Relationship between serum hsCRP concentration and biochemical bone turnover markers in healthy pre- and postmenopausal women

Prune Consumption Attenuates Proinflammatory Cytokine Secretion and Alters Monocyte Activation in Postmenopausal Women: Secondary Outcome Analysis of a 12-Mo Randomized Controlled Trial: The Prune Study

BACKGROUND

Proinflammatory cytokines are implicated in the pathophysiology of postmenopausal bone loss. Clinical studies demonstrate that prunes prevent bone mineral density loss; however, the mechanism underlying this effect is unknown.

OBJECTIVE

We investigated the effect of prune supplementation on immune, inflammatory, and oxidative stress markers.

METHODS

A secondary analysis was conducted in the Prune Study, a single-center, parallel-arm, 12-mo randomized controlled trial of postmenopausal women (55-75 y old; n = 235 recruited; n = 183 completed) who were assigned to 1 of 3 groups: "no-prune" control, 50 g prune/d and 100 g prune/d groups. At baseline and after 12 mo of intervention, blood samples were collected to measure serum high-sensitivity C-reactive protein (hs-CRP), serum total antioxidant capacity (TAC), plasma 8-isoprostane, proinflammatory cytokines [interleukin (IL)-1β, IL-6, IL-8, monocyte chemoattractant protein-1, and tumor necrosis factor (TNF)-α] concentrations in plasma and lipopolysaccharide (LPS)-stimulated peripheral blood mononuclear cells (PBMCs) culture supernatants, and the percentage and activation of circulating monocytes, as secondary outcomes.

RESULTS

Prune supplementation did not alter hs-CRP, TAC, 8-isoprostane, and plasma cytokine concentrations. However, percent change from baseline in circulating activated monocytes was lower in the 100 g prune/d group compared with the control group (mean ± SD, -1.8% ± 4.0% in 100 g prune/d compared with 0.1% ± 2.9% in control; P < 0.01). Furthermore, in LPS-stimulated PBMC supernatants, the percent change from baseline in TNF-α secretion was lower in the 50 g prune/d group compared with the control group (-4.4% ± 43.0% in 50 g prune/d compared with 24.3% ± 70.7% in control; P < 0.01), and the percent change from baseline in IL-1β, IL-6, and IL-8 secretion was lower in the 100 g prune/d group compared with the control group (-8.9% ± 61.6%, -4.3% ± 75.3%, -14.3% ± 60.8% in 100 g prune/d compared with 46.9% ± 107.4%, 16.9% ± 70.6%, 39.8% ± 90.8% in control for IL-1β, IL-6, and IL-8, respectively; all P < 0.05).

CONCLUSIONS

Dietary supplementation with 50-100 g prunes for 12 mo reduced proinflammatory cytokine secretion from PBMCs and suppressed the circulating levels of activated monocytes in postmenopausal women. This trial was registered at clinicaltrials.gov as NCT02822378.

Links among Obesity, Type 2 Diabetes Mellitus, and Osteoporosis: Bone as a Target

Obesity, type 2 diabetes mellitus (T2DM) and osteoporosis are serious diseases with an ever-increasing incidence that quite often coexist, especially in the elderly. Individuals with obesity and T2DM have impaired bone quality and an elevated risk of fragility fractures, despite higher and/or unchanged bone mineral density (BMD). The effect of obesity on fracture risk is site-specific, with reduced risk for several fractures (e.g., hip, pelvis, and wrist) and increased risk for others (e.g., humerus, ankle, upper leg, elbow, vertebrae, and rib). Patients with T2DM have a greater risk of hip, upper leg, foot, humerus, and total fractures. A chronic pro-inflammatory state, increased risk of falls, secondary complications, and pharmacotherapy can contribute to the pathophysiology of aforementioned fractures. Bisphosphonates and denosumab significantly reduced the risk of vertebral fractures in patients with both obesity and T2DM. Teriparatide significantly lowered non-vertebral fracture risk in T2DM subjects. It is important to recognize elevated fracture risk and osteoporosis in obese and T2DM patients, as they are currently considered low risk and tend to be underdiagnosed and undertreated. The implementation of better diagnostic tools, including trabecular bone score, lumbar spine BMD/body mass index (BMI) ratio, and microRNAs to predict bone fragility, could improve fracture prevention in this patient group.

High-sensitivity C-reactive protein could be a potential indicator of bone mineral density in adolescents aged 10-20 years

There was very limited evidence linking high-sensitivity C-reactive protein (HS-CRP) and total bone mineral density (BMD) in adolescents. The aim of this population-based study was to investigate the relationship between HS-CRP and total BMD in adolescents aged 10-20 years. A cross-sectional study was performed in the normal U.S. population from the data of the National Health and Nutrition Examination Survey (NHANES). The correlation between HS-CRP and total BMD was evaluated by using weighted multivariate linear regression models. And further subgroup analysis was conducted. There were 1747 participants in this study, 47.1% were female, 29.4% were white, 19.5% were black, and 22.3% were Mexican-American. In the multi-regression model that after the potential confounders had been adjusted, HS-CRP was negatively associated with total BMD. The negative association was also observed in the subgroup analyses stratified by gender and age. Our results demonstrated that higher HS-CRP was negatively correlated with total BMD in 10-20 years old adolescents.

Acute Phase Reactions After Intravenous Infusion of Zoledronic Acid in Japanese Patients with Osteoporosis: Sub-analyses of the Phase III ZONE Study

In a clinical trial involving Japanese patients with osteoporosis, post hoc analyses were performed to evaluate the incidence of acute phase reactions (APRs) after infusion of zoledronic acid (ZOL). The results highlighted differences in baseline factors between patients with vs without APRs. Changes in efficacy indicators such as bone turnover markers (BTMs) also showed significant differences. We, therefore, investigated the factors involved in the development of APRs in Japanese patients treated with a once-yearly intravenous infusion of ZOL 5 mg for 2 years by assessing the relation between APRs and efficacy. APRs reported in patients with primary osteoporosis from the ZONE study were analyzed post hoc. Baseline factors were compared in patients with vs without APRs, and changes in BTMs and bone mineral density (BMD) were also investigated. In the ZOL group, 51.2% (169/330) of patients developed APRs after the first infusion and 12.3% (33/268) after the second infusion. Comparison of baseline factors showed that patients without APRs in the ZOL group had a significantly higher neutrophil/lymphocyte ratio, lower serum levels of procollagen type I N-terminal propeptide, older age, and higher likelihood of prior bisphosphonate use vs patients with APRs. Patients with APRs showed significantly higher increases in total hip BMD at 6 and 12 months and larger reductions in BTMs vs patients without APRs. Patient profiles differed significantly between patients with vs without APRs, with APRs after the first infusion of ZOL being related to increases in total hip BMD and suppression of BTMs.This study is registered with ClinicalTrials.gov (identifier: NCT01522521; January 31, 2012).

Increase in C-Reactive Protein Predicts Increase in Rate of Bone Mineral Density Loss: The Study of Women's Health Across the Nation

This longitudinal cohort study's aim was to detect whether larger increases in C-reactive protein (CRP) predict greater amounts of subsequent bone loss in women transitioning from premenopause to postmenopause. Participants were initially 42 to 52 years of age and premenopausal or early perimenopausal. The sample included 1431 women who were not using hormone therapy and whose CRP values were not consistent with acute inflammation. Individual fixed effects (IFE) models estimated the association of log2 CRP with subsequent bone mineral density (BMD) decline rate, adjusted for menopause transition (MT) stage (1: premenopausal or early perimenopausal; 2: late perimenopausal or early postmenopausal; or 3: late postmenopausal), body mass index, diabetes, smoking, alcohol, bone active medications, and anti-inflammatory medications. BMD decline at both the lumbar spine (LS) and femoral neck (FN) was faster for observations made in MT stage 2 than that during other stages (all p < .001). In adjusted IFE models, MT stage modified the relation between increase in CRP and BMD decline rate (interaction p values <.05). Each within-woman doubling of CRP was associated with a 0.09% faster yearly decline in FN BMD in MT stages 1 (p = .006) and 3 (p = .03), and 0.10% faster decline in LS BMD in MT stage 3 only (p = .007). Within-woman increases in CRP in premenopause and early perimenopause and in late postmenopause predict faster BMD decline in the next ~2 years, but the magnitude of CRP's effect is small. © 2021 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

"Inflammaging" and bone in the OsteoLaus cohort

Background

“Inflammaging” is a coined term that combines the processes of inflammation (within the normal range) and aging, since chronic, low-grade, systemic inflammation emerges with increasing age. Unlike high-level inflammation, with which deleterious effects on bone no longer need to be demonstrated, it is unclear whether inflammaging exerts deleterious effects on bone too.

Method

We assessed associations between inflammaging — measured via cytokine levels (high-sensitivity C-reactive protein (hs-CRP); interleukin-1β (IL-1β); interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α)) — and bone parameters (prevalent and incident fractures, bone mineral density (BMD) and trabecular bone score (TBS)) in 1390 postmenopausal women from the OsteoLaus study.

Results

Mean (±SD) age was 64.5 ± 7.6 and mean bone mass index (BMI) 25.9 ± 4.5 kg/m2. Median hs-CRP, IL-1β, IL-6 and TNF-α were 1.4 pg/ml, 0.57 pg/ml, 2.36 pg/ml and 4.82 pg/ml, respectively. In total, 10.50% of the participants had a prevalent, low-impact fracture; and, after 5-years of follow up, 5.91% had an incident, low-impact fracture. Mean T-score BMD was − 1.09 ± 1.53 for the spine, − 1.08 ± 1.02 for the femoral neck, and − 0.72 ± 0.96 for the total hip. Mean spine TBS was 1.320 ± 0.10. We found a positive association between hs-CRP and BMD at all sites, and between hs-CRP and the TBS, but none of these associations were significant after adjustment. We found no association between prevalent or incident fractures and hs-CRP. No association was found between IL-1β, IL6 and TNF-α and BMD, TBS or fractures.

Conclusion

Our results suggest that bone imaging and structure parameters are not associated with the low-grade cytokine levels (within the normal range) observed with inflammaging.

Links between Atherosclerosis and Osteoporosis in Middle Aged and Elderly Men

BACKGROUND

Although the incidences of osteoporosis and atherosclerosis increase with age, there is growing evidence that the coincidental occurrence of both diseases may be independent of age. In general, studies in men are scarce and results are inconsistent.

OBJECTIVE

to investigate the relationship between atherosclerosis and bone mineral density, and the influence of insulin sensitivity and low grade inflammation on this relationship in 332 men without CVD.

METHODS

Aortic Pulse wave velocity (PWV), augmentation index (AIX) and measurements of carotid intima media thickness (CIMT) were assessed. BMD measurements were performed with dual-X-ray absorptiometry (DEXA), subcutaneous fat by ultrasonography. Serum concentrations of lipids, hsCRP, glucose and insulin were measured. Insulin sensitivity was calculated by use of the quantitative insulin sensitivity (QUICKI). We used multivariate linear regression models to examine the association of hsCRP, insulin sensitivity, PWV, Aix, CIMT with BMD.

RESULTS

A higher CIMT was significantly associated with higher BMD after multivariate adjustment (ß 99.7; p=0.02). Further adjustment for weight attenuated the estimates towards non-significant. No association was found between PWV or AIX and BMD. Lower insulin sensitivity was associated with higher BMD (ß -645.1; p<0.01). After adjustment for weight this association was no longer significant. A similar effect was seen for the association between hsCRP and BMD.

CONCLUSION

In this population of healthy, non-obese, men without a history of cardiovascular disease the positively association between cardiovascular parameters and BMD was mainly explained by weight, suggesting that in this population weight plays a protective role in the development of osteoporosis.

Inflammatory Markers and the Risk of Hip and Vertebral Fractures in Men: the Osteoporotic Fractures in Men (MrOS)

Cytokines play major roles in regulating bone remodeling, but their relationship to incident fractures in older men is uncertain. We tested the hypothesis that men with higher concentrations of pro-inflammatory markers have a higher risk of fracture. We used a case-cohort design and measured inflammatory markers in a random sample of 961 men and in men with incident fractures including 120 clinical vertebral, 117 hip, and 577 non-spine fractures; average follow-up 6.13 years (7.88 years for vertebral fractures). We measured interleukin (IL)-6, C-reactive protein (CRP), tumor necrosis factor alpha (TNFα), soluble receptors (SR) of IL-6 (IL-6SR) and TNF (TNFαSR1 and TNFαSR2), and IL-10. The risk of non-spine, hip, and clinical vertebral fracture was compared across quartiles (Q) of inflammatory markers using Cox proportional hazard models with tests for linear trend. In multivariable-adjusted models, men with the highest (Q4) TNFa cytokine concentrations and their receptors had a 2.0-4.2-fold higher risk of hip and clinical vertebral fracture than men with the lowest (Q1). Results were similar for all non-spine fractures, but associations were smaller. There was no association between CRP and IL-6SR and fracture. Men in the highest Q of IL-10 had a 49% lower risk of vertebral fracture compared with men in Q1. Among men with ≥3 inflammatory markers in the highest Q, the hazard ratio (HR) for hip fractures was 2.03 (95% confidence interval [CI] 1.11-3.71) and for vertebral fracture 3.06 (1.66-5.63). The HRs for hip fracture were attenuated by 27%, 27%, and 15%, respectively, after adjusting for appendicular lean mass (ALM), disability, and bone density, suggesting mediating roles. ALM also attenuated the HR for vertebral fractures by 10%. There was no association between inflammation and rate of hip BMD loss. We conclude that inflammation may play an important role in the etiology of fractures in older men. © 2016 American Society for Bone and Mineral Research.

A community-based study of the relationship between coronary artery disease and osteoporosis in Chinese postmenopausal women

BACKGROUND

Menopause is associated with an increased risk for osteoporosis (OP) and coronary artery disease (CAD). The goal of this study was to seek the possible relationship between CAD and OP in Chinese postmenopausal women.

PATIENTS AND METHODS

The total of 1825 participants with complete records were available for data analysis in this study. CAD was diagnosed if any one of the following was present: (i) history and/or treatment for angina and/or myocardial infarction; (ii) history of coronary artery revascularization procedures and/or coronary angiography with 50% or more stenosis in one or more of the major coronary arteries; and (iii) regional wall-motion abnormalities on rest echocardiography. OP was defined as T-score less than -2.5. Multiple regression models after controlling for confounding factors were performed to detect their relationships.

RESULTS

The multiple variable linear regression analyses failed to show a significant association between CAD and T-score. However, the multivariate logistic regression analyses after adjustment for relevant confounding factors detected significant associations between CAD and OP.

CONCLUSION

The present study provided data suggesting that CAD was independently and significantly associated with OP. The prevalence of OP was more frequent in Chinese postmenopausal women with CAD.

Osteoporosis Associated with Chronic Obstructive Pulmonary Disease

Recent epidemiological studies have revealed that osteoporosis is closely associated with common chronic diseases including diabetes, hypertension, chronic kidney disorders, and chronic obstructive pulmonary disease (COPD). COPD is a chronic inflammatory airway disease but now well known to be associated with various systemic comorbidities including osteoporosis. Osteoporosis and osteoporotic fractures are extremely common in COPD patients, which have significant impacts on their quality of life (QOL), activities of daily life (ADL), respiratory function, and possibly their prognosis. COPD-associated osteoporosis is however extremely under-recognized, hence undertreated. Recent studies have suggested that both decreased bone mineral density (BMD) and impaired bone quality compromise bone strength causing fractures in COPD. In COPD patients, various general clinical risk factors for osteoporosis are present including smoking, older age, low body weight, and physical inactivity. In addition, disease-related risk factors such as decreased pulmonary function, inflammation, glucocorticoid use and vitamin D deficiency/insufficiency have been linked to the development of osteoporosis in COPD. Increased awareness of osteoporosis in COPD, especially that of high prevalence of vertebral fractures is called upon among general physicians as well as pulmonologists. Routine screening for osteoporosis and risk assessment of fractures will enable physicians to diagnose COPD patients with comorbid osteoporosis at an early stage. Timely prevention of developing osteoporosis together with appropriate treatment of established osteoporosis may improve QOL and ADL of the COPD patients, preserve their lung function and eventually result in better prognosis in these patients.

Low grade inflammation is associated with lower velocity of sound and broadband ultrasound attenuation in older men, but not with bone loss or fracture risk in a longitudinal aging study

OBJECTIVES

Elevated systemic levels of pro-inflammatory cytokines involved in the pathogenesis of osteoporosis. Our objective was to investigate whether low grade systemic inflammation was associated with bone markers, bone quality, bone mass and fracture risk in a population of older persons.

METHODS

Serum interleukin 6 (IL-6), high-sensitivity C-reactive protein (hsCRP) and erythrocyte sedimentation rate (ESR) were measured in 1287 participants of the Longitudinal Aging Study Amsterdam (LASA), a population based study in a representative sample of older men and women (age 76 ± 6.7 years). Bone quality was measured by quantitative ultrasound measurements (QUS) at baseline and after 3 years at the calcaneus, and bone mineral density was measured by dual-energy X-ray absorptiometry (DXA) at the spine and hip in a subpopulation. Furthermore, the bone markers osteocalcin (OC) and urinary excretion of deoxypyridinoline (DPD) were determined. Incident clinical fractures were recorded during 6 years of follow-up.

RESULTS

Multivariable regression analyses revealed higher IL-6 and ESR levels were associated with lower quantitative ultrasound values in older men (β=-0.98; 95% CI -57.72 to -6.42, p<0.05) and (β=-0.221; 95% CI -15.39 to -3.27, p<0.05) respectively at baseline, but not in women. No significant associations were found between inflammatory markers and bone markers, bone loss at the spine or hips, fracture rate or time to fracture.

CONCLUSION

Elevated inflammatory markers are associated with impaired bone quality in older men, but not in women. No associations were found with the risk for fractures.

High-sensitivity C-reactive protein is an independent risk factor for non-vertebral fractures in women and men: The Tromsø Study

Low-grade inflammation is associated with fractures, while the relationship between inflammation and bone mineral density (BMD) is less clear. Moreover, any gender differences in the sensitivity to inflammation are still poorly elucidated. We therefore tested the hypothesis that high-sensitivity C-reactive protein (CRP) is an independent risk factor for low BMD and non-vertebral fractures, in both genders, and whether there are gender differences in these associations. CRP levels and BMD at the total hip and femoral neck were measured in 1902 women and 1648 men between 55 and 74 years of age, at baseline in the Tromsø Study, Norway, in 2001-2002. Non-vertebral fractures were registered from hospital X-ray archives during an average of 7.2 years follow-up. Linear regression analyses were used for CRP association with BMD and Cox proportional hazards model for fracture prediction by CRP. During 25 595 person-years follow-up, 366 (19%) women and 126 (8%) men suffered a non-vertebral fracture. There was no association between CRP and BMD in women, but an inverse association in men (p=0.001) after adjustment for age and body mass index. Each standard deviation (SD) increase in log-CRP was associated with an increased risk for non-vertebral fracture by 13% in women and 22% in men (hazard ratios (HRs) 1.13, 95% confidence interval (CI) 1.02-1.26, p=0.026 and 1.22, 95% CI=1.00-1.48, p=0.046, respectively). After adjustment for BMD and other risk factors, women with CRP in the upper tertile exhibited 39% higher risk for fracture than those in the lowest tertile of CRP (HR = 1.39, 95% CI = 1.06-1.83, p = 0.017), while men in the upper tertile exhibited 80% higher risk (HR=1.80, 95% CI=1.10-2.94, p=0.019). In summary, CRP was not associated with BMD in women but inversely associated in men, and predicted fractures in both genders. We infer that inflammation influence fracture risk in both women and men, although the biological mechanisms may differ between the genders.

C-reactive protein and risk of fracture: a systematic review and dose-response meta-analysis of prospective cohort studies

This study systematically reviews prospective cohort studies evaluating the relationship between C-reactive protein (CRP) concentrations and subsequent fracture risk. The positive association cannot completely explain the existing evidence, and further studies are needed to demonstrate the shape of the association.

INTRODUCTION

We aimed to perform a systematic review and dose-response meta-analysis of published prospective studies evaluating associations of high-sensitivity CRP (hs-CRP) levels with fracture risk in general populations.

METHODS

We identified relevant studies by searching MEDLINE and EMBASE databases from their inception to May 20, 2014. We included published prospective studies evaluating the associations of hs-CRP levels with risk of fracture in general populations. Two reviewers working independently abstracted the data.

RESULTS

Eight prospective cohort studies involving 34,840 participants and 3,407 incident fracture events were eligible for the present analyses. A meta-analysis of six prospective studies showed that the overall risk for incident fracture in a comparison of individuals in the top tertile with those in the bottom tertile of baseline hs-CRP levels was 2.14 [95% confidence interval (CI) 1.51-3.05, I(2) = 62.3%]. The moderate heterogeneous disappeared when one study was excluded. However, the remaining two studies reported inconsistent results. One study with the biggest sample size showed a U-shaped association for CRP and fracture risk (the association was positive when CRP > 1 mg/L). Similarly, another study reported that per doubling of CRP was positive only when CRP > 3 mg/L.

CONCLUSION

In summary, the present analysis showed that the relationship between CRP concentrations and subsequent fracture risk is still inconsistent. The positive association cannot completely explain the existing evidence, and further larger prospective cohorts with more power are needed to demonstrate the shape of the association, especially for the relatively low CRP concentrations, such as less than 3 mg/L.

Relationship between serum total cholesterol level and serum biochemical bone turnover markers in healthy pre- and postmenopausal women

Background. The presence of common risk factors suggests that there is a relationship between osteoporosis and cardiovascular disease, possibly via dyslipidemia and inflammation. We investigated the relationships among the lipid profile, the inflammation marker high-sensitivity C-reactive protein (hsCRP), bone turnover markers, and bone mineral density (BMD) to assess the correlation between osteoporosis and cardiovascular disease and identify factors predicting osteoporosis. Methods. The study included 759 Korean women older than 20 years of age. The BMD, serum lipid profile, and levels of hsCRP, cross-linked C-terminal peptide (CTX), and osteocalcin were measured. We compared the serum biomarkers between groups with normal and low BMD and assessed the correlations between the levels of bone turnover markers and the lipid profile and hsCRP level. Results. The concentrations of CTX, osteocalcin, and total cholesterol were significantly higher in the low BMD group than in the normal BMD group in premenopausal women group. However, hsCRP was not correlated with these parameters. Multivariate logistic regression analysis revealed that TC (OR, 1.647; 95% CI, 1.190–2.279) and osteocalcin (OR, 1.044; 95% CI, 1.002–1.088) had an increased risk of low BMD in premenopausal women. Conclusions. These results indicate that total cholesterol concentration is correlated with the levels of bone turnover markers, suggesting that it might predict osteoporosis in premenopausal women.

Calcium fructoborate helps control inflammation associated with diminished bone health

Inflammation has been identified as a possible contributory factor to disruption of the normal bone remodeling process, a process essential to healthy bone mineral density. Several large population-based clinical studies have specifically shown that levels of C-reactive protein, an immune recognition protein that is a sensitive marker of inflammation, are inversely and independently associated with total bone mineral density. The evidence suggests that control of C-reactive protein levels may contribute to bone health by protecting against inflammation's disruption of the equilibrium between bone resorption and bone deposition. Calcium fructoborate, a patented complex of calcium, fructose, and boron found naturally in fresh and dried fruits, vegetables and herbs, and wine, is a sugar-borate ester. A growing body of peer-reviewed, published clinical research indicates that the calcium fructoborate significantly reduces serum levels of the C-reactive protein in humans, suggesting that this unique plant-mineral complex may contribute to bone health by controlling the inflammation associated with loss of bone mineral density.

Stress-induced hyperglycemia after hip fracture and the increased risk of acute myocardial infarction in nondiabetic patients

OBJECTIVE

To investigate the risk of acute myocardial infarction (AMI) following stress hyperglycemia after hip fracture.

RESEARCH DESIGN AND METHODS

From February 2007 to February 2012, we carried out a prospective observational analysis of 1,257 consecutive patients with no history of diabetes who suffered hip fractures. Fasting blood glucose (FBG) and glycosylated hemoglobin tests as well as electrocardiography, ultrasonic cardiography, and chest X-ray examinations were performed after admission. All selected hip fracture patients were divided into stress hyperglycemia and non-hyperglycemia groups according to their FBG, and the incidence of AMI was monitored.

RESULTS

Among the patients enrolled, the frequency of stress hyperglycemia was 47.89% (602/1,257) and that of AMI was 9.31% (117/1,257), and the occurrence of AMI in the stress hyperglycemia group was higher than in the non-hyperglycemia group (12.46 vs. 6.41%, P<0.05). In the stress hyperglycemia patients, FBG reached maximum levels at 2-3 days after hip fractures and then decreased gradually. The AMI incidence (62.67% [47/75]) of the stress hyperglycemia group was highest in the initial 3 days after hip fracture, significantly coinciding with the FBG peak time (P<0.05). In all patients with AMI, non-ST-segment elevation myocardial infarction occurred more often than ST-segment elevation myocardial infarction (62.39% [73/117] vs. 37.61% [44/117]).

CONCLUSIONS

Stress-induced hyperglycemia after hip fracture increased the risk of AMI.

Should we abandon statins in the prevention of bone fractures?

Osteoporosis increases dramatically with age. About 40 % of women in developed countries will experience an osteoporosis-related fracture in the course of their lifetime, with men experiencing approximately one-third to one-half the risk of women. The "lipid hypothesis of osteoporosis" claims for a role of oxidized lipids as a contributing factor in osteoporosis. On the other hand, statins are supposed to exert anabolic effects on the bone, either through their lipid-lowering action or signal pathways that are independent of their effects on lipid levels. The epidemiological evidence seems to suggest that higher triglycerides may give some protection against fracture, although no association with reduced fracture risk has been reported between lipid-lowering drug (except statins) users and non-users. The epidemiological evidence for a role of statins in osteoporosis is strong, with a lower fracture risk ranging from 30 to 40 % in statin users versus non-users. However, some pitfalls inherent to observational studies (high heterogeneity, residual confounding, potential publication bias) and the lack of association in randomized trials suggest caution. At the moment, the evidence for a role of statins in prevention of osteoporosis is insufficient to recommend starting statin therapy with the aim to prevent osteoporosis.

Association between metabolic syndrome and bone loss at various skeletal sites in postmenopausal women: a 3-year retrospective longitudinal study

Although the presence of metabolic syndrome (MetS) and increasing numbers of MetS components were associated with attenuated bone loss at various skeletal sites in postmenopausal women, this beneficial effect of MetS on bone mass can be mainly explained by higher mechanical loading in the affected subjects.

INTRODUCTION

Previous cross-sectional epidemiological studies reported the inconsistent results regarding the combined effects of MetS on bone mass. In our present report, we performed a large, longitudinal study to evaluate MetS in relation to annualized bone mineral density (BMD) changes in postmenopausal Korean women.

METHODS

The study cohort consisted of 1,218 postmenopausal women who had undergone comprehensive routine health examinations with an average follow-up interval of 3 years. The BMD at the lumbar spine and proximal femur sites was measured with dual-energy X-ray absorptiometry using the same equipment at baseline and at follow-up.

RESULTS

Following adjustment for age, baseline BMD, and lifestyle factors, the women with MetS had 21.7, 17.0, 26.7, and 31.1 % less bone loss at the total femur, femur neck, trochanter, and lumbar spine, respectively, compared with MetS-free women (P = 0.004 to 0.041). Consistently, the rates of bone loss at all skeletal sites were linearly attenuated with increasing numbers of MetS components (P = 0.004 to <0.001). Importantly, when weight and height were added as confounding factors, the differences and trends of annualized BMD changes according to the MetS status disappeared.

CONCLUSION

Our current results indicate that the beneficial effects of MetS on bone mass can be mainly explained by higher mechanical loading in the affected subjects. Consequently, MetS per se may not be a meaningful concept for predicting future bone loss and for explaining associations between osteoporosis and cardiovascular diseases.

C-reactive protein, bone strength, and nine-year fracture risk: data from the Study of Women's Health Across the Nation (SWAN)

Higher levels of C-reactive protein (CRP), an inflammatory marker, are associated with increased fracture risk, although previous studies on CRP and bone mineral density (BMD) have yielded conflicting results. We aimed to test the hypotheses that composite indices of femoral neck strength relative to load, which are inversely associated with fracture risk, would also be inversely associated with CRP, and would explain part of the association between CRP and fracture risk. We analyzed data from a multisite, multiethnic prospective cohort of 1872 community-dwelling women, premenopausal or early perimenopausal at baseline. Femoral neck composite strength indices in three failure modes were calculated using dual-energy X-ray absorptiometry (DXA)-derived femoral neck width (FNW), femoral neck axis length (FNAL), femoral neck BMD and body size at baseline, as BMD*FNW/weight for compression strength, BMD*(FNW)(2) /(FNAL*weight) for bending strength, and BMD*FNW*FNAL/(height*weight) for impact strength. Incident nondigital, noncraniofacial fractures were ascertained annually over a median follow-up of 9 years. In analyses adjusted for age, race/ethnicity, diabetes, menopause transition stage, body mass index, smoking, alcohol use, physical activity, medications, prior fracture, and study site, CRP was associated inversely with each composite strength index (0.035-0.041 SD decrement per doubling of CRP, all p < 0.001), but not associated with femoral neck or lumbar spine BMD. During the follow-up, 194 women (10.4%) had fractures. In Cox proportional hazards analyses, fracture hazard increased linearly with loge (CRP), only for CRP levels ≥ 3 mg/L. Addition of femoral neck or lumbar spine BMD to the model did not attenuate the CRP-fracture association. However, addition of any of the composite strength indices attenuated the CRP-fracture association and made it statistically nonsignificant. We conclude that fracture risk increases with increasing CRP, only above the threshold of 3 mg/L. Unlike BMD, composite strength indices are inversely related to CRP levels, and partially explain the increased fracture risk associated with inflammation.

Relationship of adiposity to bone volumetric density and microstructure in men and women across the adult lifespan

Recent evidence suggests that adipose tissue may negatively impact bone health, challenging the traditional paradigm that increased fat mass, through mechanical loading or endogenous estrogen production, is beneficial to the skeleton. We hypothesized that it is primarily the visceral compartment of body fat that is detrimental to bone metabolism, resulting in impaired bone density and architecture. In an age-stratified population sample of 218 women and 291 men (age 20-97 years), we assessed visceral (VAT) and subcutaneous (SAT) adipose tissue areas at the L2-L3 interspace level by single slice quantitative computed tomography (QCT) and measured total body fat mass (TBF) by dual-energy X-ray absorptiometry. We then correlated these findings with volumetric bone mineral density (vBMD) at the femoral neck (FN) and lumbar spine (LS) assessed by central QCT, and with vBMD and microstructural parameters at the ultradistal radius (UDR) by high resolution peripheral QCT (HRpQCT). In unadjusted analyses in postmenopausal women, TBF and SAT were positively correlated with total, trabecular, and cortical vBMD at the FN, LS, and UDR and with trabecular microstructure at the UDR. By contrast, VAT was not correlated with vBMD at the FN or LS but was positively correlated with UDR total and trabecular vBMD but not cortical vBMD. Adjustment for age or for bioavailable estradiol and testosterone levels reduced these correlations, while adjustment for body weight eliminated most positive associations. Assessment of the VAT/SAT ratio, however, demonstrated a negative relationship with vBMD at the FN and LS in postmenopausal women, a relationship eliminated when adjusted for age. Correlations between skeletal parameters and adipose measurements in pre-menopausal women and older men were weaker and mostly non-significant. In younger men, VAT was negatively associated with vBMD, cortical thickness, and trabecular microstructure at the UDR, and with LS vBMD and FN cortical vBMD. These associations generally remained after adjustment, with some negative associations (e.g., UDR cortical area) being accentuated. Similar results were found when the VAT/SAT ratio was correlated with FN vBMD in younger men; in contrast, VAT/SAT was positively correlated with FN vBMD in older men and this relationship was strengthened by age-adjustment. Together, our data suggest that adiposity has associations with bone that are age-, gender-, menopausal status-, adipose depot-, and bone compartment-specific. These novel observations warrant further investigations to establish any causal relationships.

Acute effects of glucocorticoids on serum markers of osteoclasts, osteoblasts, and osteocytes

The aim of this study was to investigate the acute effects of oral glucocorticoids in doses used in clinical practice on biochemical indices of the function of osteoclasts, osteoblasts, and osteocytes. In 17 adult patients suffering from various medical pathologies requiring systemic steroid therapy that were never before treated with glucocorticoids, glucocorticoid treatment was initiated (mean prednisolone equivalent dose of 23.1 ± 12.7 mg/day, range 10-50). Fasting morning serum concentrations of osteocalcin (OC), amino-terminal propeptide of type I procollagen (PINP), type 1 collagen cross-linked C-telopeptide (βCTX), soluble receptor activator of nuclear factor kappaB ligand (sRANKL), osteoprotegerin (OPG), sclerostin, Dickkopf-1 (Dkk-1), and high-sensitivity C-reactive protein (hsCRP) were measured at baseline and on three consecutive days. Significant reductions in serum OC, PINP, OPG, sclerostin, and hsCRP were observed during 96 h of glucocorticoid administration, while serum βCTX showed a significant percentual increase. A significant positive correlation was found between serum concentrations of Dkk-1 and βCTX after 96 h of treatment with glucocorticoids. A significant drop in serum sclerostin, OPG, and OC observed in this study may reflect the rapid glucocorticoid-induced apoptosis of osteocytes.

Hip fracture and risk of acute myocardial infarction: a nationwide study

Osteoporotic fractures are associated with increased mortality risk. However, little data are available on the risk of acute myocardial infarction (AMI) after hip fracture. Therefore, we investigated whether hip fracture increased the risk of AMI in a large, nationwide cohort study. We obtained data from 8758 patients diagnosed with hip fracture from 2000 to 2009 and from 4 matched controls for each patient from the Longitudinal Health Insurance Database (LHID 2000), Taiwan. Controls were matched for age, sex, comorbid disorders, and enrollment date. All subjects were followed up from the date of enrollment until AMI, death, or the end of data collection (2009). Cox's regression model adjusted for age, sex, comorbid disorders, and medication was used to assess independent factors determining the risk of development of AMI. As expected, despite the matching, the hip fracture patients had more risk factors for AMI at baseline. A total of 8758 subjects with hip fractures and 35,032 controls were identified. Among these patients, 1183 (257 hip fracture patients and 926 controls) developed AMI during the median 3.2-year (interquartile range 1.4 to 5.8 years) follow-up period. Patients with hip fractures had a higher incidence of AMI occurrence when compared with controls (8.7/1000 person-years versus 6.82/1000 person-years). Multivariate analysis adjusted for baseline covariates indicated that hip fracture was associated with a greater risk for AMI development (hazard ratio [HR] = 1.29; 95% confidence interval [CI] 1.12-1.48; p < 0.001). We conclude that hip fracture is independently associated with a higher risk of subsequent AMI.

Low-grade systemic inflammation and suboptimal bone mineral density throughout adolescence: a prospective study in girls

OBJECTIVE

We aimed at quantifying the associations between high-sensitivity C-reactive protein (hs-CRP) and forearm bone mineral density (BMD) throughout adolescence in overweight and normal-weight girls.

DESIGN

Prospective cohort study.

PATIENTS

346 girls born in 1990 and attending schools in Porto, Portugal.

MEASUREMENTS

Adolescents were evaluated at 13 and 17 years of age using a standard protocol. Forearm BMD was measured by dual-energy X-ray absorptiometry. Anthropometric assessment included weight, height, body fat percentage and waist circumference. Girls were categorized according to age- and sex-specific body mass index (BMI) percentiles as normal weight in both evaluations or overweight in at least one assessment. Pubertal development was estimated using menarche age. Serum hs-CRP was determined using particle-enhanced immunonephelometry. Hs-CRP was log-transformed, and associations were quantified using linear regression coefficients and 95% confidence intervals (95%CI).

RESULTS

An inverse association between hs-CRP and BMD was observed from 13 years of age in overweight girls [-11·26 mg/cm(2) (-21·99, -0·52)]. Among normal-weight adolescents, 13-year-old hs-CRP was negatively associated with prospective BMD variation between 13 and 17 years of age [-1·90 mg/cm(2) year (-3·35, -0·45)]. Overweight girls who maintained higher levels of hs-CRP throughout adolescence had lower 17-year-old BMD (adjusted mean 0·441 vs 0·483 g/cm(2) in those who remained with lower levels of hs-CRP). At 17 years of age, significant inverse associations were found between hs-CRP and BMD among normal-weight and overweight girls.

CONCLUSIONS

Obesity-related early systemic inflammation might be involved in suboptimal bone accrual, particularly in overweight girls.

Poor trabecular microarchitecture at the distal radius in older men with increased concentration of high-sensitivity C-reactive protein--the STRAMBO study

Low-grade inflammation, assessed by serum high-sensitivity C-reactive protein (hsCRP) concentration, is associated with higher fracture risk irrespective of areal bone mineral density (aBMD). We assessed the association of hsCRP with bone microarchitecture (measured by high-resolution pQCT) at the distal radius and tibia in 1,149 men, aged 19-87 years. hsCRP concentration increased with age until the age of 72, then remained stable. aBMD was not correlated with hsCRP level. After adjustment for confounders, bone microarchitecture was not associated with hsCRP level in men aged <72. After the age of 72, hsCRP >5 mg/L was associated with lower trabecular density, lower trabecular number, higher trabecular spacing, and more heterogeneous trabecular distribution (p < 0.05-0.005) at the distal radius versus hsCRP ≤ 5 mg/L. Similar differences were found for the fourth hsCRP quartile (>3.69 mg/L) versus the three lower quartiles combined. Cortical parameters of distal radius and microarchitectural parameters of distal tibia did not vary according to hsCRP concentration in men aged ≥ 72. Fracture prevalence increased with increasing hsCRP level. After adjustment for confounders (including aBMD), odds for fracture were higher in men with hsCRP >5 mg/L compared to hsCRP <1 mg/L (OR = 2.22, 95 % CI 1.29-3.82) and did not change after additional adjustment for microarchitectural parameters. The association between hsCRP level and bone microarchitecture was observed only for trabecular parameters at the radius in men aged ≥72. Impaired bone microarchitecture does not seem to explain the association between elevated CRP level and higher risk of fracture.

Centrally located body fat is associated with lower bone mineral density in older Puerto Rican adults

BACKGROUND

Fat mass is thought to be protective against osteoporosis, primarily because of its weight-bearing effect. Few studies have evaluated the association between abdominal fat mass (AFM) and bone health beyond its weight-bearing effect.

OBJECTIVE

We tested the hypothesis that higher body weight-adjusted AFM is associated with poor bone health.

DESIGN

A cross-sectional study was conducted in 629 Puerto Rican adults aged 47-79 y. Bone mineral density (BMD) of the femoral neck, trochanter, total femur, and lumbar spine (L2-L4) were measured by using dual-energy X-ray absorptiometry (DXA). AFM and total fat mass (TFM) were assessed by using body-composition software from whole-body DXA scans. Osteoporosis and osteopenia were defined as T-scores ≤ -2.5 and -1.0 to -2.5 SD, respectively, at the respective bone site.

RESULTS

After confounders were controlled for, body weight-adjusted AFM was inversely associated with BMD at all 4 bone sites in women and at the femoral neck in men. For TFM, small inverse associations were seen at the trochanter and total femur in women. In men, similar associations were seen at the 3 femur sites. In both sexes, the odds for osteoporosis or osteopenia at each of the femoral sites increased by 10-16% for every 100-g increase in body weight-adjusted AFM.

CONCLUSIONS

Higher AFM was associated with poor bone health in this Puerto Rican sample. Efforts to reduce abdominal obesity will not only reduce the risk of chronic disease but may also improve bone health. This trial is registered at clinicaltrials.gov as NCT01231958.

Coexistence of osteoporosis (OP) and coronary artery disease (CAD) in the elderly: it is not just a by chance event

Cardiovascular disease (CVD) and OP are common age-related conditions. In both cross-sectional and longitudinal epidemiologic studies, low bone mass has been related to increased frequency of CVD. But available data in geriatric population is limited. In this study we aimed to seek the possible relationship between CAD and low bone mineral density (BMD) in a large number of geriatric patients. A total of 2235 patients aged 65 years or more were included in this cross-sectional study. All patients underwent a complete geriatric assessment and evaluated for CAD and cardiovascular risk factors. BMD was measured by dual-energy X-ray absorptiometry at the lumbar spine (L1-L4) and femoral neck. BMD results were classified into three groups; normal (T-score: ≥-1.0×S.D.), osteopenia (T-score between -1.0 and -2.5×S.D.), and OP (T-score: ≤-2.5×S.D.). CAD was present in 397 (29.7%) of 1335 patients with OP, in 199 (27.4%) of 726 patients with osteopenia and in 34 (19.5%) of 174 patients with normal BMD. Multivariate regression analysis revealed that presence of OP or osteopenia increased the prevalence of CAD as an independent correlate (OR=1.643; 95% CI=1.068-2.528, p=0.030). This study highlights the need for careful evaluation of elderly patients with low BMD for possible CAD.

C-reactive protein predicts incident fracture in community-dwelling elderly Japanese women: the Muramatsu study

SUMMARY

In a 6-year cohort study of 751 community-dwelling elderly Japanese women, we found that C-reactive protein (CRP) is a significant predictor of osteoporotic fracture in elderly Asian women, who have significantly lower CRP levels than Caucasians. Mechanisms explaining such an association should be further studied.

INTRODUCTION

While CRP, a systemic inflammation marker, is thought to be associated with osteoporosis, evidence supporting this claim has been limited. We aimed to assess the association between CRP levels and incident osteoporotic fracture in elderly women.

METHODS

We conducted a cohort study with a follow-up period of 6 years. The study included 751 Japanese women aged 69 years or older. We measured serum high-sensitivity CRP (hs-CRP) levels as a major predictor. Covariates included age, body mass index, forearm bone mineral density, calcium intake, serum 25-hydroxyvitamin D, postural sway, osteoporosis medication, and physical activity. The primary outcome was incident limb and vertebral fractures. The Cox proportional hazards model was used to calculate the hazard ratio (HR) of fracture.

RESULTS

Median hs-CRP values in study participants were 0.16 mg/L in the lowest tertile, 0.36 mg/L in the medium tertile, and 1.14 mg/L in the highest tertile. The hs-CRP values in these women were substantially lower than in their Caucasian counterparts. Limb or vertebral fractures occurred in 50 subjects during 4,250 person-years. Low CRP levels were associated with low incidence of limb or vertebral fractures (P for trend = 0.035). The adjusted HRs of fracture for the medium and highest quartiles of hs-CRP levels, compared to the lowest quartile, were 2.22 (95% CI, 1.02-4.84) and 2.40 (95% CI, 1.10-5.24), respectively.

CONCLUSIONS

CRP is a significant predictor of osteoporotic fracture in elderly Asian women who have substantially lower CRP levels than Caucasians. Mechanisms explaining such an association should be further studied.

Using tetracyclines to treat osteoporotic/osteopenic bone loss: from the basic science laboratory to the clinic

Periodontitis (progressive inflammatory disease characterized by alveolar bone loss, a major cause of tooth loss worldwide) is associated with both systemic osteoporosis and its milder form, osteopenia. Tetracyclines, by virtue of their non-antimicrobial pro-anabolic and anti-catabolic properties, are excellent candidate pharmaceuticals to simultaneously treat these local and systemic disorders. This paper reviews the foundational basic science and translational research which lead to a pivotal multicenter randomized clinical trial in postmenopausal women with both periodontitis and systemic (skeletal) osteopenia. This trial was designed primarily to examine whether subantimicrobial dose doxycycline (SDD) could reduce progressive alveolar (oral) bone loss associated with periodontitis and, secondarily, whether SDD could reduce systemic bone loss in the same subjects. This paper describes the efficacy and safety findings from this clinical trial and also outlines future directions using this promising and novel approach to manage both oral and systemic bone loss.

Proinflammatory cytokines and osteoporosis

Experimental studies indicate that the proinflammatory cytokines interleukin-1, interleukin-6, and tumor necrosis factor-alpha are important regulators of bone resorption and may play an important role in age- and estrogen deficiency-related bone loss. Although the observation of accelerated bone loss in patients with inflammatory disorders supports this mechanism, the role of cytokines in the etiology of osteoporosis has yet to be determined. Elucidation of this potential relationship could not only provide clinicians with an additional tool to identify patients at risk for osteoporosis, but may also inform the development of cytokine-blocking therapies as potential interventions to curb bone loss. Although some epidemiologic studies suggest increases in proinflammatory cytokines are associated with decreased bone mass and greater fracture risk, the totality of evidence is limited and provides no clear indication of which cytokines may be most important for bone health. Additional studies are required to establish if inflammation is an important risk factor for osteoporosis.

Relationships among serum receptor of nuclear factor-kappaB ligand, osteoprotegerin, high-sensitivity C-reactive protein, and bone mineral density in postmenopausal women: osteoimmunity versus osteoinflammatory

OBJECTIVE

The aim of this study was to investigate the correlations among circulating osteoprotegerin (OPG), the receptor activator of nuclear factor-kappaB ligand (RANKL), high-sensitivity C-reactive protein (hsCRP), and bone mineral density (BMD) in healthy postmenopausal women.

METHODS

In a population-based study, highly specific enzyme-linked immunosorbent assay methods were used to evaluate the sera of 382 healthy Iranian postmenopausal women (mean age +/- SD, 58.7 +/- 7.5 y) for RANKL, OPG, hsCRP, degradation products of C-terminal telopeptides of type I collagen, and osteocalcin. BMD was determined for the lumbar spine (L2-L4) and the proximal femur using dual-energy x-ray absorptiometry.

RESULTS

Circulating levels of OPG (r = 0.30, P < 0.001) and the RANKL/OPG ratio (r = -0.17, P < 0.001) were significantly associated with age. The geometric mean of hsCRP was 1.89 mg/L (SE, 1.05) in the population studied. There was a significant correlation between log(hsCRP) levels and body mass index (BMI; r = 0.36, P < 0.001). Multivariate linear analyses revealed that age (beta = -0.295, P < 0.001), BMI (beta = 0.464, P < 0.001), RANKL (beta = -0.105, P = 0.014), and OPG (beta = 0.098, P = 0.029) were the independent determinants for lumbar BMD (R(2) = 0.35). Age (beta = -0.250, P < 0.001), BMI (beta = 0.486, P < 0.001), and RANKL (beta = -0.110, P = 0.009) were independently correlated with femoral neck BMD (R(2) = 0.36). Age- and BMI-adjusted analysis by quartiles of log-transformed hsCRP did not reveal an association with BMD, serum levels of biochemical markers of bone turnover, RANKL, or OPG.

CONCLUSIONS

The circulating levels of the RANKL/OPG osteoimmunity system have an association with BMD, but subclinical systemic inflammation may not be involved in bone mass in healthy postmenopausal women.

Increased bone resorption is associated with increased risk of cardiovascular events in men: the MINOS study

Better assessment of the association between cardiovascular disease and osteoporosis in older men may help identify shared etiologies for bone and heart health in this population. We assessed the association of BMD and bone turnover markers (BTMs) with risk of cardiovascular events (myocardial infarction or stroke) in 744 men >or=50 yr of age. During the 7.5-yr prospective follow-up, 43 strokes and 40 myocardial infarctions occurred in 79 men. After adjustment for confounders (age, weight, height, smoking, education, physical activity, self-reported history of diabetes, hypertension, and prevalent ischemic heart disease), men in the lowest quartile of BMD at the spine, whole body, and forearm had a 2-fold increased risk of cardiovascular events. Men in the highest quartile of bone resorption markers (deoxypyridinoline [DPD], C-telopeptide of type I collagen) had a 2-fold increased risk of cardiovascular events (e.g., multivariable-adjusted hazard ratio [including additional adjustment for BMD] was 2.11 [95% CI: 1.26-3.56], for the highest quartile of free DPD relative to the lowest three quartiles). The results were similar for men without prevalent ischemic heart disease and for myocardial infarction and stroke analyzed separately. Our data suggest that men with low BMD or high bone resorption may be at increased risk of myocardial infarction and stroke in addition to fracture. Thus, men with osteoporosis may benefit from screening for cardiovascular disease. Further study to elucidate the biological mechanism shared by bone and vascular disease may help efforts to identify men at risk or develop treatment.

Atherosclerosis and osteoporosis: age-dependent degenerative processes or related entities?

Osteoporosis and atherosclerosis, two multifactorial and degenerative entities, are major public health problems. These diseases accompany the aging process and share common risk factors. Furthermore, several common pathophysiological factors have been suggested. These include similar molecular pathways involving bone and vascular mineralization, estrogen deficiency, parathyroid hormone, homocysteine, lipid oxidation products, inflammatory process, as well as vitamin D and K. Moreover, the use of statins, biphosphonates, beta-blockers and experimental dual-purpose therapies based on the biological linkage of the above entities may simultaneously benefit bone loss and vascular disease. This review considers a potential link between osteoporosis and atherosclerosis beyond aging. These common factors may lead to appropriate treatment strategies.

Subantimicrobial-dose doxycycline modulates gingival crevicular fluid biomarkers of periodontitis in postmenopausal osteopenic women

BACKGROUND

We recently demonstrated that a 2-year subantimicrobial-dose doxycycline (SDD) regimen (double-masked, placebo-controlled clinical trial) in postmenopausal (PM) women exhibiting mild systemic bone loss (osteopenia) and local bone loss (periodontitis) reduced the progression of periodontal attachment loss (intent-to-treat analysis) and the severity of gingival inflammation and alveolar bone loss (subgroups) without producing antibiotic side effects. We now describe SDD effects on biomarkers of collagen degradation and bone resorption in the gingival crevicular fluid (GCF) of the same vulnerable subjects.

METHODS

GCF was collected from SDD- and placebo-treated PM subjects (n=64 each) at the baseline and 1- and 2-year appointments; the volume was determined; and the samples were analyzed for collagenase activity (using a synthetic peptide as substrate), relative levels of three genetically distinct collagenases (Western blot), a type-1 collagen breakdown product/bone resorption marker (a carboxyterminal telopeptide cross-link fragment of type I collagen [ICTP]; radioimmunoassay), and interleukin-1beta (enzyme-linked immunosorbent assay). Statistical analyses were performed using generalized estimating equations; primary analyses were intent-to-treat.

RESULTS

Collagenase activity was significantly reduced by SDD treatment relative to placebo based on intent-to-treat (P=0.01). ICTP showed a similar pattern of change during SDD treatment, and GCF collagenase activity and ICTP were positively correlated at all time periods (P<0.001). Matrix metalloproteinase (MMP)-8 accounted for approximately 80% of total collagenase in GCF, with much less MMP-1 and -13, and SDD reduced the odds of elevated MMP-8 by 60% compared to placebo (P=0.006).

CONCLUSION

These observations support the therapeutic potential of long-term SDD therapy to reduce periodontal collagen breakdown and alveolar bone resorption in PM women; effects on serum biomarkers of systemic bone loss in these subjects are being analyzed.

Elevated serum alkaline phosphatase and peripheral arterial disease in the United States National Health and Nutrition Examination Survey 1999-2004

BACKGROUND

Alkaline phosphatase (ALP) is elevated in peripheral arterial disease (PAD). We therefore examined the relationship of PAD with ALP and other liver enzymes in the United States National Health and Nutrition Examination Survey 1999-2004.

METHODS

The analysis included 5995 men and non-pregnant women aged >or=40 years with no missing data in variables of interest. PAD was defined as ankle-brachial blood pressure index (ABI) <0.90 in either leg.

RESULTS

Serum alkaline phosphatase (ALP) level was associated significantly with lower ABI after adjustment for confounding factors (p=0.019). No significant association of ABI with other liver enzymes was found. Serum ALP level increased with increasing age, body mass index, C-reactive protein, monocyte count, serum uric acid, lead, cadmium, and prevalence of hypercholesterolemia, diabetes, smoking, non-alcohol drinking, and cardiovascular diseases after adjusting for age, sex, race/ethnicity, and survey years (p<0.02). The highest quartile of serum ALP was associated with an odds ratio of 1.89 (95% confidence interval [CI]: 1.25-2.85) for PAD after adjustment for confounding factors (p for trend=0.023). In subjects with normal kidney function (glomerular filtration rate >90 ml/min/1.73 m(2)), the odds ratio increased to 4.22 (95% CI 1.45-12.35) (p=0.010).

CONCLUSION

Elevated serum ALP is correlated with PAD, independent of other traditional cardiovascular risk factors.

Circulating levels of inflammatory markers predict change in bone mineral density and resorption in older adults: a longitudinal study

CONTEXT

IL-1, IL-6, and TNF-alpha play an important role in the pathogenesis of osteoporosis in animals; however, evidence that these play a similar role in bone loss in human studies is limited.

OBJECTIVE

Our objective was to determine the associations between serum markers of inflammation and changes in bone mineral density (BMD) and urinary pyridinoline (PYR) to creatinine (Cr) ratio over 2.9 yr in older adults.

METHODS

A total of 168 randomly selected subjects (mean 63 yr, range 52-78, 48% female) was studied. BMD was measured by dual-energy x-ray absorptiometry at baseline (mean T score: -0.18 to -0.61) and 2.9 yr later. Serum high-sensitivity (hs) C-reactive protein (CRP), IL-6, TNF-alpha, and the urinary PYR/Cr ratio were measured on both occasions.

RESULTS

The mean annual loss of BMD was 0.15, 0.15, and 0.34% at total body, spine, and hip, respectively. Change in total body BMD was associated with baseline hs-CRP, IL-6, and TNF-alpha, as well as change in hs-CRP (beta: -0.41%/U, 95% confidence interval -0.68%, -0.15%) and IL-6 (beta: -0.62%/U, 95% confidence interval -1.01%, -0.23%). If these markers were put in the same predictive model, only IL-6 remained largely unchanged. Changes in other BMD sites were significantly predicted by IL-6 (hip and spine) and TNF-alpha (spine only). Finally, change in the PYR/Cr ratio was positively associated baseline IL-6, hs-CRP, and their changes (all P < 0.05) in women, but not men.

CONCLUSIONS

Variation within the low levels of inflammatory markers observed in this study, especially IL-6, predicts bone loss and resorption, suggesting that targeted antiinflammatory therapy has potential for the prevention of osteoporosis.

Altered bone metabolism in inflammatory disease: role for nutrition

Osteoporosis is a major public health problem, and as life expectancy and the world's population continue to increase will become even more important. Thus, there is an urgent need to develop and implement nutritional approaches and policies for the prevention and treatment of osteoporosis. Patients with some chronic inflammatory diseases appear to be more likely to develop osteopenia, and in some cases earlier in life, which is of particular concern as the incidence of inflammatory diseases in the Western world is increasing. While the cause of bone loss in patients with inflammatory disease is multifactorial, nutrition may have a role. Many of these patients may have one or more nutritional deficiencies, which can lead to altered rates of bone metabolism. On the other hand, some nutritional factors may attenuate the inflammatory process itself, and thus may indirectly benefit bone metabolism and bone health in patients with inflammatory disease. The present review will consider these issues, particularly in the context of inflammatory bowel disease, coeliac diease and atherosclerosis.