Genetic and environmental determinants of peak bone mass in young men and women

Subsequent fracture risk in Norwegians and immigrants with an index forearm fracture: a cohort study

The current study investigated subsequent fracture risk following a forearm fracture in three country of birth categories: Norway, Europe and North America, and other countries. Subsequent fracture risk was modestly higher in Norwegian-born individuals compared to the two other groups. Secondary fracture prevention should be recommended regardless of country background.

BACKGROUND

Fracture risk is higher in patients with a previous fracture, but whether subsequent fracture risk differs by origin of birth is unknown. This study explores subsequent fracture risk in patients with an index forearm fracture according to region of birth.

METHODS

Nationwide data on forearm fractures in patients ≥ 18 years in 2008-2019 were obtained from the Norwegian Patient Registry and Statistics Norway. Index fractures were identified by ICD-10 code S52, whereas subsequent fractures included any ICD-10 fracture code. Data on country of birth were from Statistics Norway and included three regional categories: (1) Norway, (2) other Europe and North America and (3) other countries. Direct age standardization and Cox proportional hazard regression were used to analyse the data.

RESULTS

Among 143,476 individuals with an index forearm fracture, 35,361 sustained a subsequent fracture. Norwegian-born forearm fracture patients had the highest subsequent fracture rates (516/10,000 person-years in women and 380 in men). People born outside Europe and North America had the lowest rates (278/10,000 person-years in women and 286 in men). Compared to Norwegian-born individuals, the hazard ratios (HRs) of subsequent fracture in individuals from Europe and North American were 0.93 (95% CI 0.88-0.98) in women and 0.85 (95% CI 0.79-0.92) in men. The corresponding HRs in individuals from other countries were 0.76 (95% CI 0.70-0.84) in women and 0.82 (95% CI 0.74-0.92) in men.

CONCLUSION

Individuals born outside Norway had a lower subsequent fracture risk than Norwegian-born individuals; however, subsequent fracture risk increased with age in all groups. Our results indicate that secondary fracture prevention should be recommended regardless of region of origin.

Osteoporosis and fracture risk are multifactorial in patients with inflammatory rheumatic diseases

Patients with inflammatory rheumatic and musculoskeletal diseases (iRMDs) such as rheumatoid arthritis, connective tissue diseases, vasculitides and spondyloarthropathies are at a higher risk of osteoporosis and fractures than are individuals without iRMDs. Research and management recommendations for osteoporosis in iRMDs often focus on glucocorticoids as the most relevant risk factor, but they largely ignore disease-related and general risk factors. However, the aetiopathogenesis of osteoporosis in iRMDs has many facets, including the negative effects on bone health of local and systemic inflammation owing to disease activity, other iRMD-specific risk factors such as disability or malnutrition (for example, malabsorption in systemic sclerosis), and general risk factors such as older age and hormonal loss resulting from menopause. Moreover, factors that can reduce fracture risk, such as physical activity, healthy nutrition, vitamin D supplementation and adequate treatment of inflammation, are variably present in patients with iRMDs. Evidence relating to general and iRMD-specific protective and risk factors for osteoporosis indicate that the established and very often used term 'glucocorticoid-induced osteoporosis' oversimplifies the complex inter-relationships encountered in patients with iRMDs. Osteoporosis in these patients should instead be described as 'multifactorial'. Consequently, a multimodal approach to the management of osteoporosis is required. This approach should include optimal control of disease activity, minimization of glucocorticoids, anti-osteoporotic drug treatment, advice on physical activity and nutrition, and prevention of falls, as well as the management of other risk and protective factors, thereby improving the bone health of these patients.

Hormonal Control of Bone Architecture Throughout the Lifespan: Implications for Fracture Prediction and Prevention

BACKGROUND

Skeletal modeling in childhood and adolescence and continuous remodeling throughout the lifespan are designed to adapt to a changing environment and resist external forces and fractures. The flux of sex steroids in men and women, beginning from fetal development and evolving through infancy, childhood, puberty, young adulthood, peri/menopause transition, and postmenopause, is critical for bone size, peak bone mass, and fracture resistance.

OBJECTIVE

This review will highlight how changes in sex steroids throughout the lifespan affect bone cells and the consequence of these changes on bone architecture and strength.

METHODS

Literature review and discussion.

RESULTS

The contributions of estrogen and testosterone on skeletal development have been difficult to study due to the reciprocal and intertwining contributions of one on the other. Although orchiectomy in men renders circulating testosterone absent, circulating estrogen also declines due to testosterone being the substrate for estradiol. The discovery of men with absent estradiol or resistance to estrogen and the study of mouse models led to the understanding that estrogen has a larger direct role in skeletal development and maintenance in men and women. The mechanistic reason for larger bone size in men is incompletely understood but related to indirect effects of testosterone on the skeleton, such as higher muscle mass leading to larger mechanical loading. Declines in sex steroids during menopause in women and androgen deprivation therapies in men have profound and negative effects on the skeleton. Therapies to prevent such bone loss are available, but how such therapies can be tailored based on bone size and architecture remains an area of investigation.

CONCLUSION

In this review, the elegant interplay and contribution of sex steroids on bone architecture in men and women throughout the lifespan is described.

Single-Cell Integration of BMD GWAS Results Prioritize Candidate Genes Influencing Age-Related Bone Loss

The regulation of bone mineral density (BMD) is highly influenced by genetics and age. Although genome-wide association studies (GWAS) for BMD have uncovered many genes through their proximity to associated variants (variant nearest-neighbor [VNN] genes), the cell-specific mechanisms of each VNN gene remain unclear. This is primarily due to the inability to prioritize these genes by cell type and age-related expression. Using age-related transcriptomics, we found that the expression of many VNN genes was upregulated in the bone and marrow from aged mice. Candidate genes from GWAS were investigated using single-cell RNA-sequencing (scRNA-seq) datasets to enrich for cell-specific expression signatures. VNN candidate genes are highly enriched in osteo-lineage cells, osteocytes, hypertrophic chondrocytes, and Lepr+ mesenchymal stem cells. These data were used to generate a "blueprint" for Cre-loxp mouse line selection for functional validation of candidate genes and further investigation of their role in BMD maintenance throughout aging. In VNN-gene-enriched cells, Sparc, encoding the extracellular matrix (ECM) protein osteonectin, was robustly expressed. This, along with expression of numerous other ECM genes, indicates that many VNN genes likely have roles in ECM deposition by osteoblasts. Overall, we provide data supporting streamlined translation of GWAS candidate genes to potential novel therapeutic targets for the treatment of osteoporosis. © 2023 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Bone mass in Saudi women aged 20-40 years: the association with obesity and vitamin D deficiency

This study describes that low bone density is prevalent in premenopausal Saudi women, especially women of normal weight and vitamin D deficiency. Although BMD is higher in obese young women, this may not be beneficial later in life in conjunction with persistent vitamin D deficiency.

INTRODUCTION

Not attaining peak bone mass is one crucial factor contributing to the risk of developing osteoporosis and suffering fractures in later life. The objectives of this study were to describe the normal range of bone mineral density (BMD) and bone mineral content (BMC) in premenopausal Saudi women in relation to obesity and vitamin D insufficiency.

METHODS

A cross-sectional study involving 312 healthy Saudi women aged 20-40. All women were clinically examined. BMD (g/cm²) and BMC (g) assessed at total body (TB), femoral neck (FN) and lumbar spine (LS) were performed using dual-energy X-ray absorptiometry (DXA). Obesity was defined as BMI ≥ 30 kg/m² and vitamin D deficiency defined as 25(OH)D < 50 nmol/L.

RESULTS

Almost half of the studied women were obese, and the majority (86.2%) were deficient in vitamin D. Mean BMD in TB 1.060 ± 0.091, FN 0.918 ± 0.153 and LS 1.118 ± 0.123 g/cm², while TB-BMC 2077 ± 272 g. When classified by BMI, the proportion with low bone density was 2-3 times higher among the normal weight compared to the obese women, p < 0.001. In the cohort overall, ~ 19% of these young premenopausal women had osteopenia or osteoporosis at the femoral neck, but 26% in normal weight, vitamin D deficient women.

CONCLUSION

This study shows low bone density in premenopausal Saudi women, particularly those with normal weight. While obesity appears to confer some protection against vitamin D deficiency at this age, this is assumed to change in later life.

Between-subject and within-subject variability in measures of biochemical markers of bone turnover in cynomolgus and rhesus macaques

Development of optimal bone mass during early adulthood is determined by the balance between bone formation and resorption. The utility of minimally invasive biomarkers for monitoring bone turnover balance in maturing non-human primates has received limited attention. This study evaluated the biological variation of osteocalcin (a marker of bone formation), carboxyterminal cross-linking telopeptide of type 1 collagen (CTX, a marker of bone resorption), and the ratio of osteocalcin to CTX (reflecting bone turnover balance), in 136 rhesus and cynomolgus macaques aged 3.8-11.6 years. In a subsample of the animals (n = 28), blood samples were collected at monthly intervals over 4 months. Between-subject analysis revealed that there were no sex or species differences for CTX. Osteocalcin and the ratio of osteocalcin to CTX were higher in males than in females, and in rhesus macaques than in cynomolgus macaques. There were no changes in osteocalcin, CTX, or the ratio of osteocalcin to CTX across 4 months for any of the groups. In contrast, there was considerable within-subject variation in osteocalcin and CTX concentrations. However, differences in values exhibited no discernible pattern, suggesting that within-subject variation can be reduced by averaging repeat measurements. In summary, the data provide reference values for male and female rhesus and cynomolgus macaques and support the utility of osteocalcin and CTX as biomarkers to monitor bone turnover at the population level.

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

CONTEXT

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Milk and Dairy Products: Good or Bad for Human Bone? Practical Dietary Recommendations for the Prevention and Management of Osteoporosis

Osteoporosis affects women twice as often as men. Additionally, it is estimated that 0.3 million and 1.7 million people have hip fractures in the USA and Europe, respectively. Having a proper peak bone mass and keeping it as long as possible is especially important for osteoporosis prevention. One of the most important calcium sources is milk and dairy products. Breast milk is the best infant food, but milk should not be avoided later in life to prevent losing bone mass. On the other hand, more and more people limit their milk consumption and consume other dairy or non-dairy products. For example, they are usually replaced with plant beverages, which should be consumed carefully in several age groups. Additionally, an important element of milk and dairy products, as well as plant beverages, are probiotics and prebiotics, which may modulate bone turnover. Dietary recommendations focused on milk, and dairy products are an important element for the prevention of osteoporosis.

Lean mass and peak bone mineral density

Objectives

The association between body composition parameters and peak bone mineral density is not well documented. The aim of this study is to assess the relative contributions of lean mass and fat mass on peak bone mineral density (BMD).

Methods

The study involved 416 women and 334 men aged between 20 and 30 years who were participants in the population-based Vietnam Osteoporosis Study. Whole body composition parameters (eg, fat mass and lean mass) and BMD at the lumbar spine and femoral neck were measured by dual-energy X-ray absorptiometry. The association between lean mass and fat mass and BMD was analyzed by the linear regression model using the Least Absolute Shrinkage and Selection Operator (LASSO).

Results

Peak BMD in men was higher than women, and the difference was more pronounced at the femoral neck (average difference: 0.123 g/cm²; 95% confidence interval [CI] 0.105–0.141 g/cm²) than at the lumbar spine (average difference 0.019 g/cm²; 95% CI, 0.005–0.036 g/cm²). Results of LASSO regression indicated that lean mass was the only predictor of BMD for either men or women. Each kilogram increase in lean mass was associated with ∼0.01 g/cm² increase in BMD. Lean mass alone explained 16% and 36% of variation in lumbar spine and femoral neck BMD, respectively.

Conclusions

Lean mass, not fat mass, is the main determinant of peak bone mineral density. This finding implies that good physical activity during adulthood can contribute to the maximization of peak bone mass during adulthood.

Adherence to the dietary approaches to stop hypertension (DASH) dietary pattern and osteoporosis risk in postmenopausal Iranian women

This is the first study to examine the association of adherence to the dietary approaches to stop hypertension (DASH) dietary pattern and osteoporosis risk in postmenopausal Iranian women. Findings suggest the inverse association of adherence to the DASH dietary pattern and osteoporosis risk in postmenopausal Iranian women.

INTRODUCTION

This study was aimed to examine the association of adherence to the dietary approaches to stop hypertension (DASH) dietary pattern and osteoporosis risk in postmenopausal Iranian women, hypothesizing that higher adherence to this pattern is associated with lower risk of postmenopausal osteoporosis.

METHODS

One hundred fifty-one postmenopausal Iranian women aged 50-85 years participated in this cross-sectional study. Lumbar spine and femoral neck bone mineral densities (BMDs) were measured via dual-energy X-ray absorptiometry. Postmenopausal osteoporosis was then defined using the WHO criteria as a BMD T-score of ≤ - 2.5 standard deviations. The usual past-year dietary intakes were assessed by a valid and reliable 168-item food frequency questionnaire. The DASH score was then calculated based on energy-adjusted intakes of eight major dietary components usually emphasized (i.e., fruits, vegetables, nuts and legumes, low-fat dairy products, and whole grains) or minimized (i.e., sodium, sweets, and red or processed meats) in the DASH diet. The higher the DASH score of a participant, the higher the adherence to the DASH dietary pattern.

RESULTS

After adjusting for several potential covariates in the multivariable-adjusted binary logistic regression analysis, participants in the highest tertile of DASH score had lower risk of osteoporosis at lumbar spine than those in the lowest tertile (odds ratio = 0.28; 95% confidence interval, 0.09-0.88; p = 0.029). However, no significant association was observed between adherence to the DASH dietary pattern and risk of osteoporosis at femoral neck.

CONCLUSION

Findings suggest the inverse association of adherence to the DASH dietary pattern and osteoporosis risk in postmenopausal Iranian women.

Healthy eating index-2015 and bone mineral density among adult Iranian women

This is the first study to examine the potential association of adherence to the healthy eating index-2015 (HEI-2015) and bone health. Findings suggest that better diet quality (i.e., a higher HEI-2015 score) is significantly associated with a small but clinically important increase in bone mineral density among adult Iranian women.

PURPOSE

The HEI-2015 is a multidimensional measure of diet quality used to assess how well people's dietary behaviors align with key recommendations of the 2015-2020 Dietary Guidelines for Americans for achieving a healthy dietary pattern. We examined the potential association of the HEI-2015 and bone mineral density (BMD) among adult Iranian women, hypothesizing that a higher HEI-2015 score is associated with greater BMD.

METHODS

Four-hundred sixteen participants (mean age 48.0 years; 64.7% premenopausal) participated in this cross-sectional study. Lumbar spine and femoral neck BMDs were measured via dual-energy X-ray absorptiometry. Dietary intakes were assessed using a valid and reliable food frequency questionnaire. The HEI-2015 score was calculated based on dietary intakes of 13 components emphasized or minimized in the HEI-2015. The higher the HEI-2015 score, the better the diet quality.

RESULTS

After adjusting for potential covariates in the multiple linear regression analysis, higher HEI-2015 scores were associated with greater lumbar spine and femoral neck BMDs (lumbar spine: standardized beta-coefficient [β] = 0.292; femoral neck: β = 0.192; both P < 0.001). Similar significant associations were found among premenopausal (lumbar spine: β = 0.337; femoral neck: β = 0.262; both P < 0.001) and postmenopausal women (lumbar spine: β = 0.198; femoral neck: β = 0.287; both P < 0.050). Overall, every 10-unit increase in the HEI-2015 score was associated with a 0.03 g/cm² higher multivariable-adjusted BMD at both lumbar spine and femoral neck (both P < 0.001).

CONCLUSION

Findings suggest that better diet quality, as indicated by a higher HEI-2015 score, is significantly associated with a small but clinically important increase in BMD among adult Iranian women.

Prudent and traditional dietary patterns are positively and negatively associated with bone mineral density in Iranian adults, respectively

To assess the association of dietary patterns and bone mineral density (BMD), 340 healthy Iranian adults (mean age 41.5 ± 7.7 y; 79.1% female) participated in this cross-sectional study. Lumbar spine and femoral neck BMDs were measured using dual-energy X-ray absorptiometry. Dietary intakes were evaluated by a valid and reliable 168-item food frequency questionnaire, and three major dietary patterns were identified using principal component factor analysis. Mean values for lumbar spine and femoral neck BMDs in participants were 0.96 ± 0.13 and 0.92 ± 0.12 g/cm², respectively. After controlling for age, body mass index, physical activity, energy intake, sunlight exposure, gender, education, employment status, supplement intake, and smoking in the analysis of covariance models, multivariable adjusted means of femoral neck BMD of participants in the highest tertile of the prudent pattern score (rich in green leafy vegetables, other vegetables, tomatoes, yellow vegetables, fruits and fruit juices, olives, nuts, fish, low-fat dairy products, and Doogh) were significantly higher than those in the lowest tertile (mean difference and 95% CI: 0.043 [0.003; 0.083] g/cm², P = 0.032). In contrast, multivariable adjusted means of lumbar spine BMD of participants in the highest tertile of the traditional pattern score (high in Abgoosht, vegetable oils, salt, legumes, pickles, cruciferous vegetables, refined grains, potatoes, and organ meats) were significantly lower than those in the lowest tertile (mean difference and 95% CI: -0.057 [-0.098; -0.015] g/cm², P = 0.003). The Western pattern was not associated with BMD. In conclusion, the prudent and traditional dietary patterns are positively and negatively associated with BMD in Iranian adults, respectively.

Distal radius bone microarchitecture: what are the differences between age 25 and old age?

This study reported that the transitional zones in older adults were enlarged at the expense of the compact-appearing cortex with a greater porosity in all cortical sub-compartments. The magnitude of differences in areal and volumetric bone mineral density (aBMD, vBMD) between older and younger groups was similar.

INTRODUCTION

Aging is strongly associated with bone loss, but little is known about magnitudes of differences in bone microarchitectures, aBMD, and vBMD from peak bone mass (PBM) to senescence. We aimed to describe differences in aBMD, vBMD, and bone microarchitecture parameters at the distal radius between older and young adults.

METHODS

We compared 201 participants, aged 62-89 years (female 47%) and 196 participants, aged 24-28 years (female 38%). Bone microarchitecture parameters at distal radius were measured using high-resolution peripheral computed tomography (HRpQCT). aBMD was measured using dual-energy X-ray absorptiometry (DXA). Unpaired t tests and chi-square tests were used to compare differences in means and proportions as appropriate.

RESULTS

Older adults had thinner compact-appearing cortices with larger (cross-sectional area: outer 30.96 mm² vs. 28.38 mm², inner 36.34 mm² vs. 32.93 mm²) and thicker (outer 0.57 mm vs. 0.54 mm, inner 0.71 mm vs. 0.65 mm) transitional zones compared with young adults (all p < 0.05). Cortical porosity was modestly higher in older adults than in young adults (54% vs. 49%, p < 0.001). The magnitude of the difference in hip aBMD between older and young adults was slightly lower than of total radial vBMD (- 0.51 SD vs. - 0.78 SD).

CONCLUSION

Compared with young adults at the time of PBM, the transitional zones in older adults were enlarged at the expense of the compact-appearing cortex with a greater porosity in all cortical sub-compartments. The similar SD differences in aBMD and vBMD between older and younger groups suggest that the differences in bone area are not leading to major artefactual change in aBMD.

ESR1 polymorphism (rs2234693) influences femoral bone mass in patients with Turner syndrome

Most patients with Turner syndrome (TS) need hormone replacement therapy because of hypergonadotropic hypogonadism; individual outcomes, however, are highly variable. Our objective was to assess the influence of five estrogen receptor 1 gene (ESR1) polymorphisms (rs543650, rs1038304, rs2046210, rs2234693 and rs9340799) on adult height, breast development, uterine volume and bone mineral density (BMD). We studied 91 TS patients from a tertiary hospital using adult estrogen dose. In our group, ESR1 rs2234693 was associated with femoral neck and total hip BMD, and it accounted for around 10% of BMD variability in both sites (P < 0.01). Patients homozygous for C allele in this polymorphism had significantly lower femoral neck BMD (0.699 ± 0.065 g/cm2 vs 0.822 ± 0.113 g/cm2, P = 0.008) and total hip BMD (0.777 ± 0.118 g/cm2 vs 0.903 ± 0.098 g/cm2, P = 0.009) than patients homozygous for T allele. The other four ESR1 polymorphisms were not able to predict any of the above estrogen therapy outcomes in an isolated manner. Patients homozygous for the haplotype GCG formed by polymorphisms rs543650, rs2234693 and rs9340799 had an even more significantly lower femoral neck BMD (0.666 ± 0.049 vs 0.820 ± 0.105 g/cm2, P = 0.0047) and total hip BMD (0.752 ± 0.093 vs 0.908 ± 0.097 g/cm2, P = 0.0029) than patients homozygous for haplotypes with a T allele in rs2234693. In conclusion, homozygosity for C allele in ESR1 rs2234693 and/or for GCG haplotype appears to be associated with lower femoral neck and total hip BMD. We believe that the identification of polymorphisms related to estrogen outcomes may contribute to individualization of treatment in TS.

Dietary Patterns, Bone Mineral Density, and Risk of Fractures: A Systematic Review and Meta-Analysis

The aim of this systematic review was to assess the evidence on the relation between dietary patterns, bone mineral density (BMD), and risk of fracture in different age groups. Medline and Embase were searched for articles that identified dietary patterns and related these to BMD or risk of fracture through May 2018. Multivariable adjusted odds ratios (ORs) and 95% confidence intervals (95%CI) comparing the lowest and highest categories of dietary pattern were combined by using a random effects meta-analysis. In total, 31 studies were selected for review, including 18 cohorts, 1 case-control, and 12 cross-sectional studies, in the meta-analysis of Prudent/healthy and Western/unhealthy dietary pattern, BMD, and risk of fracture. There was evidence of a lower risk of fracture when intakes in the highest categories were compared with the lowest categories of Prudent/healthy dietary pattern (OR = 0.81; 95%CI: 0.69, 0.95; p = 0.01). In contrast, when intakes in the highest categories were compared with the lowest categories of Western/unhealthy dietary pattern, a greater risk of fracture (OR = 1.10; 95%CI: 1.02, 1.19; p = 0.01) was observed among men. The present systematic review and meta-analysis provides evidence of an inverse association between a Prudent/healthy dietary pattern and risk of low BMD and a positive relation between Western/unhealthy dietary pattern and risk of low BMD.

Exploring bone volume and skeletal weight in the Middle Pleistocene humans from the Sima de los Huesos site (Sierra de Atapuerca, Spain)

Body mass estimation in fossil human species is a crucial topic in paleoanthropology as it yields information about ecologically relevant characteristics. Nevertheless, variables crucial to body mass estimation such as bone volume and skeletal weight have never before been calculated in a fossil human species. The exceptional state of preservation of several fossil human long bones from the Sima de los Huesos (SH) Middle Pleistocene site, in the Sierra de Atapuerca, makes it possible to calculate for the first time the absolute bone volume in five complete long bones (two femora and three humeri) of a fossil human species, an approach not possible in fragmentary or poorly preserved fossils. We have relied on computed tomography scans and 3D reconstructions to calculate bone volume. A sample of 62 complete bones of robust recent humans was also used for comparative purposes. The male SH femora (weight-bearing bones) and humeri (non-weight-bearing bones) have, relative to their size, greater bone volume (volume of bone tissue over total bone volume) than the equivalent bones in our recent human sample. As mass is volume × density, and bone tissue density (as a material) is similar across mammals, we calculate bone mass, and our results show that the SH hominins had on average heavier long bones than extant humans of the same size. From the femoral weight at hand, we have estimated the total skeletal weight in two SH individuals, which is about 36% heavier than in the recent humans of the equivalent body size. Using different methods and skeletal variables, including skeletal weight, to estimate body mass in these two SH humans, we highlight the considerable differences in body mass estimates we obtained, and that the largest body mass estimate is the one based on the skeletal weight. Our results suggest that we cannot assume the same relative proportion of bone volume and bone and skeletal weight characterized the entire genus Homo. Given that skeletal weight has a significant influence on body mass, current body mass estimates of fossil Homo specimens could be systematically underestimated. Thus, the significantly larger bone volume and heavier bones, probably throughout the entire skeleton, of SH humans could have had consequences for many biological parameters in this Pleistocene population and considerable importance for studies focusing on adaptive and ecologically relevant characteristics. Although more recent human samples should be analyzed, in our view, the high skeletal robusticity of the SH sample, including larger bone volume and skeletal weight, is part of their adaptive body type selected for throughout the Pleistocene to support different mechanical and activity regimes and formed under tight genetic control, including control over bone formative and regulatory processes.

Tracking of Areal Bone Mineral Density From Age Eight to Young Adulthood and Factors Associated With Deviation From Tracking: A 17-Year Prospective Cohort Study

We have previously shown that bone mineral density (BMD) tracks strongly from age 8 to 16 years. This study aimed to describe whether this strong tracking continued to age 25 years and describe factors associated with deviation from tracking. Ninety-nine participants were followed from age 8 to 25 years and 197 participants from age 16 to 25 years. Outcomes measured were BMD at the spine, hip, and total body (by dual-energy X-ray absorptiometry [DXA]). Other factors measured were anthropometrics, inhaled corticosteroids (ICS) use, history of being breastfed, sports participation, fitness (by physical work capacity [PWC₁₇₀ ]), lean mass (LM), and fat mass (FM) (by DXA). There was moderate to strong tracking of BMD from age 8 to 25 years (correlation coefficients: males, 0.59 to 0.65; females, 0.70 to 0.82) and strong tracking from age 16 to 25 years (males, 0.81 to 0.83; females, 0.84 to 0.88) after adjustment for change in body size. From age 8 to 25 years, 54% to 56% of participants kept their BMD tertile position. PWC₁₇₀ at age 8 years, relative and absolute change in LM, and sports participation at age 25 years predicted males would improve their tertile position or remain in the highest tertile of spine or hip BMD. However, relative and absolute change in FM had the opposite association in males while absolute change in FM predicted positive deviation in females. From age 16 to 25 years, LM, PWC₁₇₀ , sports participation at age 16 years, and change in LM, PWC₁₇₀ , and sports participation at age 25 years predicted positive deviation in males. LM at age 16 years was positively associated and PWC₁₇₀ negatively associated with positive deviation in females. BMD tracks from childhood to early adulthood in both males and females. There appears to be greater capacity to alter tracking before age 16 years. Increasing LM in both sexes and improving fitness and sports participation in males during growth might be effective strategies to improve BMD in early adulthood. © 2017 American Society for Bone and Mineral Research.

Increased levels of sodium chloride directly increase osteoclastic differentiation and resorption in mice and men

To better understand the association between high salt intake and osteoporosis, we investigated the effect of sodium chloride (NaCl) on mice and human osteoclastogenesis. The results suggest a direct, activating role of NaCl supplementation on bone resorption.

INTRODUCTION

High NaCl intake is associated with increased urinary calcium elimination and parathyroid hormone (PTH) secretion which in turn stimulates the release of calcium from the bone, resulting in increased bone resorption. However, while calciuria after NaCl loading could be shown repeatedly, several studies failed to reveal a significant increase in PTH in response to a high-sodium diet. Another possible explanation that we investigated here could be a direct effect of high-sodium concentration on bone resorption.

METHODS

Mouse bone marrow macrophage and human peripheral blood mononuclear cells (PBMC) driven towards an osteoclastogenesis pathway were cultivated under culture conditions mimicking hypernatremia environments.

RESULTS

In this study, a direct effect of increased NaCl concentrations on mouse osteoclast differentiation and function was observed. Surprisingly, in a human osteoclast culture system, significant increases in the number of tartrate-resistant acid phosphatase (TRAP)-positive osteoclasts, calcitonin receptor (CTR)-positive osteoclasts, nuclear factor-activated T cells c1 (NFATc1) gene expression, and areal and volumetric resorptions were observed for increasing concentrations of NaCl. This suggests a direct, activating, cell-mediated effect of increased concentrations of NaCl on osteoclasts.

CONCLUSIONS

The reported that enhanced bone resorption after high-sodium diets may not only be secondary to the urinary calcium loss but may also be a direct, cell-mediated effect on osteoclastic resorption. These findings allow us to suggest an explanation for the clinical findings independent of a PTH-mediated regulation.

Milk-cereal and whole-grain dietary patterns protect against low bone mineral density among male adolescents and young adults

BACKGROUND/OBJECTIVES

Evidence supporting the possible effect of dietary factors on adult bone health has emerged in recent decades. The purpose of this study was to ascertain the influence of different dietary patterns on bone mineral density (BMD) among Korean male youth.

SUBJECTS/METHODS

Data were extracted from the Korean National Health and Nutrition Examination Survey (KNHANES) during 2008-2011. The subjects included 1351 male aged 10-25 years. We defined 'low BMD group' as subjects with a BMD Z-score of -2.0 or less. Dietary patterns were derived from 20 food groups via factor analysis.

RESULTS

Three dietary patterns-meat and vegetable, white rice and kimchi, milk-cereal and whole grain-were derived. The 'milk-cereal and whole-grain' dietary pattern score showed positive association with energy, protein, fat, calcium, phosphorus, potassium, riboflavin and vitamin C intakes. Participants in the top tertile of the milk-cereal and whole-grain pattern were less likely to have low BMD, compared with subjects in the bottom tertile (odds ratio=0.36, 95% confidence interval=0.16-0.81, P=0.018).

CONCLUSIONS

Our findings suggest that the milk-cereal and whole-grain dietary pattern may have a benign influence on bone health in the Korean male youth.

Dietary patterns are associated with bone mineral density in an urban Mexican adult population

Several types of nutrients and foods affect bone mineral density (BMD). However, these nutrients occur together in food groups and dietary patterns, and the overall effects of dietary patterns are not yet well known.

INTRODUCTION

We evaluated the associations between dietary patterns and BMD among adults participating in the Health Workers Cohort Study.

METHODS

In a cross-sectional analysis, we examined 6915 Mexican adults aged 20-80 years. All participants completed a validated self-administered food frequency questionnaire (FFQ) and had total, hip, and spine BMD measurements assessed by dual-energy X-ray absorptiometry (DXA). The FFQ included 116 foods, which were grouped into 22 categories and entered into a factor analysis to derive dietary patterns.

RESULTS

Three dietary patterns emerged-a Prudent, a Refined foods, and a Dairy and fish pattern. After adjustment for potential confounders, those in the highest quintile of the Prudent pattern had lower odds (OR) of low spine BMD (OR = 0.80; 95 % CI 0.68, 0.94; P for trend = 0.031) compared to those in the lowest quintile. In contrast, participants in the highest quintile of the Refined foods pattern had greater odds of low total BMD (OR = 1.74; 95 % CI 1.10, 2.76; P for trend = 0.016) than those in the lowest quintile. Finally, participants in the highest quintile of the Dairy and fish dietary pattern had significantly lower likelihood of having low BMD.

CONCLUSION

This study identified specific dietary patterns associated with BMD among a Mexican adult population and highlights the importance of promoting food-based prevention strategies for maintaining bone health.

Subjective evaluation of the frequency of coffee intake and relationship to osteoporosis in Chinese men

BACKGROUND

The main purpose of this study was to evaluate the associations between frequency of coffee intake and osteoporosis (OP) in a general Chinese male sample.

METHODS

We conducted a large-scale, community-based, cross-sectional study to investigate the associations by using a self-report questionnaire to estimate the frequency of coffee intake. A total of 992 men were available for data analysis in this study. Multiple regression models controlling for confounding factors to include frequency of coffee intake variable were performed to investigate the relationships for OP.

RESULTS

Positive correlations between frequency of coffee intake and T-score were reported (β = 0.211, P = 0.024). Multiple regression analysis indicated that the frequency of coffee intake was significantly associated with OP (P < 0.05 for model 1 and model 2). The men with moderate frequency of coffee intake had a lower prevalence of OP.

CONCLUSIONS

The findings indicated that consumption of coffee was independently and significantly associated with OP. The prevalence of OP was less frequent in Chinese men with moderate coffee intake.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT02451397.

A Cross-Sectional Study of the Association of VDR Gene, Calcium Intake, and Heel Ultrasound Measures in Early Adulthood

The acquisition of a high adult peak bone mass (PBM) is considered an important determinant of osteoporotic risk later in life. Genetic and environmental factors determine optimal PBM acquisition in early adulthood. The aim of this study was to test the association of vitamin D receptor (VDR) gene polymorphisms and dietary calcium intake with the bone mass of young adults. The study population comprised a total of 305 individuals (mean age 20.41; SD 2.36) whose bone mass was assessed through heel ultrasound [quantitative ultrasound measurements (QUS)] measurements (BUA, dB/MHz). The FokI G/A, rs9729 G/T, and TaqI G/A polymorphisms were selected as genetic markers of VDR. A significant difference in BUA values was observed according to gender (females 82.96; SD 15.89 vs. males 97.72; SD 16.50; p < 0.00001). The mean dietary calcium intake of the study group (827.84 mg/day; SD 347.04) was lower than the dietary reference intake for young adults (1000 mg/day) and had no association with BUA. None of the three VDR polymorphisms tested showed an association with BUA. Similarly, the analysis of VDR 3' haplotypes, estimated using rs9729 and Taq1 as tag SNPs, did not reveal any significant association with QUS traits. Our results confirm the existence of different heel QUS for women and men, as well as a tendency towards low calcium consumption by young adults, and they also suggest that the VDR gene does not play a major role in the genetic determination of QUS parameter in early adulthood.

Four biomechanical and anthropometric measures predict tibial stress fracture: a prospective study of 1065 Royal Marines

Background

Tibial stress fractures (TSFs) cause a significant burden to Royal Marines recruits. No prospective running gait analyses have previously been performed in military settings.

Aim

We aimed to identify biomechanical gait factors and anthropometric variables associated with increased risk of TSF.

Methods

1065 Royal Marines recruits were assessed in week 2 of training. Bilateral plantar pressure and three-dimensional lower limb kinematics were obtained for barefoot running at 3.6 m/s, providing dynamic arch index, peak heel pressure and lower limb joint angles. Age, bimalleolar breadth, calf girth, passive hip internal/external range of motion and body mass index (BMI) were also recorded. 10 recruits who sustained a TSF during training were compared with 120 recruits who completed training injury-free using a binary logistic regression model to identify injury risk factors.

Results

4 variables significantly (p<0.05) predicted increased risk of TSF (ORs and 95% CI): smaller bimalleolar width (0.73, 0.58 to 0.93), lower BMI (0.56, 0.33 to 0.95), greater peak heel pressure (1.25, 1.07 to 1.46) and lower range of tibial rotation (0.78, 0.63 to 0.96).

Summary

Reduced impact attenuation and ability to withstand load were implicated in tibial stress fracture risk.

Epigenetics of Osteoporosis: Critical Analysis of Epigenetic Epidemiology Studies

Osteoarthritis (OA) is an age-related disease with poorly understood pathogenesis. Recent studies have demonstrated that miRNA might play a key role in OA initiation and development. We reviewed recent publications and elucidated the connection between miRNA and OA cartilage anabolic and catabolic signals, including four signaling pathways: TGF-β/Smads and BMPs signaling, associated with cartilage anabolism; and MAPK and NF-KB signaling, associated with cartilage catabolism. We also explored the relationships with MMP, ADAMTS and NOS (NitricOxide Synthases) families, as well as with the catabolic cytokines IL-1 and TNF-α. The potential role of miRNAs in biological processes such as cartilage degeneration, chondrocyte proliferation, and differentiation is discussed. Collective evidence indicates that miRNAs play a critical role in cartilage degeneration. These findings will aid in understanding the molecular network that governs articular cartilage homeostasis and in to elucidate the role of miRNA in the pathogenesis of OA.

Ontogeny of the male femur: Geometric morphometric analysis applied to a contemporary Spanish population

OBJECTIVE

To describe the morphological changes of the male femur during the adolescent growth spurt and to compare the pattern obtained with that reported previously for females.

MATERIAL AND METHODS

Two hundred and forty males from a Spanish population aged between 9 and 16 years were analysed, based on telemetries. Size and shape variation of the femur was quantified by 22 2D-landmarks and analysed using geometric morphometric methods. Likewise, the variation of neck-shaft and bicondylar angles were also determined and evaluated by Student's t-test. Sexual differences were analysed by comparing results here obtained on boys with those corresponding to girls reported in a previous study.

RESULTS

In males, both size and shape varied significantly with age, with males having larger dimensions than females. In general terms, these changes are generally characterised by an increase in robustness of the femur and shape modifications in the epiphyses. During growth, the neck-shaft angle decreases and the size of the greater and lesser trochanters increase. A significant increase of distal epiphyseal dimensions was recorded, mainly in the medial condyle. The angular remodeling of both the neck and the bicondylar regions of the male femur continues until 16 and 15 years, respectively. Female and male femur each followed divergent growth trajectories. Males showed a greater variability in neck-shaft and bicondylar angles than females.

DISCUSSION

The timing, morphology and growth trajectories provided on the femur during development can be very helpful in anthropological, paleoanthropological and evolution studies.

Prematurity and low birth weight lead to altered bone geometry, strength, and quality in children

PURPOSE

Prematurity and low birth weight are associated with a decrease in bone mass. Aim of the study was to investigate bone geometry, strength, and quality in children born at term small for gestational age (term SGA), premature appropriate for gestational age (prem AGA), and premature SGA (prem SGA).

METHODS

91 patients (46 f, 45 m), mean age 11.28 years, height SDS 0.03 ± 0.21, and BMI SDS -0.31 ± 0.19. 20 were term SGA, 22 prem SGA, and 49 prem AGA. Bone geometry was assessed on the 2nd metacarpal bone, by evaluating the outer and inner diameter, the cortical area, medullary area, metacarpal index, cross-sectional area, and bone strength. Bone quality was evaluated by ultrasound and expressed as amplitude-dependent speed of sound and bone transmission time (BTT).

RESULTS

Term SGA, prem SGA, and prem AGA had values of bone geometry, strength, and quality significantly lower than our reference range (p < 0.05). Findings in the three groups were similar, apart from BTT, which was significantly reduced in prem SGA (p < 0.05). Fat percentage was the main determinant of BTT.

CONCLUSIONS

Children born either prematurely or SGA seem to have smaller and weaker bones. Those born both premature and SGA were the most affected.

Increased inflammatory potential of diet is associated with bone mineral density among postmenopausal women in Iran

PURPOSE

Diet has been shown to be associated with bone mineral density (BMD); however, the inflammatory potential of diet in modulating BMD has not yet been studied.

METHODS

We examined the association between a newly developed dietary inflammatory index (DII) and BMD in a sample of postmenopausal Iranian women. In this cross-sectional study, 160 postmenopausal women aged 50-85 years were studied and their femoral neck and lumbar spine BMDs were measured by dual-energy X-ray absorptiometry. The DII was computed based on dietary intake assessed using a previously validated, 168-item semiquantitative food frequency questionnaire. Logistic and linear regression models were fit to derive beta estimates and odds ratios (ORs), with DII fit as continuous and as a dichotomous variable.

RESULTS

After adjusting for potential confounders, women with higher DII scores were more likely to have BMD below the median in the lumbar spine with the DII being used as both a continuous variable [ORcontinuous 1.64, 95 % confidence interval (CI) 1.11-2.43, p value = 0.01; one-unit increase corresponding to ≈17 % of its range in the current study] and a categorical variable (ORDII>-0.06/≤ 2.30, 95 % CI 1.05-5.07, p value = 0.04). Similar associations were observed when lumbar spine BMD was used as a continuous outcome. No significant association was observed with BMD in femoral neck, although the direction was along expected lines.

CONCLUSION

These data suggest a pro-inflammatory diet, as indicated by increasing DII score, may be a risk factor for lower BMD in lumbar spine in postmenopausal Iranian women.

A Prospective Cluster-Randomized Trial of Telehealth Coaching to Promote Bone Health and Nutrition in Deployed Soldiers

Findings from previous studies suggest that inadequate consumption of calcium and vitamin D and a decrease in exercise while deployed can be detrimental to bone health. This study enrolled 234 soldiers randomized to receive one-time nutrition and exercise education pre-deployment (n = 149), or telehealth coaching (n = 85), throughout the deployment cycle. Results suggest that online educational efforts may enhance sports activity, bone turnover, and vitamin D status. Improving vitamin D status and remaining active while deployed appears to sustain healthy bone density in young soldiers. Early and aggressive educational outreach to young adults may prevent chronic musculoskeletal conditions and disabling osteoporosis later in life.

Bone status of children born from mothers with autoimmune diseases treated during pregnancy with prednisone and/or low molecular weight heparin

BACKGROUND

To evaluate bone status in children born from mothers followed for autoimmune diseases and treated during pregnancy with low molecular weight heparin (LMVH) and/or prednisone.

FINDINGS

History, physical examination, laboratory tests and phalangeal ultrasonography were performed. Demographic, clinical, and laboratory data were entered into a customized database, and results were analyzed with SPSS software. In children whose mothers were treated with LMWH, we retrieved dried blood spots taken for newborn screening, and analyzed the presence of heparin with tandem mass spectrometry. We enrolled 27 females and 14 males born from 31 mothers with SLE or connective tissue diseases. These women were continuously treated during pregnancy with LMWH (n = 10), prednisone (n = 16), or both (n = 15). Bone ultrasound revealed low values (≤ 3 centile for age) in ten patients. In a multistep regression analysis, age at examination resulted the single predictor of low ultrasound values (p < 0.004). Tandem mass spectroscopy failed to determine traces of heparin in newborn blood.

CONCLUSIONS

Children born from mothers with autoimmune diseases are at risk to develop reduced bone mass. The administration of LMWH and of prednisone seems to be safe with regard to children's bone health.

Impact of orange juice consumption on bone health of the U.S. population in the national health and nutrition examination survey 2003-2006

Orange juice (OJ) fortified with calcium (Ca) and vitamin D has turned OJ into a readily available source of these nutrients for children and adults. However, the impact of OJ consumption on Ca and vitamin D adequacy and bone health has not been documented. The aim of this study was the evaluation of the contribution of 100% OJ consumption to dietary and serum Ca and vitamin D status, and bone health parameters in the U.S. population aged 4 years and older (n=13,971) using the National Health and Nutrition Examination Survey (NHANES) 2003-2004 and 2005-2006. Food consumption data were coded to produce micronutrient intake values using the USDA Food and Nutrient Database for Dietary Studies 3.0. Serum concentrations of bone-related micronutrients and biomarkers, bone mineral density (BMD), and bone mineral content (BMC) were measured. Analysis of data was conducted using SAS software 9.2 and SUDAAN. OJ consumers showed higher intakes of bone-related micronutrients, compared with nonconsumers (P<.05). In addition, OJ consumers had higher serum Ca levels in adults (P<.01) and had a lower odds ratio for serum 25-hydroxyvitamin D3 <20 ng/mL in children (P<.05). OJ consumption was positively associated with femur BMD in children (P<.05) and with femur BMC in both children and adults (P<.05). In conclusion, OJ may be recommended as an effective dietary means of improving the status of Ca and vitamin D, acid-base balance, and of promoting bone health in children and adults.

Ontogeny of the female femur: geometric morphometric analysis applied on current living individuals of a Spanish population

In this study we describe the development of the female femur based on the analysis of high-resolution radiographic images by means of geometric morphometrics, while assessing the usefulness of this method in these kinds of studies. The material analysed consisted of digital images in DICOM format (telemetries), corresponding to 184 left femora in anterior view, obtained from the database of the Hospital Sant Joan de Déu of Barcelona (Spain). Bones analysed corresponded to individuals from 9 to 14 years old. Size and shape variation of the entire femur was quantified by 22 two-dimensional landmarks. Landmark digitisation errors were assessed using Procrustes anova test. Centroid size (CS) variation with age was evaluated by an anova test. Shape variation was assessed by principal component analysis. A mancova test between the first five principal components and age, using the CS as covariable, was applied. Results indicated that both size and shape vary significantly with age. Several age-related shape changes remained significant after removing the allometric effect. In general, an increase in the robustness of the bone and noticeable phenotypic changes in certain areas of the femur were observed. During growth in the proximal region of the femur, the collo-diaphyseal angle decreases, the neck of the femur widens and the fovea moves to a lower position, standing more in line with the plane of the neck. Likewise, the size of the greater and lesser trochanters increase. In the distal region, a significant increase of epiphyseal dimensions was recorded, mainly in the medial condyle. The angular remodelling of the neck and the bicondylar region of the femur in females continues until 13 years old. The information provided in the present study increases our knowledge on the timing and morphology of the femur during development, and in particular the morphology of the different femoral ossification centres during development.

Major nutrient patterns and bone mineral density among postmenopausal Iranian women

Our understanding of the influence of overall nutrient intake on bone mineral density (BMD) is limited because most studies to date have focused on the intakes of calcium, vitamin D, or a few isolated nutrients. Therefore, we examined the association of major nutrient patterns with BMD in a sample of postmenopausal Iranian women. In this cross-sectional study, 160 women aged 50-85 years were studied and their lumbar spine and femoral neck BMDs were measured using dual-energy X-ray absorptiometry. Dietary intakes were assessed using a validated 168-item food frequency questionnaire, and daily intakes of 30 nutrients were calculated. All nutrient intakes were energy adjusted by the residual method and were submitted to principal component factor analysis to identify major nutrient patterns. Overall, three major nutrient patterns were identified, among which only the first pattern, which was high in folate, total fiber, vitamin B6, potassium, vitamin A (as retinol activity equivalent), vitamin C, β-carotene, vitamin K, magnesium, copper, and manganese, had a significant association with BMD. After controlling for potential confounders, multivariate adjusted mean of the lumbar spine BMD of women in the highest tertile of the first pattern scores was significantly higher than those in the lowest tertile (mean difference 0.08; 95% confidence interval 0.02-0.15; P = 0.01). A nutrient pattern similar to pattern 1, which is associated with high intakes of fruits and vegetables, may be beneficial for bone health in postmenopausal Iranian women.

Associations between a posteriori defined dietary patterns and bone mineral density in adolescents

PURPOSE

Dietary pattern analysis may uncover the joint effects of multiple dietary components on bone health, but such research is scarce and targets mostly adults.

METHODS

We quantified prospective associations between dietary patterns and bone mineral density (BMD) in 1,007 adolescents of a cohort born in 1990 and recruited at schools in Porto during the 2003/2004 school year. Forearm BMD was measured using dual-energy X-ray absorptiometry. Participants' dietary patterns were classified "Healthier", "Dairy products", "Fast food and sweets" and "Lower intake" according to previously identified patterns obtained in a larger sample of 1,489 participants using the K-means method. Using dietary patterns at 13 years old as the main exposure, associations were estimated cross-sectionally (with BMD at the age of 13) and prospectively (with annual BMD variation between 13 and 17 years), using linear regression coefficients adjusted for height, weight, energy intake and, in girls, for menarche age.

RESULTS

No significant associations between the a posteriori dietary patterns identified and mean BMD at 13 were found. However, among girls, adherence to a pattern characterized by low intake of energy and all food groups was negatively associated with annual BMD variation between 13 and 17 years [adjusted coefficient (95 % CI) -0.451 (-0.827; -0.074) mg·cm⁻²·year⁻¹].

CONCLUSIONS

Although results showed that, in girls, adherence to a "Lower intake" dietary pattern is associated with lower annual BMD variation throughout adolescence, overall, there were no consistent associations between dietary patterns and forearm BMD in adolescents.

Polyalanine repeat polymorphism in RUNX2 is associated with site-specific fracture in post-menopausal females

Runt related transcription factor 2 (RUNX2) is a key regulator of osteoblast differentiation. Several variations within the RUNX2 gene have been found to be associated with significant changes in BMD, which is a major risk factor for fracture. In this study we report that an 18 bp deletion within the polyalanine tract (17A>11A) of RUNX2 is significantly associated with fracture. Carriers of the 11A allele were found to be nearly twice as likely to have sustained fracture. Within the fracture category, there was a significant tendency of 11A carriers to present with fractures of distal radius and bones of intramembranous origin compared to bones of endochondral origin (p = 0.0001). In a population of random subjects, the 11A allele was associated with decreased levels of serum collagen cross links (CTx, p = 0.01), suggesting decreased bone turnover. The transactivation function of the 11A allele showed a minor quantitative decrease. Interestingly, we found no effect of the 11A allele on BMD at multiple skeletal sites. These findings suggest that the 11A allele is a biologically relevant polymorphism that influences serum CTx and confers enhanced fracture risk in a site-selective manner related to intramembranous bone ossification.

Birth weight is more important for peak bone mineral content than for bone density: the PEAK-25 study of 1,061 young adult women

Lower birth weight has a negative association with adult BMC and body composition in young adult Swedish women.

INTRODUCTION

The aim of this study was to evaluate the influence of birth weight on peak bone mass and body composition in a cohort of 25-year-old women.

METHODS

One thousand sixty-one women participated in this cross-sectional population-based study using dual energy X-ray absorptiometry (DXA) to assess bone mineral content (BMC), bone mineral density (BMD), and body composition (total body (TB), femoral neck (FN), total hip (TH), lumbar spine L1-L4 (LS), and lean and fat mass). Birth weight data was available for 1,047 women and was categorized into tertiles of low (≤3,180 g), intermediate (3,181-3,620 g), and high (≥3,621 g) birth weight.

RESULTS

Significant correlations were observed between birth weight and TB-BMC (r=0.159, p<0.001), FN-BMC (r=0.096, p<0.001), TH-BMC (r=0.102, p=0.001), LS-BMC (r=0.095, p=0.002), and lean mass (r=0.215, p<0.001). No correlation was observed between birth weight and BMD. The estimated magnitude of effect was equivalent to a 0.3-0.5 SD difference in BMC for every 1 kg difference in birth weight (151 g (TB); 0.22 g (FN); 1.5 g (TH), 2.5 kg TB lean mass). The strongest correlations between birth weight and BMC occurred in women with lowest birth weights, although excluding women who weighed<2,500 g at birth, and the correlation remained significant although slightly weaker.

CONCLUSIONS

Women with lower birth weight have lower BMC and less lean and fat mass at the age of 25, independent of current body weight. Lower birth weight has a greater negative influence on bone mass than the positive influence of higher birth weight.

Physical activity during life course and bone mass: a systematic review of methods and findings from cohort studies with young adults

Background

The purpose of this paper was to review the literature of the cohort studies which evaluated the association between physical activity during the life course and bone mineral content or density in young adults.

Methods

Prospective cohort studies with bone mineral density or content measured in the whole body, lumbar spine and femoral neck by dual energy x-ray absorptiometry as outcome and physical activity as exposure were searched. Two independent reviewers selected studies retrieved from electronic databases (Medline, Lilacs, Web of Science and Scielo) and reviewed references of all selected full text articles. Downs & Black criterion was used in the quality assessment of these studies.

Results

Nineteen manuscripts met inclusion criteria. Lumbar spine was the skeletal site most studied (n = 15). Different questionnaires were used for physical activity evaluation. Peak strain score was also used to evaluate physical activity in 5 manuscripts. Lack of statistical power calculation was the main problem found in the quality assessment. Positive associations between physical activity and bone mass were found more in males than in females; in weight bearing anatomical sites (lumbar spine and femoral neck) than in total body and when physical activity measurements were done from adolescence to adulthood – than when evaluated in only one period. Physical activity during growth period was associated with greater bone mass in males. It was not possible to conduct pooled analyses due to the heterogeneity of the studies, considering mainly the different instruments used for physical activity measurements.

Conclusions

Physical activity seems to be important for bone mass in all periods of life, but especially the growth period should be taking into account due to its important direct effect on bone mass and its influence in physical activity practice in later life. Low participation in peak strain activities may also explain the lower number of associations found in females.

Life-course evidence of birth weight effects on bone mass: systematic review and meta-analysis

A systematic review of the literature was performed in July 2011. Original papers based on longitudinal studies measuring spine, femoral neck, or total body bone mass by DXA were included (n = 17). Birth weight was positively associated with bone mass among children. The association was unclear among adolescents and weak among adults. This study aims to evaluate the association between birth weight and bone mass in future ages through a systematic review of literature and meta-analysis. A systematic review of the literature was performed in July 2011 in Medline, Web of Science and LILACS bases using key terms: ("birth size" OR "birth weight" OR birthweight OR prematurity OR premature OR "gestational age") AND (osteoporosis OR "bone mass" OR "bone density" OR "bone mineral density" OR "bone mineral content" OR "bone area") AND (longitudinal OR cohort). Original papers based on longitudinal studies measuring lumbar spine, femoral neck or total body bone mass by dual-emission X-ray absorptiometry (DXA) were included. A meta-analysis was performed using birth weight and bone mass density and/or content as continuous variables and adjusted for current height and/or weight. A total of 218 articles were retrieved from which 17 were selected and grouped into three categories according to age: studies with children; with adolescents and young adults, and studies with adults (older than 25). Five papers were included in the meta-analysis. Positive association between birth weight and bone mass was clear among children, unclear among adolescents, and weak among adults. The effect on bone mass content was stronger than those on body mass density regardless of age. Birth weight influences positively bone health in later life. Preventive health policies dealing with early-life modifiable risk factors, as birth weight, should be encouraged to attain an optimal peak bone mass as an strategy to decrease osteoporosis in the elderly.

Influence of heredity and environment on peak bone density: a review of studies in Croatia

One of the main determinants of who will develop osteoporosis is the amount of bone accumulated at peak bone density. There is poor agreement, however, on when peak bone density occurs. Ethnic differences were observed in age at peak bone density and their correlates. Since the diagnosis of osteoporosis and osteopaenia is based on the comparison between patients' bone mineral density (BMD) and optimal peak bone density in healthy young people (T-score), it is of great importance that each country should provide its own reference peak bone density data.This review article presents our published results on peak bone density in Croatia and compares them with findings in other populations. Our research included 18 to 25-year-old students from Zagreb University and their parents. The results showed that peak bone mass in young Croatian women was achieved before the age of twenty, but BMD continued to increase after the mid-twenties in the long-bone cortical skeleton. BMD was comparable to the values reported by the National Health and Nutrition Examination Survey (NHANES) and other studies that included the same age groups, except for the cortical part of the radius, where it was significantly lower. Men achieved peak bone density in the spine later than women, which cannot be explained by different diet or physical activity. As expected, heredity was more important for peak bone density than the environmental factors known to be important for bone health. However, the influence of heredity was not as strong as observed in most other populations. It was also weaker in the cortical than in the trabecular parts of the skeleton. Future research should include young adolescent population to define the exact age of achieving peak bone density in different skeletal sites.

Glutamine repeat variants in human RUNX2 associated with decreased femoral neck BMD, broadband ultrasound attenuation and target gene transactivation

RUNX2 is an essential transcription factor required for skeletal development and cartilage formation. Haploinsufficiency of RUNX2 leads to cleidocranial displaysia (CCD) a skeletal disorder characterised by gross dysgenesis of bones particularly those derived from intramembranous bone formation. A notable feature of the RUNX2 protein is the polyglutamine and polyalanine (23Q/17A) domain coded by a repeat sequence. Since none of the known mutations causing CCD characterised to date map in the glutamine repeat region, we hypothesised that Q-repeat mutations may be related to a more subtle bone phenotype. We screened subjects derived from four normal populations for Q-repeat variants. A total of 22 subjects were identified who were heterozygous for a wild type allele and a Q-repeat variant allele: (15Q, 16Q, 18Q and 30Q). Although not every subject had data for all measures, Q-repeat variants had a significant deficit in BMD with an average decrease of 0.7SD measured over 12 BMD-related parameters (p = 0.005). Femoral neck BMD was measured in all subjects (-0.6SD, p = 0.0007). The transactivation function of RUNX2 was determined for 16Q and 30Q alleles using a reporter gene assay. 16Q and 30Q alleles displayed significantly lower transactivation function compared to wild type (23Q). Our analysis has identified novel Q-repeat mutations that occur at a collective frequency of about 0.4%. These mutations significantly alter BMD and display impaired transactivation function, introducing a new class of functionally relevant RUNX2 mutants.

Predictors of bone mineral density in a convenience sample of young Caucasian adults living in southern Ontario

Osteoporosis is a major public health concern in Canada and worldwide. Although much is known about bone health in older adults, little is known about bone health in young, healthy Canadian men and women. The objectives of this research were to describe bone mineral density (BMD) of young, healthy adults living in southern Ontario, Canada, and to identify predictors of BMD in this population. Two-hundred and fifty-eight Caucasian men and women aged 18–33 years completed health and physical activity questionnaires along with a calcium and vitamin D specific food frequency questionnaire. Height and mass were measured. BMD of the total hip, femoral neck, spine, and total body was measured using dual energy X-ray absorptiometry. Among men, body mass, weight-bearing physical activity, and calcium intake were significant predictors of BMD. Among women, body mass, calcium intake, and family history of osteoporosis significantly predicted log BMD. The predictors of BMD in young Canadian men and women identified in this study may inform the development of longitudinal studies designed to examine the influence of lifestyle factors on BMD in young adults.

Dietary patterns in relation to bone mineral density among menopausal Iranian women

The association of dietary patterns and bone health is not yet well known, and findings from the rare previous studies conducted on this issue are contradictory. We assessed the dietary patterns in relation to bone mineral density (BMD) in a sample of menopausal Iranian women. In this cross-sectional study, 160 menopausal women aged 50-85 were studied and their femoral neck and lumbar spine BMDs were measured by dual-energy X-ray absorptiometry. Dietary intakes were assessed with a validated 168-item food frequency questionnaire, and dietary patterns were identified by a principal component factor analysis method. Overall, six dietary patterns emerged, two of which had a significant association with BMD. After adjusting for potential confounders, women who had higher scores for the first (high in high-fat dairy products, organ meats, red or processed meats and nonrefined cereals) and the second (high in French fries, mayonnaise, sweets and desserts and vegetable oils) dietary patterns we identified were more likely to have BMD below the median in the lumbar spine (odds ratio 2.29; 95 % confidence interval 1.05-4.96; p = 0.04) and the femoral neck (odds ratio 2.83, 95 % confidence interval 1.31-6.09; p < 0.01), respectively, compared to women with lower scores. Dietary patterns abundant in foods with high content of saturated fatty acids (similar to factor 1) or with low density of nutrients (similar to factor 2) are detrimental to bone health in menopausal Iranian women. These findings highlight the importance of proper food selection for maintaining bone health.

Estrogen receptors α and β have different gender-dependent effects on the adaptive responses to load bearing in cancellous and cortical bone

To determine the effect of estrogen receptors (ER) α and β on bones' adaptive response to loading, we subjected the right tibiae of mice lacking ERα or ERβ activity to either axial loading or to disuse. Adaptive changes in architecture were assessed by comparing differences between the right (treated) and left (control) tibiae in these genotypes as assessed by microcomputed tomography. In female ERα(-/-) mice, the net-osteogenic response to loading was lower in cortical bone compared with their wild-type littermates (11.2 vs. 20.9% in ERα(+/+)), but it was higher in both cortical and cancellous bone of male ERα(-/-) mice (cortical 20.0 vs. 4.6% in ERα(+/+); cancellous 30.0 vs. 5.3% in ERα(+/+), P < 0.05). In ERβ(-/-) male and female mice, the net-osteogenic response to loading was higher in cortical bone (males 10.9 vs. 3.9% in ERβ(+/+); females 18.5 vs. 15.8% in ERβ(+/+), P < 0.05) but no different from controls in cancellous bone. The bone loss in response to disuse was less in cancellous bone of ERα(-/-) mice than in controls (-15.9 vs. -21.3%, respectively, P < 0.05) but no different at any other site or between any other groups. Our conclusion is that functional ERα enhances the net-osteogenic response to loading in cortical but not cancellous bone in female mice but reduces it in males. ERβ decreases the response to loading in cortical bone of males and females but has no effect in cancellous bone. Bone loss due to disuse in cortical bone is unaffected by ER status, but in cancellous bone, functional ERα contributes to greater disuse-related bone loss.

Endosteal bone storage in young adults born small for gestational age - a study using peripheral quantitative computed tomography

OBJECTIVE

Poor growth early in life is associated with numerous adverse conditions including decreased bone mass. The aim is to investigate bone and body composition in young adults born small for gestational age (SGA).

DESIGN

Observational study.

PARTICIPANTS

A total of 76 young adults born SGA (34f) at a mean age of 19·68 ± 0·5 years were enrolled.

METHOD

Bone mineral density (BMD), bone geometry and body composition were analysed using peripheral quantitative computed tomography.

RESULTS

Adults born SGA had significantly lower z-score for height (-0.86 ± 0·87), weight (-0·61 ± 0·78) and BMI (-0·38 ± 1·04) as well as fat cross-sectional area (CSA) (-0·62 ± 0·80) compared with a healthy reference population (P < 0·05). Z-scores for trabecular and cortical BMD were normal. After correction for reduced height, z-scores for total CSA (-0·14 ± 1·11) and muscle CSA (-0·21 ± 0·99) were normal and medullary cavity (-0·71 ± 0·80) was reduced. Those with a birthweight of ≤ 1500 g had even lower height-corrected z-scores for medullary cavity (-1·12 ± 0·69) and total bone CSA (-0·58 ± 0·93) (P < 0·05). After adjustment for sex and weight, significant partial correlations were detectable between BMI at the age of 48 months and height-corrected z-scores for medullary cavity (r = 0·33, P = 0·020) and total CSA (r = 0·29, P = 0·04).

CONCLUSION

Environmental factors early in life seem to influence bone geometry in adulthood. Young adults born SGA have normal total bone CSA but smaller medullary cavity. Those with very low birthweight, however, show compromised bone size development that may alter bone stability later in life.

Peak bone mineral density and its determinants in an Asian Indian population

Data on peak bone mineral density (BMD) and its determinants in Asian Indians are limited. We studied the peak BMD and its determinants in Asian Indians. A total of 1137 young (age: 25--35yr) healthy volunteers of either sex (558 men and 579 women) were recruited for dietary evaluation, analyses of serum calcium, inorganic phosphorus, alkaline phosphatase, 25-hydroxyvitamin D [25(OH)D], and intact parathyroid hormone (iPTH) levels, and measurement of BMD with dual-energy X-ray absorptiometry. In men and women, peak bone mass (PBM) at the femoral neck, femoral trochanter, total femur, and lumbar spine was achieved between 25 and 30yr of age, whereas PBM at the femoral intertrochanter occurred between 30 and 35yr of age. Peak BMD was lower than that of Caucasians by 15.2--21.1% in men and 14.4--20.6% in women. On stepwise multiple regression, height and weight were the most consistent predictors of BMD at all sites in both groups. In men, 25(OH)D positively predicted BMD at the hip, whereas in women, serum iPTH negatively predicted BMD at the femoral trochanter and total femur. The study concluded that Asian Indians have significantly lower peak BMD than Caucasians and that weight and height are the most consistent predictors of BMD at all sites in both men and women.

Integrated imaging approach to osteoporosis: state-of-the-art review and update

Osteoporosis is the most common of all metabolic bone disorders. It is characterized by low bone mass and microarchitectural deterioration of bone tissue, with a consequent increase in bone fragility and susceptibility to fractures. Because of the increasing aging of the world population, the number of persons affected by osteoporosis is also increasing. Complications related to osteoporosis can create social and economic burdens. For these reasons, the early diagnosis of osteoporosis is crucial. Conventional radiography allows qualitative and semiquantitative evaluation of osteoporosis, whereas other imaging techniques allow quantification of bone loss (eg, dual-energy x-ray absorptiometry and quantitative computed tomography [CT]), assessment for the presence of fractures (morphometry), and the study of bone properties (ultrasonography). In recent years, new imaging modalities such as micro-CT and high-resolution magnetic resonance imaging have been developed in an attempt to help diagnose osteoporosis in its early stages, thereby reducing social and economic costs and preventing patient suffering. The correct diagnosis of osteoporosis results in better management in terms of prevention and adequate pharmacologic or surgical treatment.

Concerted actions of insulin-like growth factor 1, testosterone, and estradiol on peripubertal bone growth: a 7-year longitudinal study

A better understanding of how bone growth is regulated during peripuberty is important for optimizing the attainment of peak bone mass and for the prevention of osteoporosis in later life. In this report we used hierarchical models to evaluate the associations of insulin-like growth factor 1 (IGF-1), estradiol (E(2) ), and testosterone (T) with peripubertal bone growth in a 7-year longitudinal study. Two-hundred and fifty-eight healthy girls were assessed at baseline (mean age 11.2 years) and at 1, 2, 3.5, and 7 years. Serum concentrations of IGF-1, E(2) , and T were determined. Musculoskeletal properties in the left lower leg were measured using peripheral quantitative computed tomography (pQCT). Serum levels of IGF-1, E(2) , and T increased dramatically before menarche, whereas they decreased, plateaued, or increased at a lower rate, respectively, after menarche. IGF-1 level was positively associated with periosteal circumference (PC) and total bone mineral content (tBMC) throughout peripuberty but not after adjustment for muscle cross-sectional area (mCSA). On the other hand, IGF-1 was associated with tibial length (TL) independently of mCSA before menarche. T was positively associated with TL, PC, tBMC, and cortical volumetric bone mineral density, independent of mCSA, before menarche but not after. E(2) was associated with TL positively before menarche but negatively after menarche. These findings suggest that during puberty, circulating IGF-1 promotes bone periosteal apposition and mass accrual indirectly, probably through stimulating muscle growth, whereas the effects of sex steroids on bone growth differ before and after menarche, presenting a biphasic pattern. Hence the concerted actions of these hormones are essential for optimal bone development in peripuberty.

Does birthweight predict bone mass in adulthood? A systematic review and meta-analysis

SUMMARY

This systematic review and meta-analysis assessed the strength and magnitude of the association between birthweight and adult bone mass. Higher birthweight was associated with higher bone mineral content of the spine and hip in adult men and women at ages between 18 and 80 years across a range of settings.

INTRODUCTION

The aim of this review was to assess the strength and magnitude of the association between early size and adult bone mass.

METHODS

Systematic review and meta-analysis of studies that assessed the association between birthweight or weight at 1 year, and bone mineral content (BMC) or bone mineral density (BMD) in adulthood.

RESULTS

Fourteen studies met inclusion criteria. Nine assessed the relationship between birthweight and lumbar spine BMC, most showing that higher birthweight was associated with greater adult BMC. Meta-analysis demonstrated that a 1 kg increase in birthweight was associated with a 1.49 g increase in lumbar spine BMC (95% CI 0.77-2.21). Birthweight was not associated with lumbar spine BMD in 11 studies. In six studies, considering the relationship between birthweight and hip BMC, most found that higher birthweight was associated with greater BMC. Meta-analysis demonstrated that a 1 kg increase in birthweight was associated with a 1.41 g increase in hip BMC (95% CI 0.91-1.91). Seven studies considered the relationship between birthweight and hip BMD and, in most, birthweight was not a significant predictor of hip BMD. Three studies assessing the relationship between weight at 1 year and adult bone mass all reported that higher weight at one was associated with greater BMC of the lumbar spine and hip.

CONCLUSIONS

Higher birthweight is associated with greater BMC of the lumbar spine and hip in adulthood. The consistency of these associations, across a range of settings, provides compelling evidence for the intrauterine programming of skeletal development and tracking of skeletal size from infancy to adulthood.