI% in controls (r = 0.45) and HA (r = 0.67), and with upper limb BMD (r = 0.98) in HA (all Ps < 0.05).

CONCLUSIONS

Women with PCOS exhibit early signs of osteosarcopenia when compared to controls likely attributed to disrupted insulin function. Understanding the degree of musculoskeletal deterioration in PCOS is critical for implementing targeted interventions that prevent and delay osteosarcopenia in this clinical population.

Osteoporosis in Africa-where are we now

Africa is experiencing an exponential increase in the number of older persons. The number of persons surviving with human immunodeficiency virus is simultaneously increasing due to improved availability of anti-retroviral therapy. The burden of non-communicable diseases, in particular, osteoporosis and its consequent fragility fractures, is also predicted to increase. Osteoporosis, however, remains a neglected disease and there are no age-standardized reference data available to accurately screen and diagnose individuals with osteoporosis. Epidemiological studies reporting the incidence of hip fracture or vertebral fractures are limited from Africa, especially Sub-Saharan Africa. The studies are usually limited as they are based on a retrospective data and small study numbers and often from a single study site. However, compared with early initial studies, the more recent studies show that osteoporosis and fractures are increasing across the continent. The overall incidence rates for osteoporosis and fractures still vary greatly between different regions in Africa and ethnic groups. Predisposing factors are similar with those in developed countries, but awareness of osteoporosis is sorely lacking. There is a lack of awareness among the population as well as health authorities, making it extremely difficult to quantify the burden of disease. There is great potential for research into the need and availability of preventive strategies. The FRAX® tool needs to be developed for African populations and may circumvent the shortage of bone densitometry.

Preclinical safety and efficacy of 24R,25-dihydroxyvitamin D3 or lactosylceramide treatment to enhance fracture repair

Background/Objective

Cyp24a1-null mice deficient in 24,25(OH)₂D₃ display impaired callus formation during the endochondral phase of bone fracture repair. The 24,25(OH)₂D₃ metabolite acted by binding to the TLC domain containing 3B isoform 2 (TLCD3B2, previously named FAM57B2) effector protein, which then synthesizes lactosylceramide (LacCer). Treatment with 24,25(OH)₂D₃ or LacCer restored callus size and mechanical properties in Cyp24a1-null mice.

Methods

To assess the safety of these molecules and test their efficacy for bone healing in wild-type, non-genetically modified mice, we treated 12-week-old, osteotomized C57BL/6 female mice with each compound for up to 21 days post-osteotomy. Control cohorts were injected with vehicle.

Results

Neither compound was found to exhibit any nephro- nor hepato-toxicity. Calcemia remained stable throughout the experiment and was unaffected by either treatment. Supplementation with 24,25(OH)₂D₃ increased circulating levels of this metabolite about 8-fold, decreased 1,25(OH)₂D₃ levels, and significantly increased circulating 1,24,25(OH)₃D₃ levels, suggesting 1?-hydroxylation of 24,25(OH)₂D₃. TLCD3B2 was found to be expressed in fracture callus at the surface of unmineralized or pre-mineralized cartilage on day 10 and day 12 post-osteotomy and to progressively recede to become undetectable by day 18. Treatment with 24,25(OH)₂D₃ or LacCer reduced the number of TLCD3B2-positive cells. Both treatments also significantly increased stiffness and elastic modulus of the healing bone callus.

Conclusion

Exogenous administration of 24,25(OH)₂D₃ or LacCer improved the biomechanical properties of repaired bones in wild-type animals without affecting circulating calcium levels or other blood parameters, demonstrating preclinical safety and efficacy.

Translational potential

Our data suggest the use of 24R,25-dihydroxyvitamin D₃ or lactosylceramide for ameliorating fracture healing in clinical practice.

Computed Tomography Scan Assessment of the Anatomy of the Pterygomaxillary Junction and Its Relevance in Le Fort I Osteotomy

Knowledge of the morphometry and types of pterygomaxillary junction (PMJ) during Le-Fort I osteotomy is an important consideration in the reduction of intraoperative complications. The PMJ is known to display population variations and with the recent increase in these surgical interventions in Kenya, a detailed description of the PMJ is warranted. Computed tomography scan images of PMJ obtained from 63 patients were analyzed at the level of the posterior nasal spine to assess types and the morphometry of the PMJ. A fissure type of PMJ was present in 65.9% (83/126 sides) while a synostosis type was present in 34.1% (43/126). Bilateral fissures were found in 58.73% (37/63), bilateral synostosis in 26.98% (17/63), and an asymmetric PMJ in 15.25% (9/63). The average height, width, and thickness of the PMJ were 17.45 ± 5.26 mm, 10.24 ± 1.97 mm, and 6.40 ± 1.97 mm respectively. Males had a significantly greater height (P = 0.003) and width (P = 0.000). The average width was greater in cases with a synostosis as compared with those with a fissure (P = 0.019). Average distance of greater palatine canal was 40.41 ± 2.28 mm and 7.19 ± 2.20 mm from the piriform rim and the pterygoid fossa respectively. The PMJ among Kenyans is characterized by a higher occurrence of synostosis, greater height, and thickness compared with previous findings from other populations. The results of this study can be helpful for surgeons in selecting the most appropriate techniques to achieve successful pterygomaxillary disjunction and minimize avoid attendant complications such as vascular and nerve injuries.

Evaluation of the Proximal Ulna Dorsal Angulation for Ulnar Component Sizing in Elbow Prosthetic Reconstruction After Distal Humeral Resection of Tumor

INTRODUCTION

Elbow prosthetic reconstruction after distal humeral tumor resection is challenging. We identify the value of the proximal ulna dorsal angulation (PUDA) as an easily-measured radiographic parameter that can help inform ulnar component sizing in the Solar Elbow System (SES) and the Modular Universal Tumor and Revision System (MUTARS), two modular prosthetic systems that are commonly used after tumor resection in this anatomic location. We hypothesized that a larger PUDA measurement would require smaller ulnar stems.

METHODS

Demographic data and PUDA measurements were retrospectively reviewed for 514 patients. Multivariate regression was used to determine the effects of patient demographic data on the PUDA. PUDA measurements were collected by three independent reviewers on lateral elbow radiographs. MUTARS and SES templating software was then used to validate the relationship between the PUDA and ulnar stem sizing.

RESULTS

Regression analysis showed no substantial contribution of demographic variables to the PUDA measurement (adjusted R2 = 0.02, F(6, 508) = 2.704, P = 0.01). The MUTARS implant fit 97% of elbows with a PUDA <5° and 91.6% of elbows with PUDA ≥5° (P = 0.26). The largest SES combination fit 100% of elbows with a PUDA ≤10° versus 93% of elbows with a PUDA >10° (P = 0.029). Elbows accommodating the largest SES combination had a smaller median PUDA (5.4° versus 11.7°, P = 0.034); elbows accommodating the MUTARS implant had a smaller median PUDA (5.4° versus 5.8°, P = 0.34).

DISCUSSION

The PUDA is a valuable and easily used preoperative planning tool for prosthetic elbow reconstruction after tumor resection. The proximal ulna dorsal angulation can be easily measured to predict ulnar component fit and reduce intraoperative complications. In patients with a PUDA ≥5°, ulnar component stem fit for current systems may be more challenging.

Osteoporosis in South-East Asian Countries

Osteoporosis (OP) is a condition where there is low bone density and microarchitectural deterioration which can predispose to fragility fractures. There is a wealth of literature on OP from the developed countries, but less so from Asia. This review will explore the field of OP research in South-East Asia with regard to the epidemiology, the diagnosis of OP and the role of laboratory tests in the management of OP, with emphasis on 25-dihydroxyvitamin D and bone turnover markers.

Evolutionary Perspectives on the Developing Skeleton and Implications for Lifelong Health

Osteoporosis is a significant cause of morbidity and mortality in contemporary populations. This common disease of aging results from a state of bone fragility that occurs with low bone mass and loss of bone quality. Osteoporosis is thought to have origins in childhood. During growth and development, there are rapid gains in bone dimensions, mass, and strength. Peak bone mass is attained in young adulthood, well after the cessation of linear growth, and is a major determinant of osteoporosis later in life. Here we discuss the evolutionary implications of osteoporosis as a disease with developmental origins that is shaped by the interaction among genes, behavior, health status, and the environment during the attainment of peak bone mass. Studies of contemporary populations show that growth, body composition, sexual maturation, physical activity, nutritional status, and dietary intake are determinants of childhood bone accretion, and provide context for interpreting bone strength and osteoporosis in skeletal populations. Studies of skeletal populations demonstrate the role of subsistence strategies, social context, and occupation in the development of skeletal strength. Comparisons of contemporary living populations and archeological skeletal populations suggest declines in bone density and strength that have been occurring since the Pleistocene. Aspects of western lifestyles carry implications for optimal peak bone mass attainment and lifelong skeletal health, from increased longevity to circumstances during development such as obesity and sedentism. In light of these considerations, osteoporosis is a disease of contemporary human evolution and evolutionary perspectives provide a key lens for interpreting the changing global patterns of osteoporosis in human health.

Evolutionary Origins of the Differences in Osteoporosis Risk in US Populations

Over the past 50 years, it has been increasingly evident that there are population differences in bone mass and the risk of osteoporosis. In the United States, many studies have reported a lower prevalence of osteoporosis in African Americans compared with people of European descent. If we trace the trajectory of changes in lifeways from the earliest migrations of early Homo out of Africa over the past two million years or so, to include lower vitamin D levels in higher latitudes; more meat in the diet; increasing sedentism; and a longer lifespan/longer postmenopausal period, it is not surprising that osteoporosis occurs more frequently in populations of European descent. While many scholars have explored the apparent "paradox" of higher bone mass, lower vitamin D levels, and higher parathyroid hormone levels among African Americans, this brief review of evolutionary shifts that affected our species may change the approach to understanding the current population differences in the United States.

The Relationship between Risk Factors for Metabolic Syndrome and Bone Mineral Density in Menopausal Korean Women

BACKGROUND

The risk factors of metabolic syndrome (MetS) in menopausal women are potential causes of osteoporosis. However, there is no consensus on this. We aimed to determine the relationship between risk factors of MetS and bone mineral density (BMD) in menopausal Korean women.

METHODS

We enrolled 205 menopausal Korean women who visited a health promotion center in Seoul in 2015 and divided them into the following two groups according to the National Cholesterol Education Program-Adult Treatment Panel III (NCEP-ATP III) criteria with modified waist-circumference criteria: the non-MetS group (Group 1, n=90) and the MetS group (Group 2, n=115). Anthropometric parameters and clinical parameters, including blood pressure, blood lipid profile (cholesterol, triglycerides), and fasting blood sugar levels were recorded for all participants. BMD at the lumbar spine was determined using dual-energy X-ray absorptiometry (DEXA). The relationship between the risk factors of MetS and bone mineral density was analyzed by statistical methods.

RESULTS

There was no significant difference in risk factors of MetS between the groups. In correlation tests, waist circumference showed a significant association with body surface area (BSA) (r = -0.242, P < 0.001). Diastolic blood pressure was correlated with BSA (r = 0.186, P < 0.01) and bone mineral content (BMC) (r = 0.161, P < 0.05). However, multiple regression analysis showed no significant relationship between MetS risk factors and BMD.

CONCLUSION

The risk factors of MetS did not affect BMD in menopausal Korean women. Follow-up studies with a larger study population are necessary size to allow the investigation of other research variables.

Review of the Literature Examining the Association of Serum Uric Acid with Osteoporosis and Mechanistic Insights into Its Effect on Bone Metabolism

Background And Objective:

Osteoporosis is a common bone disorder that increases susceptibility to fragility bone fractures. The clinical and public health repercussions of osteoporosis are huge due to the morbidity, mortality, and cost of medical care linked with fragility fractures. Clinical assessment of osteoporotic risk factors can help to identify candidates at an early stage that will benefit from medical intervention and potentially lowering the morbidity and mortality seen with fractures and complications. Given this, research is ongoing to evaluate the association of osteoporosis with some novel or less well-studied risk factors/bio-markers such as uric acid (UA).

Discussion:

Uric acid’s antioxidant activity has been proposed to be one of the factors responsible for increasing longevity and lowering rates of age-related cancers during primate evolution, the level of which increased markedly due to loss of uricase enzyme activity (mutational silencing). Accumulated evidence shows that oxidative stress is the fundamental mechanism of age-related bone loss and acts via enhancing osteoclastic activity and increasing bone resorption. Antioxidant substances such as ascorbic acid scavenge free radicals are positively related to bone health. Thus, it is hypothesized that uric acid holds bone-protective potential owing to its potent antioxidative property. Several correlation studies have been conducted globally to investigate the relationship between serum uric acid with bone mineral density and osteoporosis. Few pre-clinical studies have tried to investigate the interaction between uric acid and bone mineral density and reported important role played via Runt-related transcription factor 2 (RUNX2)/core-binding factor subunit alpha-1 (CBF-alpha-1), Wingless-related integration site (Wnt)-3a/β-catenin signaling pathway and 11β Hydroxysteroid Dehydrogenase type 1.

Conclusion:

In this review, the authors provided a comprehensive summary of the literature related to association studies reported in humans as well work done until date to understand the potential cellular and molecular mechanisms that interplay between uric acid and bone metabolism.

Efficacy and Safety of Tenofovir Disoproxil Fumarate Versus Low-Dose Stavudine Over 96 Weeks: A Multicountry Randomized, Noninferiority Trial

BACKGROUND

Reducing doses of antiretroviral drugs, including stavudine (d4T), may lower toxicity, while preserving efficacy. There are substantial concerns about renal and bone toxicities of tenofovir disoproxil fumarate (TDF).

SETTING

HIV-1-infected treatment-naive adults in India, South Africa, and Uganda.

METHODS

A phase-4, 96-week, randomized, double-blind, noninferiority trial compared d4T 20 mg twice daily and TDF, taken in combination with lamivudine (3TC) and efavirenz (EFV). The primary endpoint was the proportion of participants with HIV-1 RNA <50 copies per milliliter at 48 weeks. Adverse events assessments included measures of bone density and body fat. The trial is registered on Clinicaltrials.gov (NCT02670772).

RESULTS

Between 2012 and 2014, 536 participants were recruited per arm. At week 96, trial completion rates were 75.7% with d4T/3TC/EFV (n = 406) and 82.1% with TDF/3TC/EFV (n = 440, P = 0.011). Noncompletion was largely due to virological failure [6.2% (33) with d4T/3TC/EFV versus 5.4% (29) with TDF/3TC/EFV; P = 0.60]. For the primary endpoint, d4T/3TC/EFV was noninferior to TDF/3TC/EFV (79.3%, 425/536 versus 80.8% 433/536; difference = -1.49%, 95% CI: -6.3 to 3.3; P < 0.001). Drug-related adverse event discontinuations were higher with d4T (6.7%, 36), than TDF (1.1%, 6; P < 0.001). Lipodystrophy was more common with d4T (5.6%, 30) than TDF (0.2%, 1; P < 0.001). Creatinine clearance increased in both arms, by 18.1 mL/min in the d4T arm and 14.2 mL/min with TDF (P = 0.03). Hip bone density measures, however, showed greater loss with TDF.

CONCLUSIONS

Low-dose d4T combined with 3TC/EFV demonstrated noninferior virological efficacy compared with TDF/3TC/EFV, but mitochondrial toxicity remained high. Little renal toxicity occurred in either arm. Implications of bone mineral density changes with TDF warrant investigation.

A dietary pattern rich in calcium, potassium, and protein is associated with tibia bone mineral content and strength in young adults entering initial military training

Background

Stress fracture risk is elevated during initial military training (IMT), particularly in lower-extremity bones such as the tibia. Although the etiology of stress fractures is multifactorial, lower bone strength increases risk.

Objective

The objective of this study was to assess, through the use of peripheral quantitative computed tomography, whether adherence to a dietary pattern rich in calcium, potassium, and protein before IMT is positively associated with bone indexes in young adults entering IMT.

Design

A cross-sectional analysis was performed with the use of baseline data from 3 randomized controlled trials in Army, Air Force, and Marine recruits (n = 401; 179 men, 222 women). Dietary intake was estimated from a food-frequency questionnaire. A dietary pattern characterized by calcium, potassium, and protein was derived via reduced rank regression and a pattern z score was computed for each volunteer, where higher scores indicated greater adherence to the pattern. At the 4% (metaphysis) and 14% (diaphysis) sites of the tibia, bone mineral content (BMC), volumetric bone mineral density, robustness, and strength indexes were evaluated. Associations between dietary pattern z score as the predictor variable and bone indexes as the response variables were evaluated by multiple linear regression.

Results

Pattern z score was positively associated with BMC (P = 0.004) and strength (P = 0.01) at the metaphysis and with BMC (P = 0.0002), strength (P = 0.0006), and robustness (P = 0.02) at the diaphysis when controlling for age, sex, race, energy, smoking, education, and exercise. Further adjustment for BMI attenuated the associations, except with diaphyseal BMC (P = 0.005) and strength (P = 0.01). When height and weight were used in place of body mass index, the association with BMC remained (P = 0.046).

Conclusions

A dietary pattern rich in calcium, potassium, and protein is positively associated with measures of tibia BMC and strength in recruits entering IMT. Whether adherence to this dietary pattern before IMT affects injury susceptibility during training remains to be determined. These trials were registered at clinicaltrials.gov as NCT01617109 and NCT02636348.

The Association of Thyroid Function With Bone Density During Childhood

CONTEXT

Although the skeleton is a well-known thyroid hormone target organ, very little data are available on the association of thyroid function with bone outcomes during childhood.

OBJECTIVE

To study the association of thyroid function with bone mass during childhood.

DESIGN, SETTING, AND PARTICIPANTS

Population-based prospective cohort including 4204 children with TSH and free T4 (FT4) measured at the age of 6 years.

MAIN OUTCOME MEASURES

Bone density was assessed by a total body dual-energy X-ray absorptiometry scan at the median age of 6 years (95% range, 5.6 to 7.9) and at the age of 10 years (95% range, 9.0 to 10.9) in 4204 and 3404 participants, respectively.

RESULTS

There was an inverse association of TSH with bone mineral density (BMD) at the age of 6 (β -0.028 ± 0.011, P = 0.009) and with follow-up measurements at the age of 10 (β -0.027 ± 0.011, P = 0.014), but not with bone mineral content (BMC) at the age of 6 (β -0.028 ± 0.015, P = 0.06) or for follow-up measurements of BMC at the age of 10 (β -0.011 ± 0.015, P = 0.47). There was an inverse association of FT4 with BMD (β -0.016 ± 0.006, P = 0.014) and BMC (β -0.023 ± 0.009, P = 0.009) cross-sectionally, and also at the age of 10 years (BMD: β -0.018 ± 0.007, P = 0.007; BMC: β -0.021 ± 0.009, P = 0.020).

CONCLUSION

A higher FT4 concentration is associated with lower bone mass at the age of 6 and at the age of 10 years. These data provide insights into the effects of thyroid function on bone physiology during childhood.

The prevalence of sarcopenia and relationships between muscle and bone in ageing West-African Gambian men and women

BACKGROUND

The rapidly rising ageing population in low and middle-income countries (LMIC) will lead to a concurrent increase in musculoskeletal diseases. Sarcopenia is a disease caused by progressive loss of skeletal muscle mass and strength, leading to adverse outcomes including frailty, falls, fractures, and premature mortality. We investigated the prevalence of sarcopenia, assessed the suitability of current diagnostic guidelines and explored muscle-bone relationships in ageing men and women from rural Gambia.

METHODS

A total of 249 women and 239 men aged 40-75+ years were recruited. Body composition was measured using dual energy X-ray absorptiometry. Comparisons of the Foundations for the National Institutes of Health (FNIH) and European Working Group On Sarcopenia (EWGSOP) definitions of sarcopenia to define prevalence and to identify poor physical capability were determined. Functional ability was assessed by jumping mechanography to calculate lower limb muscle force and power; grip strength was assessed by a hand dynamometer. Peripheral quantitative computed tomography was used to assess muscle-bone relationships.

RESULTS

The prevalence of sarcopenia in Gambian men and women significantly varied depending on the definition used; in men 20% and 19% and in women 45% and 10% for FNIH and EWGSOP, respectively. The FNIH appendicular lean mass cut-off had greatest sensitivity and specificity in identifying low functional ability in Gambian adults. Muscle force was positively associated with measures of tibial bone size, strength, and mineral content.

CONCLUSIONS

The variation in the prevalence of sarcopenia depends on the definition used and highlights the importance of measuring functional capability across ethnic populations.

Reference values for muscle strength: a systematic review with a descriptive meta-analysis

BACKGROUND

Muscle strength is an important component of health.

OBJECTIVE

To describe and evaluate the studies which have established the reference values for muscle strength on healthy individuals and to synthesize these values with a descriptive meta-analysis approach.

METHODS

A systematic review was performed in MEDLINE, LILACS, and SciELO databases. Studies that investigated the reference values for muscle strength of two or more appendicular/axial muscle groups of health individuals were included. Methodological quality, including risk of bias was assessed by the QUADAS-2. Data extracted included: country of the study, sample size, population characteristics, equipment/method used, and muscle groups evaluated.

RESULTS

Of the 414 studies identified, 46 were included. Most of the studies had adequate methodological quality. Included studies evaluated: appendicular (80.4%) and axial (36.9%) muscles; adults (78.3%), elderly (58.7%), adolescents (43.5%), children (23.9%); isometric (91.3%) and isokinetic (17.4%) strength. Six studies (13%) with similar procedures were synthesized with meta-analysis. Generally, the coefficient of variation values that resulted from the meta-analysis ranged from 20.1% to 30% and were similar to those reported by the original studies. The meta-analysis synthesized the reference values of isometric strength of 14 muscle groups of the dominant/non-dominant sides of the upper/lower limbs of adults/elderly from developed countries, using dynamometers/myometer.

CONCLUSIONS

Most of the included studies had adequate methodological quality. The meta-analysis provided reference values for the isometric strength of 14 appendicular muscle groups of the dominant/non-dominant sides, measured with dynamometers/myometers, of men/women, of adults/elderly. These data may be used to interpret the results of the evaluations and establish appropriate treatment goals.

Musculoskeletal health of Indigenous Australians

INTRODUCTION

Research on non-communicable diseases (NCD) in Indigenous Australians has mostly focused on diabetes mellitus and chronic kidney or cardiovascular disease. Osteoporosis, characterised by low bone mass and structural deterioration of bone tissue, and sarcopenia, the age-related loss of muscle mass and strength, often co-exist with these common NCDs-the combination of which will disproportionately increase bone fragility and fracture risk and negatively influence cortical and trabecular bone. Furthermore, the social gradient of NCDs, including osteoporosis and fracture, is well-documented, meaning that specific population groups are likely to be at greater risk of poorer health outcomes: Indigenous Australians are one such group.

PURPOSE

This review summarises the findings reported in the literature regarding the muscle and bone health of Indigenous Australians.

FINDINGS

There are limited data regarding the musculoskeletal health of Indigenous Australians; however, areal bone mineral density (aBMD) measured by dual-energy X-ray absorptiometry (DXA) is reported to be greater at the hip compared to non-Indigenous Australians. Falls are the leading cause of injury-related hospitalisations in older Australians, particularly Indigenous Australians, with a great proportion suffering from fall-related fractures. Despite sparse data, it appears that Indigenous men and women have a substantially higher risk of hip fracture at a much younger age compared to non-Indigenous Australians.

CONCLUSION

Data on more detailed musculoskeletal health outcomes are required in Indigenous Australians to better understand fracture risk and to formulate evidence-based strategies for fracture prevention and to minimise the risk of falls.

Prevalence of osteoporosis and osteopenia in an apparently healthy Indian population - a cross-sectional retrospective study

OBJECTIVES

An understanding of bone mineral density (BMD) pattern in a population is crucial for prevention and diagnosis of osteoporosis and management of its complications in later life. This study aimed to screen the bone health status and factors associated with osteoporosis in an apparently healthy Indian population.

METHODS

A retrospective review of medical records was done in a tertiary-care hospital for the subjects who had undergone preventive health-check-ups that included BMD measurements at femur-neck, total-femur, and lumbar-spine.

RESULTS

We evaluated 524 subjects (age, 50.0 ± 12.4 years) including 41.2% female and 58.8% male subjects. Osteoporosis was present in 6.9% subjects (female, 11.1%; male, 4.2%) and osteopenia in 34% subjects (female, 40.3%; male, 29.9%). Absolute BMD was higher in male subjects (P < 0.001) compared to female subjects at all bone sites. Prevalence of osteoporosis increased with age in female subjects, but not in male subjects. Osteoporosis rates in the age-groups of 30-39, 40-49, 50-59, 60-69, and ≥70 years were 3%, 3.4%, 14.3%, 18.6%, and 36.4%, respectively in female subjects while prevalence in male subjects was 0%, 4%, 6.5%, 4.3%, and 5.6%, respectively, at lumbar spine. Height (r = 0.234-0.358), weight (r = 0.305-0.388), body mass index (r = 0.143-0.285) and physical activity (r = 0.136-0.153) were positively; and alkaline phosphatase (r = -0.133 to -0.203) was negatively correlated with BMD (all P < 0.01) at all sites. These parameters retained significant correlation after controlling for age and sex. No correlation of serum 25-hydroxy-vitamin-D and calcium was noted with BMD (P > 0.05) at any site.

CONCLUSIONS

Further data on absolute BMD, T scores, and prevalence rates of osteoporosis/osteopenia on multiple bone sites have been presented in this article.

Dairy products and bone health: how strong is the scientific evidence?

The relevance of dairy produce for the diminishment of osteoporotic risk is still a matter of scientific debate due to the outcome of a few single observational studies. This review will address the most robust point estimate on the role of dairy products, as reported in systematic reviews and meta-analyses on randomised controlled trials in the case of bone mineralisation or prospective studies in the case of fracture risk. Plain dairy products or those fortified with Ca and/or vitamin D improve total body bone mineral content (BMC) by 45-50 g over 1 year when the daily baseline Ca intake is lower than 750 mg in Caucasians and Chinese girls. In Caucasian and Chinese women, Ca from (fortified) dairy products increases bone mineral density (BMD) by 0·7-1·8 % over 2 years dependent on the site of measurement. Despite the results on BMC, there are currently no studies that have investigated the potential of dairy products to reduce fracture risk in children. In adult Caucasian women, daily intake of 200-250 ml of milk is associated with a reduction in fracture risk of 5 % or higher. In conclusion, the role of dairy products for BMC or BMD has been sufficiently established in Chinese and Caucasian girls and women. In Caucasian women, drinking milk also reduces fracture risk. More research on the role of dairy products within the context of bone health-promoting diets is needed in specific ethnicities, other than Chinese and Caucasians, and in men.

Raised serum uric acid is associated with higher bone mineral density in a cross-sectional study of a healthy Indian population

Purpose

Oxidative stress has been implicated as a fundamental mechanism in the decline of bone mass. Reactive oxygen species are reported to suppress osteoblast generation and differentiation and enhance osteoclast development and activity. Increasing evidence suggests favorable effect of serum uric acid (UA) on bone metabolism due to its antioxidant properties. Therefore, we investigated the association between serum UA levels and bone mineral density (BMD) in healthy adult Indian subjects.

Materials and methods

We reviewed the medical records of 524 subjects who had undergone preventive health check-ups in a tertiary care hospital that included UA and BMD measurements at femur neck, total femur, and lumbar spine. Subjects concomitantly taking drugs or having a medical condition that would affect the bone metabolism or UA levels were excluded.

Results

The final analysis included 310 subjects (mean age: 47.2±12.2 years; females: 43.5%; males: 56.5%). Study population was categorized into two groups based on the group median value for UA (ie, 5.4 mg/dL). BMD was significantly higher at all skeletal sites in subjects with UA >5.4 mg/dL compared to subjects with UA ≤5.4 mg/dL (p<0.001). On correlation analysis, UA was positively associated with BMD at all skeletal sites (r=0.211–0.277; p<0.05). The correlation remained significant after controlling for age (p<0.05) and lifestyle factors (smoking, alcohol use, physical activity, and diet; p<0.05) independently. UA significantly (p<0.001) accounted for 4.5%–7.7% of the variance in BMD (r²=0.045–0.077) in unadjusted model and 1.6%–3.2% of the variance (p<0.05) when adjusted for age and body mass index combined at lumbar spine and right femur neck, respectively.

Conclusion

We conclude that raised UA levels are associated with higher BMD at all skeletal sites and UA may have a protective role in bone metabolism owing to its antioxidant effect.

Bone mass, microarchitecture and strength are influenced by race/ethnicity in young adult men and women

Lower rates of fracture in both Blacks compared to Whites, and men compared to women are not completely explained by differences in bone mineral density (BMD). Prior evidence suggests that more favorable cortical bone microarchitecture may contribute to reduced fracture rates in older Black compared to White women, however it is not known whether these differences are established in young adulthood or develop during aging. Moreover, prior studies using high-resolution pQCT (HR-pQCT) have reported outcomes from a fixed-scan location, which may confound sex- and race/ethnicity-related differences in bone structure.

PURPOSE

We determined differences in bone mass, microarchitecture and strength between young adult Black and White men and women.

METHODS

We enrolled 185 young adult (24.2±3.4yrs) women (n=51 Black, n=50 White) and men (n=34 Black, n=50 White) in this cross-sectional study. We used dual-energy X-ray absorptiometry (DXA) to determine areal BMD (aBMD) at the femoral neck (FN), total hip (TH) and lumbar spine (LS), as well as HR-pQCT to assess bone microarchitecture and failure load by micro-finite element analysis (μFEA) at the distal tibia (4% of tibial length). We used two-way ANOVA to compare bone outcomes, adjusted for age, height, weight and physical activity.

RESULTS

The effect of race/ethnicity on bone outcomes did not differ by sex, and the effect of sex on bone outcomes did not differ by race/ethnicty. After adjusting for covariates, Blacks had significantly greater FN, TH and LS aBMD compared to Whites (p<0.05 for all). Blacks also had greater cortical area, vBMD, and thickness, and lower cortical porosity, with greater trabecular thickness and total vBMD compared to Whites. μFEA-estimated FL was significantly higher among Blacks compared to Whites. Men had significantly greater total vBMD, trabecular thickness and cortical area and thickness, but greater cortical porosity than women, the net effects being a higher failure load in men than women.

CONCLUSION

These findings demonstrate that more favorable bone microarchitecture in Blacks compared to Whites and in men compared to women is established by young adulthood. Advantageous bone strength among Blacks and men likely contributes to their lower risk of fractures throughout life compared to their White and women counterparts.

Associations of muscle force, power, cross-sectional muscle area and bone geometry in older UK men

BACKGROUND

Ageing is associated with sarcopenia, osteoporosis, and increased fall risk, all of which contribute to increased fracture risk. Mechanically, bone strength adapts in response to forces created by muscle contractions. Adaptations can be through changes in bone size, geometry, and bending strength. Muscle mass is often used as a surrogate for muscle force; however, force can be increased without changes in muscle mass. Increased fall risk with ageing has been associated with a decline in muscle power-which is a measure of mobility. The aims of this study were as follows: (i) to investigate the relationship between muscle parameters in the upper and lower limbs with age in UK men and the influence of ethnicity on these relationships; (ii) to examine the relationships between jump force/grip strength/cross-sectional muscle area (CSMA) with bone outcomes at the radius and tibia.

METHODS

White European, Black Afro-Caribbean, and South Asian men aged 40-79 years were recruited from Manchester, UK. Cortical bone mineral content, cross-sectional area, cortical area, cross-sectional moment of inertia, and CSMA were measured at the diaphysis of the radius and tibia using peripheral quantitative computed tomography. Lower limb jump force and power were measured from a single two-legged jump performed on a ground-reaction force platform. Grip strength was measured using a dynamometer. Associations between muscle and bone outcomes was determined using linear regression with adjustments for age, height, weight, and ethnicity.

RESULTS

Three hundred and one men were recruited. Jump force was negatively associated with age; for every 10 year increase in age, there was a 4% reduction in jump force (P < 0.0001). There was a significant age-ethnicity interaction for jump power (P = 0.039); after adjustments, this was attenuated (P = 0.088). For every 10 year increase in age, grip strength decreased by 11%. Jump force was positively associated with tibial bone outcomes: a 1 standard deviation greater jump force was associated with significantly higher cortical bone mineral content 3.1%, cross-sectional area 4.2%, cortical area 3.4%, and cross-sectional moment of inertia 6.8% (all P < 0.001). Cross-sectional muscle area of the lower leg was not associated with tibial bone outcomes. Both grip strength and CSMA of the arm were positively associated, to a similar extent, with radius diaphyseal bone outcomes.

CONCLUSIONS

Jump force and power are negatively associated with age in UK men. In the lower limb, the measurement of jump force is more strongly related to bone outcomes than CSMA. It is important to consider jump force and power when understanding the aetiology of bone loss and mobility in ageing men.