The relationship between incidence of fractures and anemia in older multiethnic women

Sex differences in hemoglobin levels and five-year refracture risk in patients with osteoporotic fractures: a retrospective cohort analysis

We conducted a retrospective cohort analysis to examine the association between hemoglobin (Hb) levels and refracture risk in elderly patients with osteoporotic fractures (OPFs). Our findings suggest a nonlinear relationship exists in females, and females with Hb levels below 10.7 g/dL may be at a higher risk of refracture.

INTRODUCTION

Hematopoiesis and bone health have a reciprocal influence on each other. Nevertheless, there is a scarcity of in-depth research on the association between Hb levels and the occurrence of fractures. The present research aimed to investigate the correlation between Hb levels and the rate of refracture within 5 years among individuals with OPFs.

METHODS

A retrospective cohort analysis was undertaken between 2017 and 2022. The study included 1906 individuals who were inhabitants of Kunshan and were over 60 years old. These individuals had experienced an OPF between January 1, 2017, and July 27, 2022, resulting in their hospitalization. Cox proportional hazard regression models were used to evaluate the risk of refracture within 5 years based on the Hb levels acquired during the admission examination, with consideration for sex differences. A nonlinear relationship was identified using smoothed curve fitting and threshold analysis. Kaplan-Meier curves were used to compare refracture rates between patients with low and high Hb levels.

RESULTS

Elderly female patients with OPFs and lower Hb levels exhibited a significantly higher risk of a 5-year refracture. Conversely, no significant associations were observed between the two variables in male patients. A nonlinear correlation was found between Hb levels and the probability of refracture in females, with a turning point identified at 10.7 g/dL of Hb levels. A strong negative association was observed with the five-year refracture rate when Hb levels fell below 10.7 g/dL (hazard ratio (HR) = 0.63; 95% confidence interval (CI) 0.48 to 0.83; P-value = 0.0008). This finding suggests that for every 1 g/dL increase in Hb below 10.7 g/dL, the risk of refracture reduced by 37%. However, no statistically significant association was observed when Hb levels were above 10.7 g/dL.

CONCLUSIONS

The findings demonstrated a significant negative correlation between Hb levels and the likelihood of refracture in elderly female patients with OPFs and suggested that elderly females with recent OPFs and Hb levels below 10.7 g/dL may be at a higher risk of refracture. Additionally, the Hb levels can serve as an indicator of bone fragility in elderly female patients with OPFs. These findings highlight the importance of monitoring Hb levels as a part of comprehensive management strategies to both assess skeletal health and prevent refractures in this population.

Iron and bones: effects of iron overload, deficiency and anemia treatments on bone

Iron is a vital trace element and exerts opposing effects on bone in both iron overload and iron deficiency situations. Remarkably, iron supplementation through intravenous infusion in patients with iron deficiency can also have detrimental effects on bone in special cases. The diverse mechanisms underlying these effects and their manifestations contribute to the complexity of this relationship. Iron overload impacts both bone resorption and formation, accelerating bone resorption while reducing bone formation. These effects primarily result from the direct action of reactive oxygen species (ROS), which influence the proliferation, differentiation, and activity of both osteoclasts and osteoblasts differently. This imbalance favors osteoclasts and inhibits the osteoblasts. Simultaneously, multiple pathways, including bone morphogenic proteins, RANK ligand, and others, contribute to these actions, leading to a reduction in bone mass and an increased susceptibility to fractures. In contrast, iron deficiency induces low bone turnover due to energy and co-factor deficiency, both of which require iron. Anemia increases the risk of fractures in both men and women. This effect occurs at various levels, reducing muscular performance and, on the bone-specific level, decreasing bone mineral density. Crucially, anemia increases the synthesis of the phosphaturic hormone iFGF23, which is subsequently inactivated by cleavage under physiological conditions. Thus, iFGF23 levels and phosphate excretion are not increased. However, in specific cases where anemia has to be managed with intravenous iron treatment, constituents-particularly maltoses-of the iron infusion suppress the cleavage of iFGF23. As a result, patients can experience severe phosphate wasting and, consequently, hypophosphatemic osteomalacia. This condition is often overlooked in clinical practice and is often caused by ferric carboxymaltose. Ending iron infusions or changing the agent, along with phosphate and vitamin D supplementation, can be effective in addressing this issue.

Hemoglobin Levels Improve Fracture Risk Prediction in Addition to FRAX Clinical Risk Factors and Bone Mineral Density

CONTEXT

Anemia and decreasing levels of hemoglobin (Hb) have previously been linked to increased fracture risk, but the added value to FRAX, the most utilized fracture prediction tool worldwide, is unknown.

OBJECTIVE

To investigate the association between anemia, Hb levels, bone microstructure, and risk of incident fracture and to evaluate whether Hb levels improve fracture risk prediction in addition to FRAX clinical risk factors (CRFs).

METHODS

A total of 2778 community-dwelling women, aged 75-80 years, and part of a prospective population-based cohort study in Sweden were included. At baseline, information on anthropometrics, CRFs, and falls was gathered, blood samples were collected, and skeletal characteristics were investigated using dual-energy x-ray absorptiometry and high-resolution peripheral quantitative computed tomography. At the end of follow-up, incident fractures were retrieved from a regional x-ray archive.

RESULTS

The median follow-up time was 6.4 years. Low Hb was associated with worse total hip and femoral neck bone mineral density (BMD), and lower tibia cortical and total volumetric BMD, and anemia was associated with increased risk of major osteoporotic fracture (MOF; hazard ratio 2.04; 95% CI 1.58-2.64). Similar results were obtained for hip fracture and any fracture, also when adjusting for CRFs. The ratio between 10-year fracture probabilities of MOF assessed in models with Hb levels included and not included ranged from 1.2 to 0.7 at the 10th and 90th percentile of Hb, respectively.

CONCLUSION

Anemia and decreasing levels of Hb are associated with lower cortical BMD and incident fracture in older women. Considering Hb levels may improve the clinical evaluation of patients with osteoporosis and the assessment of fracture risk.

Study of the link between hemotopoietic and skeletal systems in patients attending a referral center for osteoporosis

PURPOSE

To investigate the link between hematopoietic and skeletal tissues in patients with fragility fractures.

METHODS

We retrospectively analyzed the medical records of women older than 40 years who attended the Bone Disease Unit of "Sapienza" University of Rome for their first visit for osteoporosis from January 2020 to June 2022.

RESULTS

Fragility fractures were found in 61.8% of the sample. In particular, vertebral fractures in 35.5%, femoral fractures in 6.3%, Colles fractures in 16.5% and non-vertebral non-hip in 42.5%. Fractured patients were significantly older compared to non-fractured, had lower mean values of lumbar spine (p = 0.01), and femoral neck BMD (p = 0.007). A red blood cell distribution width (RDW) value higher than 15% was observed four times more in those with fractures compared to non-fractured patients (8.9% vs 2%, p = 0.01) and was associated with vertebral fracture after adjusting for age, BMI, menopause, nutritional status, smoking, osteoporosis and anemia (OR = 4.1, 95% CI 1.6-11.4, p = 0.003). Hematocrit was negatively associated with hip fracture also adjusting for age, BMI, menopause, nutritional status, smoking, osteoporosis (p = 0.025).

CONCLUSION

Our study demonstrates that RDW values were significantly associated with vertebral fracture and hematocrit with hip fracture. Since both parameters are included in the initial evaluation of patients with suspected bone fragility, our results should push doctors to look at these values with no incremental cost for national health services.

The Pathophysiology, Identification and Management of Fracture Risk, Sublesional Osteoporosis and Fracture among Adults with Spinal Cord Injury

BACKGROUND

The prevention of lower extremity fractures and fracture-related morbidity and mortality is a critical component of health services for adults living with chronic spinal cord injury (SCI).

METHODS

Established best practices and guideline recommendations are articulated in recent international consensus documents from the International Society of Clinical Densitometry, the Paralyzed Veterans of America Consortium for Spinal Cord Medicine and the Orthopedic Trauma Association.

RESULTS

This review is a synthesis of the aforementioned consensus documents, which highlight the pathophysiology of lower extremity bone mineral density (BMD) decline after acute SCI. The role and actions treating clinicians should take to screen, diagnose and initiate the appropriate treatment of established low bone mass/osteoporosis of the hip, distal femur or proximal tibia regions associated with moderate or high fracture risk or diagnose and manage a lower extremity fracture among adults with chronic SCI are articulated. Guidance regarding the prescription of dietary calcium, vitamin D supplements, rehabilitation interventions (passive standing, functional electrical stimulation (FES) or neuromuscular electrical stimulation (NMES)) to modify bone mass and/or anti-resorptive drug therapy (Alendronate, Denosumab, or Zoledronic Acid) is provided. In the event of lower extremity fracture, the need for timely orthopedic consultation for fracture diagnosis and interprofessional care following definitive fracture management to prevent health complications (venous thromboembolism, pressure injury, and autonomic dysreflexia) and rehabilitation interventions to return the individual to his/her pre-fracture functional abilities is emphasized.

CONCLUSIONS

Interprofessional care teams should use recent consensus publications to drive sustained practice change to mitigate fracture incidence and fracture-related morbidity and mortality among adults with chronic SCI.

Correlation of hemoglobin with osteoporosis in elderly Chinese population: A cross-sectional study

Introduction

In the elder population, both low hemoglobin (Hb)/anemia and osteoporosis (OP) are highly prevalent. However, the relationship between Hb and OP is still poorly understood. This study was to evaluate the correlation between Hb and OP in Chinese elderly population.

Methods

One thousand and sisty-eight individuals aged 55-85 years were enrolled into this cross-sectional study during June 2019-November 2019. Data on the demographics and clinical characteristics were recorded. Detections of complete blood count, liver/kidney function, glucose metabolism and lipid profile, and thoracolumbar X-ray were performed, and bone mineral density (BMD) at lumbar spine 1-4, femur neck, and total hip was measured by dual-energy X-ray absorptiometry (DXA). Univariate and multivariate linear regression analyses were employed to evaluate the correlation between Hb with BMD T-score. Logistic regression analysis was performed to access the correlation between different Hb levels and the odds ratio (OR) for OP.

Results

Compared with non-OP group, OP patients had lower level of Hb. Univariate linear regression analysis indicated Hb level was positively related to the BMD of lumbar spine 1-4, femur neck and total hip, and this relationship remained after adjusting confounding variables [gender, age, body mass index (BMI), diabetes mellitus (DM) and morphological vertebral fracture]. Logistic regression analysis showed the ORs for OP decreased with the increase of Hb. Compared with the subjects with the lowest quartile of Hb, the OR for OP in the highest quartile group was 0.60 (0.41-0.89) after adjusting for gender, age and BMI, and the OR for OP was 0.62 (0.41-0.92) after further adjustment for gender, age, BMI, DM, and lipid indexes.

Discussion

In conclusion, Lower Hb level is related to lower BMD in the elderly population. However, whether Hb level could be used to predict the risk of OP needs to be further determined in more longitudinal clinical studies.

Osteoblast Lineage Support of Hematopoiesis in Health and Disease

In mammals, hematopoiesis migrates to the bone marrow during embryogenesis coincident with the appearance of mineralized bone, where hematopoietic stem cells (HSCs) and their progeny are maintained by the surrounding microenvironment or niche, and sustain the entirety of the hematopoietic system. Genetic manipulation of niche factors and advances in cell lineage tracing techniques have implicated cells of both hematopoietic and nonhematopoietic origin as important regulators of hematopoiesis in health and disease. Among them, cells of the osteoblast lineage, from stromal skeletal stem cells to matrix-embedded osteocytes, are vital niche residents with varying capacities for hematopoietic support depending on stage of differentiation. Here, we review populations of osteoblasts at differing stages of differentiation and summarize the current understanding of the role of the osteoblast lineage in supporting hematopoiesis. © 2022 American Society for Bone and Mineral Research (ASBMR).

Anemia is associated with increased risk of non-vertebral osteoporotic fractures in elderly men: the MrOS Sweden cohort

This study includes 1005 men from the Gothenburg part of the Osteoporotic Fracture in Men Study (MrOS). Included are 66 men with anemia (hemoglobin < 130 g/L). The follow-up time was up to 16 years, and the main results are that anemia is associated with all fractures and non-vertebral osteoporotic fractures.

INTRODUCTION

Anemia and osteoporotic fractures are conditions that are associated with increased morbidity and mortality. Clinical studies have suggested that anemia can be used as a predictor of future osteoporotic fractures.

METHOD

Men from the Osteoporotic Fractures in Men Study (MrOS) Sweden, Gothenburg, with available hemoglobin (Hb) values (n = 1005, median age 75.3 years (SD 3.2)), were included in the current analyses. Of these, 66 suffered from anemia, defined as Hb < 130 g/L. Median follow-up time for fracture was 10.1 years and the longest follow-up time was 16.1 years.

RESULTS

Men with anemia had, at baseline, experienced more falls and had a higher prevalence of diabetes, cancer, prostate cancer, hypertension, and stroke. Anemia was not statistically significantly associated with bone mineral density (BMD). Men with anemia had higher serum levels of fibroblast growth factor 23 (iFGF23) (p < 0.001) and phosphate (p = 0.001) and lower serum levels of testosterone (p < 0.001) and estradiol (p < 0.001). Moreover, men with anemia had an increased risk of any fracture (hazard ratio (HR) 1.97, 95% CI 1.28-3.02) and non-vertebral osteoporotic fracture (HR 2.15, 95% CI 1.18-3.93), after adjustment for age and total hip BMD, in 10 years. The risk for any fracture was increased in 10 and 16 years independently of falls, comorbidities, inflammation, and sex hormones. The age-adjusted risk of hip fracture was increased in men with anemia (HR 2.32, 95% CI 1.06-5.12), in 10 years, although this was no longer statistically significant after further adjustment for total hip BMD.

CONCLUSIONS

Anemia is associated with an increased risk for any fracture and non-vertebral osteoporotic fracture in elderly men with a long follow-up time. The cause is probably multifactorial and our results support that anemia can be used as a predictor for future fracture.

[Assessment of the prevalence of anemia in patients with primary hyperparathyroidism: a single-center observational study]

BACKGROUND

The combination of primary hyperparathyroidism (PHPT) with anemia was first described in 1931. It remains unclear whether PHPT is the direct cause of anemia, or it develops due to PHPT's complications. The frequency of PHPT--associated anemia in the Russian population is unknown.

AIM

To assess the prevalence of anemia in patients with PHPT admitted to the Department of Parathyroid Glands Pathology in the Endocrinology Research Centre from January 2017 to August 2020.

MATERIALS AND METHODS

The study included patients with PHPT over 18 years old. A single-center observational one-stage one-sample uncontrolled study was carried out. We analyzed laboratory and instrumental data obtained during inpatient examination in accordance with the standards of medical care. Statistical analysis was performed using Statistica 13 (StatSoft, USA) and SPSS (IBM, USA) software packages.

RESULTS

The study included 327 patients with PHPT, 28 (9%) men and 299 (91%) women. The median age was 59 years [51; 66]. 26 patients (8%) with anemia were identified. Statistically significant differences between patients with and without anemia were found only in the GFR. Comparison of patients with and without anemia didn't reveal any significant differences in the incidence of PHPT's complications.Significant differences in serum hemoglobin concentration and average hemoglobin concentration in erythrocytes were revealed between patients with and without vertebrae fractures. In the group of patients without compression fractures these parameters were higher.In the subgroup of patients with total calcium concentration above 3 mmol/L and PTH above 3 normal values, the incidence of anemia reached 21% (95% CI: 10%; 35%). Within this group we revealed tendencies to higher levels of PTH, ionized calcium and osteocalcin in patients with anemia.

CONCLUSION

In general, there was no correlation between hypercalcemia, the degree of PTH elevation and the presence of anemia in patients with PHPT. However, in the subgroup of patients with severe hypercalcemia, there was a relationship between the concentration of PTH, ionized calcium and the presence of anemia. In patients with PHPT and vertebral fractures, significantly lower concentrations of blood hemoglobin and hemoglobin in erythrocytes were observed.

Association of hemoglobin level with fracture: a nationwide cohort study

INTRODUCTION

The association between hemoglobin (Hb) level including anemia and fracture has not been studied thoroughly.

MATERIALS AND METHODS

197, 187 adults ≥ 50 years from the National Health Insurance Service of Korea were studied. Hb was determined during health screening examinations in 2004 or 2005. From 1 January 2006, participants were followed up for fracture until 31 December 2013. Hb levels (g/dL) were categorized into five groups, with normal hemoglobin levels subdivided into three groups (low normal, normal, and high normal Hb): < 13, ≥ 13 to < 14, ≥ 14 to < 16, ≥ 16 to < 17, 17 for men and < 12, ≥ 12 to < 13, ≥ 13 to < 14, ≥ 14 to < 16, ≥ 16 for women. Anemia was defined as Hb < 13 g/dL and < 12 g/dL for men and women, respectively. Cox proportional hazards regression was used to determine the adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs) for fracture according to Hb.

RESULTS

Compared to individuals with normal Hb, those with anemia and low normal Hb were associated with significantly increased risk of fracture. In women, those with anemia had a higher risk for any (aHR 1.11, 95% CI 1.05-1.17), hip (aHR 1.27, 95% CI 1.01-1.59), and radius fracture (aHR 1.15, 95% CI 1.05-1.25). In men, those with anemia had a higher risk for any (aHR 1.37, 95% CI 1.23-1.51), vertebral (aHR 1.33, 95% CI 1.15-1.53), and hip fracture (aHR 1.64, 95% CI 1.30-2.08). This risk-enhancing association was preserved among various subgroups.

CONCLUSION

Among adults ≥ 50 years, anemia and low normal Hb are risk factors for fracture.

Associations of hemoglobin and change in hemoglobin with risk of incident hip fracture in older men and women: the cardiovascular health study

In a multi-site longitudinal cohort study, decreasing hemoglobin was associated with increased hip fracture risk in men. Anemia was associated with hip fracture in men and in African American women. Decreasing hemoglobin may be a marker of progressing bone fragility, making its serial measurement useful for fracture risk stratification.

INTRODUCTION

Hematopoiesis and bone health are interdependent. Anemia has been associated with risk of fracture in humans. To further elucidate this relationship, we hypothesized that decreasing hemoglobin could indicate defective hematopoiesis and would also predict fracture risk.

METHODS

We performed a prospective analysis from study baseline (1992) of the Cardiovascular Health Study, a multi-site longitudinal cohort study. A total of 4670 men and women, ages >65 years, who were able to consent and not institutionalized or wheelchair bound, had hemoglobin (Hb) measured in 1992. For 4006 subjects, Hb change from 1989 to 1992 was annualized and divided into sex-specific quartiles. Incident hip fractures were verified against Medicare claims data during a median follow-up of 11.8 years.

RESULTS

Nested Cox proportional-hazard models estimated association of hip fracture with anemia (men Hb <13 g/dL, women Hb <12 g/dL) and separately, greatest Hb decrease (versus others). Anemia was associated with increased hip fracture risk in all men (HR 1.59; 95% CI 1.01-2.50) and African American women (HR 3.21; 95% CI 1.07-9.63). In men, an annualized Hb loss of >0.36 g/dL/year was associated with a higher risk of hip fracture (HR 1.67; 95% CI 1.10-2.54), which was lessened by anemia at the start of fracture follow-up (HR 1.53; 95% CI 0.99-2.39).

CONCLUSIONS

Decreasing Hb may be an early marker for subsequent hip fracture risk in men, which may be less informative once an anemia threshold is crossed. Only African American women with anemia had increased hip fracture risk, suggesting a race difference in this relationship.

Erythropoietin in bone homeostasis-Implications for efficacious anemia therapy

Bone homeostasis and hematopoiesis are irrevocably linked in the hypoxic environment of the bone marrow. Erythropoietin (Epo) regulates erythropoiesis by binding to its receptor, Epor, on erythroid progenitor cells. The continuous process of bone remodeling is achieved by the finely balanced activity of osteoblasts in bone synthesis and osteoclasts in bone resorption. Both osteoblasts and osteoclasts express functional Epors, but the underlying mechanism of Epo‐Epor signaling in bone homeostasis is incompletely understood. Two recent publications have provided new insights into the contribution of endogenous Epo to bone homeostasis. Suresh et al examined Epo‐Epor signaling in osteoblasts in bone formation in mice and Deshet‐Unger et al investigated osteoclastogenesis arising from transdifferentiation of B cells. Both groups also studied bone loss in mice caused by exogenous human recombinant EPO‐stimulated erythropoiesis. They found that either deletion of Epor in osteoblasts or conditional knockdown of Epor in B cells attenuates EPO‐driven bone loss. These findings have direct clinical implications because patients on long‐term treatment for anemia may have an increased risk of bone fractures. Phase 3 trials of small molecule inhibitors of the PHD enzymes (hypoxia inducible factor‐prolyl hydroxylase inhibitors [HIF‐PHIs]), such as Roxadustat, have shown improved iron metabolism and increased circulating Epo levels in a titratable manner, avoiding the supraphysiologic increases that often accompany intravenous EPO therapy. The new evidence presented by Suresh and Deshet‐Unger and their colleagues on the effects of EPO‐stimulated erythropoiesis on bone homeostasis seems likely to stimulate discussion on the relative merits and safety of EPO and HIF‐PHIs.

Helicobacter pylori Related Diseases and Osteoporotic Fractures (Narrative Review)

Osteoporosis (OP) and osteoporotic fractures (OFs) are common multifactorial and heterogenic disorders of increasing incidence. Helicobacter pylori (H.p.) colonizes the stomach approximately in half of the world's population, causes gastroduodenal diseases and is prevalent in numerous extra-digestive diseases known to be associated with OP/OF. The studies regarding relationship between H.p. infection (HPI) and OP/OFs are inconsistent. The current review summarizes the relevant literature on the potential role of HPI in OP, falls and OFs and highlights the reasons for controversies in the publications. In the first section, after a brief overview of HPI biological features, we analyze the studies evaluating the association of HPI and bone status. The second part includes data on the prevalence of OP/OFs in HPI-induced gastroduodenal diseases (peptic ulcer, chronic/atrophic gastritis and cancer) and the effects of acid-suppressive drugs. In the next section, we discuss the possible contribution of HPI-associated extra-digestive diseases and medications to OP/OF, focusing on conditions affecting both bone homeostasis and predisposing to falls. In the last section, we describe clinical implications of accumulated data on HPI as a co-factor of OP/OF and present a feasible five-step algorithm for OP/OF risk assessment and management in regard to HPI, emphasizing the importance of an integrative (but differentiated) holistic approach. Increased awareness about the consequences of HPI linked to OP/OF can aid early detection and management. Further research on the HPI-OP/OF relationship is needed to close current knowledge gaps and improve clinical management of both OP/OF and HPI-related disorders.

Comparison of clinical risk factors for incident fracture in obese and non-obese community-dwelling older men

BACKGROUND

Obese older adults have higher bone mineral density (BMD), but other characteristics of obesity may predispose these individuals to fracture. We aimed to compare clinical risk factors for incident fracture in obese and non-obese older men.

METHODS

Body mass index (BMI) and body fat percentage were assessed at baseline by anthropometry and dual-energy X-ray absorptiometry, respectively, in 1625 community-dwelling men aged ≥70 years. Categories for non-obese and obese were <30 kg/m²and ≥30 kg/m² for BMI, and <30% and ≥30% for body fat percentage. Sociodemographic, medical, physical function and blood biochemistry parameters were collected at baseline. Self-reported incident fractures of any type and cause (excluding pathological fractures and fractures of hands, fingers, feet, toes and the skull) were confirmed by radiographic reports and recorded up to 9 years. Hip fractures were followed for 14 years using data linkage.

RESULTS

Prevalence of obesity was 27% according to BMI and 44% according to body fat percentage. There were no differences in incidence of any fracture between non-obese and obese men by BMI (10.7 vs 9.3%, respectively; P > 0.05) or body fat percentage (10.2 vs 10.6%, respectively; P > 0.05). Significant interactions were observed demonstrating that dementia increased hazard for incident any and hip fracture in non-obese men (adjusted hazard ratio 7.08; 95% CI 3.27-15.36 and 8.36; 3.13-22.31, respectively) but not obese men. Past-year falls increased hazard for any fracture in obese men (2.86; 95% CI 1.60-5.10) but not non-obese men while higher luteinizing hormone concentrations reduced hazard for hip fracture in obese men (0.91; 0.85-0.97 per IU/L) but not non-obese men.

CONCLUSIONS

In community-dwelling older men, obesity does not protect against incident fracture. Assessments of falls history and gonadotrophin levels, in addition to established clinical risk factors for fracture, may contribute to improvements in fracture prediction in obese older men.

The Analysis for Anemia Increasing Fracture Risk

Background

Fractures are a major public health problem for elderly people throughout the world. Anemia is also a common, important health problem among elderly populations. The aim of this article was to estimate the association between anemia and fracture incidence via a systematic review and meta-analysis.

Material/Methods

The participant, intervention, observation, and study design (PICOS) reporting guidelines were followed, and databases were searched from their inception to May 2020 to identify relevant studies. When heterogeneity was significant, and a random-effects model was used. Subgroup analysis was conducted to explore the source of heterogeneity based on sex, study design, and region.

Result

We found that anemia significantly increased fracture risk [relative risk (RR)=1.26, 95% confidence interval (CI)=1.14–1.39, P<0.001], specifically, hip fracture (RR=1.44, 95% CI=1.29–1.61), spine fracture (RR=1.15, 95% CI=1.08–1.23), and nonspine fracture (RR=1.42, 95% CI=1.33–1.52). Males with anemia had a 1.51-fold higher fracture risk, females had a 1.09-fold higher fracture risk. And the association was stronger in Asian (RR=1.22, 95% CI=1.07–1.40), but not in American and European study populations.

Conclusions

In conclusion, a significantly increased fracture risk was observed, and anemia can be a predictor of fracture risk.

Red Cell Distribution Width Is a Risk Factor for Hip Fracture in Elderly Men Without Anemia

Red cell distribution width (RDW), routinely assessed as a component of a complete blood count (CBC), quantifies the variation in the size of red blood cells. It increases with age, and increased RDW predicts many aging-related diseases and mortality. However, whether it also predicts hip fracture is unknown. We prospectively evaluated the association between RDW and hip fracture using data from the Osteoporotic Fracture in Men (MrOS) study. RDW was measured in 3635 men (aged 71 to 99 years) along with bone mineral density (BMD) in MrOS. RDW ranged from 11.3% to 32.9% (median 14.0%; interquartile range 13.5% to 14.8%) and was categorized into four groups (≤13.0%, 13.1% to 14.0%, 14.1% to 15.0%, ≥15.1%). Study participants with a hemoglobin level <13.0 g/dL were classified as having anemia. During an average 8.1 years, 164 men suffered hip fractures. The risks of hip fractures increased with increase of RDW category. Furthermore, there was a significant interaction between anemia and RDW: An association between RDW and hip fractures was only observed in participants without anemia. In those without anemia, the relative hazard of hip fractures increased with increases in RDW category: Men in the highest RDW category had a 2.8 times higher risk of hip fractures than men in the lowest group (95% confidence interval 1.1 to 7.1). The risks of all-clinical fractures were also increased along with higher RDW values. Additionally, RDW was significantly associated with the risk of having a fall but not with femoral neck or total hip BMD. In conclusion, RDW and anemia defined by hemoglobin are widely available routine laboratory measurements that together could indicate increased risk of hip fracture, reflecting the neuromuscular effects of aging rather than lower hip BMD. © 2020 American Society for Bone and Mineral Research.

The Women's Health Initiative: A Landmark Resource for Skeletal Research Since 1992

The Women's Health Initiative (WHI) is a large longitudinal study designed to investigate strategies for the prevention and control of common chronic diseases in postmenopausal women, including cardiovascular disease, cancer, and osteoporotic fractures. The WHI consisted of three overlapping clinical trials of hormone therapy, diet modification to reduce total dietary fat, and calcium/vitamin D supplementation. Women who were ineligible for the hormone therapy or diet modification trials or not interested were invited to participate in the observational study. Women were recruited into WHI from 1993 to 1998 at 40 US clinical centers. WHI enrolled 26,046 underrepresented minority women and 135,762 white women. Women could participate in each trial if eligible. The final enrollment included 27,347 women in the hormone trial; 48,835 women in the diet modification trial; 36,282 women in the calcium/vitamin D trial, and 93,676 in the observational study. After the main study ended in 2005, women were invited to continue follow-up for exposures and outcomes through two extensions to 2020. Proposals were recently submitted to continue follow-up through 2027. Information was collected on an extensive number of risk factors for fractures at baseline and over the follow-up, including fall and fracture history, weight patterns, comorbidities, diet, reproductive history, medications, anthropometry, and biomarkers. Bone mineral density was measured at three WHI clinical centers (n = 11,020) chosen to maximize race/ethnic diversity. WHI encourages outside investigators to make use of the publicly available WHI data and to access the biobank of specimens (www.whi.org). © 2020 American Society for Bone and Mineral Research.

High Plasma Erythropoietin Predicts Incident Fractures in Elderly Men with Normal Renal Function: The MrOS Sweden Cohort

Preclinical studies on the role of erythropoietin (EPO) in bone metabolism are contradictory. Regeneration models indicate an anabolic effect on bone healing, whereas models on physiologic bone remodeling indicate a catabolic effect on bone mass. No human studies on EPO and fracture risk are available. It is known that fibroblast growth factor 23 (FGF23) affects bone mineralization and that serum concentration of FGF23 is higher in men with decreased estimated glomerular filtration rate (eGFR). Recently, a direct association between EPO and FGF23 has been shown. We have explored the potential association between EPO and bone mineral density (BMD), fracture risk, and FGF23 in humans. Plasma levels of EPO were analyzed in 999 men (aged 69 to 81 years), participating in the Gothenburg part of the population-based Osteoporotic Fractures in Men (MrOS) study, MrOS Sweden. The mean ± SD EPO was 11.5 ± 9.0 IU/L. Results were stratified by eGFR 60 mL/min. For men with eGFR ≥60 mL/min (n = 728), EPO was associated with age (r = 0.13, p < 0.001), total hip BMD (r = 0.14, p < 0.001), intact (i)FGF23 (r = 0.11, p = 0.004), and osteocalcin (r = -0.09, p = 0.022). The association between total hip BMD and EPO was independent of age, body mass index (BMI), iFGF23, and hemoglobin (beta = 0.019, p < 0.001). During the 10-year follow-up, 164 men had an X-ray-verified fracture, including 117 major osteoporotic fractures (MOF), 39 hip fractures, and 64 vertebral fractures. High EPO was associated with higher risk for incident fractures (hazard ratio [HR] = 1.43 per tertile EPO, 95% confidence interval [CI] 1.35-1.63), MOF (HR = 1.40 per tertile EPO, 95% CI 1.08-1.82), and vertebral fractures (HR = 1.42 per tertile EPO, 95% CI 1.00-2.01) in a fully adjusted Cox regression model. In men with eGFR<60 mL/min, no association was found between EPO and BMD or fracture risk. We here demonstrate that high levels of EPO are associated with increased fracture risk and increased BMD in elderly men with normal renal function. © 2019 American Society for Bone and Mineral Research.

Anemia and Risk of Fractures in Older Korean Adults: A Nationwide Population-Based Study

Anemia is a common health problem in older adults and is associated with risk factors for fracture such as low physical function and low bone mass. The aim of this study was to examine the relationship between anemia and fracture risk in older adults. We conducted a retrospective cohort study from 2003 to 2013. The participants were community-dwelling Korean adults aged 65 years and older who participated in the National Health Screening Program (n = 72,131) between 2003 and 2008. Anemia (<12 g/dL for women and <13 g/dL for men) and severity of anemia (mild: 11 g/dL ≤ Hb < 12 g/dL; moderate to severe: Hb < 11 g/dL) were defined by World Health Organization (WHO) criteria. The incidence of any fractures, vertebral fractures, and femur fractures was identified using ICD-10 codes. Cox proportional hazard regression models were used to assess risk of fracture according to anemia. Anemia was associated with increased risk of fracture in men (any: adjusted hazard ratio [aHR] = 1.29, 95% confidence interval [CI] 1.18-1.41; vertebral: aHR = 1.20, 95% CI 1.03-1.40; femur: aHR = 1.71, 95% CI 1.44-2.04), and less strongly but still significantly in women (any: aHR = 1.10, 95% CI 1.11-1.41; vertebral: aHR = 1.11, 95% CI 1.03-1.20; femur: aHR = 1.37, 95% CI 1.25-1.52). Higher risk was observed in subjects with moderate-to-severe anemia in both sexes. Considering the high prevalence of anemia in older adults, it is important that health professionals recognize increased fracture risk in older adults with anemia. © 2019 American Society for Bone and Mineral Research.

Association of bone mineral density with hemoglobin and change in hemoglobin among older men and women: The Cardiovascular Health Study

PURPOSE

Osteoblasts and their precursors support hematopoiesis in the bone marrow. We hypothesized that declines in Hgb levels are associated with bone mineral density (BMD).

METHODS

The Cardiovascular Health Study is a prospective longitudinal study that enrolled 5888 community-dwelling adults aged >65 years and measured hemoglobin twice, in 1989-90 and 1992-93, as well as BMD by dual-energy X-ray absorptiometry (DXA) in 1994-95. In a subset of 1513 men and women with a Hgb in 1992-93 and BMD, we used linear regression to estimate associations of Hgb (per standard deviation (SD)) with total hip (TH), lumbar spine (LS) and total body (TB) BMD, and used Poisson regression to estimate associations of anemia (in 1992-93; Hgb <13 g/dL in men; <12 g/dL in women) with "low BMD" defined as T-score less than -1 at the TH. In 1277 participants with Hgb measured on average 2.9 years apart and BMD, we used linear regression to estimate the associations of annualized change in Hgb with TH, LS and TB BMD. All models included age, sex, study-site, race, smoking, alcohol use, weight, height, steroid use, physical activity score, self-reported health, previous cardiovascular disease and prior anti-fracture medication use.

RESULTS

No significant association was observed between Hgb, measured a mean 2.2 years prior to BMD, and BMD at the TH and LS in men (TH beta = -0.60 [x 10^-2 g/cm²per 1.1 g/dL Hgb], 95% CI: -1.88 to 0.68; LS beta = -1.69, 95% CI: -3.83 to 0.45) or women (TH beta = -0.49 [x 10^-2 g/cm²per 1.3 g/dL Hgb], 95% CI: -1.57 to 0.59; LS beta = -0.40, 95% CI: -2.57 to 1.76). Anemia was not observed to be significantly associated with low BMD in men (RR = 0.99, 95% CI: 0.72-1.40) nor women (RR = 0.98, 95% CI: 0.82-1.17). The mean change in Hgb was a loss of 0.06 g/dL/year (SD = 0.32). Change in Hgb was not observed to be significantly associated with BMD in men (TH beta = -0.55[x 10^-2 g/cm²per 1 g/dL annualized Hgb change], 95% CI: -4.28 to 3.19; LS beta = 0.63, 95% CI: -5.38 to 6.65) or women (TH beta = 0.92, 95% CI: -1.96 to 3.79; LS beta = -1.77, 95% CI: -7.52 to 3.98). No significant association was observed between anemia and low bone density by T-score in men and women.

CONCLUSIONS

These findings support neither the hypothesis that low Hgb prior to bone density or decreases in Hgb are associated with bone density in older community-dwelling adults nor the use of Hgb level as a case-finding tool to prompt BMD measurement.

Erythropoiesis, EPO, macrophages, and bone

The regulation of erythropoiesis in the bone marrow microenvironment is a carefully orchestrated process that is dependent upon both systemic and local cues. Systemic erythropoietin (EPO) production by renal interstitial cells plays a critical role in maintaining erythropoietic homeostasis. In addition, there is increasing clinical and preclinical data linking changes in EPO and erythropoiesis to altered skeletal homeostasis, suggesting a functional relationship between the regulation of erythropoiesis and bone homeostasis. As key local components of the bone marrow microenvironment and erythropoietic niche, macrophage subsets play important roles in both processes. In this review, we summarize our current understanding of the cellular and molecular mechanisms that may facilitate the coordinated regulation of erythropoiesis and bone homeostasis.

Bone and blood interactions in human health and disease

Under physiologic conditions hematopoiesis takes place in the bone marrow, and the skeleton provides the structural and supportive network necessary for normal hematopoiesis. Chronic disorders affecting hematopoiesis such as sickle cell anemia and thalassemia demonstrate striking skeletal phenotypes including bone loss and increased fracture risk. There is mounting evidence that anemia in older populations may also be associated with bone fragility. Given the interconnectedness of bone and hematopoietic cells, it is important to review the potential clinical implications and opportunities for therapeutic intervention. There are recognized associations between blood-borne and solid tissue malignancy and skeletal health, but our review will focus on non-malignant disease.

Elevated Red Blood Cell Distribution Width Is Associated with Morphometric Vertebral Fracture in Community-Dwelling Older Adults, Independent of Anemia, Inflammation, and Nutritional Status: The Korean Urban Rural Elderly (KURE) Study

Elevated red blood cell distribution width (RDW), a simple measure of red blood cell size heterogeneity, has been associated with increased mortality and morbidity in the elderly population, which might reflect systemic inflammation and malnutrition. However, whether elevated RDW is associated with prevalent morphometric vertebral fracture (VF) in older adults has not been investigated. We examined 2127 individuals (mean age 71.7 years; women 66%) from a community-based cohort. VF was defined as ≥ 25% reduction in vertebral column height using the Genant semiquantitative method. Multiple VF was defined as the presence of VF at two or more sites. The prevalence of any VF and multiple VF was 14% and 4%, respectively, increasing from the lowest to the highest RDW tertiles (12-18% and 3-6%, p for trend < 0.05 for all). RDW was positively associated with age, body mass index (BMI), malnutrition, and high-sensitivity C-reactive protein (hsCRP), whereas it was negatively associated with albumin, hemoglobin, and ferritin levels. Elevated RDW was associated with any VF [adjusted odds ratio (aOR) 1.26; p = 0.008] and multiple VF (aOR 1.36; p = 0.010) after adjustment for covariates, including age, sex, BMI, hsCRP, malnutrition, self-reported previous fracture, falls, osteoporosis, and hemoglobin and ferritin levels. The association between elevated RDW and VF remained robust in subgroups with (aOR 1.39; p = 0.048) or without anemia (aOR 1.26; p = 0.030). Elevated RDW was associated with prevalent morphometric VF in community-dwelling elderly individuals, independent of anemia, inflammation, and nutritional status.

Bone Turnover Status: Classification Model and Clinical Implications

Aim: To develop a practical model for classification bone turnover status and evaluate its clinical usefulness. Methods: Our classification of bone turnover status is based on internationally recommended biomarkers of both bone formation (N-terminal propeptide of type1 procollagen, P1NP) and bone resorption (beta C-terminal cross-linked telopeptide of type I collagen, bCTX), using the cutoffs proposed as therapeutic targets. The relationships between turnover subtypes and clinical characteristic were assessed in1223 hospitalised orthogeriatric patients (846 women, 377 men; mean age 78.1±9.50 years): 451(36.9%) subjects with hip fracture (HF), 396(32.4%) with other non-vertebral (non-HF) fractures (HF) and 376 (30.7%) patients without fractures. Resalts: Six subtypes of bone turnover status were identified: 1 - normal turnover (P1NP>32 μg/L, bCTX≤0.250 μg/L and P1NP/bCTX>100.0[(median value]); 2- low bone formation (P1NP ≤32 μg/L), normal bone resorption (bCTX≤0.250 μg/L) and P1NP/bCTX>100.0 (subtype2A) or P1NP/bCTX<100.0 (subtype 2B); 3- low bone formation, high bone resorption (bCTX>0.250 μg/L) and P1NP/bCTX<100.0; 4- high bone turnover (both markers elevated ) and P1NP/bCTX>100.0 (subtype 4A) or P1NP/bCTX<100.0 (subtype 4B). Compared to subtypes 1 and 2A, subtype 2B was strongly associated with nonvertebral fractures (odds ratio [OR] 2.0), especially HF (OR 3.2), age>75 years and hyperparathyroidism. Hypoalbuminaemia and not using osteoporotic therapy were two independent indicators common for subtypes 3, 4A and 4B; these three subtypes were associated with in-hospital mortality. Subtype 3 was associated with fractures (OR 1.7, for HF OR 2.4), age>75 years, chronic heart failure (CHF), anaemia, and history of malignancy, and predicted post-operative myocardial injury, high inflammatory response and length of hospital stay (LOS) above10 days. Subtype 4A was associated with chronic kidney disease (CKD), anaemia, history of malignancy and walking aids use and predicted LOS>20 days, but was not discriminative for fractures. Subtype 4B was associated with fractures (OR 2.1, for HF OR 2.5), age>75 years, CKD and indicated risks of myocardial injury, high inflammatory response and LOS>10 days. Conclusions: We proposed a classification model of bone turnover status and demonstrated that in orthogeriatric patients altered subtypes are closely related to presence of nonvertebral fractures, comorbidities and poorer in-hospital outcomes. However, further research is needed to establish optimal cut points of various biomarkers and improve the classification model.

Older Men With Anemia Have Increased Fracture Risk Independent of Bone Mineral Density

CONTEXT

Extremely low hemoglobin (Hgb) values have been linked to increased fracture risk at different sites. However, careful assessment of clinically defined anemia and fracture risk is lacking.

OBJECTIVE

To determine whether men with anemia were at increased risk of fracture after accounting for bone mineral density (BMD) and bone loss.

DESIGN

Cross-sectional analysis (at visit 3) and prospective analysis (from baseline to visit 3) in the Osteoporotic Fractures in Men (MrOS), a multisite, longitudinal cohort study.

SETTING

Six communities in the United States.

PARTICIPANTS

A total of 3632 community-dwelling men (age ≥65 years) in MrOS at baseline (2000 through 2002) who were able to walk unassisted, did not have hip replacement or fracture, and had complete blood cell counts at visit 3 (2007 through 2009).

OUTCOMES

Adjudicated spine and nonspine fractures during a median 7.2 years of follow-up.

RESULTS

Analytic baseline characteristics associated with fractures or anemia (defined as Hgb <12 g/dL) were included in multivariable models. Anemia was associated with increased risk of any fracture [hazard ratio (HR), 1.67; 95% confidence interval (CI), 1.26 to 2.21] and nonspine fracture (HR, 1.70; 95% CI, 1.25 to 2.31). A model including change in BMD slightly attenuated the association with any (HR, 1.60; 95% CI, 1.20 to 2.13) and nonspine fractures (HR, 1.57; 95% CI, 1.14 to 2.15). Including absolute BMD did not significantly alter the anemia-fracture association. Anemia was not associated with spine fracture.

CONCLUSIONS

Community-dwelling older men with anemia had a 57% to 72% increase in nonspine fracture risk independent of BMD and bone loss.

Fractures in indigenous compared to non-indigenous populations: A systematic review of rates and aetiology

BACKGROUND

Compared to non-indigenous populations, indigenous populations experience disproportionately greater morbidity, and a reduced life expectancy; however, conflicting data exist regarding whether a higher risk of fracture is experienced by either population. We systematically evaluate evidence for whether differences in fracture rates at any skeletal site exist between indigenous and non-indigenous populations of any age, and to identify potential risk factors that might explain these differences.

METHODS

On 31 August 2016 we conducted a comprehensive computer-aided search of peer-reviewed literature without date limits. We searched PubMed, OVID, MEDLINE, CINAHL, EMBASE, and reference lists of relevant publications. The protocol for this systematic review is registered in PROSPERO, the International Prospective Register of systematic reviews (CRD42016043215). Using the World Health Organization reference population as standard, hip fracture incidence rates were re-standardized for comparability between countries.

RESULTS

Our search yielded 3227 articles; 283 potentially eligible articles were cross-referenced against predetermined criteria, leaving 27 articles for final inclusion. Differences in hip fracture rates appeared as continent-specific, with lower rates observed for indigenous persons in all countries except for Canada and Australia where the opposite was observed. Indigenous persons consistently had higher rates of trauma-related fractures; the highest were observed in Australia where craniofacial fracture rates were 22-times greater for indigenous compared to non-indigenous women. After adjustment for socio-demographic and clinical risk factors, approximately a three-fold greater risk of osteoporotic fracture and five-fold greater risk of craniofacial fractures was observed for indigenous compared to non-indigenous persons; diabetes, substance abuse, comorbidity, lower income, locality, and fracture history were independently associated with an increased risk of fracture.

CONCLUSIONS

The observed paucity of data and suggestion of continent-specific differences indicate an urgent need for further research regarding indigenous status and fracture epidemiology and aetiology. Our findings also have implications for communities, governments and healthcare professionals to enhance the prevention of trauma-related fractures in indigenous persons, and an increased focus on modifiable lifestyle behaviours to prevent osteoporotic fractures in all populations.

Bone Density Loss Is Associated With Blood Cell Counts

Hematopoiesis depends on a supportive microenvironment. Preclinical studies in mice have demonstrated that osteoblasts influence the development of blood cells, particularly erythrocytes, B lymphocytes, and neutrophils. However, it is unknown whether osteoblast numbers or function impact blood cell counts in humans. We tested the hypothesis that men with low BMD or greater BMD loss have decreased circulating erythrocytes and lymphocytes and increased myeloid cells. We performed a cross-sectional analysis and prospective analysis in the Osteoporotic Fractures in Men (MrOS) study, a multisite longitudinal cohort study. A total of 2571 community-dwelling men (≥65 years) who were able to walk without assistance, did not have a hip replacement or fracture, and had complete blood counts (CBCs) at the third study visit were analyzed. Multivariable (MV)-adjusted logistic regression estimated odds of white blood cell (WBC) subtypes (highest and lowest quintile versus middle), and anemia (clinically defined) associated with BMD by DXA scan (at visit 3), annualized percent BMD change (baseline to visit 3), and high BMD loss (>0.5%/year, from baseline to visit 3) at the femoral neck (FN) and total hip (TH). MV-adjusted models included age, BMI, cancer history, smoking status, alcohol intake, corticosteroid use, self-reported health, thiazide use, and physical activity. At visit 3 greater TH BMD loss (per 1 SD) was associated with increased odds of anemia, high neutrophils, and low lymphocytes. Annualized BMD loss of >0.5% was associated with increased odds of anemia, high neutrophils, and low lymphocytes. Similar results were observed for FN BMD regarding anemia and lymphocytes. We conclude that community-dwelling older men with declining hip BMD over about 7 years had increased risks of anemia, lower lymphocyte count, and higher neutrophil count, consistent with preclinical studies. Bone health and hematopoiesis may have greater interdependency than previously recognized. © 2016 American Society for Bone and Mineral Research.

The Impact of Disease and Drugs on Hip Fracture Risk

We report the risks of a comprehensive range of disease and drug categories on hip fracture occurrence using a strict population-based cohort design. Participants included the source population of a Swedish county, aged ≥50 years (n = 117,494) including all incident hip fractures during 1 year (n = 477). The outcome was hospitalization for hip fracture (ICD-10 codes S72.0-S72.2) during 1 year (2009-2010). Exposures included: prevalence of (1) inpatient diseases [International Classification of Diseases (ICD) codes A00-T98 in the National Patient Register 1987-2010] and (2) prescribed drugs dispensed in 2010 or the year prior to fracture. We present age- and sex-standardized risk ratios (RRs), risk differences (RDs) and population attributable risks (PARs) of disease and drug categories in relation to hip fracture risk. All disease categories were associated with increased risk of hip fracture. Largest risk ratios and differences were for mental and behavioral disorders, diseases of the blood and previous fracture (RRs between 2.44 and 3.00; RDs (per 1000 person-years) between 5.0 and 6.9). For specific drugs, strongest associations were seen for antiparkinson (RR 2.32 [95 % CI 1.48-1.65]; RD 5.2 [1.1-9.4]) and antidepressive drugs (RR 1.90 [1.55-2.32]; RD 3.1 [2.0-4.3]). Being prescribed ≥10 drugs during 1 year incurred an increased risk of hip fracture, whereas prescription of cardiovascular drugs or ≤5 drugs did not appear to increase risk. Diseases inferring the greatest PARs included: cardiovascular diseases PAR 22 % (95 % CI 14-29) and previous injuries (PAR 21 % [95 % CI 16-25]; for specific drugs, antidepressants posed the greatest risk (PAR 16 % [95 % CI 12.0-19.3]).

Osteoporosis in chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is a lifestyle-related chronic inflammatory pulmonary disease associated with significant morbidity and mortality worldwide. COPD is associated with various comorbidities found in all stages of COPD. The comorbidities have significant impact in terms of morbidity, mortality, and economic burden in COPD. Management of comorbidities should be incorporated into the comprehensive management of COPD as this will also have an effect on the outcome in COPD patients. Various comorbidities reported in COPD include cardiovascular disease, skeletal muscle dysfunction, anemia, metabolic syndrome, and osteoporosis. Osteoporosis is a significant comorbidity in COPD patients. Various risk factors, such as tobacco smoking, systemic inflammation, vitamin D deficiency, and the use of oral or inhaled corticosteroids (ICSs) are responsible for its occurrence in patients with COPD. This review will focus on the prevalence, pathogenesis, risk factors, diagnosis, and treatment of osteoporosis in COPD patients.

Hemoglobin and hip fracture risk in older non-Hispanic white adults

SUMMARY

The relationship between hemoglobin and hip fracture was examined in older non-Hispanic white adults from the third National Health and Nutrition Examination Survey (NHANES III). Both low and high hemoglobin values were associated with increased hip fracture risk before and after adjusting for selected risk factors.

INTRODUCTION

The few studies to date that have examined the relationship between hemoglobin and fracture risk have focused on low hemoglobin values. The present study examined hip fracture risk across the hemoglobin distribution in older non-Hispanic white adults from the third National Health and Nutrition Examination Survey (NHANES III, 1988-1994).

METHODS

Hemoglobin was measured using a Coulter S-plus Jr.® (Coulter Electronics, Hialeah, FL) in 2,122 non-Hispanic whites age 65 years and older. Hip fracture cases were identified using linked Medicare and mortality records obtained through 2007. Cox proportional hazards models were used to assess the best-fitting model and to estimate the hazards ratio (HR) for hip fracture by hemoglobin decile before and after adjusting for selected confounders.

RESULTS

There were 239 hip fracture cases in the analytic sample. The best fitting model was quadratic. When compared to values in the middle of the distribution, those with hemoglobin in the lowest and highest deciles had increased hip fracture risk (HRlowest decile = 2.96, 95 % confidence interval (CI) 1.44-6.08; HRhighest decile = 2.06, 95 % CI 1.09-3.92) after adjusting for age and sex. Both HRs remained significant after adjusting for additional confounders (HRlowest decile = 2.24, 95 % CI 1.09-3.92; HRhighest decile = 2.37, 95 % CI 1.35-4.16).

CONCLUSIONS

Both low and high hemoglobin values were associated with increased hip fracture risk. The mechanism underlying the relationship is not clear, but there were some suggestions that it may differ for low versus high hemoglobin.

Multimorbidity in women with and without osteoporosis: results from a large US retrospective cohort study 2004-2009

To determine the incidence of comorbidities in women with and without osteoporosis, incidence rates per 1,000 person-years were calculated using electronic health records from an integrated healthcare system. The overall comorbidity burden and health service utilization were greater in women with osteoporosis than in the controls.

INTRODUCTION

This retrospective cohort study describes the incidence of an array of comorbidities in women with and without osteoporosis (OP).

METHODS

Using electronic health records from an integrated healthcare system, we identified 22,414 women aged 55-89 years with OP and 22,414 age-matched controls without OP. Incidence rates (IRs) per 1,000 person-years (P-Y) were calculated and 95% confidence intervals (CI) were estimated.

RESULTS

Women with OP had significantly more comorbidities, medications, hospitalizations, and outpatient visits than the controls. Most cardiac comorbidity rates were 20-25% lower in the OP cohort than in the control cohort. Hypertension had the largest rate difference; the IR was 42.0 per 1,000 P-Y (95% CI 40.2-44.0) in the OP cohort compared to 94.0 (95% CI 90.7-97.4) in the control cohort. Rates for cerebrovascular disease were similar for both cohorts at 26 per 1,000 P-Y. Bronchitis, sinusitis, and cystitis were each 55 per 1,000 P-Y in the OP cohort, whereas they ranged from 28 to 34 per 1,000 P-Y in the controls. The OP cohort had decreased incidence of ovarian, uterine, colorectal, and liver cancers and increased incidence of lung cancer, breast cancer, and multiple myeloma, compared to the non-OP cohort. Falls, depression, vision, and musculoskeletal issues were higher for the OP cohort than the controls.

CONCLUSIONS

This study demonstrates the high disease burden in women with OP. This knowledge may help guide the clinical management of this population and may aid in the interpretation of adverse events in randomized clinical trials of OP therapies.

Acute exposure to high dose γ-radiation results in transient activation of bone lining cells

The present studies investigated the cellular mechanisms for the detrimental effects of high dose whole body γ-irradiation on bone. In addition, radioadaptation and bone marrow transplantation were assessed as interventions to mitigate the skeletal complications of irradiation. Increased trabecular thickness and separation and reduced cancellous bone volume fraction, connectivity density, and trabecular number were detected in proximal tibia and lumbar vertebra 14days following γ-irradiation with 6Gy. To establish the cellular mechanism for the architectural changes, vertebrae were analyzed by histomorphometry 1, 3, and 14days following irradiation. Marrow cell density decreased within 1day (67% reduction, p<0.0001), reached a minimum value after 3days (86% reduction, p<0.0001), and partially rebounded by 14days (30% reduction, p=0.0025) following irradiation. In contrast, osteoblast-lined bone perimeter was increased by 290% (1day, p=0.04), 1230% (3days, p<0.0001), and 530% (14days, p=0.003), respectively. There was a strong association between radiation-induced marrow cell death and activation of bone lining cells to express the osteoblast phenotype (Pearson correlation -0.85, p<0.0001). An increase (p=0.004) in osteoclast-lined bone perimeter was also detected with irradiation. A priming dose of γ-radiation (0.5mGy), previously shown to reduce mortality, had minimal effect on the cellular responses to radiation and did not prevent detrimental changes in bone architecture. Bone marrow transplantation normalized marrow cell density, bone turnover, and most indices of bone architecture following irradiation. In summary, radiation-induced death of marrow cells is associated with 1) a transient increase in bone formation due, at least in part, to activation of bone lining cells, and 2) an increase in bone resorption due to increased osteoclast perimeter. Bone marrow transplantation is effective in mitigating the detrimental effects of acute exposure to high dose whole body γ-radiation on bone turnover.

Bone stiffness and failure load are related with clinical parameters in men with chronic obstructive pulmonary disease

Osteoporosis is frequently seen in patients with chronic obstructive pulmonary disease (COPD). Because research on bone structure and bone strength in COPD patients is limited, the objectives of this pilot study were as follows: (1) to compare bone structure, stiffness, and failure load, measured at the peripheral skeleton, between men with and without COPD after stratification for areal bone mineral density (aBMD); and (2) to relate clinical parameters with bone stiffness and failure load in men with COPD. We included 30 men with COPD (normal aBMD, n = 18; osteoporosis, n = 12) and 17 men without COPD (normal aBMD, n = 9; osteoporosis, n = 8). We assessed pack-years of smoking, body mass index (BMI), fat free mass index (FFMI), pulmonary function (forced expiratory volume in 1 second [FEV1 ], FEV1 /forced vital capacity [FVC], diffusion capacity for carbon monoxide [DLCO], and transfer coefficient for carbon monoxide [KCO]), and extent of emphysema. Bone structure of the distal radius and tibia was assessed by high-resolution peripheral quantitative computed tomography (HR-pQCT), and bone stiffness and failure load of the distal radius and tibia were estimated from micro finite element analysis (µFEA). After stratification for aBMD and COPD, men with osteoporosis showed abnormal bone structure (p < 0.01), lower bone stiffness (p < 0.01), and lower failure load (p < 0.01) compared with men with normal aBMD, and men with COPD had comparable bone structure, stiffness, and failure load compared with men without COPD. In men with COPD, lower FFMI was related with lower bone stiffness, and failure load of the radius and tibia and lower DLCO and KCO were related with lower bone stiffness and failure load of the tibia after normalization with respect to femoral neck aBMD. Thus, this pilot study could not detect differences in bone structure, stiffness, and failure load between men with and without COPD after stratification for aBMD. FFMI and gas transfer capacity of the lung were significantly related with bone stiffness and failure load in men with COPD after normalization with respect to femoral neck aBMD.

Osteoporosis in chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is being regarded as a heterogeneous disease with clinically significant pulmonary and extrapulmonary manifestations, such as emphysema, cardiovascular disease and osteoporosis. Osteoporosis is characterized by low bone mass and microarchitectural deterioration of bone tissue, leading to enhanced bone fragility and, consequently, an increased risk of fracture. Fractures resulting from osteoporosis might contribute to increased morbidity and mortality, particularly in COPD patients. The high prevalence of osteoporosis in COPD patients is assumed to be due to common risk factors, such as older age and tobacco smoking, and COPD-specific risk factors, such as systemic inflammation, vitamin D deficiency and the use of oral or inhaled corticosteroids. This review provides a state-of-the-art summary of the prevalence, pathophysiology, diagnosis, risk factors and treatment of osteoporosis in COPD patients. It also discusses potential mechanisms linking COPD with osteoporosis.

Using longitudinal data from the Health Survey for England to resolve discrepancies in thresholds for haemoglobin in older adults

Anaemia increases with age and is common among older people. Due to its relationship with morbidity and mortality, accurate diagnosis is important. Thresholds defining the diagnosis of anaemia have been the subject of considerable scientific debate, with both higher and lower cut-offs proposed. High haemoglobin is also a health risk in some but not all studies. Using nationally representative data of 5,329 adults aged 65 + years (Health Survey for England 1998, 2005, 2006), linked to administrative mortality data, this paper describes the relationship between haemoglobin levels and mortality, adjusted for age and other confounders. Among men, a reverse J shaped relationship was observed: relative to the modal group (140-149 g/l), those with 'mild anaemia' of 120-129 g/l haemoglobin had a 56% (95% confidence interval 24-96%) greater mortality hazard, and those with 'severe anaemia', haemoglobin <120 g/l, had an 87% (39-153%) greater hazard. At the other end of the range, those with haemoglobin ≥160 g/l had 32% (2-70%) greater mortality hazard. Haemoglobin levels in women showed a similar but smaller, non-significant pattern: hazard ratio 1·32 (0·91-1·92) for severe anaemia (<110 g/l), and 1·30 (0·95-1·79) for high haemoglobin (≥150 g/l). This research supports the use of the World Health Organization thresholds (130 g/l for men, 120 g/l for women).