Racial/ethnic differences in bone mineral density among older women

Effects of Synbiotic Supplementation on Bone and Metabolic Health in Caucasian Postmenopausal Women: Rationale and Design of the OsteoPreP Trial

BACKGROUND/OBJECTIVES

Correction of decreased diversity of the gut microbiome, which is characteristic of menopause, by supplementation with a synbiotic may attenuate or prevent dysbiosis processes and preserve bone mass. We describe the rationale and design of the OsteoPreP trial aimed at evaluating the effects of 12 months of supplementation with a synbiotic on bone and metabolic health in postmenopausal Caucasian women.

METHODS

This is a randomized, double-blinded, placebo-controlled trial among 160 Caucasian, postmenopausal women with no current diagnosis of osteoporosis or supplementation with pro- or prebiotics, and no medical treatment affecting bone turnover. Dual-energy X-ray absorptiometry scans will be conducted at screening to confirm absence of osteoporosis. The primary outcome is the relative change (%) in total bone mineral density of the distal tibia at 12 months post-treatment between the active and placebo groups, as determined via high-resolution peripheral quantitative computed tomography. Secondary outcomes are the effects on immune system modulation and cognition, gut microbiota composition, and musculoskeletal and metabolic functions, with particular emphasis on blood glucose regulation.

CONCLUSIONS

The trial will inform on the efficacy and safety of a synbiotic containing both aerobic and anerobic bacterial strains and a prebiotic fiber on reduction in bone loss and on indices of blood glucose regulation. This trial may pave the way for an exciting field of translational research and be the underpinnings of the prevention strategy of osteoporosis and the management of metabolic dysfunction in postmenopausal women. The trial is registered with clinicaltrials.gov (NCT05348694).

The Association between Bone Mineral Density and Risk of Mortality: A Prospective Cohort Study of 233,397 Taiwanese

PURPOSE

Osteoporosis is an important public health challenge given its high prevalence in western populations and the prevalence has shown an upward trend in recent decades in Asia. However, epidemiological evidence on the association between bone mineral density (BMD) and mortality risk in the Asian population is sparse.

METHODS

The Cox proportional hazards model and cause-specific hazard models were used to investigate the association of BMD with the risk of all-cause mortality and cause-specific mortality.

RESULTS

The present study comprised of 3,332,207 person-years with a median follow-up of 14.6 years. 27,508 participants (15,967 men and 11,541 women) died among 233,397 participants (112,348 men and 121,049 women) during the follow-up period. Compared to those with normal BMD level, both men and women with low BMD had a significantly higher risk of all-cause, cardiovascular disease (CVD), and cancer mortality after adjusting for the covariates. [For men with osteoporosis: all-cause: 1.37 (1.27-1.49); CVD: 1.28 (1.08-1.52); cancer: 1.29 (1.12-1.49); For women with osteoporosis: all-cause: 1.72 (1.63-1.82); CVD: 1.85 (1.64-2.08); cancer: 1.47 (1.35-1.61)]. The P for interactions for BMD with sex were significant for all-cause and CVD mortality. The adverse effects of BMD on the risk of all-cause and CVD were higher in women than in men [men vs. women: all-cause: 1.37 (1.27-1.49) vs. 1.72 (1.63-1.82); CVD: 1.28 (1.08-1.52) vs. 1.85 (1.64-2.08)]. In the nonlinear dose-response analyses, the association between BMD increments and all-cause mortality risk shows an L-shaped pattern in men and a similar U-shaped trend in women (P for non-linear association: <0.001). Likewise, a similar L-shaped association was observed between BMD levels and cancer mortality risk in men.

CONCLUSIONS

Low BMD had an increased risk of all-cause, CVD, and cancer mortality in both men and women. Women had a stronger positive association between low BMD and an increased risk of all-cause and CVD mortality compared to men.

End-to-End Semi-Supervised Opportunistic Osteoporosis Screening Using Computed Tomography

BACKGRUOUND

Osteoporosis is the most common metabolic bone disease and can cause fragility fractures. Despite this, screening utilization rates for osteoporosis remain low among populations at risk. Automated bone mineral density (BMD) estimation using computed tomography (CT) can help bridge this gap and serve as an alternative screening method to dual-energy X-ray absorptiometry (DXA).

METHODS

The feasibility of an opportunistic and population agnostic screening method for osteoporosis using abdominal CT scans without bone densitometry phantom-based calibration was investigated in this retrospective study. A total of 268 abdominal CT-DXA pairs and 99 abdominal CT studies without DXA scores were obtained from an oncology specialty clinic in the Republic of Korea. The center axial CT slices from the L1, L2, L3, and L4 lumbar vertebrae were annotated with the CT slice level and spine segmentation labels for each subject. Deep learning models were trained to localize the center axial slice from the CT scan of the torso, segment the vertebral bone, and estimate BMD for the top four lumbar vertebrae.

RESULTS

Automated vertebra-level DXA measurements showed a mean absolute error (MAE) of 0.079, Pearson's r of 0.852 (P<0.001), and R2 of 0.714. Subject-level predictions on the held-out test set had a MAE of 0.066, Pearson's r of 0.907 (P<0.001), and R2 of 0.781.

CONCLUSION

CT scans collected during routine examinations without bone densitometry calibration can be used to generate DXA BMD predictions.

Geographic variation in bone mineral density and prevalent fractures in the Canadian longitudinal study on aging

Awareness of the prevalence of osteoporosis and fractures across jurisdictions can guide the development of local preventive programs and healthcare policies. We observed geographical variations in total hip bone mineral density and in the prevalence of major osteoporotic fractures across Canadian provinces, which persisted after adjusting for important covariates.

PURPOSE

We aimed to describe sex-specific total hip bone mineral density (aBMD) and prevalent major osteoporotic fractures (MOF) variation between Canadian provinces.

METHODS

We used baseline data from 21,227 Canadians (10,716 women, 10,511 men) aged 50-85 years in the Canadian Longitudinal Study on Aging (CLSA; baseline: 2012-2015). Linear and logistic regression models were used to examine associations between province of residence and total hip aBMD and self-reported MOF, stratified by sex. CLSA sampling weights were used to generate the prevalence and regression estimates.

RESULTS

The mean (SD) age of participants was 63.9 (9.1) years. The mean body mass index (kg/m2) was lowest in British Columbia (27.4 [5.0]) and highest in Newfoundland and Labrador (28.8 [5.3]). Women and men from British Columbia had the lowest mean total hip aBMD and the lowest prevalence of MOF. Alberta had the highest proportion of participants reporting recent falls (12.0%), and Manitoba (8.4%) the fewest (p-value=0.002). Linear regression analyses demonstrated significant differences in total hip aBMD: women and men from British Columbia and Alberta, and women from Manitoba and Nova Scotia had lower adjusted total hip aBMD than Ontario (p-values<0.02). Adjusted odds ratios (95% confidence intervals, CI) for prevalent MOF were significantly lower in women from British Columbia (0.47 [95% CI: 0.32; 0.69]) and Quebec (0.68 [95% CI: 0.48; 0.97]) and in men from British Columbia (0.40 [95% CI:0.22; 0.71]) compared to Ontario (p-values<0.03). Results were similar when adjusting for physical performance measures and when restricting the analyses to participants who reported White race/ethnicity.

CONCLUSION

Geographical variations in total hip aBMD and in the prevalence of MOF between provinces persisted after adjusting for important covariates which suggests an association with unmeasured individual and environmental factors.

Longitudinal association between muscle and bone loss: Results of US and Japanese cohort studies

BACKGROUND

Muscle and bone are physiologically interconnected, but joint changes of muscle and bone with aging, and whether the muscle-bone changes are different by sex and by country has been little studied. We examined longitudinal associations of bone mineral density (BMD) and muscle mass or muscle strength in community-dwelling 65 years or older in the United States and Japan.

METHODS

The present analytic sample included 1129 women and men from the Baltimore Longitudinal Study of Aging (BLSA) (mean age, 74.5 ± 7.5 years; women, 49.8%) and 1998 women and men from the National Institute for Longevity Sciences-Longitudinal Study of Aging (NILS-LSA) (mean age, 70.0 ± 4.5 years; women, 51.4%). Median follow-up was 4.6 (min-max, 0-15.4) years in the BLSA and 4.0 (min-max, 0-13.4) years in the NILS-LSA. We selected visits at which participants had BMD (whole body, pelvic, femoral neck, trochanter, and Ward's triangle BMDs) and muscle mass [appendicular lean mass, (ALM)] measured by DXA scan. In each bone site, we ran cohort-specific bivariate linear mixed-effects models adjusted for baseline age, sex, body height, body weight, fat mass, education year, and smoking status. Race was an additional adjustment in the BLSA. Additionally, we performed sex-specific analyses.

RESULTS

In the BLSA, the rate of change in ALM positively correlated with the rate of change in the whole body (rho = 0.30, P < 0.0001) and pelvic BMD (rho = 0.24, P < 0.0001), but not in trochanter, femoral neck, or Ward's triangle BMD (P > 0.05). In the NILS-LSA, ALM positively correlated with the rate of change in all bone sites (rho ranged from 0.20 to 0.71, P < 0.01). In women, ALM positively correlated with the rate of change in all bone sites in both cohorts (in the NILS-LSA, rho ranged from 0.35 to 0.91, P < 0.01; in the BLSA, rho ranged from 0.26 to 0.56, P < 0.05) except for femoral neck BMD in the BLSA. In men, ALM positively correlated with pelvic, trochanter, and Ward's triangle BMD in the NILS-LSA (rho ranged from 0.45 to 0.68, P < 0.0001), and whole body and trochanter BMD in the BLSA (both, rho = 0.20, P < 0.05).

CONCLUSIONS

Muscle loss co-occurred with bone loss in both cohorts, but the association in the NILS-LSA tended to be stronger than in the BLSA, and the association was higher in women than in men, implying that the association may differ by sex and country.

Longitudinal changes of the femoral bone mineral density from first to third trimester of pregnancy: bone health assessment by means of non-ionizing REMS technology

BACKGROUND

Throughout the pregnancy, there is a substantial transfer of calcium from the maternal skeleton to the fetus, which leads to a transient net reduction of the maternal bone mineral density.

AIMS

To assess longitudinally the changes in the bone mineral density at the femoral neck between the first and third trimester of pregnancy in a cohort of healthy participants using Radiofrequency Echographic Multi Spectrometry (REMS) technology.

METHODS

Prospective, cohort study conducted at the University hospital of Parma, Italy between July 2022 and February 2023. We recruited healthy participants with an uncomplicated singleton pregnancy before 14 completed weeks of gestation. All included participants were submitted to a sonographic examination of the femoral neck to assess the bone mineral density (and the corresponding Z-score values) using REMS at 11-13 and 36-38 weeks of pregnancy. The primary outcome was the change in the bone mineral density values at the maternal femoral neck between the first and third trimester of pregnancy.

RESULTS

Over a period of 7 months, a total of 65 participants underwent bone mineral density measurement at the femoral neck at first and third trimester of the pregnancy using REMS. A significant reduction of the bone mineral density at the femoral neck (0.723 ± 0.069 vs 0.709 ± 0.069 g/cm2; p < 0.001) was noted with a mean bone mineral density change of - 1.9 ± 0.6% between the first and third trimester of pregnancy. At multivariable linear regression analysis, none of the demographic or clinical variables of the study population proved to be independently associated with the maternal bone mineral density changes at the femoral neck.

CONCLUSIONS

Our study conducted on a cohort of healthy participants with uncomplicated pregnancy demonstrates that there is a significant reduction of bone mineral density at femoral neck from early to late gestation.

Computer Vision in Osteoporotic Vertebral Fracture Risk Prediction: A Systematic Review

Osteoporotic vertebral fractures (OVFs) are a significant health concern linked to increased morbidity, mortality, and diminished quality of life. Traditional OVF risk assessment tools like bone mineral density (BMD) only capture a fraction of the risk profile. Artificial intelligence, specifically computer vision, has revolutionized other fields of medicine through analysis of videos, histopathology slides and radiological scans. In this review, we provide an overview of computer vision algorithms and current computer vision models used in predicting OVF risk. We highlight the clinical applications, future directions and limitations of computer vision in OVF risk prediction.

The Prognostic Impact of Preoperative Osteopenia in Patients With Colorectal Cancer

BACKGROUND

Osteopenia, a condition in which bone mineral density is lower than normal, is a noted risk factor that leads to a shortened healthy life expectancy.

OBJECTIVE

To investigate the prognostic impact of preoperative osteopenia in patients with colorectal cancer.

DESIGN

This was a retrospective study.

SETTING

This study was conducted at a university hospital.

PATIENTS

A total of 1086 patients with stage I to III colorectal cancer who underwent curative resection.

MAIN OUTCOME MEASURES

Osteopenia was evaluated with CT. Overall survival, disease-specific survival, and recurrence-free survival were the primary end points.

RESULTS

Osteopenia was identified in 300 patients (27.6%). Compared with the no osteopenia group, the 5-year overall survival (74.0% vs 93.4%, p < 0.001), disease-specific survival (81.6% vs 97.2%, p < 0.001), and recurrence-free survival rates (57.1% vs 88.3%, p < 0.001) were significantly lower in the osteopenia group. Multivariate analyses showed that preoperative osteopenia was significantly associated with worse overall survival (HR: 4.135; 95% CI, 2.963-5.770; p < 0.001), disease-specific survival (HR: 7.673; 95% CI, 4.646-12.675; p < 0.001), and recurrence-free survival (HR: 5.039; 95% CI, 3.811-6.662; p < 0.001). The prognosis of the osteopenia group was poorer than that of the no osteopenia group in every stage: 5-year overall survival (stage I: 89.4% vs 96.9%, p = 0.028; stage II: 76.5% vs 91.9%, p < 0.001; stage III: 56.4% vs 90.8%, p < 0.001) and 5-year recurrence-free survival (stage I: 85.4% vs 96.6%, p = 0.002; stage II: 62.0% vs 86.5%, p < 0.001; stage III: 26.4% vs 80.0%, p < 0.001).

LIMITATIONS

The main limitations are retrospective single-institutional features and races of the study population.

CONCLUSIONS

Preoperative osteopenia could be a strong predictive marker for long-term prognosis in colorectal cancer regardless of stage.

EL IMPACTO PRONSTICO DE LA OSTEOPENIA PREOPERATORIA EN PACIENTES CON CNCER COLORRECTAL

ANTECEDENTES:La osteopenia, una afección en la que la densidad mineral ósea es más baja de lo normal, es un relevante factor de riesgo que conduce a una expectativa menor de vida saludable.OBJETIVO:Investigar el impacto pronóstico de la osteopenia preoperatoria en pacientes con cáncer colorrectal (CCR).DISEÑO:Un estudio retrospectivo.AJUSTE:Estudio realizado en un hospital universitario.PACIENTES:Un total de 1.086 pacientes con CCR en estadio I-III sometidos a una resección curativa.PRINCIPALES MEDIDAS DE RESULTADO:La osteopenia se evaluó con imágenes de tomografía computarizada. La supervivencia global la supervivencia específica de la enfermedad y la supervivencia libre de recurrencia fueron los criterios de valoración primaria.RESULTADOS:Se identificó osteopenia en 300 pacientes (27,6%). En comparación con el grupo sin osteopenia, las tasas de supervivencia global a 5 años (74,0% frente a 93,4%, p < 0,001), supervivencia especifica de la enfermedad (81,6 % frente a 97,2%, p < 0,001) tasas de supervivencia libre de recurrencia (57,1% frente a 88,3%, p < 0,001) fueron significativamente más bajas en el grupo de osteopenia. Los análisis multivariados mostraron que la osteopenia preoperatoria se asoció significativamente con una peor supervivencia global (HR 4,135; IC 95% 2,963-5,770; p < 0,001), supervivencia especifica de la enfermedad (HR 7,673; IC 95% 4,646-12,675; p < 0,001) y tasas de supervivencia libre de recurrencia (HR 5,039; IC 95% 3,811-6,662; p < 0,001). El pronóstico del grupo con osteopenia fue peor que el del grupo sin osteopenia en todos los estadios: supervivencia global a 5 años (estadio I: 89,4% frente a 96,9%, p = 0,028; estadio II: 76,5% frente a 91,9%, p < 0,001; estadio III: 56,4% frente a 90,8%, p < 0,001) y tasas de supervivencia libre de recurrencia a 5 años (estadio I: 85,4% frente a 96,6%, p < 0,002; estadio II: 62,0% frente a 86,5%, p < 0,001; estadio III: 26,4% frente a 80,0%, p < 0,001).LIMITACIONES:Las principales limitaciones son las características retrospectivas de una sola institución y las razas de la población de estudio.CONCLUSIONES:La osteopenia preoperatoria puede ser un fuerte marcador predictivo para el pronóstico a largo plazo en CCR independientemente de la etapa. (Traducción-Dr. Fidel Ruiz Healy ).

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.

Nonalcoholic Fatty Liver Disease Is Associated With Decreased Bone Mineral Density in Adults: A Systematic Review and Meta-Analysis

This systematic review and meta-analysis aimed to investigate the effect of nonalcoholic fatty liver disease (NAFLD) on bone mineral density (BMD) and the risk of osteoporosis and osteoporotic fracture in adults. We searched PubMed, MEDLINE, Embase, CINAHL, Web of Science, Cochrane Library, and Scopus for observational studies published from inception to January 2023 that reported adjusted effect sizes of NAFLD on BMD, osteopenia/osteoporosis, and osteoporotic fracture. The data were synthesized using multilevel and random-effects models. A total of 19 studies were included; of these, nine (21,294 participants) evaluated the effect of NAFLD on BMD, six (133,319 participants) investigated the risk of osteoporosis, and five (227,901 participants) assessed the risk of osteoporotic fracture. This meta-analysis showed that NAFLD was associated with decreased BMD (mean difference -0.019 g/cm2 , 95% confidence interval [CI] -0.036 to -0.002, I2 = 93%) and increased risks of osteoporosis (adjusted risk ratio [RR] = 1.28, 95% CI 1.08 to 1.52, I2 = 84%) and osteoporotic fractures (adjusted RR = 1.17, 95% CI 1.00 to 1.37, I2 = 67%). Subgroup analyses revealed that NAFLD had a significantly detrimental effect on BMD in men and on the BMD of the femoral neck and total hip. Stratified analyses by ethnicity demonstrated that NAFLD was not associated with BMD, osteoporosis, or osteoporotic fracture in non-Asian populations. The publication bias of all included studies was low; however, there was considerable heterogeneity among the studies, warranting a careful interpretation of the findings. Overall, our results suggest that NAFLD is associated with decreased BMD and an increased risk of osteoporosis or osteoporotic fractures. Male sex and the BMD of the femoral neck and total hip may be potential risk factors for decreased BMD in adults with NAFLD. Additionally, ethnic disparities were observed between Asian and non-Asian populations regarding BMD and osteoporotic fractures. © 2023 American Society for Bone and Mineral Research (ASBMR).

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.

Aging and Bone Metabolism

Changes in bone architecture and metabolism with aging increase the likelihood of osteoporosis and fracture. Age-onset osteoporosis is multifactorial, with contributory extrinsic and intrinsic factors including certain medical problems, specific prescription drugs, estrogen loss, secondary hyperparathyroidism, microenvironmental and cellular alterations in bone tissue, and mechanical unloading or immobilization. At the histological level, there are changes in trabecular and cortical bone as well as marrow cellularity, lineage switching of mesenchymal stem cells to an adipogenic fate, inadequate transduction of signals during skeletal loading, and predisposition toward senescent cell accumulation with production of a senescence-associated secretory phenotype. Cumulatively, these changes result in bone remodeling abnormalities that over time cause net bone loss typically seen in older adults. Age-related osteoporosis is a geriatric syndrome due to the multiple etiologies that converge upon the skeleton to produce the ultimate phenotypic changes that manifest as bone fragility. Bone tissue is dynamic but with tendencies toward poor osteoblastic bone formation and relative osteoclastic bone resorption with aging. Interactions with other aging physiologic systems, such as muscle, may also confer detrimental effects on the aging skeleton. Conversely, individuals who maintain their BMD experience a lower risk of fractures, disability, and mortality, suggesting that this phenotype may be a marker of successful aging. © 2023 American Physiological Society. Compr Physiol 13:4355-4386, 2023.

Spine trabecular bone scores and bone mineral density of postmenopausal Taiwanese women

OBJECTIVES

The aims of the study were to determine the mean trabecular bone score (TBS) of postmenopausal Taiwanese women and to analyze the value of TBS in predicting osteoporosis.

METHODS

A total of 1,915 postmenopausal women with lumbar spine and hip bone mineral density (BMD) and spine TBS were enrolled from a single medical center into this study. The women's BMD and TBS were measured using dual x-ray absorptiometry (Discovery Wi; Hologic, Bedford, Mass) and iNsight software (Med-Imaps SASU, Merignac, France), respectively. The women's demographic characteristics; lumbar spine, total hip, and femoral neck BMD; and lumbar spine TBS were recorded, and correlations among the parameters were identified using a 2-tailed Pearson test, in which a P value less than 0.05 was considered statistically significant. We developed simple linear regression models to represent changes related to TBS and performed an analysis of variance on the selected variables.

RESULTS

The average age of the women was 62.5 ± 9.1 years (range, 25.7-93.7 years). The mean TBS was 1.300 ± 0.086 (range, 1.015-1.596). The TBS was weakly and negatively correlated with body mass index ( r = -0.078) and moderately and positively correlated with the lumbar spine BMD ( r = 0.619). The patients' lowest BMD values among those measured at multiple sites revealed a higher rate of osteoporosis (32.5%) than those measured at individual sites. Degraded TBS were noted in 21.2% of the participants, and a combination of BMD and TBS results predicted more individuals (7.8%) at a high risk of fracture than did the BMD result only. The rates of both osteoporosis and degraded TBS increased with age.

CONCLUSIONS

Bone mineral density and TBS can be used in combination to predict osteoporosis in a greater number of postmenopausal Taiwanese women. Because the incidence of osteoporosis is the highest among older women, clinicians should pay careful attention to TBS degradation among older patients without low BMD.

A Mini Review on Osteoporosis: From Biology to Pharmacological Management of Bone Loss

Osteoporosis refers to excessive bone loss as reflected by the deterioration of bone mass and microarchitecture, which compromises bone strength. It is a complex multifactorial endocrine disease. Its pathogenesis relies on the presence of several endogenous and exogenous risk factors, which skew the physiological bone remodelling to a more catabolic process that results in net bone loss. This review aims to provide an overview of osteoporosis from its biology, epidemiology and clinical aspects (detection and pharmacological management). The review will serve as an updated reference for readers to understand the basics of osteoporosis and take action to prevent and manage this disease.

Fracture risk in Asian-Canadian women is significantly over-estimated by the Canadian Association of Radiologists-Osteoporosis Canada risk prediction tool: retrospective cohort study

Fracture risk calculators may not be accurate for all ethnicity groups. The Manitoba bone density registry was used to test the Canadian CAROC tool for predicting fracture risk in Asian-Canadian women. The tool significantly over-estimated fracture risk, suggesting that it may not be ideal for Asian-Canadian patients.

PURPOSE

Health risk prediction tools based on largely White populations may lead to treatment inequity when applied to non-White populations where outcome rates differ. We examined the calibration of the Canadian Association of Radiologists-Osteoporosis Canada (CAROC) fracture risk prediction tool in self-identified Asian-Canadian women.

METHODS

Retrospective cohort study of women over age 50 using the Manitoba BMD Registry. At first BMD, the intake questionnaire collected self-identification of ethnicity and fracture risk factors. 10-year fracture risk was estimated using CAROC and categorized into low, medium, or high fracture risk. Linked administrative databases identified incident osteoporotic fractures. Observed fracture rates were compared between White and Asian-Canadians and compared to the original CAROC risk stratification.

RESULTS

There were 63,632 and 1703 women who self-identified as White-Canadian or Asian-Canadian, respectively, covering approximately 600,000 patient-years follow-up. There were 6588 incident fractures; a similar percentage of patients were assigned to each risk stratum at baseline by CAROC. A progressive rise in 10-year observed fracture rates occurred for each CAROC stratum in the White-Canadian population but much lower fracture rates than predicted in Asian-Canadian patients (p &lt; 0.001). Fracture incidence rate ratios were 1.9-2.6 fold higher in White- vs Asian-Canadian patients for all strata (p &lt; 0.001). In the CAROC moderate and high-risk categories, observed fracture rates in Asian-Canadian patients were typically lower than predicted, indicating poor model calibration.

CONCLUSION

In Asian-Canadian women, observed osteoporosis fracture rates are lower than predicted when using the CAROC tool. Over-estimation of fracture risk may influence shared decision-making discussions.

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.

Prevalence of lactose intolerance and malabsorption among children of two ethnic groups from the urban areas of Malaysia and its relation to calcium intake and bone health status

Lactase insufficiency could develop into lactose intolerance (LI) and disrupt the intake of calcium, which is a core nutrient for bone development in children. However, data regarding the prevalence of LI and bone health status (BHS) among Malaysian children are scarcely reported.

PURPOSE

This study aimed to determine the prevalence of LI and lactose malabsorption (LM) in Malay and Chinese children and examine its relationship with calcium intake (CI) and BHS.

METHODS

A total of 400 children participated in this study. The prevalence of lactose tolerance (LT) was assessed using hydrogen breath test, LT test, and visual analogue scales. Assessment of CI was performed using a 24-h dietary recall interview (24-h DR) and food frequency questionnaire (FFQ). Calcaneal broadband ultrasound attenuation (BUA) was measured using a quantitative ultrasonometer.

RESULTS

The prevalence of LI among Chinese children (37%) was significantly higher (p = 0.002) than among Malay children (22.5%). However, 61.5% of Malay and 54.5% of Chinese children were found to have LM. CI of the children fulfilled 30.5% and 33.9% of the Malaysian recommended CI (1300 mg/day) for 24-h DR and FFQ, respectively. The BUA score of Malay children was significantly higher (p < 0.001) than that of Chinese children. However, LT and CI were not correlated with BHS (p > 0.05, respectively).

CONCLUSIONS

LI was diagnosed among Malay and Chinese children. However, the higher prevalence of LM is rather worrying as it could develop to LI. The prevalence possibly has been worsened by insufficient CI. Thus, effective approaches to increase CI are highly needed as bone development occurs rapidly at this age and is important for the attainment of the optimum peak bone mass during late adolescence.

Relationship between Regular Green Tea Intake and Osteoporosis in Korean Postmenopausal Women: A Nationwide Study

Mixed results have been reported regarding whether habitual tea intake affects bone health. This study investigated the relationship between green tea intake and bone mineral density (BMD) in postmenopausal Korean women. We used data from the Korean National Health and Nutrition Examination Surveys from 2008 to 2011 and divided the participants into three groups according to their frequency of green tea intake over the past 12 months. BMD of the lumbar spine, total femur, and femur neck was measured using dual-energy X-ray absorptiometry. The odds ratios (ORs) and 95% confidence intervals (CIs) of osteoporosis and osteopenia according to green tea consumption were analyzed. Participants who did not consume green tea or consumed less than one cup per day were more likely to have osteopenia of the lumbar spine or femur than those who consumed it once to three times a day (OR 1.81 and 1.85, 95% CI, 1.20–2.71; and 1.23–2.77). Moreover, ORs for osteoporosis were 1.91 (95% CI 1.13–3.23) and 1.82 (95% CI 1.09–3.05) in non-consumers and consumers who drank less than one cup per day, respectively, compared with the reference group. These results support that green tea consumption may have benefits on bone health.

Correlation between Hounsfield unit derived from head, thorax, abdomen, spine and pelvis CT and t-scores from DXA

OBJECTIVES

CT examination can potentially be utilised for early detection of bone density changes with no additional procedure and radiation dose. We hypothesise that the Hounsfield unit (HU) measured from CT images is correlated to the t-scores derived from dual energy X-ray absorptiometry (DXA) in multiple anatomic regions.

MATERIALS & METHODS

Data were obtained retrospectively from all patients who underwent both CT examinations - brain (frontal bone), thorax (T7), abdomen (L3), spine (T7 & L3) or pelvis (left hip) - and DXA between 2014 and 2018 in our centre. To ensure comparability, the period between CT and DXA studies must not exceed one year. Correlations between HU values and t-scores were calculated using Pearson's correlation. Receiver operating characteristic (ROC) curves were generated, and the area under the curve (AUC) was used to determine threshold HU values for predicting osteoporosis.

RESULTS

The inclusion criteria were met by 1043 CT examinations (136 head, 537 thorax, 159 lumbar and 151 left hip). The left hip consistently provided the most robust correlations (r = 0.664-0.708, p < 0.001) and the best AUC (0.875-0.893). Meanwhile, thorax T7 and lumbar L3 showed average correlations (range of r values is 0.497-0.679, p < 0.001, AUC range = 0.680-0.783, 95% CI 0.561-0.922, all p < 0.02) and moderate AUC (0.680-0.783). Frontal bone shows low correlation and weak AUC with r < 0.5, AUC = 0.538-0.655, all p > 0.05.

CONCLUSION

HU values derived from the hip, T7 and L3 provided a good to moderate correlation to t-scores with a good prediction for osteoporosis. The suggested optimal thresholds may be used in clinical settings after external validations are performed.

Best Performance Parameters of HR-pQCT to Predict Fragility Fracture: Systematic Review and Meta-Analysis

Osteoporosis is a systemic skeletal disease characterized by low bone mass and bone structural deterioration that may result in fragility fractures. Use of bone imaging modalities to accurately predict fragility fractures is always an important issue, yet the current gold standard of dual-energy X-ray absorptiometry (DXA) for diagnosis of osteoporosis cannot fully satisfy this purpose. The latest high-resolution peripheral quantitative computed tomography (HR-pQCT) is a three-dimensional (3D) imaging device to measure not only volumetric bone density, but also the bone microarchitecture in a noninvasive manner that may provide a better fracture prediction power. This systematic review and meta-analysis was designed to investigate which HR-pQCT parameters at the distal radius and/or distal tibia could best predict fragility fractures. A systematic literature search was conducted in Embase, PubMed, and Web of Science with relevant keywords by two independent reviewers. Original clinical studies using HR-pQCT to predict fragility fractures with available full text in English were included. Information was extracted from the included studies for further review. In total, 25 articles were included for the systematic review, and 16 articles for meta-analysis. HR-pQCT was shown to significantly predict incident fractures and/or major osteoporotic fractures (MOFs). Of all the HR-pQCT parameters, our meta-analysis revealed that cortical volumetric bone mineral density (Ct.vBMD), trabecular thickness (Tb.Th), and stiffness were better predictors. Meanwhile, HR-pQCT parameters indicated better performance in predicting MOFs than incident fractures. Between the two standard measurement sites of HR-pQCT, the non-weight-bearing distal radius was a more preferable site than distal tibia for fracture prediction. Furthermore, most of the included studies were white-based, whereas very few studies were from Asia or South America. These regions should build up their densitometric databases and conduct related prediction studies. It is expected that HR-pQCT can be used widely for the diagnosis of osteoporosis and prediction of future fragility fractures. © 2021 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Much lower prevalence and severity of radiographic osteoporotic vertebral fracture in elderly Hong Kong Chinese women than in age-matched Rome Caucasian women: a cross-sectional study

INTRODUCTION

Many earlier studies reported that East Asians and Caucasians have similar radiographic osteoporotic vertebral fracture (OVF) prevalence. Since elderly Chinese's osteoporotic hip fracture prevalence is half (or less than half) of that of their age-match Caucasians, we hypothesize that elderly Chinese's OVF prevalence could be only half, or even less than half, of that of their age-match Caucasians.

MATERIALS

Age-matched (mean: 74.1 years; range: 65-87 years) elderly women's radiographs (T4-L5) were from two OVF population-based epidemiological studies conducted in Hong Kong (n = 200) and in Rome (n = 200). All radiographs were double read by one reader in Hong Kong and one reader in Rome. Radiological osteoporotic vertebral deformity (ROVD) classification included no ROVD (grade 0), and ROVDs with < 20%, 20 ~ 25%, ≥ 25% ~ 1/3, ≥ 1/3 ~ 40%, ≥ 40% ~ 2/3, and ≥ 2/3 height loss (grade 1 ~ 6) as well as endplate/cortex fracture (ECF). Spinal deformity index (SDI) was calculated with each vertebra assigned a score of 0, 0.5, 1, 1.5, 2, 2.5, and 3 for no ROVD or ROVDs grade 1 ~ 6.

RESULTS

Seventy-seven (38.5%) Chinese subjects and 123 Italian subjects (61.5%) had ROVD respectively (p < 0.0001). Chinese subjects had ECF in 52 (26%) cases involving 100 vertebrae, while Italian subjects had ECF in 93 (47%) cases involving 230 vertebrae. ROVDs in Italian subjects tended to be more severe (total and mean SDI: 454.5 and 3.71 for Italian, and 212 and 2.72 for Chinese, p < 0.05), more likely to be multiple, more likely to have severe and collapsed grades. The slope of the relationship between age vs. SDI was steeper for the Italian subjects than for the Chinese subjects, suggesting ROVD severity developed faster for aging Italian subjects. A trend suggested earlier onset of ROVD among Italian.

CONCLUSION

OVFs in Chinese women tend to be less common, less severe, and less likely to have multiple fractures.

The Saturation Effect of Body Mass Index on Bone Mineral Density for People Over 50 Years Old: A Cross-Sectional Study of the US Population

Background: Previous studies had revealed that Body Mass Index (BMI) positively affected Bone Mineral Density (BMD). However, an excessively high BMI was detrimental to health, especially for the elderly. Moreover, it was elusive how much BMI was most beneficial for BMD in older adults to maintain.

Objective: To investigate whether there was a BMI saturation effect value that existed to maintain optimal BMD.

Methods: A cross-sectional study was conducted using the datasets of the National Health and Nutrition Examination Survey (NHANES) 2005–2006, 2007–2008, 2009–2010, 2013–2014, and 2017–2018. After adjusting for covariates, an analysis of the association between BMI and BMD in different femoral regions (Total femur, Femoral neck, Trochanter, Intertrochanter, and Ward's triangle) and lumbar spine regions (Total spine, L1, L2, L3, and L4) in the whole population was performed using the multivariate linear regression models, smoothing curve fitting, and saturation effects analysis models. Then, subgroup analyses were performed according to gender, age, and race.

Results: A total of 10,910 participants (5,654 males and 5,256 females) over 50 years were enrolled in this population-based study. Multivariate linear regression analyses in the population older than 50 years showed that BMI was positively associated with femoral BMD and lumbar spine BMD (P < 0.001, respectively). Smoothing curve fitting showed that the relationship between BMI and BMD was not simply linear and that a saturation value existed. The saturation effect analysis showed that the BMI saturation value was 26.13 (kg/m²) in the total femur, 26.82 (kg/m²) in the total spine, and showed site-specificity in L1 (31.90 kg/m²) and L2 (30.89 kg/m²). The saturation values were consistent with the whole participants in males, while there was high variability in the females. BMI saturation values remained present in subgroup analyses by age and race, showing specificity in some age (60–70 years old) groups and in some races.

Conclusions: Our study showed a saturation value association between BMI and BMD for people over 50 years old. Keeping the BMI in the slightly overweight value (around 26 kg/m²) might reduce other adverse effects while obtaining optimal BMD.

First assessment of bone mineral density in healthy pregnant women by means of Radiofrequency Echographic Multi Spectrometry (REMS) technology

OBJECTIVE

The maternal bone structure is the largest calcium reserve for the fetus during pregnancy, and this is claimed to lead to a bone mineral density (BMD) reduction in pregnant women. The primary outcome of the present work was to assess the BMD in a group of healthy pregnant women.

STUDY DESIGN

In this prospective case - control observational study, a non-consecutive group of pregnant women with uncomplicated pregnancy at or >37 weeks were enrolled at the unit of Obstetrics and Gynecology, University of Parma, from February to December 2020. The study subjects were submitted to a sonographic examination of the proximal femur with Radiofrequency Echographic Multi Spectrometry (REMS) technology to quantify the BMD of the femur. The BMD values obtained in the study group were compared with those of a control group of non-pregnant women matched for age, ethnicity and pre-pregnant body mass index (BMI).

RESULTS

Overall, 78 pregnant women at 39.1 ± 1.5 weeks were assessed. Compared with non-pregnant women, the femoral BMD values measured in pregnancy using REMS were significant lower (0.769 ± 0.094 g/cm² vs 0.831 ± 0.101 g/cm², p = 0.0001) with a mean BMD reduction of 8.1%. The femoral neck BMD presented a positive correlation with the pre-pregnant BMI (p = 0.0004) and a negative correlation with the maternal age (p < 0.0001). In addition, a lower femoral neck BMD in Caucasian ethnicity compared with non-Caucasian was noted (p < 0.0001).

CONCLUSION

In this exploratory and proof of concept study, for the first time, a decreased BMD has been objectively demonstrated in pregnant compared with non-pregnant women by means of REMS technology. New studies are required to assess the longitudinal changes of maternal bone density throughout the pregnancy.

The diagnostic value of phase angle, an integrative bioelectrical marker, for identifying individuals with dysmobility syndrome: the Korean Urban-Rural Elderly study

Low phase angle, a non-invasive bioimpedance marker, is associated with elevated odds of dysmobility syndrome and its components. Phase angle (estimated cutoffs: < 4.8° in men; < 4.5° in women) can be used to detect dysmobility syndrome in community-dwelling older adults as a simple, integrative screening tool.

INTRODUCTION

Dysmobility syndrome uses a score-based approach to predict fracture risk that incorporates the concepts of osteoporosis, sarcopenia, and obesity. Low phase angle (PhA), a simple, non-invasive bioelectrical impedance marker, was associated with low lean mass, high fat mass, and poor muscle function. We aimed to investigate the association between PhA and dysmobility syndrome, with the exploration of the diagnostic cutoffs.

METHODS

In a community-dwelling Korean older adult cohort, dysmobility syndrome was defined as the presence of ≥ 3 of the following components: osteoporosis, low lean mass, falls in the preceding year, low grip strength, high fat mass, and poor timed up and go performance.

RESULTS

Among the 1825 participants (mean age 71.6, women 66.7%), subjects were classified into sex-stratified PhA tertiles. The prevalence of dysmobility syndrome increased from the highest PhA tertile group to the lowest (15.50 to 2.45% in men; 33.41 to 12.25% in women, P for trend < 0.001). The mean PhA values decreased as the dysmobility score increased (5.33° to 4.65° in men; 4.76° to 4.39° in women, P for trend < 0.001). Low PhA (cutoff: < 4.8° in men; < 4.5° in women) was associated with twofold elevated odds of dysmobility syndrome after adjusting for age, sex, and conventional risk factors. Low PhA improved the identification of individuals with dysmobility syndrome when added to the conventional risk model (area under the curve, 0.73 to 0.75, P = 0.002).

CONCLUSION

Low PhA was associated with dysmobility syndrome and its components, independent of age, sex, body mass index, nutritional status, and inflammation.

Association of Female Reproductive Factors With Incidence of Fracture Among Postmenopausal Women in Korea

IMPORTANCE

Although estrogen level is positively associated with bone mineral density, there are limited data on the risk of fractures after menopause.

OBJECTIVE

To investigate whether female reproductive factors are associated with fractures among postmenopausal women.

DESIGN, SETTING, AND PARTICIPANTS

This population-based retrospective cohort study used data from the Korean National Health Insurance Service database on 1 272 115 postmenopausal women without previous fracture who underwent both cardiovascular and breast and/or cervical cancer screening from January 1 to December 31, 2009. Outcome data were obtained through December 31, 2018.

EXPOSURES

Information was obtained about reproductive factors (age at menarche, age at menopause, parity, breastfeeding, and exogenous hormone use) by self-administered questionnaire.

MAIN OUTCOMES AND MEASURES

Incidence of any fractures and site-specific fractures (vertebral, hip, and others).

RESULTS

Among the 1 272 115 participants, mean (SD) age was 61.0 (8.1) years. Compared with earlier age at menarche (≤12 years), later age at menarche (≥17 years) was associated with a higher risk of any fracture (adjusted hazard ratio [aHR], 1.24; 95% CI, 1.17-1.31) and vertebral fracture (aHR, 1.42; 95% CI, 1.28-1.58). Compared with earlier age at menopause (<40 years), later age at menopause (≥55 years) was associated with a lower risk of any fracture (aHR, 0.89; 95% CI, 0.86-0.93), vertebral fracture (aHR, 0.77; 95% CI, 0.73-0.81), and hip fracture (aHR, 0.88; 95% CI, 0.78-1.00). Longer reproductive span (≥40 years) was associated with lower risk of fractures compared with shorter reproductive span (<30 years) (any fracture: aHR, 0.86; 95% CI, 0.84-0.88; vertebral fracture: aHR, 0.73; 95% CI, 0.71-0.76; and hip fracture: aHR, 0.87; 95% CI, 0.80-0.95). Parous women had a lower risk of any fracture than nulliparous women (aHR, 0.96; 95% CI, 0.92-0.99). Although breastfeeding for 12 months or longer was associated with a higher risk of any fractures (aHR, 1.05; 95% CI, 1.03-1.08) and vertebral fractures (aHR, 1.22; 95% CI, 1.17-1.27), it was associated with a lower risk of hip fracture (aHR, 0.84; 95% CI, 0.76-0.93). Hormone therapy for 5 years or longer was associated with lower risk of any factures (aHR, 0.85; 95% CI, 0.83-0.88), while use of oral contraceptives for 1 year or longer was associated with a higher risk of any fractures (aHR, 1.03; 95% CI, 1.01-1.05).

CONCLUSIONS AND RELEVANCE

The findings of this cohort study suggest that female reproductive factors are independent risk factors for fracture, with a higher risk associated with shorter lifetime endogenous estrogen exposure. Interventions to reduce fracture risk may be needed for women at high risk, including those without osteoporosis.

Osteoporosis awareness among patients in Singapore (OASIS)-a community hospital perspective

This study examines factors associated with osteoporosis awareness and knowledge using Osteoporosis Prevention and Awareness Tool (OPAAT). Of 410 patients, majority of patients had a OPAAT score < 24 (n = 362, 88.3%). Lower education level (odds ratio (OR) (primary education): 3.63; OR (no formal education): 111.5; p < 0.001) and diabetic patients (OR: 1.67; p = 0.003) were associated with lower OPAAT scores.

INTRODUCTION

Lack of osteoporosis awareness forms a critical barrier to osteoporosis care and has been linked with increased institutionalization, healthcare expenditures, and decreased quality of life. This study aims to identify factors associated with osteoporosis awareness and knowledge among female Singaporeans.

METHODOLOGY

A cross-sectional study was conducted among adult female patients (aged 40 to 90 years old) who were admitted into Outram Community Hospital from April to October 2020. Osteoporosis awareness and knowledge were assessed using interviewer-administered Osteoporosis Prevention and Awareness Tool (OPAAT). High knowledge was defined as a OPAAT score ≥ 24. Multivariate logistical regression analyses were used to identify predictors of low OPAAT scores.

RESULTS

Of 410 patients recruited, their mean age was 71.9 ± 9.5 years old and majority of patients had a OPAAT score < 24 (n = 362, 88.3%). Patients with lower OPAAT scores tended to be older (72.5 ± 9.2 vs 67.5 ± 10.1, p < 0.001), attained lower education level (p < 0.001), and were more likely to live in public housing (92.5% vs 81.5%, p = 0.009). The prevalence of diabetes mellitus was higher in patients with low OPAAT scores (39.2% vs 18.8%, p = 0.006). After adjustment for covariates, lower education level (odds ratio (OR) (primary education): 3.63; OR (no formal education): 11.5; p < 0.05) and patients with diabetes mellitus (OR: 1.67; p = 0.03) were associated with lower OPAAT knowledge scores.

CONCLUSION

Elderly female patients in community hospital have inadequate osteoporosis awareness despite being at risk of fractures. There is a need to address the knowledge gap in osteoporosis, especially among diabetic patients or patients with lower education.

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.

Comparison of Vertebral and Femoral Strength Between White and Asian Adults Using Finite Element Analysis of Computed Tomography Scans

Given non-optimal testing rates for dual-energy X-ray absorptiometry (DXA) and the high use of computed tomography (CT) in some Asian countries, biomechanical computed tomography analysis (BCT)-based bone strength testing, which utilizes previously taken clinical CT scans, may improve osteoporosis testing rates. However, an understanding of ethnic differences in such bone strength measurements between Whites and Asians is lacking, which is an obstacle to clinical interpretation. Using previously taken CT and DXA scans, we analyzed bone strength and bone mineral density (BMD) at the hip and spine in two sex- and age-matched community-based cohorts, aged 40 to 80 years: Whites (Rochester, MN, USA) and Koreans (Seoul, South Korea). For both the spine and femur, the age dependence of bone strength was similar for both groups, White (n = 371; women n = 202, 54.5%) and Korean (n = 396; women n = 199, 50.3%). For both sexes, mean spine strength did not differ between groups, but femur strength was 9% to 14% higher in Whites (p ≤ 0.001), an effect that became non-significant after weight adjustment (p = 0.375). For Koreans of both sexes, the fragile bone strength thresholds for classifying osteoporosis, when derived from regional DXA BMD T-score references, equaled the clinically validated thresholds for Whites (in women and men, femoral strength, 3000 N and 3500 N; vertebral strength 4500 N and 6500 N, respectively). Using these thresholds, classifications for osteoporosis for Koreans based on bone strength versus based on DXA BMD T-scores were consistent (89.1% to 94.4% agreement) at both the hip and spine and for both sexes. The BCT-based, clinically validated bone strength thresholds for Whites also applied to Koreans, which may facilitate clinical interpretation of CT-based bone strength measurements for Koreans. © 2020 American Society for Bone and Mineral Research (ASBMR).

Automated resolution independent method for comparing in vivo and dry trabecular bone

OBJECTIVES

Variation in human trabecular bone morphology can be linked to habitual behavior, but it is difficult to investigate in vivo due to the radiation required at high resolution. Consequently, functional interpretations of trabecular morphology remain inferential. Here we introduce a method to link low- and high-resolution CT data from dry and fresh bone, enabling bone functional adaptation to be studied in vivo and results compared to the fossil and archaeological record.

MATERIALS AND METHODS

We examine 51 human dry bone distal tibiae from Nile Valley and UK and two pig tibiae containing soft tissues. We compare low-resolution peripheral quantitative computed tomography (pQCT) parameters and high-resolution micro CT (μCT) in homologous single slices at 4% bone length and compare results to our novel Bone Ratio Predictor (BRP) method.

RESULTS

Regression slopes between linear attenuation coefficients of low-resolution pQCT images and bone area/total area (BA/TA) of high-resolution μCT scans differ substantially between geographical subsamples, presumably due to diagenesis. BRP accurately predicts BA/TA (R² = .97) and eliminates the geographic clustering. BRP accurately estimates BA/TA in pigs containing soft tissues (R² = 0.98) without requiring knowledge of true density or phantom calibration of the scans.

DISCUSSION

BRP allows automated comparison of image data from different image modalities (pQCT, μCT) using different energy settings, in archeological bone and wet specimens. The method enables low-resolution data generated in vivo to be compared with the fossil and archaeological record. Such experimental approaches would substantially improve behavioral inferences based on trabecular bone microstructure.

Bone Mineral Density in Older U.S. Filipino, Chinese, Japanese, and White Women

BACKGROUND/OBJECTIVES

Bone mineral density (BMD) reference data exist for U.S. White, Black, and Hispanic (Mexican American) populations but not for U.S. Asians. Few studies have compared BMD findings among different U.S. Asian ethnicities.

DESIGN

Retrospective observational study.

SETTING

Large northern California healthcare system.

PARTICIPANTS

Asian and White women aged 50 to 79 years with BMD testing from 1998 to 2017 excluding those with estrogen or osteoporosis treatment, recent fracture, or select disorders affecting skeletal health.

MEASUREMENTS

Femoral neck (FN)-BMD and height data.

METHODS

Differences in FN-BMD were examined by ethnicity and age, comparing Filipino, Chinese, and Japanese women and non-Hispanic White women. Differences in BMD were also examined after adjustment for height.

RESULTS

There were 37,224 Asian women (including 11,147 Filipino, 10,648 Chinese, and 2,519 Japanese) and 115,318 non-Hispanic White women. Mean height was similar among the Asian subgroups and about 6 to 8 cm lower than Whites. Mean FN-BMDs differed by less than 3% for Filipino, Chinese, and Japanese and all were lower than Whites, with smaller Asian-White differences among younger women (<3%; ages 50-59) and larger differences among older women (6-8%; ages 65-79). Adjusting FN-BMD for height reduced White-Asian differences by about 30% to 40%.

CONCLUSION

Mean FN-BMD and height for Filipino, Chinese, and Japanese women were similar but consistently lower than White women, especially among older women. Although Asian-White BMD differences were substantially attenuated after height adjustment; some differences persisted for older women. Future studies should investigate potential age-cohort effects and the extent to which these BMD differences influence fracture risk and clinical care.

Exposure-Safety Analyses Identify Predictors of Change in Bone Mineral Density and Support Elagolix Labeling for Endometriosis-Associated Pain

Elagolix is a novel oral gonadotropin releasing hormone receptor antagonist, that can suppress estradiol in a dose‐dependent manner. It is indicated for management of moderate‐to‐severe pain associated with endometriosis. A population exposure‐response model describing the relationship between elagolix exposure and changes in bone mineral density (BMD) was developed using data from four phase III studies in premenopausal women with endometriosis‐associated pain. Elagolix pharmacokinetic exposure‐dependent changes in BMD were described by an indirect‐response maximum effect (E_max) model through stimulation of bone resorption. African American race, higher body mass index (BMI), and lower type‐I collagen C‐telopeptide concentrations were significantly associated with higher baseline BMD. Higher BMI was significantly associated with higher bone formation rates. Simulations using the final model demonstrated that elagolix 150 mg q.d. dosing for 24 months is predicted to result in −1.45% (−2.04 to −0.814) decrease from baseline in BMD and were used to support corresponding dosing recommendations in the label.

Clinical Pharmacology of Elagolix: An Oral Gonadotropin-Releasing Hormone Receptor Antagonist for Endometriosis

The clinical pharmacology of elagolix was extensively evaluated in clinical studies in healthy subjects and in women with endometriosis. Elagolix pharmacokinetics (PK) show significant population variability, however they are minimally affected by patients' baseline characteristics and demographics, except for clinically relevant extrinsic and intrinsic factors such as coadministrated strong organic anion transporting polypeptide (OATP) 1B1 inhibitors and severe hepatic impairment, which are contraindications for the use of elagolix. These studies enabled a comprehensive understanding of elagolix mechanism of action and the downstream pharmacodynamic (PD) effects on gonadotropin and ovarian hormones, as well as full characterization of the PK/PD (PKPD) relationships of elagolix at various dosages, including the approved 150 mg once daily and 200 mg twice daily dosing regimens for the management of moderate to severe pain associated with endometriosis. Several model-based analyses have contributed to understanding of the benefit-risk profile of elagolix in patients with endometriosis, through characterization of the exposure relationship with responder rates, with changes in bone mineral density over time, as well as the interaction with coadministered drugs. Collectively, these studies and analyses served as supportive evidence for the effectiveness of the approved dosages and provided general dosing instructions of the first approved oral gonadotropin-releasing hormone receptor antagonist.

Estimation and projection about the standardized prevalence of osteoporosis in mainland China

We performed a systematic analysis of the standardized prevalence of osteoporosis in mainland China from 1990 to 2050.

INTRODUCTION

Osteoporosis is the most common bone disease. We aimed to investigate the standardized prevalence of osteoporosis in mainland China at the national and regional levels, with projections until 2050.

METHODS

A comprehensive literature search was performed in PubMed, EMBASE, Cochrane Library, CNKI, Wanfang, and CBM-SinoMed. We constructed resample sets to calculate the standardized prevalence in each study. Multilevel mixed-effects logistic regression was used to estimate the age-specific and sex-specific prevalence. The United Nations Population Division (UNPD) data and regional population data from the fifth and sixth censuses in mainland China were used to estimate and project the national and regional prevalence of osteoporosis.

RESULTS

The standardized prevalence of osteoporosis ranged from 5.04% (2.12~11.34%) to 7.46% (3.13~16.32%) in males aged ≥ 50 years and from 26.28% (15.38~40.40%) to 39.19% (25.74~53.95%) in females aged ≥ 50 years from 1990 to 2050. Moreover, we did not find a significant difference in the standardized prevalence among three geographic regions (Central China, West China, and East China).

CONCLUSION

We found that osteoporosis is a serious public health challenge in mainland China. The findings in our study add insight into the epidemiology of osteoporosis and would be beneficial for the prevention and treatment of osteoporosis in mainland China.

The rate of bone loss slows after 1-2 years of initial antiretroviral therapy: final results of the Strategic Timing of Antiretroviral Therapy (START) bone mineral density substudy

OBJECTIVES

Initial antiretroviral therapy (ART) causes loss of bone mineral density (BMD) over the first 1-2 years. Whether this loss continues with longer therapy is unclear. We determined changes in bone and spine BMD over 5 years in adults receiving immediate or deferred initial ART.

METHODS

In the Strategic Timing of Antiretroviral Therapy (START) BMD substudy, ART-naïve adults with CD4 counts > 500 cells/μL were randomized to immediate or deferred ART. Deferred group participants not yet on ART were offered ART after May 2015. Mean per cent changes in total hip and lumbar spine BMD (measured annually by dual-energy X-ray absorptiometry) were compared between groups using longitudinal mixed models. Fracture rates were also compared between groups for all START participants.

RESULTS

Substudy participants (immediate group, n = 201; deferred group, n = 210; median age 32 years; 80% non-white; 24% female) were followed for a mean 4.5 years until December 2016. In the immediate group, > 96% used ART throughout. In the deferred group, 16%, 58% and 94% used ART at years 1, 3 and 5, respectively. BMD decreased more in the immediate group initially; groups had converged by year 3 at the spine and year 4 at the hip by intent-to-treat (ITT). BMD changes after year 1 were similar in the immediate group and in those off ART in the deferred group [mean difference: spine, 0.03% per year; 95% confidence interval (CI) -0.4, 0.4; P = 0.88; hip, -0.2% per year; 95% CI -0.7, 0.3; P = 0.37]. Fracture incidence did not differ significantly between groups (immediate group, 0.86/100 person-years versus deferred group, 0.85/100 person-years; hazard ratio 1.01; 95% CI 0.76, 1.35; P = 0.98).

CONCLUSIONS

Significant ART-induced bone loss slowed after the first year of ART and became similar to that in untreated HIV infection.

A Systematic Review of Beta Cell Function in Adults of Black African Ethnicity

BACKGROUND

Understanding ethnic differences in beta cell function has important implications for preventative and therapeutic strategies in populations at high risk of type 2 diabetes (T2D). The existing literature, largely drawn from work in children and adolescents, suggests that beta cell function in black African (BA) populations is upregulated when compared to white Europeans (WE).

METHODS

A systematic literature search was undertaken in June 2018 to identify comparative studies of beta cell function between adults (>age 18 years) of indigenous/diasporic BA and WE ethnicity. All categories of glucose tolerance and all methodologies of assessing beta cell function in vivo were included.

RESULTS

41 studies were identified for inclusion into a qualitative synthesis. The majority were studies in African American populations (n = 30) with normal glucose tolerance (NGT)/nondiabetes (n = 25), using intravenous glucose stimulation techniques (n = 27). There were fewer studies in populations defined as only impaired fasting glucose/impaired glucose tolerance (IFG/IGT) (n = 3) or only T2D (n = 3). Although BA broadly exhibited greater peripheral insulin responses than WE, the relatively small number of studies which measured C-peptide to differentiate between beta cell insulin secretion and hepatic insulin extraction (n = 14) had highly variable findings. In exclusively IGT or T2D cohorts, beta cell insulin secretion was found to be lower in BA compared to WE.

CONCLUSIONS

There is inconsistent evidence for upregulated beta cell function in BA adults, and they may in fact exhibit greater deficits in insulin secretory function as glucose intolerance develops.

Type 2 Diabetes and Musculoskeletal Symptoms Among Midlife Women

PURPOSE

The purpose of this study was to describe the association between type 2 diabetes and musculoskeletal symptoms among midlife women from 4 major racial/ethnic groups in the United States.

METHODS

This is a secondary data analysis using the data from 164 participants aged 40 to 60 years of 2 larger survey studies (62 with type 2 diabetes and 102 without type 2 diabetes). In the original studies, the participants completed multiple questionnaires on background characteristics, health status, menopausal status, and musculoskeletal symptoms. The Musculoskeletal Symptom Index for Midlife Women was used to determine the number and severity of musculoskeletal symptoms. For data analysis, independent t tests, Mann-Whitney U tests, and multiple regression analyses were used.

RESULTS

The mean number of musculoskeletal symptoms was significantly higher in women with vs without type 2 diabetes as was the mean severity score. In subgroup analyses, among each menopausal stage and non-Hispanic white women, there were significant differences in the numbers and total severity scores between those with type 2 diabetes and without type 2 diabetes. When background characteristics, health status, and menopausal status were controlled, having diagnosis of type 2 diabetes was positively associated with the numbers and total severity scores of musculoskeletal symptoms.

CONCLUSION

Study findings supported significant associations of type 2 diabetes with musculoskeletal symptoms among midlife women. Further studies are recommended to confirm relationships in larger populations.

Trabecular bone score and bone mineral density reference data for women aged 20-70 years and the effect of local reference data on the prevalence of postmenopausal osteoporosis: a cross-sectional study from Sri Lanka

This paper describes age-specific BMD and TBS data of Sri Lankan women aged 20-70 years. No significant change of TBS and BMDs were seen between 20 and 50 years but a rapid decline was seen between 50 and 70 years. Prevalence of osteoporosis showed a marked difference when local reference data were used instead of manufacture provided data.

INTRODUCTION

It is recommended that country-specific reference data are used when estimating diagnostic and therapeutic thresholds in osteoporosis. This study estimated normative BMD and TBS reference data for women aged 20-70 in Sri Lanka and the effect of local reference data on the diagnosis of osteoporosis among postmenopausal women.

METHODOLOGY

A group of healthy community-dwelling women (n = 355) aged 20-70 was recruited from Galle district in the Southern province in Sri Lanka using stratified random sampling method. They underwent DXA adhering to the manufacturer's protocol and regional BMDs and TBS of the lumbar spine were measured.

RESULTS

The highest mean BMD in the spine (0.928 g/cm²) was seen in 20-29 age group while there was a delay in achieving the peak BMD in the femoral neck (0.818 g/cm²) and total hip (0.962 g/cm²) regions(40-49 years). BMDs showed only a mild change between 20 and 49 years but a rapid decline was seen after 50 years (spine 0.013, femoral neck 0.012, and total hip 0.011 g/cm² per year). The highest TBS was seen in 20-29 age group (1.371) and TBS trend with age was parallel to spine BMD. When the reference data provided by the manufacturer was used, 37% of postmenopausal women were found to have osteoporosis but this value changed to 17.6% when the local reference data were used.

CONCLUSION

We found a significant difference in the prevalence of osteoporosis when the local reference values were used instead of data provided by the manufacturer. However, representative data from more centers and fracture data are required before a recommendation to use local instead of international reference data can be stated.

Ethnic differences in bone mineral density among midlife women in a multi-ethnic Southeast Asian cohort

Chinese Singaporean middle-aged women have significantly lower femoral neck bone mineral density and higher lumbar spine bone mineral density than Malays and Indians, after adjustment for age, body mass index, and height.

PURPOSE

Information regarding mediators of differences in bone mineral density (BMD) among Asian ethnicities are limited. Since the majority of hip fractures are predicted to be from Asia, differences in BMD in Asian ethnicities require further exploration. We compared BMD among the Chinese, Malay, or Indian ethnicities in Singapore, aiming to identify potential mediators for the observed differences.

METHODS

BMD of 1201 women aged 45-69 years was measured by dual-energy X-ray absorptiometry. We examined the associations between ethnicity and BMD at both sites, before and after adjusting for potential mediators measured using standardized questionnaires and validated performance tests.

RESULTS

Chinese women had significantly lower femoral neck BMD than Malay and Indian women. Of the more than 20 variables examined, age, body mass index, and height accounted for almost all the observed ethnic differences in femoral neck BMD between Chinese and Malays. However, Indian women still retained 0.047 g/cm² (95% CI, 0.024, 0.071) higher femoral neck BMD after adjustment, suggesting that additional factors may contribute to the increased BMD in Indians. Although no crude ethnic differences in lumbar spine BMD were observed, adjusted regression model unmasked ethnic differences, wherein Chinese women had 0.061(95% CI, - 0.095, 0.026) and 0.065 (95% CI, - 0.091, 0.038) g/cm² higher lumbar spine BMD compared to Malay and Indian women, respectively.

CONCLUSION

BMD in middle-aged Asian women differ by ethnicity and site. Particular attention should be paid to underweight women of Chinese ethnic origin, who may be at highest risk of osteoporosis at the femoral neck and hence hip fractures.

Bone mineral density correlates with survival after resection of extrahepatic biliary malignancies

BACKGROUND & AIMS

Osteopenia is a condition in which bone mineral density (BMD) is lower than normal, and it is an important determinant of bone fragility. However, the utility of osteopenia in assessing the risks of surgery is unclear. This study investigated the impact of preoperative low BMD on the outcomes in patients undergoing resection of extrahepatic biliary cancers.

METHODS

A retrospective analysis was performed with 181 patients who underwent resections of extrahepatic biliary cancers between 2005 and 2015. Their BMD was measured on preoperative computed tomography images. Overall survival (OS) and recurrence-free survival (RFS) rates were compared according to BMD (normal vs. low), and the prognostic factors after surgery were assessed. Propensity score matching was used to minimize the bias in patient background.

RESULTS

Older age and female were strongly associated with low BMD. These factors were used to construct the propensity score model, which yielded a matched cohort of 52 legs in each group. The OS (21.2% vs. 53.9% at 5 years, p < .001) and RFS (21.8% vs. 64.6% at 5 years, p < .001) rates were significantly lower in patients with low BMD (osteopenia) than in those with normal BMD (non-osteopenia). Multivariable analyses showed that low BMD was an independent factor predictive of poor OS (hazard ratio [HR]: 2.343, 95% confidence interval [CI]: 1.362-4.129, p = .002) and poor RFS (HR: 3.648, 95% CI: 1.986-6.990, p=<.001).

CONCLUSIONS

Preoperative low BMD is closely related to mortality and cancer recurrence after the resection of extrahepatic biliary cancers. BMD screening in patients with cancer should be further highlighted in the oncology field.

Decreasing trend of bone mineral density in US multiethnic population: analysis of continuous NHANES 2005-2014

Studies examining recent bone mineral density (BMD) trends in the US population are limited. In our study, we found that age-adjusted mean BMD among US men and women was stable from 2005 to 2010, but then declined in 2013-2014. We also explored factors associated with decreasing BMD in recent years.

INTRODUCTION

Osteoporosis prevalence in the USA declined between 1988 and 2006, while the declining trend in hip fracture may have plateaued in 2013-2014. We aimed to examine whether there has been a corresponding change in BMD trajectory for the US population.

METHODS

Continuous National Health and Nutrition Examination Survey (NHANES) data from 2005-2006 to 2013-2014 were analyzed to examine BMD trends among US men and women aged 30 years and older and among different race/ethnicity subgroups. ANOVA and Bonferroni adjustments were used to examine the differences in mean BMD, and multiple linear regressions adjusting for potential confounding effects were employed to examine BMD trends.

RESULTS

After age standardization, the mean BMD of the femur neck for the first three NHANES cycles was stable (all p > 0.1) in both men and women, but significantly decreased in 2013-2014, from 0.864 g/cm2 to 0.846 g/cm2 (p = 0.0025) in men and from 0.789 to 0.771 g/cm2 (p = 0.03) in women. The overall mean femur neck BMD in 2013-2014 was significantly lower than that in earlier survey cycles in both men and women, even after adjusting for multiple covariates, including age, race, physical activity, previous fracture, BMI, and other variables. Similar results were observed in subgroup analyses of race and sensitivity analyses.

CONCLUSIONS

Age-adjusted mean BMD decreased in 2013-2014 in both men and women, and this significant decrease was also observed in sensitivity and subgroup analyses. The decreased BMD in 2013-2014 still remained significant even after being adjusted for multiple potentially confounding effects.

Influence of Different Reference Databases on Categorization of Bone Mineral Density: A Study on Rural Postmenopausal Women from Southern India

BACKGROUND AND OBJECTIVES

Currently available DXA (Dual energy X-ray Absorptiometry) scanners utilise bone mineral density (BMD) of Caucasian population to calculate T scores and categorise BMD. We studied the influence of various databases on classification of BMD in south-Indian postmenopausal women aged above 50 years.

METHODOLOGY

This was a cross-sectional study. Hologic DXA scanner was used to estimate BMD at lumbar spine (LS) and femoral neck (FN). T scores of ≤-2.5, -2.4 to -1, -0.9 to +1 were diagnostic of osteoporosis, osteopenia and normal respectively. Three reference databases(Italian, Korean and north Indian) were used to recalculate T scores. The agreement (K=kappa) between manufacturer provided database and the other databases was studied. The impact of different databases in diagnosing osteoporosis in subjects with FN fracture was assessed.

RESULTS

A total of 1956 postmenopausal women with mean (SD) age of 62 (4.3) years and 211 femoral neck(FN) fracture subjects with mean(SD) age of 68 (7.2) years were recruited. In subjects with fracture, osteoporosis at FN was found in 72% with Caucasian, 88% with North Indian, 56% with Italian, and 45% with Korean database. On comparing manufacturer provided database with the other population-specific reference, there was perfect agreement with north Indian (κ = 0.81 [FN], κ = 0.82 [LS]) and good agreement with the Italian database (κ = 0.78 [FN], κ = 0.74 [LS]).

CONCLUSION

North-Indian database identified most of the participants with FN fracture as having osteoporosis and had perfect agreement with the manufacturer's database. Follow up studies will further validate the impact of utilizing this database in clinical practice.

Association between Plasma Pentraxin 3 Levels and Bone Mineral Density in Elderly Koreans: the Dong-gu Study

BACKGROUND

We investigated the association between pentraxin 3 (PTX3), a novel inflammatory marker, and bone mineral density (BMD) in the general Korean population.

METHODS

We selected a sub-cohort of 1,440 subjects (757 men and 683 women) from participants in the community-based Dong-gu Study. The mean age was 66.0 ± 8.1 years for men and 63.7 ± 7.9 years for women. The plasma PTX3 levels were measured using an enzyme-linked immunosorbent assay, and BMD was measured in the femoral neck and lumbar spine using dual-energy X-ray absorptiometry. Linear regression analyses were used to evaluate the association between the plasma PTX3 levels and BMD.

RESULTS

PTX3 was inversely associated with the BMD of the lumbar spine (P = 0.010) and femoral neck (P < 0.001) in men but not in women. For men, the association with the BMD of the femoral neck remained after adjustment for multiple comparison (P = 0.020).

CONCLUSION

This study suggests that PTX3 levels might be inversely associated with BMD in elderly men.

The challenges of diagnosing osteoporosis and the limitations of currently available tools

Dual-energy X-ray absorptiometry (DXA) was the first imaging tool widely utilized by clinicians to assess fracture risk, especially in postmenopausal women. The development of DXA nearly coincided with the availability of effective osteoporosis medications. Although osteoporosis in adults is diagnosed based on a T-score equal to or below − 2.5 SD, most individuals who sustain fragility fractures are above this arbitrary cutoff. This incongruity poses a challenge to clinicians to identify patients who may benefit from osteoporosis treatments. DXA scanners generate 2 dimensional images of complex 3 dimensional structures, and report bone density as the quotient of the bone mineral content divided by the bone area. An obvious pitfall of this method is that a larger bone will convey superior strength, but may in fact have the same bone density as a smaller bone. Other imaging modalities are available such as peripheral quantitative CT, but are largely research tools. Current osteoporosis medications increase bone density and reduce fracture risk but the mechanisms of these actions vary. Anti-resorptive medications (bisphosphonates and denosumab) primarily increase endocortical bone by bolstering mineralization of endosteal resorption pits and thereby increase cortical thickness and reduce cortical porosity. Anabolic medications (teriparatide and abaloparatide) increase the periosteal and endosteal perimeters without large changes in cortical thickness resulting in a larger more structurally sound bone. Because of the differences in the mechanisms of the various drugs, there are likely benefits of selecting a treatment based on a patient’s unique bone structure and pattern of bone loss. This review retreats to basic principles in order to advance clinical management of fragility fractures by examining how skeletal biomechanics, size, shape, and ultra-structural properties are the ultimate predictors of bone strength. Accurate measurement of these skeletal parameters through the development of better imaging scanners is critical to advancing fracture risk assessment and informing clinicians on the best treatment strategy. With this information, a “treat to target” approach could be employed to tailor current and future therapies to each patient’s unique skeletal characteristics.

Association of air particulate pollution with bone loss over time and bone fracture risk: analysis of data from two independent studies

BACKGROUND

Air particulate matter (PM) is a ubiquitous environmental exposure associated with oxidation, inflammation, and age-related chronic disease. Whether PM is associated with loss of bone mineral density (BMD) and risk of bone fractures is undetermined.

METHODS

We conducted two complementary studies of: (i) long-term PM <2.5 μm (PM_2.5) levels and osteoporosis-related fracture hospital admissions among 9.2 million Medicare enrollees of the Northeast/Mid-Atlantic United States between 2003-2010; (ii) long-term black carbon [BC] and PM_2.5 levels, serum calcium homeostasis biomarkers (parathyroid hormone, calcium, and 25-hydroxyvitamin D), and annualized BMD reduction over a 8-year follow-up of 692 middle-aged (46.7±12.3 yrs), low-income BACH/Bone cohort participants.

FINDINGS

In the Medicare analysis, risk of bone fracture admissions at osteoporosis-related sites was greater in areas with higher PM_2.5 levels (Risk ratio [RR] 1.041, 95% Confidence Interval [CI], 1.030, 1.051). This risk was particularly high among low-income communities (RR 1.076; 95% CI, 1.052, 1.100). In the longitudinal BACH/Bone study, baseline BC and PM_2.5 levels were associated with lower serum PTH (Estimate for baseline one interquartile increase in 1-year average BC= -1.16, 95% CI -1.93, -0.38; Estimate for baseline one interquartile increase in 1-year average PM_2.5= -7.39; 95%CI -14.17, -0.61). BC level was associated with higher BMD loss over time at multiple anatomical sites, including femoral neck (-0.08%/year per one interquartile increase; 95% CI -0.14, -0.02%/year) and ultradistal radius (-0.06%/year per one interquartile increase; 95% CI -0.12, -0.01%/year).

INTERPRETATION

Our results suggest that poor air quality is a modifiable risk factor for bone fractures and osteoporosis, especially in low-income communities.

Dual-energy X-ray Absorptiometry

Bone mineral density (BMD) measurement by dual-energy X-ray absorptiometry (DXA) is the most commonly used method to assess fracture risk. DXA utilizes two different energy X-rays to calculate BMD and, by comparison to a young normative database, the T-score. In 1994, the World Health Organization defined osteoporosis based on T-score, changing the paradigm of the field and forever placing DXA measurements in the center of osteoporosis diagnosis. Since then, many large studies have demonstrated the predictive value of BMD by DXA-for every standard deviation decline in BMD, there is a relative risk of 1.5-2.5 for fracture. This predictive ability is similar to how blood pressure can predict myocardial infarction. Limitations of DXA are also important to consider. While BMD by DXA can identify those at risk, there is a significant overlap in the BMD of patients who will and will not fracture. Special considerations are also needed in men and ethnic minority groups. These groups may have different bone size, thus affecting the normative range of BMD, and/or distinct bone structure that affect the association between BMD and fractures. Finally, BMD can be affected by positioning errors or artifacts, including osteoarthritis, fracture, and jewelry. Of course, DXA has tremendous strengths as well-namely its wide availability, its low radiation exposure, and a large body of evidence that relate DXA measurements to fracture risk. For these reasons, DXA remains the cornerstone of fracture assessment now and for the foreseeable future.

Trends in osteoporosis and low bone mass in older US adults, 2005-2006 through 2013-2014

This study examined trends in osteoporosis and low bone mass in older US adults between 2005 and 2014 using bone mineral density (BMD) data from the National Health and Nutrition Examination Survey (NHANES). Osteoporosis and low bone mass appear to have increased at the femur neck but not at the lumbar spine during this period.

INTRODUCTION

Recent preliminary data from Medicare suggest that the decline in hip fracture incidence among older US adults may have plateaued in 2013-2014, but comparable data on BMD trends for this time period are currently lacking. This study examined trends in the prevalence of osteoporosis and low bone mass since 2005 using BMD data from NHANES. The present study also updated prevalence estimates to 2013-2014 and included estimates for non-Hispanic Asians.

METHODS

Femur neck and lumbar spine BMD by DXA were available for 7954 adults aged 50 years and older from four NHANES survey cycles between 2005-2006 and 2013-2014.

RESULTS

Significant trends (quadratic or linear) were observed for the femur neck (mean T-score and osteoporosis in both sexes; low bone mass in women) but not for the lumbar spine. The trend in femur neck status was somewhat U-shaped, with prevalences being most consistently significantly higher (by 1.1-6.6 percentage points) in 2013-2014 than 2007-2008. Adjusting for changes in body mass index, smoking, milk intake, and physician's diagnosis of osteoporosis between surveys did not change femur neck trends. In 2013-2014, the percent of older adults with osteoporosis was 6% at the femur neck, 8% at the lumbar spine, and 11% at either site.

CONCLUSIONS

There was some evidence of a decline in femur neck BMD between 2005-2006 and 2013-2014, but not in lumbar spine BMD. Changes in the risk factors that could be examined did not explain the femur neck BMD trends.

Prevention of postmenopausal osteoporosis in Chinese women: a 5-year, double-blind, randomized, parallel placebo-controlled study

OBJECTIVES

To observe the effectiveness and safety of menopause-related hormone therapy (MHT) to prevent bone loss in Chinese women during the menopausal transition and early menopause, as well as to evaluate the effects of 5-year MHT on overall health to add Level I evidence for the prevention of osteoporosis using MHT.

DESIGN

This clinical study was a prospective, double-blind, randomized, parallel placebo-controlled study. Chinese women in the menopausal transition and early menopause were randomly allocated to the MHT group or the placebo group. All subjects received a 5-year intervention. The effectiveness of MHT for bone mineral density (BMD) and bone metabolism and the safety of MHT in relation to glycolipid metabolism, breast cancer, and cardiovascular disease were studied.

RESULTS

In the MHT group, women in both transition and early menopause showed a significant increase in lumbar and femoral neck BMD after the 1st year of therapy; BMD tended to decrease in the 3rd year but ultimately was sustained at stable levels that were near the baseline levels. In the placebo group, BMD decreased at both sites. Metabolism indexes and breast ultrasound examination findings did not differ significantly between the MHT and placebo groups. Three cases of breast cancer and three cases of cardiovascular disease were diagnosed during follow-up. One breast cancer case and two cardiovascular disease cases occurred in the MHT group.

CONCLUSIONS

Five-year sequential therapy with estrogen and progesterone can increase or maintain the BMD of women in their menopausal transition and early menopause. This regimen had no negative effect on glycolipid metabolism and did not increase the risk of breast cancer or cardiovascular events.

Use of Selective Serotonin Reuptake Inhibitors and Risk of Hip Fracture in the Elderly: A Case-Control Study in Taiwan

BACKGROUND

This population based study investigated the relationship between use of selective serotonin reuptake inhibitors (SSRIs) and hip fractures in the elderly in Taiwan.

METHODS

Analysis of a random sample of 1 million insurance enrollees' data identified 4,891 patients with newly diagnosed hip fractures and 4,891 controls without hip fracture between 2000 and 2011. Both cases and controls were ≥65 years of age and were matched by sex, age, comorbidities, and index year of hip fracture diagnosis. Patients were considered current SSRI users if their last SSRI tablet was taken ≤7 days before the hip fracture diagnosis. Late use of SSRIs was defined as taking the last SSRI tablet ≥8 days before the hip fracture diagnosis. Non-SSRI users comprised individuals who never had an SSRI prescription. Odds ratios (ORs) and 95% confidence intervals (CIs) for hip fracture associated with SSRI use was estimated by multivariate unconditional logistic regression.

RESULTS

After adjustment for covariants, multivariate regression analysis showed that the adjusted OR of hip fracture was 2.17 for current SSRI users (95% CI: 1.60-2.93) compared with those who never used SSRIs. The adjusted OR was 1.11 for individuals with late use of SSRIs (95% CI: 0.96-1.28) and was not significant.

CONCLUSIONS

Current use of SSRIs was associated with a 2.17-fold increase in the odds of hip fracture in the elderly in Taiwan. Clinicians should consider the possibility of SSRI-associated hip fracture among old people currently taking SSRIs.