QCT Volumetric Bone Mineral Density and Vascular and Valvular Calcification: The Framingham Study

AI-based opportunistic quantitative image analysis of lung cancer screening CTs to reduce disparities in osteoporosis screening

Osteoporosis is underdiagnosed, especially in ethnic and racial minorities who are thought to be protected against bone loss, but often have worse outcomes after an osteoporotic fracture. We aimed to determine the prevalence of osteoporosis by opportunistic CT in patients who underwent lung cancer screening (LCS) using non-contrast CT in the Northeastern United States. Demographics including race and ethnicity were retrieved. We assessed trabecular bone and body composition using a fully-automated artificial intelligence algorithm. ROIs were placed at T12 vertebral body for attenuation measurements in Hounsfield Units (HU). Two validated thresholds were used to diagnose osteoporosis: high-sensitivity threshold (115-165 HU) and high specificity threshold (<115 HU). We performed descriptive statistics and ANOVA to compare differences across sex, race, ethnicity, and income class according to neighborhoods' mean household incomes. Forward stepwise regression modeling was used to determine body composition predictors of trabecular attenuation. We included 3708 patients (mean age 64 ± 7 years, 54 % males) who underwent LCS, had available demographic information and an evaluable CT for trabecular attenuation analysis. Using the high sensitivity threshold, osteoporosis was more prevalent in females (74 % vs. 65 % in males, p < 0.0001) and Whites (72 % vs 49 % non-Whites, p < 0.0001). However, osteoporosis was present across all races (38 % Black, 55 % Asian, 56 % Hispanic) and affected all income classes (69 %, 69 %, and 91 % in low, medium, and high-income class, respectively). High visceral/subcutaneous fat-ratio, aortic calcification, and hepatic steatosis were associated with low trabecular attenuation (p < 0.01), whereas muscle mass was positively associated with trabecular attenuation (p < 0.01). In conclusion, osteoporosis is prevalent across all races, income classes and both sexes in patients undergoing LCS. Opportunistic CT using a fully-automated algorithm and uniform imaging protocol is able to detect osteoporosis and body composition without additional testing or radiation. Early identification of patients traditionally thought to be at low risk for bone loss will allow for initiating appropriate treatment to prevent future fragility fractures. CLINICALTRIALS.GOV IDENTIFIER: N/A.

Association between bone mineral density and coronary plaque burden in patients with coronary artery disease: a cross-sectional study using quantitative computed tomography

PURPOSE

To evaluate the association between osteoporosis and coronary calcification and coronary plaque burden in patients with atherosclerosis and coronary artery disease (CAD).

METHODS

This study included 290 men and 177 postmenopausal women with angiography-confirmed atherosclerosis or CAD who underwent chest multidetector row computed tomography covering L1-L2 between September 2020 and October 2021. Quantitative computed tomography was used to measure the lumbar vertebra's bone mineral density (BMD). The coronary artery calcium score (CACS) and total coronary plaque burden were quantified using the Agatston and modified Gensini scores, respectively. Associations between BMD and CACS and modified Gensini scores were assessed using multivariate regression analysis. Lasso regression was used in model selection.

RESULTS

In men, BMD was inversely associated with CACS [ β  = -0.24; 95% confidence interval (CI), -0.35 to -0.13; P  < 0.001) and coronary artery calcification (CAC) presence [odds ratio (OR) = 0.71; 95% CI, 0.52-0.96; P  = 0.03) in the unadjusted model. After adjusting for age, modified Gensini score, prior percutaneous coronary intervention and hypertension, BMD was inversely associated with CACS ( β  = -0.11; 95% CI, -0.22 to -0.01; P  = 0.04). In postmenopausal women, BMD was inversely associated with CACS ( β  = -0.24; 95% CI, -0.39 to 0.10; P  < 0.001) and CAC presence (OR = 0.66; 95% CI, 0.47-0.92; P  = 0.01) in the unadjusted model but no other models ( P  > 0.05). In both sexes, BMD did not correlate with the modified Gensini score or CAD prevalence (all P  > 0.05).

CONCLUSION

In patients with coronary atherosclerosis and CAD, BMD of the lumbar vertebra correlated inversely with CACS in men but not postmenopausal women. Additionally, BMD did not correlate with the modified Gensini score in both sexes.

Novel Biomarkers of Bone Metabolism

Bone represents a metabolically active tissue subject to continuous remodeling orchestrated by the dynamic interplay between osteoblasts and osteoclasts. These cellular processes are modulated by a complex interplay of biochemical and mechanical factors, which are instrumental in assessing bone remodeling. This comprehensive evaluation aids in detecting disorders arising from imbalances between bone formation and reabsorption. Osteoporosis, characterized by a reduction in bone mass and strength leading to heightened bone fragility and susceptibility to fractures, is one of the more prevalent chronic diseases. Some epidemiological studies, especially in patients with chronic kidney disease (CKD), have identified an association between osteoporosis and vascular calcification. Notably, low bone mineral density has been linked to an increased incidence of aortic calcification, with shared molecules, mechanisms, and pathways between the two processes. Certain molecules emerging from these shared pathways can serve as biomarkers for bone and mineral metabolism. Detecting and evaluating these alterations early is crucial, requiring the identification of biomarkers that are reliable for early intervention. While traditional biomarkers for bone remodeling and vascular calcification exist, they suffer from limitations such as low specificity, low sensitivity, and conflicting results across studies. In response, efforts are underway to explore new, more specific biomarkers that can detect alterations at earlier stages. The aim of this review is to comprehensively examine some of the emerging biomarkers in mineral metabolism and their correlation with bone mineral density, fracture risk, and vascular calcification as well as their potential use in clinical practice.

Bone-derived PDGF-BB drives brain vascular calcification in male mice

Brain vascular calcification is a prevalent age-related condition often accompanying neurodegenerative and neuroinflammatory diseases. The pathogenesis of large-vessel calcifications in peripheral tissue is well studied, but microvascular calcification in the brain remains poorly understood. Here, we report that elevated platelet-derived growth factor BB (PDGF-BB) from bone preosteoclasts contributed to cerebrovascular calcification in male mice. Aged male mice had higher serum PDGF-BB levels and a higher incidence of brain calcification compared with young mice, mainly in the thalamus. Transgenic mice with preosteoclast-specific Pdgfb overexpression exhibited elevated serum PDGF-BB levels and recapitulated age-associated thalamic calcification. Conversely, mice with preosteoclast-specific Pdgfb deletion displayed diminished age-associated thalamic calcification. In an ex vivo cerebral microvascular culture system, PDGF-BB dose-dependently promoted vascular calcification. Analysis of osteogenic gene array and single-cell RNA-Seq (scRNA-Seq) revealed that PDGF-BB upregulated multiple osteogenic differentiation genes and the phosphate transporter Slc20a1 in cerebral microvessels. Mechanistically, PDGF-BB stimulated the phosphorylation of its receptor PDGFRβ (p-PDGFRβ) and ERK (p-ERK), leading to the activation of RUNX2. This activation, in turn, induced the transcription of osteoblast differentiation genes in PCs and upregulated Slc20a1 in astrocytes. Thus, bone-derived PDGF-BB induced brain vascular calcification by activating the p-PDGFRβ/p-ERK/RUNX2 signaling cascade in cerebrovascular cells.

Cost-Effectiveness of Osteoporosis Opportunistic Screening Using Computed Tomography in China

OBJECTIVES

Underutilization and insufficient availability of dual-energy X-ray absorptiometry (DXA) in diagnosing osteoporosis in China could be changed by adopting unindicated quantitative computed tomography. We aimed to assess the cost-effectiveness of quantitative computed tomography (QCT) as a screening tool for osteoporosis in China.

METHODS

A Markov microsimulation model was developed to assess the long-term costs and quality-adjusted life-years (QALYs) saved associated with 2 examinations as opportunistic screening for osteoporosis in a general population without prior histories of fracture. The diagnostic performance of both examinations was incorporated into the model. In lifetime modeling, opportunistically screened people may face the risk of experiencing hip, vertebral, and wrist fractures depending on their osteoporosis, age, and sex. Model parameters were informed by published literature.

RESULTS

The base-case result showed that QCT was associated with higher costs ($6054 vs $5883) and higher benefits (10.081 vs 10.071 QALYs) in comparison with DXA, making QCT a cost-effective option for opportunistic screening (incremental cost-effectiveness ratio of US $16 430/QALY). Screening with QCT led to fewer fractures over the lifetime simulation: for every 10 000 people screened, 129 fractures (32 hip, 78 vertebral, and 19 wrist fractures) could be avoided because of the early initiation of antiosteoporotic treatment.

CONCLUSIONS

Using QCT to screen people for osteoporosis is more cost-effective than standard practice in China, where access to DXA is minimal. This finding could support opportunistic osteoporosis screening using QCT in other countries with similar status.

Vascular deficits contributing to skeletal fragility in type 1 diabetes

Over 1 million Americans are currently living with T1D and improvements in diabetes management have increased the number of adults with T1D living into later decades of life. This growing population of older adults with diabetes is more susceptible to aging comorbidities, including both vascular disease and osteoporosis. Indeed, adults with T1D have a 2- to 3- fold higher risk of any fracture and up to 7-fold higher risk of hip fracture compared to those without diabetes. Recently, diabetes-related vascular deficits have emerged as potential risks factors for impaired bone blood flow and poor bone health and it has been hypothesized that there is a direct pathophysiologic link between vascular disease and skeletal outcomes in T1D. Indeed, microvascular disease (MVD), one of the most serious consequences of diabetes, has been linked to worse bone microarchitecture in older adults with T1D compared to their counterparts without MVD. The association between the presence of microvascular complications and compromised bone microarchitecture indicates the potential direct deleterious effect of vascular compromise, leading to abnormal skeletal blood flow, altered bone remodeling, and deficits in bone structure. In addition, vascular diabetic complications are characterized by increased vascular calcification, decreased arterial distensibility, and vascular remodeling with increased arterial stiffness and thickness of the vessel walls. These extensive alterations in vascular structure lead to impaired myogenic control and reduced nitric-oxide mediated vasodilation, compromising regulation of blood flow across almost all vascular beds and significantly restricting skeletal muscle blood flow seen in those with T1D. Vascular deficits in T1D may very well extend to bone, compromising skeletal blood flow control, and resulting in reduced blood flow to bone, thus negatively impacting bone health. Indeed, several animal and ex vivo human studies report that diabetes induces microvascular damage within bone are strongly correlated with diabetes disease severity and duration. In this review article, we will discuss the contribution of diabetes-induced vascular deficits to bone density, bone microarchitecture, and bone blood flow regulation, and review the potential contribution of vascular disease to skeletal fragility in T1D.

Sex Differences in Extensive Mitral Annular Calcification With Associated Mitral Valve Dysfunction

Mitral annular calcification (MAC)-related mitral valve (MV) dysfunction is an increasingly recognized entity, which confers a high burden of morbidity and mortality. Although more common among women, there is a paucity of data regarding how the phenotype of MAC and the associated adverse clinical implications may differ between women and men. A total of 3,524 patients with extensive MAC and significant MAC-related MV dysfunction (i.e., transmitral gradient ≥3 mm Hg) were retrospectively analyzed from a large institutional database, with the goal of defining gender differences in clinical and echocardiographic characteristics and the prognostic importance of MAC-related MV dysfunction. We stratified patients into low- (3 to 5 mm Hg), moderate- (5 to 10 mm Hg), and high- (≥10 mm Hg) gradient groups and analyzed the gender differences in phenotype and outcome. The primary outcome was all-cause mortality, assessed using adjusted Cox regression models. Women represented the majority (67%) of subjects, were older (79.3 ± 10.4 vs 75.5 ± 10.9 years, p <0.001) and had a lower burden of cardiovascular co-morbidities than men. Women had higher transmitral gradients (5.7 ± 2.7 vs 5.3 ± 2.6 mm Hg, p <0.001), more concentric hypertrophy (49% vs 33%), and more mitral regurgitation. The median survival was 3.4 years (95% confidence interval 3.0 to 3.6) among women and 3.0 years (95% confidence interval 2.6 to 4.5) among men. The adjusted survival was worse among men, and the prognostic impact of the transmitral gradient did not differ overall by gender. In conclusion, we describe important gender differences among patients with MAC-related MV dysfunction and show worse adjusted survival among men; although, the adverse prognostic impact of the transmitral gradient was similar between men and women.

The Association of Coronary Artery Calcium Score and Osteoporosis in Postmenopausal Women: A Cross-Sectional Study

BACKGROUND

The association between osteoporosis, a common metabolic bone disorder, and atherosclerosis has been reported in different studies. In this study, we aimed to investigate the association between the coronary artery calcium score (CACS) and bone mineral density (BMD) at different sites and bone biomarkers in postmenopausal women.

METHODS

A total of 184 participants were enrolled in this study. The CACS and BMD at different sites, including the spinal, total hip, and femoral neck, were measured using computed tomography angiography and dual energy X-ray absorptiometry, respectively. Serum levels of osteocalcin, β-C-terminal telopeptide (β-CTX), parathyroid hormone, and 25-hydroxy-vitamin D were measured.

RESULTS

A negative association between CACS and bone biomarker levels (osteocalcin, P=0.021; β-CTX, P=0.013) was noted. The univariable model showed an association between CACS and osteoporosis of the femoral neck (P=0.03). It was found that with an increase of 10 U in CACS, the odds of osteoporosis at the femoral neck escalates by 2% (odds ratio=1.02, 95% confidence interval, 1.002-1.03) using the multivariate logistic regression model, while such an association with osteoporosis could not be found at the spinal site. The best cutoff point of the calcium score was estimated to be 127.

CONCLUSIONS

The results suggest that in postmenopausal women, coronary atherosclerosis is independently associated with osteoporosis of the femoral neck, but such an association could not be detected with spinal osteoporosis. The importance of screening for osteoporosis in patients with cardiovascular disease and the implications of preventive measures in the primary care setting were highlighted considering the common risk factors.

Association of Abdominal Aortic Calcification with Peripheral Quantitative Computed Tomography Bone Measures in Older Women: The Perth Longitudinal Study of Ageing Women

We have previously shown that abdominal aortic calcification (AAC), a marker of advanced atherosclerotic disease, is weakly associated with reduced hip areal bone mineral density (aBMD). To better understand the vascular-bone health relationship, we explored this association with other key determinants of whole-bone strength and fracture risk at peripheral skeletal sites. This study examined associations of AAC with peripheral quantitative computed tomography (pQCT)-assessed total, cortical and trabecular volumetric BMD (vBMD), bone structure and strength of the radius and tibia among 648 community-dwelling older women (mean ± SD age 79.7 ± 2.5 years). We assessed associations between cross-sectional (2003) and longitudinal (progression from 1998/1999-2003) AAC assessed on lateral dual-energy X-ray absorptiometry (DXA) images with cross-sectional (2003) and longitudinal (change from 2003 to 2005) pQCT bone measures at the 4% radius and tibia, and 15% radius. Partial Spearman correlations (adjusted for age, BMI, calcium treatment) revealed no cross-sectional associations between AAC and any pQCT bone measures. AAC progression was not associated with any bone measure after adjusting for multiple comparisons, despite trends for inverse correlations with total bone area at the 4% radius (r_s =  - 0.088, p = 0.044), 4% tibia (r_s =  - 0.085, p = 0.052) and 15% radius (r_s =  - 0.101, p = 0.059). Neither AAC in 2003 nor AAC progression were associated with subsequent 2-year pQCT bone changes. ANCOVA showed no differences in bone measures between women with and without AAC or AAC progression, nor across categories of AAC extent. Collectively, these finding suggest that peripheral bone density and structure, or its changes with age, are not associated with central vascular calcification in older women.

Relationship between ectopic calcifications and bone fragility depicted on computed tomography scan in 70 patients with systemic sclerosis

Background

A higher risk of osteoporotic fracture was described in systemic sclerosis patients than in healthy patients.

Objective

To evaluate the relation between osteoporotic fracture risk measured by the scanographic bone attenuation coefficient of the first lumbar vertebra (SBAC-L1) on computed tomography (CT) scan and the presence of ectopic calcifications: vascular, valvular and spinal.

Methods

This monocentric retrospective study was performed on patients followed between 2000 and 2014 at Nancy University Hospital. Systemic sclerosis patients, according to ACR/EULAR 2013 criteria, followed from 2000 to 2014 and who underwent, during their follow-up, a CT including the first lumbar vertebra were included. The SBAC-L1 was measured with a threshold set at 145 Hounsfield units (HU). Vascular and spinal calcifications were studied on CT. For vascular calcifications, the Agatston score was used. Valvular calcifications were studied on echocardiography.

Results

A total of 70 patients were included (mean age: 62.3 (±15.6) years, women 88.5%). The mean SBAC-L1 was 157.26 (±52.1) HU, and 35 patients (50%) presented an SBAC-L1 ⩽ 145 HU. The reproducibility of the calcification evaluation was good, with kappa coefficients varying between 0.63 and 1. In univariate analysis, spinal and vascular calcifications were associated with an SBAC-L1 ⩽ 145 HU, with ORs of 13.6 (1.6-113.3) and 8 (95%CI: 2.5-25.5), respectively. In multivariate analysis, the SBAC-L1 was not associated with the presence of any ectopic calcifications. The SBAC-L1 decreased with age (p = 0.0001).

Conclusion

Patients with systemic sclerosis with an SBAC-L1 ⩽ 145 HU were older, but they did not have more ectopic calcification.

Trial registration

The ethics committee of Nancy Hospital agreed with this study (referral file number 166). This study was designed in accordance with the general ethical principles outlined in the Declaration of Helsinki.

Skeletal and extraskeletal disorders of biomineralization

The physiological process of biomineralization is complex and deviation from it leads to a variety of diseases. Progress in the past 10 years has enhanced understanding of the genetic, molecular and cellular pathophysiology underlying these disorders; sometimes, this knowledge has both facilitated restoration of health and clarified the very nature of biomineralization as it occurs in humans. In this Review, we consider the principal regulators of mineralization and crystallization, and how dysregulation of these processes can lead to human disease. The knowledge acquired to date and gaps still to be filled are highlighted. The disorders of mineralization discussed comprise a broad spectrum of conditions that encompass bone disorders associated with alterations of mineral quantity and quality, as well as disorders of extraskeletal mineralization (hyperphosphataemic familial tumoural calcinosis). Included are disorders of alkaline phosphatase (hypophosphatasia) and phosphate homeostasis (X-linked hypophosphataemic rickets, fluorosis, rickets and osteomalacia). Furthermore, crystallopathies are covered as well as arterial and renal calcification. This Review discusses the current knowledge of biomineralization derived from basic and clinical research and points to future studies that will lead to new therapeutic approaches for biomineralization disorders.

Relationship of abdominal aortic calcification with lumbar vertebral volumetric bone mineral density assessed by quantitative computed tomography in maintenance hemodialysis patients

INTRODUCTION

This cross-sectional study aimed to investigate the relationship between abdominal aortic calcification (AAC), which is a marker of vascular calcification, and volumetric bone mineral density (vBMD) by quantitative computed tomography (QCT) in maintenance hemodialysis (MHD) patients.

METHODS

All participants underwent lumbar vertebral vBMD measurement by QCT. Eight cross-sections were extracted sequentially and analyzed by ImageJ software to obtain the ratio of the calcified area to the abdominal aortic area (the calcification ratio). The AAC score was determined by the sum of the calcification ratios. The relationship between AAC and vBMD was analyzed using multivariate logistic regression.

RESULTS

Ninety MHD patients (58.89% male) with a mean age of 63.43 (standard deviation [SD] = 13.20) years were included in the study. AAC was present (AAC score > 0) in 93.33% of the patients. The 75th percentile of the AAC score corresponding to 119 was used as the cutoff point between the mild and severe groups. After full adjustment in the logistic model, AAC was found to be inversely associated with vBMD (odds ratio [OR], 0.970; 95% confidence interval [CI], 0.944 to 0.996; P = 0.025), and patients with osteoporosis had a significantly higher risk of severe AAC than those with normal bone mass (OR, 14.498; 95% CI, 1.507 to 139.486; P = 0.021). The independent inverse association was still stable after adjusting for variables measured at different time periods and using different cutoff points of the AAC score.

CONCLUSION

There was an independent inverse association between AAC and vBMD, and osteoporosis was significantly associated with severe AAC in patients with MHD.

Bone mineral density and long-term progression of aortic valve and mitral annular calcification: The Multi-Ethnic Study of Atherosclerosis

BACKGROUND AND AIMS

Bone and mineral metabolism has been implicated in the pathophysiology of cardiac valve calcification. Whether bone demineralization, a common aging-related disorder, promotes calcific valve disease remains uncertain. We tested the hypothesis that low bone mineral density (BMD) is associated with greater incidence/progression of cardiac valve calcification in the Multi-Ethnic Study of Atherosclerosis.

METHODS

Using linear mixed-effects models, we related baseline measurement of BMD of the thoracic vertebrae by computed tomography (CT) in 6768 participants to serial CT assessments of aortic valve calcification (AVC) and mitral annular calcification (MAC) obtained over a >10-year period.

RESULTS

After multivariable adjustment, lower BMD (per SD decrement) was associated with accelerated increase in AVC over time in women (0.76 [95% CI 0.42,1.09] Agatston -units [AU]/year) and men (1.41 [95% CI 0.48,2.33] AU/year), as well as for MAC in women (3.22 [95% CI 1.16,5.28] AU/year) and men (3.59 [95% CI 2.09,5.09] AU/year). Significant effect modification was observed, with more pronounced BMD-related acceleration of AVC and MAC progression in older or white participants of one or both sexes, as well as by estimated glomerular filtration rate, though the latter differed by sex for AVC and MAC.

CONCLUSIONS

In this multi-ethnic cohort, low thoracic BMD was significantly, but modestly, associated with increased AVC and MAC progression. This suggests that altered bone mineral metabolism does not have a major impact on calcific valve disease in the general population, but the possibility of a more meaningful influence in higher-risk individuals with osteoporosis will require further investigation.

High Cardiovascular Risk in Older Men with Poor Bone Microarchitecture-The Prospective STRAMBO Study

Data on the association between bone microarchitecture and cardiovascular disease (CVD) in men are scarce. We studied the link of bone microarchitecture and areal bone mineral density (aBMD) with the risk of major adverse coronary event (MACE) in a cohort of men aged 60 to 87 years followed prospectively for 8 years. At baseline, aBMD was measured using a Hologic Discovery-A device. Bone microarchitecture was assessed at distal radius and tibia by high-resolution peripheral quantitative computed tomography (XtremeCT Scanco device). During the study, 53 men had incident MACE. The analyses were adjusted for confounders related to bone and CVD. In 813 men (53 MACEs), higher aBMD at the lumbar spine, hip, whole body, and radius was associated with lower risk of MACE (hazard ratio [HR] = 0.44-0.71/SD, p < .025 to < .001). In 745 men having valid distal radius scan (47 MACEs), higher cortical density (Ct.BMD) and higher cortical thickness (Ct.Th^d ) were associated with lower risk of MACE. This risk was higher in men in the lowest quintile of cortical measures versus the four upper quintiles combined (Ct.BMD: HR = 2.12, 95% confidence interval [CI] 1.08-4.17, p < .025). Findings were similar in 779 men having valid distal tibia scan (48 MACEs). At both sites, higher estimated stiffness and higher failure load were associated with a lower risk of MACE. The risk of MACE was higher in men in the lowest quintile of the measures of bone strength versus four upper quintiles jointly (distal radius stiffness: HR = 2.46, 95% CI 1.27-4.74, p < .01). Similar results were obtained in 638 men without prior fragility fracture and in 689 men without ischemic heart disease at baseline. Thus, in older men followed prospectively for 8 years, higher aBMD, preserved cortical bone status, and higher estimated bone strength were associated with lower risk of MACE after adjustment for relevant confounders. © 2021 American Society for Bone and Mineral Research (ASBMR).

Sex Differences in the Association Between Bone Mineral Density and Coronary Artery Disease in Patients Referred for Cardiac Computed Tomography

Atherosclerosis and osteoporosis are both common and preventable diseases. Evidence supports a link between coronary artery disease (CAD) and low bone mineral density (BMD). This study aimed to assess the association between thoracic spine BMD and CAD in men and women with symptoms suggestive of CAD. This cross-sectional study included 1487 (mean age 57 years (range 40-80), 47% men) patients referred for cardiac computed tomography (CT). Agatston coronary artery calcium score (CACS), CAD severity (no, mild, moderate, and severe), vessel involvement (no, 1-, 2-, and 3/left main disease), and invasive measurements were evaluated. BMD of three thoracic vertebrae was measured using quantitative CT. We used the American college of radiology cut-off values for lumbar spine BMD to categorize patients into very low (<80 mg/cm³), low (80-120 mg/cm³), or normal BMD (>120 mg/cm³). BMD as a continuous variable was included in the linear regression analyses to assess associations between CACS (CACS=0, CACS 1- 399, and CACS ≥ 400) and BMD, and CAD severity and BMD. Significant lower BMD was present with increasing CACS and stenosis degree unadjusted. Multivariate linear regression analyses in women revealed a significant correlation between BMD and CACS groups (β = -4.06, p<0.05), but no correlation between BMD and CAD severity (β = -1.59, p = 0.14). No association was found between BMD and CACS (β = -1.50, p = 0.36) and CAD severity (β = 0.07, p = 0.94) in men. BMD is significantly correlated to CACS after adjusting for confounders in women, but not in men, suggesting a possible sex difference in pathophysiology.

Cross-sectional association of bone mineral density with coronary artery calcification in an international multi-ethnic population-based cohort of men aged 40-49: ERA JUMP study

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Significant association of atherosclerosis and bone mineral density has been reported.

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The association has been reported in postmenopausal women and elderly men.

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This study reported the association in an international cohort of middle-aged men.

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Coronary artery calcification was used as a biomarker of coronary atherosclerosis.

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Vertebral bone density was used as a surrogate marker of bone mineral density.

Introduction

Inverse associations of cardiovascular disease (CVD) and atherosclerosis with osteoporosis and bone mineral density (BMD) have been reported in post-menopausal women and elderly men. We aimed to investigate an association between vetebral bone density (VBD) and coronary artery cacification (CAC) in an international multi-ethnic cohort of middle-aged men in the EBCT and Risk Factor Assessment among Japanese and US Men in the Post-World-War-II birth cohort (ERA JUMP).

Methods

ERA JUMP examined 1134 men aged 40–49 (267 white, 84 black, and 242 Japanese Americans, 308 Japanese in Japan, and 233 Koreans in South Korea) free from CVD for CAC, and VBD, biomarkers of coronary atherosclerosis and BMD, respectively, with electron-beam computed tomography, and other risk factors. CAC was quantified with the Agatston method and VBD by computing the mean Hounsfield Unit (HU) value of the T12 to L3 vertebrae. To examine multivariable-adjusted associations of CAC with VBD, we used robust linear and logistic regressions.

Results

The mean VBD and median CAC were 175.4 HU (standard deviation: 36.3) and 0 (interquartile range: (0, 4.5)), respectively. The frequency of CAC was 19.0%. There was no significant interaction by race. VBD had a significant inverse association with CAC score (β = −0.207, p-value = 0.005), while a 10-unit increase in VBD was significantly associated with the frequency of CAC (odds ratio (95% confidence interval) = 0.929 (0.890–0.969)). Both associations remained significant after adjusting for covariates.

Conclusions

VBD had a significant inverse association with CAC in this international multi-ethnic cohort of men aged 40–49.

Calcification of Cardiac Valves in Metabolic Bone Disease: An Updated Review of Clinical Studies

Epidemiological and clinical data have suggested the existence of a relationship between cardiovascular diseases and metabolic bone disease. Several studies have demonstrated that heart valve calcification presents substantial similarities with that of bone. Literature data indicate that there are many active processes which promote osteogenesis and loss of mineralization inhibitors that lead to the deposition of extracellular matrix and proteins of bone tissue in cardiac valves. This review aimed to synthesize the available data in order to allow a better understanding of the relationship between osteoporosis or other metabolic bone diseases, such as primary hyperparathyroidism, and valvular calcification in humans. Electronic databases of Pubmed-Medline, Cochrane Library, and SCOPUS from inception to March 31, 2019 were searched. The full set of the articles potentially eligible were carefully assessed and reviewed. Finally, 23 studies were eligible and included in the systematic review. The majority of studies reported that osteoporosis and/or osteopenia were independent risk factors for valvular calcifications, even after adjusting for common cardiovascular risk factors. This suggests that this relationship is not only due to the presence of common cardiovascular risk factors but rather to underlying biological factors that connect them. Instead, regarding the association between primary hyperparathyroidism and valve calcification, conflicting data were found in the literature. To sum up, most of the literature data confirm that cardiac valve calcification processes are strongly influenced by alterations in bone metabolism. In particular, the patients with osteoporosis or primary hyperparathyroidism have an acceleration in the process of valvular calcification. Additional studies are needed to specifically address the mechanisms by which metabolic bone diseases could influence cardiac valve calcification.

Relationship of volumetric bone mineral density by quantitative computed tomography with abdominal aortic calcification

OBJECTIVE

This multicenter study aimed to evaluate the association between volumetric bone mineral density (vBMD) and abdominal aortic calcification (AAC) in a Chinese population.

METHODS

Quantitative computed tomography (QCT) and Agatston score (AS) were used to measure vBMD and AAC, respectively, in 3457 participants during 2013-2017. The association between vBMD and AAC was assessed using multivariate regression analysis, adjusted for age, residence, education, body mass index, and other cardiovascular risk factors.

RESULTS

The mean age of women and men was 61.4 and 62.7 years, respectively. In total, 30.4% of women and 37.7% of men were found to have AAC. After full adjustment, higher vBMD was associated with lower AAC score (β, -0.095; 95% confidence interval [CI], -0.167 to -0.024; P = 0.0087) and lower AAC prevalence (odds ratio [OR], 0.873; 95% CI, 0.824 to 0.924; P < 0.0001) in men. Inverse trends were also observed in the association of vBMD quartile with AAC severity (lowest vs highest quartile; β = 0.235; 95% CI, 0.011 to 0.459; P_trend < 0.0001) and AAC prevalence (lowest vs highest quartile; OR = 1.329; 95% CI, 1.087 to 1.625; P_trend < 0.0001) in men. However, no significant result was obtained in women, except for the association between quartiles of vBMD and AAC score.

CONCLUSIONS

In our study, vBMD was inversely associated with AAC among men independent of age and shared risk factors. However, the association was not significant among women.

Biomarkers of aortic bioprosthetic valve structural degeneration

PURPOSE OF REVIEW

Bioprosthetic valves are now used for the majority of surgical aortic valve replacements and for all transcatheter aortic valve replacements. However, bioprostheses are subject to structural valve deterioration (SVD) and have, therefore limited durability.

RECENT FINDINGS

Clinical, imaging, and circulating biomarkers may help to predict or indicate the presence of bioprosthetic valve SVD. The most important biomarkers of SVD includes: patient-related clinical biomarkers, such as diabetes and renal failure; valve-related biomarkers, such as absence of antimineralization process and severe prosthesis-patient mismatch; imaging biomarkers: the presence of valve leaflet mineralization on multidetector computed tomography or sodium fluoride uptake on positron emission tomography; and circulating biomarkers including: increased levels of HOMA index, ApoB/ApoA-I ratio, PCSK9, Lp-PLA2, phosphocalcic product. The assessment of these biomarkers may help to enhance risk stratification for SVD following AVR and may contribute to open novel pharmacotherapeutic avenues for the prevention of SVD.

SUMMARY

SVD may affect all bioprostheses after aortic valve replacement, and is the main cause of bioprosthetic valve failure and reintervention during the follow-up. Comprehensive assessment of clinical, imaging, and circulating biomarkers associated with earlier SVD could help strengthen the follow-up in high-risk patients and provide novel pharmacologic therapeutic strategies.

No Association Between Bone Mineral Density and Breast Arterial Calcification Among Postmenopausal Women

Context

The association between bone mineral density (BMD) and breast arterial calcification (BAC) remains poorly understood and controversial.

Objective

The objective of this article is to examine the association between BMD and BAC in a large cohort of postmenopausal women undergoing routine mammography.

Design

A cross-sectional analysis of baseline data from a multiethnic cohort was performed.

Setting

The setting for this analysis is an integrated health care delivery system in Northern California in the United States.

Patients

A total of 1273 women age 60 to 79 years (mean age, 67 years) were recruited within 12 months of screening mammography.

Main outcome measure

A BAC score (mg) was obtained from digital mammograms using a novel densitometry method. BAC presence was defined as a BAC score greater than 0 mg, and severe BAC as a BAC score greater than 20 mg.

Results

Overall, 53% of women had osteopenia and 21% had osteoporosis. The prevalence of BAC greater than 0 mg was 29%, 30%, and 29% among women with normal BMD, osteopenia, and osteoporosis, respectively (P = 0.98). The prevalence of BAC greater than 20 mg was 5%, 3%, and 5% among women with normal BMD, osteopenia and osteoporosis, respectively (P = .65). The odds ratios (ORs) of BAC greater than 0 mg vs BAC = 0 mg after multivariable adjustment were 1.09 (95% CI, 0.81-1.48; P = .54) for osteopenia and 0.99 (95% CI, 0.69-1.48; P = .98) for osteoporosis. The adjusted ORs for BAC greater than 20 mg vs BAC 20 mg or less were 1.03 (95% CI, 0.52-2.01; P = .93) for osteopenia and 1.89 (95 CI, 0.81-4.47; P = .14) for osteoporosis.

Conclusion

Our findings do not support an association of either osteopenia or osteoporosis with BAC presence or severity among postmenopausal women.

Increased Serum Parathyroid Hormone, Osteocalcin and Alkaline Phosphatase Are Associated with a Long-Term Adverse Cardiovascular Outcome after Coronary Artery Bypass Graft Surgery

Despite the fact that an association of osteopoenia/osteoporosis with elevated risk of coronary artery calcification (CAC) and coronary atherosclerosis (CA) is well-established, it remains unclear whether bone turnover markers can be employed in long-term prognostication of such patients. Here we measured serum calcium, phosphate, calcitonin, parathyroid hormone (PTH), osteoprotegerin, osteocalcin, osteopontin, alkaline phosphatase and its bone isoenzyme, subsequently correlating them with an adverse cardiovascular outcome after 3 years of follow-up. The extent of brachiocephalic artery stenosis, CA, or CAC, as well as prevalence of osteopoenia/osteoporosis before the coronary artery bypass graft (CABG) surgery, did not differ between outcome groups, suggesting that subtle molecular mechanisms might be involved in determining the outcome rather than clinical or subclinical disease. After stepwise logistic regression, serum osteocalcin > 26.8 ng/mL and PTH > 49.1 pg/mL were independent predictors of an adverse outcome. Serum ionised calcium correlated with multivessel coronary artery disease; moreover, patients with severe CA (SYNTAX score > 21) had higher serum ionised calcium than those with mild CA. Likewise, serum alkaline phosphatase was associated with severe CA and CAC (Agatston score > 400). In conclusion, serum PTH, osteocalcin, and alkaline phosphatase are associated with an adverse cardiovascular outcome 3 years after CABG surgery regardless of osteopoenia/osteoporosis, coronary/peripheral atherosclerosis, and CAC.

[Dynamics of Coronary Calcification and Its Association with the Clinical Course of Ischemic Heart Disease and Osteopenic Syndrome]

PURPOSE

to study the relationship between degree of calcification of coronary arteries, osteopenic syndrome, and clinical course of ischemic heart disease (IHD) during 3-5 years of follow-up in men after coronary artery bypass grafting (CABG). Materials and methods. We included in this prospective study 111 men admitted for CABG under cardiopulmonary bypass. All patients underwent color duplex scanning (CDS) of brachiocephalic arteries (BCA), coronary angiography, multislice computed tomography (MSCT) of coronary arteries (CAs) to assess the degree of calcification, densitometry of femoral neck. Cardiac calcium score of the vessels was assessed by the Agatston method. After 3-5 (mean 4.2) years we assessed dead or alive status of 111 patients. Mortality during followup was 11.7 % (n=13). In 59 of 98 survived patients we repeated CDS of BCA and MSCT of CAs with calculation of CA calcification scores.

RESULTS

Significant CA calcification prior to CABG was detected in more than half of the patients (57.6 %). Among all clinical and anamnestic factors only one risk factor - smoking was associated with mortality (odds ratio [OR] 9.8, 95 % confidence interval [CI] 1.2-78.1, χ2=6.6, р=0.01). There were no association of mortality with index of CA calcification, Syntax score, osteopenic syndrome and BCA involvement. In the group of patients with baseline coronary calcification index &gt;400 there were more smokers (р=0.026) and patients with lesions in &gt;3 CAs (р=0.037) compared with the group with values ≤400. At the preoperative stage we revealed associations of CAs calcification index with T-test characterizing presence of the osteopenic syndrome (r= -0.24, р=0.06), Syntax score (r=0.26, р=0.041), and number of affected CAs (r=0.25, р=0.048). At repeated examination 3-5 years after CABG a medium positive correlation was detected between the severity of CA calcification and the severity of BCA stenoses (r=0.28, р=0.029). Linear regression analysis with stepwise selection identified baseline (prior to CABG) higher values of T-test evaluated at femoral bone as the only significant predictor of calcium score increase during 3-5 years of follow-up.

CONCLUSION

Dynamics of calcification of CAs in men with IHD during 3-5 years of follow-up after CABG was multidirectional, but in most cases (66 %) it was progressive. There was correlation between coronary calcification and smoking status and decreased T-test assessed at femoral bone prior to CABG. In the long-term follow-up period the correlation between severity of BCA lesion and severity of coronary  calcification was found. Negative correlation was detected between progression of coronary calcification and baseline impairment of mineral density of femoral bone.

The relationship between volumetric thoracic bone mineral density and coronary calcification in men and women - results from the Copenhagen General Population Study

BACKGROUND

The association between low bone mineral density (BMD) and the presence of coronary artery calcium (CAC) as a marker of atherosclerosis is unclear. The aim of this study was to assess the potential relationship between volumetric thoracic bone mineral density and coronary calcification in a large population of men and women.

METHODS

Participants from the Copenhagen General Population Study underwent multidetector computed tomography. Volumetric thoracic BMD and CAC were assessed in the same scan. CAC was measured using calibrated mass score (cMS). cMS was dichotomized as cMS = 0 or cMS > 0. The association between BMD and cMS was analyzed using multiple logistic regression in men, premenopausal and postmenopausal women. The model was adjusted for age, BMI, hypertension, hypercholesterolemia, diabetes, known cardiovascular disease and smoking.

RESULTS

Of 2548 eligible participants, 1163 men and 1385 women, mean age 61 ± 10 were included in the study. Mean BMD was 138 ± 46 mg/cm³ for men and 151 ± 49 mg/cm³ women. In 696 men (67%) and 537 women (41%) cMS was found to be above zero. For men, a decrease in BMD of 100 mg/cm³ was associated to an odds ratio of 1.49 for cMS > 0 (95% confidence interval: 1.04-2.13, P = 0.03). In postmenopausal women, a decrease in BMD of 100 mg/cm³ was associated to an odds ratio of 1.47 for MS > 0 (95% confidence interval: 1.04-2.08, P = 0.03). For premenopausal women, no significant association was found between BMD and cMS (odds ratio = 0.74, 95% confidence interval: 0.36-1.52, P = 0.4).

CONCLUSION

Bone mineral density and coronary calcification are inversely related in both men and postmenopausal women, supporting the hypothesis that a direct relation between bone loss and development of atherosclerosis exists irrespective of gender.

Prediction of incident vertebral fracture using CT-based finite element analysis

Prior studies show vertebral strength from computed tomography-based finite element analysis may be associated with vertebral fracture risk. We found vertebral strength had a strong association with new vertebral fractures, suggesting that vertebral strength measures identify those at risk for vertebral fracture and may be a useful clinical tool.

INTRODUCTION

We aimed to determine the association between vertebral strength by quantitative computed tomography (CT)-based finite element analysis (FEA) and incident vertebral fracture (VF). In addition, we examined sensitivity and specificity of previously proposed diagnostic thresholds for fragile bone strength and low BMD in predicting VF.

METHODS

In a case-control study, 26 incident VF cases (13 men, 13 women) and 62 age- and sex-matched controls aged 50 to 85 years were selected from the Framingham multi-detector computed tomography cohort. Vertebral compressive strength, integral vBMD, trabecular vBMD, CT-based BMC, and CT-based aBMD were measured from CT scans of the lumbar spine.

RESULTS

Lower vertebral strength at baseline was associated with an increased risk of new or worsening VF after adjusting for age, BMI, and prevalent VF status (odds ratio (OR) = 5.2 per 1 SD decrease, 95% CI 1.3-19.8). Area under receiver operating characteristic (ROC) curve comparisons revealed that vertebral strength better predicted incident VF than CT-based aBMD (AUC = 0.804 vs. 0.715, p = 0.05) but was not better than integral vBMD (AUC = 0.815) or CT-based BMC (AUC = 0.794). Additionally, proposed fragile bone strength thresholds trended toward better sensitivity for identifying VF than that of aBMD-classified osteoporosis (0.46 vs. 0.23, p = 0.09).

CONCLUSION

This study shows an association between vertebral strength measures and incident vertebral fracture in men and women. Though limited by a small sample size, our findings also suggest that bone strength estimates by CT-based FEA provide equivalent or better ability to predict incident vertebral fracture compared to CT-based aBMD. Our study confirms that CT-based estimates of vertebral strength from FEA are useful for identifying patients who are at high risk for vertebral fracture.

Bone Mineral Density of the Radius Predicts All-Cause Mortality in Patients With Type 2 Diabetes: Diabetes Heart Study

This study aimed to determine the association between areal and volumetric bone mineral density (BMD) with all-cause mortality in patients with type 2 diabetes (T2D). Associations between BMD and all-cause mortality were examined in 576 women and 517 men with T2D in the Diabetes Heart Study. Volumetric BMD in the thoracic and lumbar spine was measured with quantitative computed tomography. Areal BMD (aBMD) in the lumbar spine, total hip, femoral neck, ultradistal radius, mid radius, and whole body was measured using dual X-ray absorptiometry. Association of BMD with all-cause mortality was determined using sequential models, stratified by sex: (1) unadjusted; (2) adjusted for age, race, smoking, alcohol, estrogen use; (3) model 2 plus history of cardiovascular disease, hypertension, and coronary artery calcification; (4) model 3 plus lean mass; and (5) model 3 plus fat mass. At baseline, mean age was 61.2 years for women and 62.7 years for men. At mean 11.0 ± 3.7 years' follow-up, 221 (36.4%) women and 238 (43.6%) men were deceased. In women, BMD at all skeletal sites (except spine aBMD and whole body aBMD) was inversely associated with all-cause mortality in the unadjusted model. These associations remained significant in the mid radius (hazard ratio per standard deviation  = 0.79; p = 0.0057) and distal radius (hazard ratio per standard deviation  = 0.76; p = 0.0056) after adjusting for all covariates, including lean mass. In men, volumetric BMD measurements but not aBMD were inversely associated with mortality and only in the unadjusted model. In this longitudinal study, lower baseline aBMD in the radius was associated with increased all-cause mortality in women with T2D, but not men, independent of other risk factors for death.

Abdominal aortic calcification and the risk of bone fractures: a meta-analysis of prospective cohort studies

The relationship between abdominal aortic calcification (AAC) and bone fracture has been examined by some observational studies, but the results remain discordant. Therefore, we aimed to assess the link between them by conducting a meta-analysis of prospective studies. Relevant studies were identified by searching PubMed and EMBASE databases until the end of December 2016. Summary relative risks (RRs) and 95% confidence intervals (CIs) for associations between AAC and fracture risk were estimated with fixed- or random- effects models. Seven prospective studies were included in the final analysis. The summarized RRs of any type of fractures for the highest compared with the lowest category of AAC were 1.64 (95% CI 1.30-2.07, P = 0.000) with mild heterogeneity (I ² = 30.1%, P = 0.188). Subgroup analysis showed that the association between AAC and fracture was not significantly modified by gender and follow-up length. Risks were similar when analyses were restricted to the studies with adjustment for bone mineral density (BMD) (RR = 1.76, 95% CI 1.31-2.38, P = 0.000, I ² = 49.1%). For the specific type of fracture, severe AAC was significantly related with hip fracture (RR = 1.64, 95% CI 1.22-2.20, P = 0.001, n = 5), but not with vertebral (RR = 1.45, 95% CI 0.81-2.58, P = 0.213, n = 3) or non-vertebral fracture (RR = 1.35, 95% CI 0.96-1.88, P = 0.081, n = 3). There was no evidence of publication bias. Our findings demonstrated that AAC was significantly and independently associated with a higher fracture risk, especially for hip fracture.

Diabetes and Abdominal Aortic Calcification-a Systematic Review

PURPOSE OF REVIEW

A systematic literature review was performed to evaluate diabetes mellitus (DM) as a risk factor of abdominal aortic calcification (AAC), and address factors that might contribute to the development of AAC in DM patients.

RECENT FINDINGS

DM is an independent risk factor of AAC development. Bone metabolism along with lifestyle factors among DM patients makes them more prone to AAC. Hip and vertebral fractures, high phosphate, smoking, hypertension, and low osteocalcin could make DM patients prone to AAC. Low levels of high-density lipoprotein (HDL), high low-density lipoprotein (LDL), high total cholesterol/HDL ratio, low bone mineral density (BMD) may be risk factors, but the literature is more ambiguous. Body mass index (BMI) does not appear to increase risk of AAC. High phosphate levels and low osteocalcin levels seem to be biomarkers of AAC in patients with diabetes. However, the association between DM and AAC is complicated.

Diabetes and Deficits in Cortical Bone Density, Microarchitecture, and Bone Size: Framingham HR-pQCT Study

Older adults with type 2 diabetes (T2D) tend to have normal or greater areal bone mineral density (aBMD), as measured by DXA, than those who do not have diabetes (non-T2D). Yet risk of fracture is higher in T2D, including 40% to 50% increased hip fracture risk. We used HR-pQCT to investigate structural mechanisms underlying skeletal fragility in T2D. We compared cortical and trabecular bone microarchitecture, density, bone area, and strength in T2D and non-T2D. In secondary analyses we evaluated whether associations between T2D and bone measures differed according to prior fracture, sex, and obesity. Participants included 1069 members of the Framingham Study, who attended examinations in 2005 to 2008 and underwent HR-pQCT scanning in 2012 to 2015. Mean age was 64 ± 8 years (range, 40 to 87 years), and 12% (n = 129) had T2D. After adjustment for age, sex, weight, and height, T2D had lower cortical volumetric BMD (vBMD) (p < 0.01), higher cortical porosity (p = 0.02), and smaller cross-sectional area (p = 0.04) at the tibia, but not radius. Trabecular indices were similar or more favorable in T2D than non-T2D. Associations between T2D and bone measures did not differ according to sex or obesity status (all interaction p > 0.05); however, associations did differ in those with a prior fracture and those with no history of fracture. Specifically, cortical vBMD at the tibia and cortical thickness at the radius were lower in T2D than non-T2D, but only among those individuals with a prior fracture. Cortical porosity at the radius was higher in T2D than non-T2D, but only among those who did not have a prior fracture. Findings from this large, community-based study of older adults suggest that modest deterioration in cortical bone and reductions in bone area may characterize diabetic bone disease in older adults. Evaluation of these deficits as predictors of fracture in T2D is needed to develop prevention strategies in this rapidly increasing population of older adults. © 2017 American Society for Bone and Mineral Research.

Relationship of bone mineral density with valvular and annular calcification in community-dwelling older people: The Cardiovascular Health Study

Associations between bone mineral density and aortic valvular, aortic annular, and mitral annular calcification were investigated in a cross-sectional analysis of a population-based cohort of 1497 older adults. Although there was no association between continuous bone mineral density and outcomes, a significant association between osteoporosis and aortic valvular calcification in men was found.

INTRODUCTION

The process of cardiac calcification bears a resemblance to skeletal bone metabolism and its regulation. Experimental studies suggest that bone mineral density (BMD) and valvular calcification may be reciprocally related, but epidemiologic data are sparse.

METHODS

We tested the hypothesis that BMD of the total hip and femoral neck measured by dual-energy X-ray absorptiometry (DXA) is inversely associated with prevalence of three echocardiographic measures of cardiac calcification in a cross-sectional analysis of 1497 older adults from the Cardiovascular Health Study. The adjusted association of BMD with aortic valve calcification (AVC), aortic annular calcification (AAC), and mitral annular calcification (MAC) was assessed with relative risk (RR) regression.

RESULTS

Mean (SD) age was 76.2 (4.8) years; 58% were women. Cardiac calcification was highly prevalent in women and men: AVC, 59.5 and 71.0%; AAC 45.1 and 46.7%; MAC 42.8 and 39.5%, respectively. After limited and full adjustment for potential confounders, no statistically significant associations were detected between continuous BMD at either site and the three measures of calcification. Assessment of WHO BMD categories revealed a significant association between osteoporosis at the total hip and AVC in men (adjusted RR compared with normal BMD = 1.24 (1.01-1.53)). In graded sensitivity analyses, there were apparent inverse associations between femoral neck BMD and AVC with stenosis in men, and femoral neck BMD and moderate/severe MAC in women, but these were not significant.

CONCLUSION

These findings support further investigation of the sex-specific relationships between low BMD and cardiac calcification, and whether processes linking the two could be targeted for therapeutic ends.

Cardiovascular calcification and subcortical bone demineralization in hypertension

The present study investigated cardiovascular calcification, peripheral bone mineral density (BMD), and lab indices in hypertensive patients aged 55-74 years without severe kidney dysfunction. Cardiovascular calcification was investigated by ultrasound examinations at eight sites: aortic valve, left and right common carotid artery, left and right carotid artery bifurcation, left and right internal carotid artery, and abdominal aorta. The presence/absence of calcification at each site was coded as 1/0, respectively, for the calculation of a cumulative score. Peripheral bone mineral density was assessed by forearm quantitative computed tomography (pQCT) and was defined as low if the T-score was <-1. Lab work-up included plasma creatinine, calcium, phosphorus, parathyroid hormone and 25-(OH) vitamin D measurements. Ninety-one patients were studied. The range was 2-8 for the calcification score and 229-492 mg cm^-3 for bone mineral density. The prevalence of low bone densitometry was 83.5%. The calcification score and bone densitometry were inversely correlated in a non-adjusted analysis (R=-0.297, P=0.004) and in multivariable regression (beta=-0.335, P=0.003). The association was significant for subcortical bone (beta=-0.302, P=0.007) but not for cortical bone or trabecular bone (P⩾0.194 in both cases). The calcification score was associated with a low prevalence of bone densitometry in the non-adjusted analysis (odds ratio=2.53, 95% CI=1.41/4.54, P=0.002) and in the multivariable logistic regression (odds ratio=2.46, 95% CI=1.25/4.81, P=0.009). Cardiovascular calcification was independently associated with peripheral bone densitometry in hypertensive patients. The data support the hypothesis that vascular calcification and low bone densitometry share some determinants in hypertensive patients.

Lower leg arterial calcification assessed by high-resolution peripheral quantitative computed tomography is associated with bone microstructure abnormalities in women

In older women, the presence of lower leg arterial calcification assessed by high-resolution peripheral quantitative computed tomography is associated with relevant bone microstructure abnormalities at the distal tibia and distal radius.

INTRODUCTION

Here, we report the relationships of bone geometry, volumetric bone mineral density (BMD) and bone microarchitecture with lower leg arterial calcification (LLAC) as assessed by high-resolution peripheral quantitative computed tomography (HR-pQCT).

METHODS

We utilized the Hertfordshire Cohort Study (HCS), where we were able to study associations between measures obtained from HR-pQCT of the distal radius and distal tibia in 341 participants with or without LLAC. Statistical analyses were performed separately for women and men. We used linear regression models to investigate the cross-sectional relationships between LLAC and bone parameters.

RESULTS

The mean (SD) age of participants was 76.4 (2.6) and 76.1 (2.5) years in women and men, respectively. One hundred and eleven of 341 participants (32.6 %) had LLAC that were visible and quantifiable by HR-pQCT. The prevalence of LLAC was higher in men than in women (46.4 % (n = 83) vs. 17.3 % (n = 28), p < 0.001). After adjustment for confounding factors, we found that women with LLAC had substantially lower Ct.area (β = -0.33, p = 0.016), lower Tb.N (β = -0.54, p = 0.013) and higher Tb.Sp (β = 0.54, p = 0.012) at the distal tibia and lower Tb.Th (β = -0.49, p = 0.027) at the distal radius compared with participants without LLAC. Distal radial or tibial bone parameter analyses in men according to their LLAC status revealed no significant differences with the exception of Tb.N (β = 0.27, p = 0.035) at the distal tibia.

CONCLUSION

In the HCS, the presence of LLAC assessed by HR-pQCT was associated with relevant bone microstructure abnormalities in women. These findings need to be replicated and further research should study possible pathophysiological links between vascular calcification and osteoporosis.

Bone Mineral Density and Progression of Subclinical Atherosclerosis in African-Americans With Type 2 Diabetes

CONTEXT

Relative to European Americans, calcified atherosclerotic plaque (CP) is less prevalent and severe in African-Americans (AAs).

OBJECTIVE

Predictors of progression of CP in the aorta, carotid, and coronary arteries were examined in AAs over a mean 5.3 ± 1.4-year interval.

DESIGN

This is the African American-Diabetes Heart Study.

SETTING

A type 2 diabetes (T2D)-affected cohort was included.

PARTICIPANTS

A total of 300 unrelated AAs with T2D; 50% female, mean age 55 ± 9 years, baseline hemoglobin A1c 8.1 ± 1.8% was included.

MAIN OUTCOME MEASURES

Glycemic control, renal parameters, vitamin D, and computed tomography-derived measures of adiposity, vascular CP, and volumetric bone mineral density (vBMD) in lumbar and thoracic vertebrae were obtained at baseline and follow-up.

RESULTS

CP increased in incidence and quantity/mass in all three vascular beds over the 5-year study (P < .0001). Lower baseline lumbar and thoracic vBMD were associated with progression of abdominal aorta CP (P < .008), but not progression of carotid or coronary artery CP. Lower baseline estimated glomerular filtration rate was associated with progression of carotid artery CP (P = .0004), and higher baseline pericardial adipose volume was associated with progression of coronary artery (P = .001) and aorta (P = .0006) CP independent of body mass index. There was a trend for an inverse relationship between change in thoracic vBMD and change in aortic CP (P = .05).

CONCLUSIONS

In this longitudinal study, lower baseline thoracic and lumbar vBMD and estimated glomerular filtration rate and higher pericardial adipose volumes were associated with increases in CP in AAs with T2D. Changes in these variables and baseline levels and/or changes in glycemic control, albuminuria, and vitamin D were not significantly associated with progression of CP.

Osteoporosis, osteoporotic fractures, and carotid artery calcification detected on panoramic radiographs in Japanese men and women

OBJECTIVES

We investigated the association among diagnosed osteoporosis, osteoporotic fractures, and carotid artery calcification (CAC) detected on panoramic radiographs. Additionally, we assessed whether osteoporosis or fractures could be predicted by an incidental finding of CAC.

STUDY DESIGN

One thousand twenty-one patients participated in this study. Patients completed a structured questionnaire. Logistic regression analysis adjusted for covariates was used to calculate the odds ratio (95% confidence interval) for diagnosed osteoporosis or fractures according to the presence of CAC. Extended receiver operating characteristic (ROC) curve analysis was used to clarify whether osteoporosis or fractures were predicted by the detection of CAC.

RESULTS

The odds ratios for diagnosed osteoporosis or fracture associated with CAC were 1.82 (1.02-3.24) and 0.77 (0.33-1.77), respectively. The areas under the ROC curves for identifying patients with osteoporosis or fractures according to the detection of CAC were 0.54 and 0.50, respectively.

CONCLUSIONS

CAC may not be useful for identifying Japanese individuals with osteoporosis or those at risk of fracture, although the presence of CAC was significantly associated with a history of diagnosed osteoporosis without osteoporotic fractures.

Osteoporosis and vascular calcification in postmenopausal women: a cross-sectional study

Objectives To estimate the correlation between osteoporosis and vascular calcification in postmenopausal women and the influence of calcium/vitamin D supplements on vascular calcification. Methods A cross-sectional study was performed including 29 women with osteoporosis (15 not taking supplements) and 18 age-matched, non-osteoporotic women. They were evaluated for cardiovascular risk factors and blood tests, lateral X-ray of lumbar spine (assessment of abdominal aorta calcification, AAC) and carotid ultrasound (increased intima media thickness (iIMT) or calcified plaques) were performed. Results In univariate analysis, osteoporotic women were 16 times more likely to develop AAC (odds ratio (OR) 15.8, 95% confidence interval (CI) 1.9-135.4) and seven times more likely to develop iIMT (OR 6.8, 95% CI 1.8-25.4) compared to normal individuals. The odds of developing AAC and iIMT were increased each year after menopause (OR 1.11, 95% CI 1.01-1.2 and OR 1.18, 95% CI 1.05-1.3, respectively) and with aging (OR 1.27, 95% CI 1.1-1.47 and OR = 1.17, 95% CI 1.04-1.3, respectively). Calcified plaques were significantly correlated with osteoporosis (p = 0.014). In multivariate analysis, osteoporosis was an independent risk factor for AAC (OR 13.3, 95% CI 1.3-134.4) and iIMT (OR 4.7, 95% CI 1.1-19.9). Low doses of supplements did not appear to affect vascular calcification (p = 0.6). Conclusions Osteoporosis is associated with increased calcification of the abdominal aorta and carotids. Low doses of supplements do not appear to cause any increase in vascular calcification in osteoporotic women.

Abdominal aortic calcification: A reappraisal of epidemiological and pathophysiological data

In men and women, there is a significant association between the risk of cardiovascular event (myocardial infarction, stroke) and risk of major fragility fracture (hip, vertebra). Abdominal aortic calcification (AAC) can be assessed using semiquantitative scores on spine radiographs and spine scans obtained by DXA. Severe AAC is associated with higher risk of major cardiovascular event. Not only does severe AAC reflect poor cardiovascular health status, but also directly disturbs blood flow in the vascular system. Severe (but not mild or moderate) AAC is associated with lower bone mineral density (BMD), faster bone loss and higher risk of major fragility fracture. The fracture risk remains increased after adjustment for BMD and other potential risk factors. The association between severe AAC and fracture risk was found in both sexes, mainly in the follow-ups of less than 10years. Many factors contribute to initiation and progression of AAC: lifestyle, co-morbidities, inorganic ions, dyslipidemia, hormones, cytokines (e.g. inflammatory cytokines, RANKL), matrix vesicles, microRNAs, structural proteins (e.g. elastin), vitamin K-dependent proteins, and medications (e.g. vitamin K antagonists). Osteogenic transdifferentiation of vascular smooth muscle cells (VSMC) and circulating osteoprogenitors penetrating into vascular wall plays a major role in the AAC initiation and progression. Vitamin K-dependent proteins protect vascular tunica media against formation of calcified deposits (matrix GLA protein, GLA-rich protein) and against VSMC apoptosis (Gas6). Further studies are needed to investigate clinical utility of AAC for the assessment of fracture and cardiovascular risk at the individual level and develop new medications permitting to prevent AAC progression.

Abdominal aortic calcification and risk of fracture among older women - The SOF study

Data concerning the link between severity of abdominal aortic calcification (AAC) and fracture risk in postmenopausal women are discordant. This association may vary by skeletal site and duration of follow-up. Our aim was to assess the association between the AAC severity and fracture risk in older women over the short- and long term. This is a case-cohort study nested in a large multicenter prospective cohort study. The association between AAC and fracture was assessed using Odds Ratios (OR) and 95% confidence intervals (95%CI) for vertebral fractures and using Hazard Risks (HR) and 95%CI for non-vertebral and hip fractures. AAC severity was evaluated from lateral spine radiographs using Kauppila's semiquantitative score. Severe AAC (AAC score 5+) was associated with higher risk of vertebral fracture during 4 years of follow-up, after adjustment for confounders (age, BMI, walking, smoking, hip bone mineral density, prevalent vertebral fracture, systolic blood pressure, hormone replacement therapy) (OR=2.31, 95%CI: 1.24-4.30, p<0.01). In a similar model, severe AAC was associated with an increase in the hip fracture risk (HR=2.88, 95%CI: 1.00-8.36, p=0.05). AAC was not associated with the risk of any non-vertebral fracture. AAC was not associated with the fracture risk after 15 years of follow-up. In elderly women, severe AAC is associated with higher short-term risk of vertebral and hip fractures, but not with the long-term risk of these fractures. There is no association between AAC and risk of non-vertebral-non-hip fracture in older women. Our findings lend further support to the hypothesis that AAC and skeletal fragility are related.

Secreted klotho protein attenuates osteogenic differentiation of human bone marrow mesenchymal stem cells in vitro via inactivation of the FGFR1/ERK signaling pathway

Increasing evidence indicates that the osteogenic differentiation of mesenchymal stem cells (MSCs) is related to bone formation, heterotopic ossification, and even vascular calcification. Therefore, it is essential to understand the microenvironment that regulates these processes. The Klotho gene plays an important role in tissue mineralization, and its secreted protein functions as a hormone. We investigated the effects of secreted Klotho protein on the osteogenesis of human bone marrow MSC (hBMSCs). To this end, the cells received osteogenic medium with or without Klotho protein. The results showed that osteoblast-specific gene expression and mineral deposition were decreased when MSCs were incubated with Klotho. Klotho reduced the expression of fibroblast growth factor receptor 1 (FGFR1) and phosphorylated extracellular signal-regulated kinase 1/2. However, both MEK and FGFR1 inhibitors delayed bone mineral formation more than Klotho. These data suggest that secreted Klotho protein attenuates the osteogenic differentiation of hBMSCs in vitro through FGFR1/ERK signaling.