BMD at multiple sites and risk of fracture of multiple types: long-term results from the Study of Osteoporotic Fractures

DXA variations and fractures after simultaneous pancreas-renal transplantation: results of a long-term follow-up

Simultaneous pancreas-kidney transplant (SPKT) has been associated with an increased risk of fracture. We prospectively evaluated the long-term effects of SPKT on bone mineral density (BMD) and fracture risk. During 1998 to 1999, 29 participants were consecutively monitored, and 18 completed the 10-year follow-up. Laboratory blood parameters, lumbar-dorsal radiography, and DEXA were determined at baseline, 1 year, and 10 years. The medical record was reviewed for peripheral fragility fractures. The BMD revealed no changes between baseline and 1 or 10 years after SPKT. Lumbar-dorsal radiography showed 0% asymptomatic vertebral fractures at baseline and after 1 year with 16.7% at 10 years. Vertebral asymptomatic fractures were correlated with acute rejection episodes (P = 0.025). During the first year, no nonvertebral fractures were identified. At the end of the follow-up, 5 nonvertebral fractures in 4 patients were reported. Dorsal and lumbar spine fractures correlated with lumbar spine t score (r = -0.591, P =0.022) and peripheral fractures with femoral neck t score (r = -0.633, P = 0.013). Patients with SPKT did not show long-term significant loss of BMD. The incidence of vertebral fractures was low and related to steroid treatment; the incidence of peripheral fractures was higher and independent of clinical or biochemical parameters.

Gender differences on osteoporosis health beliefs and related behaviors in non-academic community Chinese

Osteoporosis represents the major public health concern worldwide. The purpose of this study was to assess osteoporosis beliefs and actual performance of osteoporosis preventive behaviors in non-academic community Chinese population and to explore whether the differences exist in community females and males. A cross sectional study including 137 females and 122 males was conducted in four non-academic communities of Xi'an city during November 2012, selected by multi-stage sampling method. Self-administered questionnaire was used for data collection. The respondents' mean age was 56.06 ± 5.81 years. 35.5% of the participants had a bone mineral density test. The participants exhibit relatively low osteoporosis health beliefs. The total health belief score was 63.30 ± 8.55 and 64.13 ± 6.47 in females and males respectively. There was significant gender differences in the subscales of Perceived seriousness (p = 0.03), Perceived barriers to exercise (p = 0.004) and Perceived motivation (p = 0.01). Participants had low frequencies of preventive practices. Gender differences were revealed in current smoking and alcohol intake, soybean food intake, smoking history (p < 0.001), alcohol intake history (p = 0.001), meat or egg intake (p = 0.019). The findings from the study suggest an increased awareness of this major public health problem in non-academic Chinese and the scope for enhancing osteoporosis intervention considering the gender difference.

Pleiotropic effects of obesity on fracture risk: the Study of Women's Health Across the Nation

Some aspects of an obese body habitus may protect against fracture risk (higher bone mineral density [BMD] and greater tissue padding), while others may augment that risk (greater impact forces during a fall). To examine these competing pathways, we analyzed data from a multisite, multiethnic cohort of 1924 women, premenopausal or early perimenopausal at baseline. Obesity was defined as baseline body mass index (BMI) > 30 kg/m(2) . Composite indices of femoral neck strength relative to fall impact forces were constructed from DXA-derived bone size, BMD and body size. Incident fractures were ascertained annually during a median follow-up of 9 years. In multivariable linear regression adjusted for covariates, higher BMI was associated with higher BMD but with lower composite strength indices, suggesting that although BMD increases with greater skeletal loading, the increase is not sufficient to compensate for the increase in fall impact forces. During the follow-up, 201 women had fractures. In Cox proportional hazard analyses, obesity was associated with increased fracture hazard adjusted for BMD, consistent with greater fall impact forces in obese individuals. Adjusted for composite indices of femoral neck strength relative to fall impact forces, obesity was associated with decreased fracture hazard, consistent with a protective effect of soft tissue padding. Further adjustment for hip circumference, a surrogate marker of soft tissue padding, attenuated the obesity-fracture association. Our findings support that there are at least three major mechanisms by which obesity influences fracture risk: increased BMD in response to greater skeletal loading, increased impact forces, and greater absorption of impact forces by soft tissue padding.

Osteoporosis prediction from the mandible using cone-beam computed tomography

PURPOSE

This study aimed to evaluate the use of dental cone-beam computed tomography (CBCT) in the diagnosis of osteoporosis among menopausal and postmenopausal women by using only a CBCT viewer program.

MATERIALS AND METHODS

Thirty-eight menopausal and postmenopausal women who underwent dual-energy X-ray absorptiometry (DXA) examination for hip and lumbar vertebrae were scanned using CBCT (field of view: 13 cm×15 cm; voxel size: 0.25 mm). Slices from the body of the mandible as well as the ramus were selected and some CBCT-derived variables, such as radiographic density (RD) as gray values, were calculated as gray values. Pearson's correlation, one-way analysis of variance (ANOVA), and accuracy (sensitivity and specificity) evaluation based on linear and logistic regression were performed to choose the variable that best correlated with the lumbar and femoral neck T-scores.

RESULTS

RD of the whole bone area of the mandible was the variable that best correlated with and predicted both the femoral neck and the lumbar vertebrae T-scores; further, Pearson's correlation coefficients were 0.5/0.6 (p value=0.037/0.009). The sensitivity, specificity, and accuracy based on the logistic regression were 50%, 88.9%, and 78.4%, respectively, for the femoral neck, and 46.2%, 91.3%, and 75%, respectively, for the lumbar vertebrae.

CONCLUSION

Lumbar vertebrae and femoral neck osteoporosis can be predicted with high accuracy from the RD value of the body of the mandible by using a CBCT viewer program.

Changes in bone mineral density may predict the risk of fracture differently in older adults according to fall history

OBJECTIVES

To determine whether the association between change in bone mass density (BMD) over 4 years and risk of hip and nonvertebral fracture differs according to an individual's history of falls.

DESIGN

Population-based cohort study.

SETTING

Framingham, Massachusetts.

PARTICIPANTS

Individuals with two measures of BMD at the femoral neck (mean age 78.8; 310 male, 492 female).

MEASUREMENTS

Cox proportional hazards models were used to estimate hazard ratios (HRs) for the association between percentage change in BMD (per sex-specific standard deviation) and risk of incident hip and nonvertebral fracture. Models were stratified based on history of falls (≥1 falls in the past year) and recurrent falls (≥2 falls) ascertained at the time of the second BMD test. Interactions were tested by including the term "fall history * change in BMD" in the models.

RESULTS

Mean change in BMD was -0.6%/year; 27.8% of participants reported falls, and 10.8% reported recurrent falls. Seventy-six incident hip and 175 incident nonvertebral fractures occurred over a median follow-up of 9.0 years. There was no difference in the association between change in BMD and hip fracture according to history of falls (P for interaction = .57). The HR associated with change in BMD and nonvertebral fracture was 1.31 (95% confidence interval (CI) = 1.10-1.56) in participants without a history of falls and 0.95 (95% CI 0.70-1.28) in those with a fall (interaction P = .07). Results for recurrent fallers were similar.

CONCLUSION

The effect of BMD loss on risk of nonvertebral fracture may be greater in persons without a history of falls. It is possible that change in BMD contributes less to fracture risk when a strong risk factor for fracture, such as falls, is present.

Falls risk factors: assessment and management to prevent falls and fractures

Falls and fragility fractures are common, dangerous, and important public health challenges. They are best understood as geriatric syndromes with close relation to frailty and other aging-related health problems. They are associated with many risk factors, in all health domains - physical, psychological, social, and environmental. At a population level, the challenge is to improve the health and well-being of all older people to reduce the incidence of falls. At a clinical level, the challenge is to assess the individual risk factors and apply evidence-based individually tailored, multifactorial interventions. The most powerful component is strength-and-balance exercise training.

Impact of femoral neck and lumbar spine BMD discordances on FRAX probabilities in women: a meta-analysis of international cohorts

There are occasional marked discordances in BMD T-scores at the lumbar spine (LS) and femoral neck (FN). We investigated whether such discordances could contribute independently to fracture prediction using FRAX. We studied 21,158 women, average age 63 years, from 10 prospective cohorts with baseline FRAX variables as well as FN and LS BMD. Incident fractures were collected by self-report and/or radiographic reports. Extended Poisson regression examined the relationship between differences in LS and FN T-scores (ΔLS-FN) and fracture risk, adjusted for age, time since baseline and other factors including FRAX 10-year probability for major osteoporotic fracture calculated using FN BMD. To examine the effect of an adjustment for ΔLS-FN on reclassification, women were separated into risk categories by their FRAX major fracture probability. High risk was classified using two approaches: being above the National Osteoporosis Guideline Group intervention threshold or, separately, being in the highest third of each cohort. The absolute ΔLS-FN was greater than 2 SD for 2.5% of women and between 1 and 2 SD for 21%. ΔLS-FN was associated with a significant risk of fracture adjusted for baseline FRAX (HR per SD change = 1.09; 95% CI = 1.04-1.15). In reclassification analyses, only 2.3-3.2% of the women moved to a higher or lower risk category when using FRAX with ΔLS-FN compared with FN-derived FRAX alone. Adjustment of estimated fracture risk for a large LS/FN discrepancy (>2SD) impacts to a large extent on only a relatively small number of individuals. More moderate (1-2SD) discordances in FN and LS T-scores have a small impact on FRAX probabilities. This might still improve clinical decision-making, particularly in women with probabilities close to an intervention threshold.

Management of postmenopausal osteoporosis

A hallmark of menopause, which follows the decline in the ovarian production of estrogen, is the aggressive and persistent loss of bone mineral and structural elements leading to loss of bone strength and increased fracture risk. This review focuses on newer methods of diagnosing osteoporosis and assessing fracture risk, as well as on novel management strategies for prevention and treatment. Fracture-risk prediction has been significantly enhanced by the development of methods such as the trabecular bone score, which helps assess bone microarchitecture and adds value to standard bone densitometry, and the Fracture Risk Assessment Tool (FRAX) algorithm techniques. The treatment of osteoporosis, which has the goals of fracture prevention and risk reduction, is moving beyond traditional monotherapies with antiresorptives and anabolic agents into new combination regimens.

Spine bone texture assessed by trabecular bone score (TBS) predicts osteoporotic fractures in men: the Manitoba Bone Density Program

INTRODUCTION

One quarter of osteoporotic fractures occur in men. TBS, a gray-level measurement derived from lumbar spine DXA image texture, is related to microarchitecture and fracture risk independently of BMD. Previous studies reported the ability of spine TBS to predict osteoporotic fractures in women. Our aim was to evaluate the ability of TBS to predict clinical osteoporotic fractures in men.

METHODS

3620 men aged ≥50 (mean 67.6years) at the time of baseline DXA (femoral neck, spine) were identified from a database (Province of Manitoba, Canada). Health service records were assessed for the presence of non-traumatic osteoporotic fracture after BMD testing. Lumbar spine TBS was derived from spine DXA blinded to clinical parameters and outcomes. We used Cox proportional hazard regression to analyze time to first fracture adjusted for clinical risk factors (FRAX without BMD), osteoporosis treatment and BMD (hip or spine).

RESULTS

Mean followup was 4.5years. 183 (5.1%) men sustain major osteoporotic fractures (MOF), 91 (2.5%) clinical vertebral fractures (CVF), and 46 (1.3%) hip fractures (HF). Correlation between spine BMD and spine TBS was modest (r=0.31), less than correlation between spine and hip BMD (r=0.63). Significantly lower spine TBS were found in fracture versus non-fracture men for MOF (p<0.001), HF (p<0.001) and CVF (p=0.003). Area under the receiver operating characteristic curve (AUC) for incident fracture discrimination with TBS was significantly better than chance (MOF AUC=0.59, p<0.001; HF AUC=0.67, p<0.001; CVF AUC=0.57, p=0.032). TBS predicted MOF and HF (but not CVF) in models adjusted for FRAX without BMD and osteoporosis treatment. TBS remained a predictor of HF (but not MOF) after further adjustment for hip BMD or spine BMD.

CONCLUSION

We observed that spine TBS predicted MOF and HF independently of the clinical FRAX score, HF independently of FRAX and BMD in men. Studies with more incident fractures are needed to confirm these findings.

Hyperkyphosis, kyphosis progression, and risk of non-spine fractures in older community dwelling women: the study of osteoporotic fractures (SOF)

While accentuated kyphosis is associated with osteoporosis, it is unknown whether it increases risk of future fractures, independent of bone mineral density (BMD) and vertebral fractures. We examined the associations of baseline Cobb angle kyphosis and 15 year change in kyphosis with incident non-spine fractures using data from the Study of Osteoporotic Fractures. A total of 994 predominantly white women, aged 65 or older, were randomly sampled from 9704 original participants to have repeated Cobb angle measurements of kyphosis measured from lateral spine radiographs at baseline and an average of 15 years later. Non-spine fractures, confirmed by radiographic report, were assessed every 4 months for up to 21.3 years. Compared with women in the lower three quartiles of kyphosis, women with kyphosis greater than 53° (top quartile) had a 50% increased risk of non-spine fracture (95% CI, 1.10-2.06 after adjusting for BMD, prevalent vertebral fractures, prior history of fractures, and other fracture risk factors. Cobb angle kyphosis progressed an average of 7° (SD = 6.8) over 15 years. Per 1 SD increase in kyphosis change, there was a multivariable adjusted 28% increased risk of fracture (95% CI, 1.06-1.55) that was attenuated by further adjustment for baseline BMD (HR per SD increase in kyphosis change, 1.19; 95% CI 0.99-1.44). Greater kyphosis is associated with an elevated non-spine fracture risk independent of traditional fracture risk factors in older women. Furthermore, worsening kyphosis is also associated with increased fracture risk that is partially mediated by low baseline BMD that itself is a risk factor for kyphosis progression. These results suggest that randomized controlled fracture intervention trials should consider implementing kyphosis measures to the following: (1) further study kyphosis and kyphosis change as an additional fracture risk factor; and (2) test whether therapies may improve or delay its progression.

Bone quality: the determinants of bone strength and fragility

Bone fragility is a major health concern, as the increased risk of bone fractures has devastating outcomes in terms of mortality, decreased autonomy, and healthcare costs. Efforts made to address this problem have considerably increased our knowledge about the mechanisms that regulate bone formation and resorption. In particular, we now have a much better understanding of the cellular events that are triggered when bones are mechanically stimulated and how these events can lead to improvements in bone mass. Despite these findings at the molecular level, most exercise intervention studies reveal either no effects or only minor benefits of exercise programs in improving bone mineral density (BMD) in osteoporotic patients. Nevertheless, and despite that BMD is the gold standard for diagnosing osteoporosis, this measure is only able to provide insights regarding the quantity of bone tissue. In this article, we review the complex structure of bone tissue and highlight the concept that its mechanical strength stems from the interaction of several different features. We revisited the available data showing that bone mineralization degree, hydroxyapatite crystal size and heterogeneity, collagen properties, osteocyte density, trabecular and cortical microarchitecture, as well as whole bone geometry, are determinants of bone strength and that each one of these properties may independently contribute to the increased or decreased risk of fracture, even without meaningful changes in aBMD. Based on these findings, we emphasize that while osteoporosis (almost) always causes bone fragility, bone fragility is not always caused just by osteoporosis, as other important variables also play a major role in this etiology. Furthermore, the results of several studies showing compelling data that physical exercise has the potential to improve bone quality and to decrease fracture risk by influencing each one of these determinants are also reviewed. These findings have meaningful clinical repercussions as they emphasize the fact that, even without leading to improvements in BMD, exercise interventions in patients with osteoporosis may be beneficial by improving other determinants of bone strength.

Impacts of body mass index, physical activity, and smoking on femoral bone loss: the Tromsø study

Bone mineral density (BMD) is a reflection of bone strength and lifestyles that preserve bone mass and may reduce fracture risk in old age. This study examined the effect of combined profiles of smoking, physical activity, and body mass index (BMI) on lifetime bone loss. Data were collected from the population-based Tromsø Study. BMD was measured as g/cm(2) by dual-energy X-ray absorptiometry (DXA) at the total hip and femoral neck in 2580 women and 2084 men aged 30 to 80 years in the 2001-02 survey, and repeated in 1401 women and 1113 men in the 2007-08 survey. Height and weight were measured and lifestyle information was collected through questionnaires. Data were analyzed using linear mixed models with second-degree fractional polynomials. From the peak at the age around 40 years to 80 years of age, loss rates varied between 4% at the total hip and 14% at femoral neck in nonsmoking, physically active men with a BMI of 30 kg/m(2) to approximately 30% at both femoral sites in heavy smoking, physically inactive men with a BMI value of 18 kg/m(2) . In women also, loss rates of more than 30% were estimated in the lifestyle groups with a BMI value of 18 kg/m(2) . BMI had the strongest effect on BMD, especially in the oldest age groups, but a BMI above 30 kg/m(2) did not exert any additional effect compared with the population average BMI of 27 kg/m(2) . At the age of 80 years, a lifestyle of moderate BMI to light overweight, smoking avoidance, and physical activity of 4 hours of vigorous activity per week through adult life may result in 1 to 2 standard deviations higher BMD levels compared with a lifestyle marked by heavy smoking, inactivity, and low weight. In the prevention of osteoporosis and fracture risk, the effect of combined lifestyles through adult life should be highlighted. © 2014 American Society for Bone and Mineral Research.

Lumbar spine texture enhances 10-year fracture probability assessment

We found that lumbar spine texture analysis using trabecular bone score (TBS) is a risk factor for MOF and a risk factor for death in a retrospective cohort study from a large clinical registry for the province of Manitoba, Canada.

INTRODUCTION

FRAX® estimates the 10-year probability of major osteoporotic fracture (MOF) using clinical risk factors and femoral neck bone mineral density (BMD). Trabecular bone score (TBS), derived from texture in the spine dual X-ray absorptiometry (DXA) image, is related to bone microarchitecture and fracture risk independently of BMD. Our objective was to determine whether TBS provides information on MOF probability beyond that provided by the FRAX variables.

METHODS

We included 33,352 women aged 40-100 years (mean 63 years) with baseline DXA measurements of lumbar spine TBS and femoral neck BMD. The association between TBS, the FRAX variables, and the risk of MOF or death was examined using an extension of the Poisson regression model.

RESULTS

During the mean of 4.7 years, 1,754 women died and 1,872 sustained one or more MOF. For each standard deviation reduction in TBS, there was a 36 % increase in MOF risk (HR 1.36, 95 % CI 1.30-1.42, p < 0.001) and a 32 % increase in death (HR 1.32, 95 % CI 1.26-1.39, p < 0.001). When adjusted for significant clinical risk factors and femoral neck BMD, lumbar spine TBS was still a significant predictor of MOF (HR 1.18, 95 % CI 1.12-1.23) and death (HR 1.20, 95 % CI 1.14-1.26). Models for estimating MOF probability, accounting for competing mortality, showed that low TBS (10th percentile) increased risk by 1.5-1.6-fold compared with high TBS (90th percentile) across a broad range of ages and femoral neck T-scores.

CONCLUSIONS

Lumbar spine TBS is able to predict incident MOF independent of FRAX clinical risk factors and femoral neck BMD even after accounting for the increased death hazard.

Bone mineral density after bariatric surgery. A systematic review

PURPOSE

Bone regulation system may be affected after bariatric surgeries, but procedures impact differently to bone mineral density (BMD) and measures restraining bone loss are frequently neglected until clinical consequences become manifest. This is a systematic review aimed to elucidate whether BMD loss is comparable after different bariatric surgeries.

MATERIALS AND METHODS

A search of morbid obese adults, undergone to bariatric surgery, with BMD measured by dual-energy X-ray absorptiometry at baseline and after surgery studies was performed in several databases. Studies were assessed using the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) Statement and COCHRANE Risk of Bias tool. The random model was selected for meta-analysis; heterogeneity was analyzed with T(2), inconsistency (I(2) > 50%) and Chi(2) (p < 0.10). Level of evidence and strength of recommendations were summarized using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE System).

RESULTS

Twelve studies met the selection criteria. After one year, reduction in total BMD in patients with mixed surgical procedures was significant: -0.03 g/cm(2) (CI 95% 0.00 to -0.06, p < 0.05). BMD was reduced by -0.12 g/cm(2) (CI 95% -0.10 to -0.15, p < 0.001) in the hip, -0.07 g/cm(2) (CI 95% -0.03 to -0.11, p < 0.001) in the column, and -0.03 g/cm(2) (IC 95% -0.02 to -0.04, p < 0.001) in the forearm, but not in restrictive surgeries. Studies included showed high heterogeneity and low quality of evidence.

CONCLUSIONS

Patients undergone to mixed bariatric surgery had significant higher BMD deterioration as demonstrated in this review, suggesting that more attention for preventing fractures is required.

Antiepileptic medications increase osteoporosis risk in male fabry patients: bone mineral density in an Australian cohort

BACKGROUND

Fabry disease (FD) is an inherited X-linked lysosomal storage disease with widespread clinical manifestations. Small prospective studies have shown increased osteopenia and osteoporosis in male FD patients. Limited information however exists about bone metabolism and osteoporosis risk factors within this group. We reviewed osteoporosis risk factors within our cohort.

METHODS

A retrospective analysis of bone mineral density (BMD) results and fracture incidence in 44 patients (22 males and 22 females) was undertaken. Dual X-ray absorptiometry scans were performed at the lumbar spine, hip and femoral neck. The impact of risk factors including renal function, antiepileptic drug (AED), analgesia and vitamin D levels were assessed.

RESULTS

Male FD patients had low T scores at all sites (spine -1.2 ± 1.06, hip -1.6 ± 0.9, femoral neck -2.23 ± 1.01). Female T scores showed more typical distribution (spine -0.07 ± 1.47, hip 0.02 ± 1.14, femoral neck -0.49 ± 1.31). A higher incidence of osteopenia and/or osteoporosis occurred in males versus females (spine 46.9% versus 31.8%, hip 75.5% versus 18.2% and femoral neck 86.4% versus 45.5%). Multiple regression analysis showed a 50.8% (p < 0.001) reduction in femoral neck BMD with AED usage, after adjustment for age, gender and renal function. Non-traumatic fractures occurred in 27.3% males over 205 patient-years versus 4.6% in females over 149 patient-years, p = 0.095.

CONCLUSIONS

Low bone density was highly prevalent in male patients with increased incidence of non-traumatic fractures. AED usage significantly reduces BMD. Treatment to prevent BMD deterioration will depend on determining the bone turnover status.

Baboons as a model to study genetics and epigenetics of human disease

A major challenge for understanding susceptibility to common human diseases is determining genetic and environmental factors that influence mechanisms underlying variation in disease-related traits. The most common diseases afflicting the US population are complex diseases that develop as a result of defects in multiple genetically controlled systems in response to environmental challenges. Unraveling the etiology of these diseases is exceedingly difficult because of the many genetic and environmental factors involved. Studies of complex disease genetics in humans are challenging because it is not possible to control pedigree structure and often not practical to control environmental conditions over an extended period of time. Furthermore, access to tissues relevant to many diseases from healthy individuals is quite limited. The baboon is a well-established research model for the study of a wide array of common complex diseases, including dyslipidemia, hypertension, obesity, and osteoporosis. It is possible to acquire tissues from healthy, genetically characterized baboons that have been exposed to defined environmental stimuli. In this review, we describe the genetic and physiologic similarity of baboons with humans, the ability and usefulness of controlling environment and breeding, and current genetic and genomic resources. We discuss studies on genetics of heart disease, obesity, diabetes, metabolic syndrome, hypertension, osteoporosis, osteoarthritis, and intrauterine growth restriction using the baboon as a model for human disease. We also summarize new studies and resources under development, providing examples of potential translational studies for targeted interventions and therapies for human disease.

Osteoporosis and fragility fractures: Vertebral fractures

The incidence of vertebral fragility fractures and deformity increase steeply with age. Every sixth woman and every twelfth man will sustain a symptomatic vertebral fracture. Vertebral fractures result in pain, functional disability and decreased quality of life, which may last for several years, and may also affect mortality. The patient with an acute fracture should be examined with radiology for diagnosis. In case of a low-energy fracture, osteoporosis should be suspected and investigated. If the pain management fails, vertebroplasty or kyphoplasty could be considered. Braces may be used, but evidence for its effect is lacking. In the rare event of neurological compromise, or unstable fractures, surgical treatment should be considered. After vertebral fragility fractures, the risk for new fractures is high and secondary preventive measures advocated. The best evidence for secondary prevention is currently on medical treatment of osteoporosis.

Implications of expanding indications for drug treatment to prevent fracture in older men in United States: cross sectional and longitudinal analysis of prospective cohort study

OBJECTIVES

To quantify incremental effects of applying different criteria to identify men who are candidates for drug treatment to prevent fracture and to examine the extent to which fracture probabilities vary across distinct categories of men defined by these criteria.

DESIGN

Cross sectional and longitudinal analysis of a prospective cohort study.

SETTING

Multicenter Osteoporotic Fractures in Men (MrOS) study in the United States.

PARTICIPANTS

5880 untreated community dwelling men aged 65 years or over classified into four distinct groups: osteoporosis by World Health Organization criteria alone; osteoporosis by National Osteoporosis Foundation (NOF) but not WHO criteria; no osteoporosis but at high fracture risk (at or above NOF derived FRAX intervention thresholds recommended for US); and no osteoporosis and at low fracture risk (below NOF derived FRAX intervention thresholds recommended for US).

MAIN OUTCOME MEASURES

Proportion of men identified for drug treatment; predicted 10 year probabilities of hip and major osteoporotic fracture calculated using FRAX algorithm with femoral neck bone mineral density; observed 10 year probabilities for confirmed incident hip and major osteoporotic (hip, clinical vertebral, wrist, or humerus) fracture events calculated using cumulative incidence estimation, accounting for competing risk of mortality.

RESULTS

130 (2.2%) men were identified as having osteoporosis by using the WHO definition, and an additional 422 were identified by applying the NOF definition (total osteoporosis prevalence 9.4%). Application of NOF derived FRAX intervention thresholds led to 936 (15.9%) additional men without osteoporosis being identified as at high fracture risk, raising the total prevalence of men potentially eligible for drug treatment to 25.3%. Observed 10 year hip fracture probabilities were 20.6% for men with osteoporosis by WHO criteria alone, 6.8% for men with osteoporosis by NOF (but not WHO) criteria, 6.4% for men without osteoporosis but classified as at high fracture risk, and 1.5% for men without osteoporosis and classified as at low fracture risk. A similar pattern was noted in observed fracture probabilities for major osteoporotic fracture. Among men with osteoporosis by WHO criteria, observed fracture probabilities were greater than FRAX predicted probabilities (20.6% v 9.5% for hip fracture and 30.0% v 17.4% for major osteoporotic fracture).

CONCLUSIONS AND RELEVANCE

Choice of definition of osteoporosis and use of NOF derived FRAX intervention thresholds have major effects on the proportion of older men identified as warranting drug treatment to prevent fracture. Among men identified with osteoporosis by WHO criteria, who comprised 2% of the study population, actual observed fracture probabilities during 10 years of follow-up were highest and exceeded FRAX predicted fracture probabilities. On the basis of findings from randomized trials in women, these men are most likely to benefit from treatment. Expanding indications for treatment beyond this small group has uncertain value owing to lower observed fracture probabilities and uncertain benefits of treatment among men not selected on the basis of WHO criteria.

The importance of previous fracture site on osteoporosis diagnosis and incident fractures in women

Previous fracture increases the risk of subsequent fractures regardless of the site of the initial fracture. Fracture risk assessment tools have been developed to guide clinical management; however, no discrimination is made as to the site of the prior fracture. Our objective was to determine which sites of previous nontraumatic fractures are most strongly associated with a diagnosis of osteoporosis, defined by a bone mineral density (BMD) T-score of ≤ -2.5 at the femoral neck, and an incident major osteoporotic fracture. Using administrative health databases, we conducted a retrospective historical cohort study of 39,991 women age 45 years and older who had BMD testing with dual-energy X-ray absorptiometry (DXA). Logistic regression and Cox proportional multivariate models were used to test the association of previous fracture site with risk of osteoporosis and incident fractures. Clinical fractures at the following sites were strongly and independently associated with higher risk of an osteoporotic femoral neck T-score after adjustment for age: hip (odds ratio [OR], 3.58; 95% confidence interval [CI], 3.04-4.21), pelvis (OR, 2.23; 95% CI, 1.66-3.0), spine (OR, 2.16; 95% CI, 1.77-2.62), and humerus (OR, 1.74; 95% CI, 1.49-2.02). Cox proportional hazards models, with adjustment for age and femoral neck BMD, showed the greatest increase in risk for a major osteoporotic fracture for women who had sustained previous fractures of the spine (hazard ratio [HR], 2.08; 95% CI, 1.72-2.53), humerus (HR, 1.70; 95% CI, 1.44-2.01), patella (HR, 1.54; 95% CI, 1.10-2.18), and pelvis (HR, 1.45; 95% CI, 1.04-2.02). In summary, our results confirm that nontraumatic fractures in women are associated with osteoporosis at the femoral neck and that the site of previous fracture impacts on future osteoporotic fracture risk, independent of BMD.

A hybrid FDTD-Rayleigh integral computational method for the simulation of the ultrasound measurement of proximal femur

The development of novel quantitative ultrasound (QUS) techniques to measure the hip is critically dependent on the possibility to simulate the ultrasound propagation. One specificity of hip QUS is that ultrasounds propagate through a large thickness of soft tissue, which can be modeled by a homogeneous fluid in a first approach. Finite difference time domain (FDTD) algorithms have been widely used to simulate QUS measurements but they are not adapted to simulate ultrasonic propagation over long distances in homogeneous media. In this paper, an hybrid numerical method is presented to simulate hip QUS measurements. A two-dimensional FDTD simulation in the vicinity of the bone is coupled to the semi-analytic calculation of the Rayleigh integral to compute the wave propagation between the probe and the bone. The method is used to simulate a setup dedicated to the measurement of circumferential guided waves in the cortical compartment of the femoral neck. The proposed approach is validated by comparison with a full FDTD simulation and with an experiment on a bone phantom. For a realistic QUS configuration, the computation time is estimated to be sixty times less with the hybrid method than with a full FDTD approach.

Prevention and treatment of postmenopausal osteoporosis

In the beginning, that is from the 1960's, when a link between menopause and osteoporosis was first identified; estrogen treatment was the standard for preventing bone loss, however there was no fracture data, even though it was thought to be effective. This continued until the Women's Health Initiative (WHI) study in 2001 that published data on 6 years of treatment with hormone therapy that showed an increase in heart attacks and breast cancer. Even though the risks were small, 1 per 1500 users annually, patients were worried and there was a large drop off in estrogen use. In later analyses the WHI study showed that estrogen reduced fractures and actually prevented heart attacks in the 50-60 year age group. Estrogen alone appeared to be safer to use than estrogen+the progestin medroxyprogesterone acetate and actually reduced breast cancer. At the same time other drugs were being developed for bone that belong to the bisphosphonate group and the first generation of compounds showed moderate potency on bone resorption. The second and third generation compounds were much more potent and in a series of large trials were shown to reduce fractures. For the last 15 years the treatment of osteoporosis belonged to the bisphosphonate compounds, most of which reduce fracture rates by 50 percent. With the exception of gastrointestinal irritation the drugs are well tolerated and highly effective. The sophistication of the delivery systems now allow treatment that can be given daily, weekly, monthly and annually either orally or intravenously. Bone remodeling is a dynamic process that repairs microfractures and replaces old bone with new bone. In the last 10 years there has been a remarkable understanding of bone biology so that new therapies can be specifically designed on a biological basis. The realization that RANKL was the final cytokine involved in the resorption process and that marrow cells produced a natural antagonist called Osteoprotegerin (OPG) quickly led to two lines of therapy. First OPG was used as a therapy to block RANKL was initially successful but later antibodies against OPG developed and this line of treatment had to be discontinued. The next step was to develop a monoclonal antibody against RANKL and this proved to be highly effective in blocking bone resorption. It led to development of a drug Denosumab that successfully reduces fractures and is now one of the therapeutic options for osteoporosis treatment. On the anabolic side bone biology research showed that osteocytes produces sclerostin an inhibitor of the anabolic WNT signaling pathway. Recent development of a monoclonal antibody against sclerostin has shown remarkable anabolic activity in bone showing large increases in bone density and fracture trials are now underway. The newer treatments for osteoporosis are likely to be based on our understanding of bone biology and the design of new highly specific compounds with fewer side effects. This review summarizes the diagnosis of postmenopausal osteoporosis and various available non-pharmacological and pharmacological therapies available for its management. This article is part of a Special Issue entitled 'Menopause'.

Bone quality assessment in type 2 diabetes mellitus

The increased risk for fractures in type 2 diabetes mellitus (T2DM) despite higher average bone density is unexplained. This study assessed trabecular bone quality in T2DM using the trabecular bone score (TBS). The salient findings are that TBS is decreased in T2DM and low TBS associates with worse glycemic control.

INTRODUCTION

Type 2 diabetes mellitus is a risk factor for osteoporotic fractures despite high average bone mineral density (BMD). The aim of this study was to compare BMD with a noninvasive assessment of trabecular microarchitecture, TBS, in women with T2DM.

METHODS

In a cross-sectional study, trabecular microarchitecture was examined in 57 women with T2DM and 43 women without diabetes, ages 30 to 90 years. Lumbar spine BMD was measured by dual-emission x-ray absorptiometry (DXA), and TBS was calculated by examining pixel variations within the DXA images utilizing TBS iNsight software.

RESULTS

Mean TBS was lower in T2DM (1.228 ± 0.140 vs. 1.298 ± 0.132, p = 0.013), irrespective of age. Mean BMD was higher in T2DM (1.150 ± 0.172 vs. 1.051 ± 0.125, p = 0.001). Within the T2DM group, TBS was higher (1.254 ± 0.148) in subjects with good glycemic control (A1c ≤ 7.5 %) compared to those (1.166 ± 0.094; p = 0.01) with poor glycemic control (A1c > 7.5 %).

CONCLUSION

In T2DM, TBS is lower and associated with poor glycemic control. Abnormal trabecular microarchitecture may help explain the paradox of increased fractures at a higher BMD in T2DM. Further studies are needed to better understand the relationship between glycemic control and trabecular bone quality.

Insights from the Global Longitudinal Study of Osteoporosis in Women (GLOW)

GLOW is an observational, longitudinal, practice-based cohort study of osteoporosis in 60,393 women aged ≥55 years in 10 countries on three continents. In this Review, we present insights from the first 3 years of the study. Despite cost analyses being frequently based on spine and hip fractures, we found that nonvertebral, nonhip fractures were around five times more common and doubled the use of health-care resources compared with hip and spine fractures combined. Fractures not at the four so-called major sites in FRAX(®) (upper arm, forearm, hip and clinical vertebral fractures) account for >40% of all fractures. The risk of fracture is increased by various comorbidities, such as Parkinson disease, multiple sclerosis and lung and heart disease. Obesity, although thought to be protective against all fractures, substantially increased the risk of fractures in the ankle or lower leg. Simple assessment by age plus fracture history has good predictive value for all fractures, but risk profiles differ for first and subsequent fractures. Fractures diminish quality of life as much or more than diabetes mellitus, arthritis and lung disease, yet women substantially underestimate their own fracture risk. Treatment rates in patients at high risk of fracture are below those recommended but might be too frequent in women at low risk. Comorbidities and the limits of current therapeutic regimens jeopardize the efficacy of drugs; new regimens should be explored for severe cases.

Clinical Trials Express: fracture risk reduction with denosumab in Japanese postmenopausal women and men with osteoporosis: denosumab fracture intervention randomized placebo controlled trial (DIRECT)

CONTEXT

Denosumab 60 mg sc injection every 6 months for 36 months was well tolerated and effective in reducing the incidence of vertebral, nonvertebral, and hip fracture in predominantly Caucasian postmenopausal women with osteoporosis.

OBJECTIVE

The objective of this phase 3 fracture study was to examine the antifracture efficacy and safety of denosumab 60 mg in Japanese women and men with osteoporosis compared with placebo.

DESIGN AND SETTING

A randomized, double-blind, placebo-controlled trial with an open-label active comparator as a referential arm was conducted.

PATIENTS

Subjects were 1262 Japanese patients with osteoporosis aged 50 years or older, who had one to four prevalent vertebral fractures.

INTERVENTION

Subjects were randomly assigned to receive denosumab 60 mg sc every 6 months (n = 500), placebo for denosumab (n = 511), or oral alendronate 35 mg weekly (n = 251). All subjects received daily supplements of calcium and vitamin D.

MAIN OUTCOME MEASURE

The primary endpoint was the 24-month incidence of new or worsening vertebral fracture for denosumab vs placebo.

RESULTS

Denosumab significantly reduced the risk of new or worsening vertebral fracture by 65.7%, with incidences of 3.6% in denosumab and 10.3% in placebo at 24 months (hazard ratio 0.343; 95% confidence interval 0.194-0.606, P = .0001). No apparent difference in adverse events was found between denosumab and placebo during the first 24 months of the study.

CONCLUSION

These results provide evidence of the efficacy and safety of denosumab 60 mg sc every 6 months in Japanese subjects with osteoporosis.

Expected lifetime numbers and costs of fractures in postmenopausal women with and without osteoporosis in Germany: a discrete event simulation model

BACKGROUND

Osteoporotic fractures cause a large health burden and substantial costs. This study estimated the expected fracture numbers and costs for the remaining lifetime of postmenopausal women in Germany.

METHODS

A discrete event simulation (DES) model which tracks changes in fracture risk due to osteoporosis, a previous fracture or institutionalization in a nursing home was developed. Expected lifetime fracture numbers and costs per capita were estimated for postmenopausal women (aged 50 and older) at average osteoporosis risk (AOR) and for those never suffering from osteoporosis. Direct and indirect costs were modeled. Deterministic univariate and probabilistic sensitivity analyses were conducted.

RESULTS

The expected fracture numbers over the remaining lifetime of a 50 year old woman with AOR for each fracture type (% attributable to osteoporosis) were: hip 0.282 (57.9%), wrist 0.229 (18.2%), clinical vertebral 0.206 (39.2%), humerus 0.147 (43.5%), pelvis 0.105 (47.5%), and other femur 0.033 (52.1%). Expected discounted fracture lifetime costs (excess cost attributable to osteoporosis) per 50 year old woman with AOR amounted to € 4,479 (€ 1,995). Most costs were accrued in the hospital € 1,743 (€ 751) and long-term care sectors € 1,210 (€ 620). Univariate sensitivity analysis resulted in percentage changes between -48.4% (if fracture rates decreased by 2% per year) and +83.5% (if fracture rates increased by 2% per year) compared to base case excess costs. Costs for women with osteoporosis were about 3.3 times of those never getting osteoporosis (€ 7,463 vs. € 2,247), and were markedly increased for women with a previous fracture.

CONCLUSION

The results of this study indicate that osteoporosis causes a substantial share of fracture costs in postmenopausal women, which strongly increase with age and previous fractures.

A cross-sectional multicenter study of osteogenesis imperfecta in North America - results from the linked clinical research centers

Osteogenesis imperfecta (OI) is the most common skeletal dysplasia that predisposes to recurrent fractures and bone deformities. In spite of significant advances in understanding the genetic basis of OI, there have been no large-scale natural history studies. To better understand the natural history and improve the care of patients, a network of Linked Clinical Research Centers (LCRC) was established. Subjects with OI were enrolled in a longitudinal study, and in this report, we present cross-sectional data on the largest cohort of OI subjects (n = 544). OI type III subjects had higher prevalence of dentinogenesis imperfecta, severe scoliosis, and long bone deformities as compared to those with OI types I and IV. Whereas the mean lumbar spine area bone mineral density (LS aBMD) was low across all OI subtypes, those with more severe forms had lower bone mass. Molecular testing may help predict the subtype in type I collagen-related OI. Analysis of such well-collected and unbiased data in OI can not only help answering questions that are relevant to patient care but also foster hypothesis-driven research, especially in the context of 'phenotypic expansion' driven by next-generation sequencing.

Modeling of femoral neck cortical bone for the numerical simulation of ultrasound propagation

Quantitative ultrasound assessment of the cortical compartment of the femur neck (FN) is investigated with the goal of achieving enhanced fracture risk prediction. Measurements at the FN are influenced by bone size, shape and material properties. The work described here was aimed at determining which FN material properties have a significant impact on ultrasound propagation around 0.5 MHz and assessing the relevancy of different models. A methodology for the modeling of ultrasound propagation in the FN, with a focus on the modeling of bone elastic properties based on scanning acoustic microscopy data, is introduced. It is found that the first-arriving ultrasound signal measured in through-transmission at the FN is not influenced by trabecular bone properties or by the heterogeneities of the cortical bone mineralized matrix. In contrast, the signal is sensitive to variations in cortical porosity, which can, to a certain extent, be accounted for by effective properties calculated with the Mori-Tanaka method.

Finite element analysis applied to 3-T MR imaging of proximal femur microarchitecture: lower bone strength in patients with fragility fractures compared with control subjects

PURPOSE

To determine the feasibility of using finite element analysis applied to 3-T magnetic resonance (MR) images of proximal femur microarchitecture for detection of lower bone strength in subjects with fragility fractures compared with control subjects without fractures.

MATERIALS AND METHODS

This prospective study was institutional review board approved and HIPAA compliant. Written informed consent was obtained. Postmenopausal women with (n = 22) and without (n = 22) fragility fractures were matched for age and body mass index. All subjects underwent standard dual-energy x-ray absorptiometry. Images of proximal femur microarchitecture were obtained by using a high-spatial-resolution three-dimensional fast low-angle shot sequence at 3 T. Finite element analysis was applied to compute elastic modulus as a measure of strength in the femoral head and neck, Ward triangle, greater trochanter, and intertrochanteric region. The Mann-Whitney test was used to compare bone mineral density T scores and elastic moduli between the groups. The relationship (R(2)) between elastic moduli and bone mineral density T scores was assessed.

RESULTS

Patients with fractures showed lower elastic modulus than did control subjects in all proximal femur regions (femoral head, 8.51-8.73 GPa vs 9.32-9.67 GPa; P = .04; femoral neck, 3.11-3.72 GPa vs 4.39-4.82 GPa; P = .04; Ward triangle, 1.85-2.21 GPa vs 3.98-4.13 GPa; P = .04; intertrochanteric region, 1.62-2.18 GPa vs 3.86-4.47 GPa; P = .006-.007; greater trochanter, 0.65-1.21 GPa vs 1.96-2.62 GPa; P = .01-.02), but no differences in bone mineral density T scores. There were weak relationships between elastic moduli and bone mineral density T scores in patients with fractures (R(2) = 0.25-0.31, P = .02-.04), but not in control subjects. CONCLUSION Finite element analysis applied to high-spatial-resolution 3-T MR images of proximal femur microarchitecture can allow detection of lower elastic modulus, a marker of bone strength, in subjects with fragility fractures compared with control subjects. MR assessment of proximal femur strength may provide information about bone quality that is not provided by dual-energy x-ray absorptiometry.

Chemical structure, biosynthesis and synthesis of free and glycosylated pyridinolines formed by cross-link of bone and synovium collagen

This review focuses on the chemical structure, biosynthesis and synthesis of free and glycosylated pyridinolines (Pyds), fluorescent collagen cross-links, with a pyridinium salt structure. Pyds derive from the degradation of bone collagen and have attracted attention for their use as biochemical markers of bone resorption and to assess fracture risk prediction in persons suffering from osteoporosis, bone cancer and other bone or collagen diseases. We consider and critically discuss all reported syntheses of free and glycosylated Pyds evidencing an unrevised chemistry, original and of general utility, analysis of which allows us to also support a previously suggested non-enzymatic formation of Pyds in collagen better rationalizing and justifying the chemical events.

Impact of androgen suppression and zoledronic acid on bone mineral density and fractures in the Trans-Tasman Radiation Oncology Group (TROG) 03.04 Randomised Androgen Deprivation and Radiotherapy (RADAR) randomized controlled trial for locally advanced prostate cancer

OBJECTIVE

To study the influence of adjuvant androgen suppression and bisphosphonates on incident vertebral and non-spinal fracture rates and bone mineral density (BMD) in men with locally advanced prostate cancer.

PATIENTS AND METHODS

Between 2003 and 2007, 1071 men with locally advanced prostate cancer were randomly allocated, using a 2 × 2 trial design, to 6 months i.m. leuprorelin (androgen suppression [AS]) before radiotherapy alone ± 12 months additional leuprorelin ± 18 months zoledronic acid (ZdA), commencing at randomization. The main endpoint was incident thoraco-lumbar vertebral fractures, which were assessed radiographically at randomization and at 3 years, then reassessed by centralized review. Subsidiary endpoints included incident non-spinal fractures, which were documented throughout follow-up, and BMD, which was measured in 222 subjects at baseline, 2 years and 4 years.

RESULTS

Incident vertebral fractures at 3 years were observed in 132 subjects. Their occurrence was not increased by 18 months' AS, nor reduced by ZdA. Incident non-spinal fractures occurred in 72 subjects and were significantly related to AS duration but not to ZdA. Osteopenia and osteoporosis prevalence rates at baseline were 23.4 and 1.4%, respectively, at the hip. Treatment for 6 and 18 months with AS caused significant reductions in hip BMD at 2 and 4 years (P < 0.01) and ZdA prevented these losses at both time points.

CONCLUSION

In an AS-naïve population, 18 months of ZdA treatment prevented the sustained BMD losses caused by 18 months of AS treatment; however, the study power was insufficient to show that AS duration or ZdA influenced vertebral fracture rates.

The 'Ossebo' intervention for the prevention of injurious falls in elderly women: background and design

This paper reviews the literature that contributed to the design of the 'Ossébo' intervention and describes the study that is underway.

BACKGROUND

Falls and fall-related injuries are a major cause of morbidity and mortality among older people. Extensive research into falls prevention has established physical exercise as an efficient method to reduce falls, but the effect of exercise on serious injuries caused by falls remains unclear. Moreover, populations that would benefit most from these interventions, as well as factors that determine adherence to exercise remain underreported. THE OSSÉBO INTERVENTION: 'Ossébo' is an on-going multicenter randomized controlled trial, aiming to assess the effect of a two-year community-based group physical exercise program on the prevention of falls among women aged 75-85 years old. The primary outcome examined is the rate of falls and injurious falls: secondary outcomes include functional capacities, fear of falling and quality of life. This study will help determine the effectiveness of a large scale falls prevention program and the factors that can potentially assist its success.

The associations between QCT-based vertebral bone measurements and prevalent vertebral fractures depend on the spinal locations of both bone measurement and fracture

We examined how spinal location affects the relationships between quantitative computed tomography (QCT)-based bone measurements and prevalent vertebral fractures. Upper spine (T4-T10) fractures appear to be more strongly related to bone measures than lower spine (T11-L4) fractures, while lower spine measurements are at least as strongly related to fractures as upper spine measurements.

INTRODUCTION

Vertebral fracture (VF), a common injury in older adults, is most prevalent in the mid-thoracic (T7-T8) and thoracolumbar (T12-L1) areas of the spine. However, measurements of bone mineral density (BMD) are typically made in the lumbar spine. It is not clear how the associations between bone measurements and VFs are affected by the spinal locations of both bone measurements and VF.

METHODS

A community-based case-control study includes 40 cases with moderate or severe prevalent VF and 80 age- and sex-matched controls. Measures of vertebral BMD, strength (estimated by finite element analysis), and factor of risk (load:strength ratio) were determined based on QCT scans at the L3 and T10 vertebrae. Associations were determined between bone measures and prevalent VF occurring at any location, in the upper spine (T4-T10), or in the lower spine (T11-L4).

RESULTS

Prevalent VF at any location was significantly associated with bone measures, with odds ratios (ORs) generally higher for measurements made at L3 (ORs = 1.9-3.9) than at T10 (ORs = 1.5-2.4). Upper spine fracture was associated with these measures at both T10 and L3 (ORs = 1.9-8.2), while lower spine fracture was less strongly associated (ORs = 1.0-2.4) and only reached significance for volumetric BMD measures at L3.

CONCLUSIONS

Closer proximity between the locations of bone measures and prevalent VF does not strengthen associations between bone measures and fracture. Furthermore, VF etiology may vary by region, with VFs in the upper spine more strongly related to skeletal fragility.

Persistent mucosal damage and risk of fracture in celiac disease

CONTEXT

Celiac disease (CD) is associated with an increased fracture risk, an increase that persists after diagnosis. A significant proportion of patients with CD have persistent villous atrophy (VA) on follow-up biopsy.

OBJECTIVE

The objective of the study was to determine whether persistent VA impacts long-term fracture risk.

DESIGN

This was a cohort study.

SETTING AND PATIENTS

We identified all patients in Sweden with histological evidence of CD who underwent a follow-up biopsy and compared patients with persistent VA with those with mucosal healing.

MAIN OUTCOME MEASURES

The following were measured: 1) any fracture; 2) likely osteoporotic fracture (defined as fractures of the hip, distal forearm, thoracic and lumbar spine, or proximal humerus); and 3) hip fracture.

RESULTS

Of 7146 patients, VA was present on follow-up biopsy in 43%. There was no significant association between persistent VA and overall fractures [hazard ratio (HR) of persistent VA compared with those with healing 0.93, 95% confidence interval (CI) 0.82-1.06] or with likely osteoporotic fractures (HR 1.11, 95% CI 0.84-1.46). Persistent VA was associated with an increased risk of hip fracture (HR 1.67, 95% CI 1.05-2.66). Hip fracture risk increased, depending on the degree of VA (HR for partial VA compared with those with healing 1.70, 95% CI 0.82-3.49, HR for subtotal/total VA compared with those with healing 2.16, 95% CI 1.06-4.41).

CONCLUSIONS

Persistent VA on follow-up biopsy is predictive of hip fracture risk. The association between persistent VA and hip fractures, but not fractures overall, implies that thinner sc tissue and fall or trauma may be mechanisms by which persistent VA confers an increased fracture risk.

Fracture risk prediction using phalangeal bone mineral density or FRAX(®)?-A Danish cohort study on men and women

In this prospective study, we investigated the ability of Fracture Risk Assessment Tool (FRAX), phalangeal bone mineral density (BMD), and age alone to predict fractures using data from a Danish cohort study, Danish Health Examination Survey 2007-2008, including men (n = 5206) and women (n = 7552) aged 40-90 yr. Data were collected using a self-administered questionnaire and by phalangeal BMD measurement. Information on incident and prevalent fractures, rheumatoid arthritis, and secondary osteoporosis was retrieved from the Danish National Patient Registry. Survival analyses were used to examine the association between low, intermediate, and high risk by phalangeal T-score or FRAX and incident fractures, and receiver operating characteristic curves were obtained. Mean follow-up time was 4.3 yr, and a total of 395 persons (3.1%) experienced a fracture during follow-up. The highest rate of major osteoporotic fractures was observed in persons with a high combined risk (FRAX ≥20% and T-score ≤-2.5; women: 32.7 and men: 27.6 per 1000 person-yr). This group also had the highest risk of hip fractures (women: 8.1 and men: 7.2 per 1000 person-yr). FRAX and T-score in combination analyzed as continuous variables performed overall best in the prediction of major osteoporotic fractures. In predicting hip fractures, there was a tendency of T-score performing worse than the other methods.

Mild morphometric vertebral fractures predict vertebral fractures but not non-vertebral fractures

In this meta-analysis of the control arms of four phase 3 trials, mild vertebral fractures were a significant risk factor for future vertebral fractures but not for non-vertebral fracture.

INTRODUCTION

A prior vertebral fracture is a risk factor for future fracture that is commonly used as an eligibility criterion for treatment and in the assessment of fracture probability. The aim of this study was to determine the prognostic significance of a morphometric fracture according to the severity of fracture.

METHODS

We examined the control (placebo) treated arms of four phase 3 trials. Vertebral fracture status was graded at baseline in 7,623 women, and fracture outcomes were documented over the subsequent 20,000 patient-years. Fracture outcomes were characterised as a further vertebral fracture, a non-vertebral fracture or a clinical fracture (non-vertebral plus clinical vertebral fracture). The relative risk of fracture was computed from the merged β coefficients of each trial weighted according to the variance.

RESULTS

Mild vertebral fractures were a significant risk factor for vertebral fractures [risk ratio (RR) = 2.17; 95% CI = 1.70-2.76] but were not associated with an increased risk of non-vertebral fractures (RR = 1.08; 95% CI = 0.86-1.36). Moderate/severe vertebral fractures were associated with a high risk of vertebral fractures (RR = 4.23; 95% CI = 3.58-5.00) and a moderate though significant increase in non-vertebral fracture risk (RR = 1.64; 95% CI = 1.38-1.94).

CONCLUSIONS

Prior moderate/severe morphometric vertebral fractures are a strong and significant risk factor for future fracture. The presence of a mild vertebral fracture is of no significant prognostic value for non-vertebral fractures. These findings should temper the use of morphometric fractures in the assessment of risk and the design of phase 3 studies.

Comparative cost-effectiveness of bazedoxifene and raloxifene in the treatment of postmenopausal osteoporosis in Europe, using the FRAX algorithm

Bazedoxifene and raloxifene were evaluated in the treatment of postmenopausal osteoporosis from health economic perspective in Europe. Based on a computer-based algorithm calculating efficacy of the treatments, bazedoxifene appears to be a cost-effective strategy compared to raloxifene, particularly in patients at high fracture risk.

INTRODUCTION

The purpose of this study was to compare cost-effectiveness of bazedoxifene and raloxifene in eight European countries: Belgium, France, Germany, Ireland, Italy, Spain, Sweden, and the UK.

METHODS

The Fracture Risk Assessment Tool, which is a computer-based algorithm to calculate fracture probability using clinical risk factors alone or with bone mineral density, was incorporated in a Markov Tunnel model to evaluate cost-effectiveness of bazedoxifene 20 or 40 mg vs. raloxifene 60 mg in postmenopausal osteoporotic women. The efficacy of bazedoxifene and raloxifene for vertebral and non-vertebral fractures was measured as a function of the 10-year probability of a major osteoporotic fracture. The model estimated the incremental cost-effectiveness ratio and net monetary benefit (NMB) from a healthcare perspective, given the willingness to pay <euro>30,000.

RESULTS

In postmenopausal osteoporotic women, bazedoxifene was a cost saving strategy compared to raloxifene in the countries studied. The median NMB of bazedoxifene compared to raloxifene increased monotonically with the 10-year fracture probability. In general, the median NMB became greater than 0 in women with 10-year probabilities of a major osteoporotic fracture between 5 and 10% or above. The impact on results by varying the assumptions in the model was examined in sensitivity analysis.

CONCLUSION

Bazedoxifene appears to be a cost-effective strategy compared to raloxifene for the treatment of postmenopausal osteoporotic women in Europe, particularly in patients at high fracture risk.

Added value of trabecular bone score over bone mineral density for identification of vertebral fractures in patients with areal bone mineral density in the non-osteoporotic range

Detection of patients with vertebral fracture is similar for areal bone mineral density (aBMD) and trabecular bone score (TBS) in patients with non-vertebral fracture. In non-osteoporotic patients, TBS adds information to lumbar spine aBMD and is related to an index of spine deterioration.

INTRODUCTION

Vertebral fractures (VFs) are more predictive of future fracture than aBMD. The number and severity of VFs are related to microarchitecture deterioration. TBS has been shown to be related to microarchitecture. The study aimed at evaluating TBS in the prediction of the presence and severity of VFs.

METHODS

Patients were selected from a Fracture Liaison Service (FLS): aBMD and vertebral fracture assessment (VFA) were assessed after the fracture, using dual-energy X-ray-absorptiometry (DXA). VFs were classified using Genant's semiquantitative method and severity, using the spinal deformity index (SDI). TBS was obtained after analysis of DXA scans. Performance of TBS and aBMD was assessed using areas under the curves (AUCs).

RESULTS

A total of 362 patients (77.3% women; mean age 74.3 ± 11.7 years) were analysed. Prevalence of VFs was 36.7%, and 189 patients (52.2%) were osteoporotic. Performance of TBS was similar to lumbar spine (LS) aBMD and hip aBMD for the identification of patients with VFs. In the population with aBMD in the non-osteoporotic range (n = 173), AUC of TBS for the discrimination of VFs was higher than the AUC of LS aBMD (0.670 vs 0.541, p = 0.035) but not of hip aBMD; there was a negative correlation between TBS and SDI (r = -0.31; p < 0.0001).

CONCLUSION

Detection of patients with vertebral fracture is similar for aBMD and TBS in patients with non-vertebral fracture. In patients with aBMD in the non-osteoporotic range, TBS adds information to lumbar spine aBMD alone and is related to an index of spine deterioration.

Dual-energy x-ray absorptiometry scan autoanalysis vs manual analysis

The measurement of bone mineral density (BMD) with dual-energy x-ray absorptiometry (DXA) is valuable for the determination of 10-yr fracture risk and for antifracture treatment follow-up. Ensuring patient scans are performed with accuracy, and reliability is imperative, requiring both technician competence and regular machine calibration. With DXA, analysis of each scan can be performed either with the machine's default autoanalysis or can be optimized manually. For 1 yr, all patients sent for DXA measurements to the Saskatoon Osteoporosis Center had each lumbar spine and hip scan analyzed with both manual and autoanalysis methods and the 2 sets of scans compared. We compared the concordance between the 2 analysis methods by calculating a BMD percent error for all of the scans, with the manually adjusted scans acting as the reference standard. Mann-Whitney U tests were completed to test for statistically significance differences between analysis types. In this investigation, scans completed with manual analysis were more accurate with respect to BMD (up to 4.7% error) and T-scores (up to 0.38 difference). In addition, many errors were identified with autoanalysis. Consequently, technicians using DXA should not rely on autoanalysis but rather be trained in and use manual analysis.

Utility of heel dual-energy X-ray absorptiometry in diagnosing osteoporosis

Although peripheral dual-energy X-ray absorptiometry measurements have been found to predict fractures in population studies of white subjects, little is known about their utility in other races and in patients with greater risk of fracture. In a cross-sectional study of 874 women referred for bone mineral density (BMD) testing, we examined the utility of heel BMD in African-American (AA) compared with Caucasian (CA) women and in women using glucocorticoids. The ability of heel T-score to predict central osteoporosis was similar in AA and CA women (odds ratio [OR] per 1 unit decrease in T-score of 2.79 [95% confidence interval {CI} 2.16-3.60] and 3.15 [95% CI 2.53-3.92], respectively). The association between heel T-score and prevalent vertebral fractures was also similar in the 2 groups (OR 1.46 [95% CI 1.15-1.85] in AA and 1.42 [95% CI 1.16-1.74] in CA). In women using glucocorticoids heel T-score was better than central T-score in predicting vertebral fractures (OR 1.38 [95% CI 1.03-1.85] and 1.22 [95% CI 0.86-1.73], respectively). We conclude that in a multiracial referral population heel BMD predicts central osteoporosis and prevalent vertebral fractures equally well in AA as in CA women and may be better than central BMD in assessing fragility in glucocorticoid users.

Comparison between various fracture risk assessment tools

The suboptimal performance of bone mineral density as the sole predictor of fracture risk and treatment decision making has led to the development of risk prediction algorithms that estimate fracture probability using multiple risk factors for fracture, such as demographic and physical characteristics, personal and family history, other health conditions, and medication use. We review theoretical aspects for developing and validating risk assessment tools, and illustrate how these principles apply to the best studied fracture probability tools: the World Health Organization FRAX®, the Garvan Fracture Risk Calculator, and the QResearch Database's QFractureScores. Model development should follow a systematic and rigorous methodology around variable selection, model fit evaluation, performance evaluation, and internal and external validation. Consideration must always be given to how risk prediction tools are integrated into clinical practice guidelines to support better clinical decision making and improved patient outcomes. Accurate fracture risk assessment can guide clinicians and individuals in understanding the risk of having an osteoporosis-related fracture and inform their decision making to mitigate these risks.

Skeletal structure in postmenopausal women with osteopenia and fractures is characterized by abnormal trabecular plates and cortical thinning

The majority of fragility fractures occur in women with osteopenia rather than osteoporosis as determined by dual‐energy X‐ray absorptiometry (DXA). However, it is difficult to identify which women with osteopenia are at greatest risk. We performed this study to determine whether osteopenic women with and without fractures had differences in trabecular morphology and biomechanical properties of bone. We hypothesized that women with fractures would have fewer trabecular plates, less trabecular connectivity, and lower stiffness. We enrolled 117 postmenopausal women with osteopenia by DXA (mean age 66 years; 58 with fragility fractures and 59 nonfractured controls). All had areal bone mineral density (aBMD) measured by DXA. Trabecular and cortical volumetric bone mineral density (vBMD), trabecular microarchitecture, and cortical porosity were measured by high‐resolution peripheral computed tomography (HR‐pQCT) of the distal radius and tibia. HR‐pQCT scans were subjected to finite element analysis to estimate whole bone stiffness and individual trabecula segmentation (ITS) to evaluate trabecular type (as plate or rod), orientation, and connectivity.Groups had similar age, race, body mass index (BMI), and mean T‐scores. Fracture subjects had lower cortical and trabecular vBMD, thinner cortices, and thinner, more widely separated trabeculae. By ITS, fracture subjects had fewer trabecular plates, less axially aligned trabeculae, and less trabecular connectivity. Whole bone stiffness was lower in women with fractures. Cortical porosity did not differ. Differences in cortical bone were found at both sites, whereas trabecular differences were more pronounced at the radius.In summary, postmenopausal women with osteopenia and fractures had lower cortical and trabecular vBMD; thinner, more widely separated and rodlike trabecular structure; less trabecular connectivity; and lower whole bone stiffness compared with controls,despite similar aBMD by DXA. Our results suggest that in addition to trabecular and cortical bone loss, changes in plate and rod structure may be important mechanisms of fracture in postmenopausal women with osteopenia.

Comparison of hip fracture and osteoporosis medication prescription rates across Canadian provinces

The study explores osteoporosis medication prescribing across Canadian provinces and any impact on hip fracture rates. Despite a marked variation in the prescribing of such medication, there is no effect on the hip fracture rate in either gender or any age group, suggesting either poor targeting or lack of efficacy.

INTRODUCTION

Hip fractures are the most disabling and costly of osteoporotic fractures, and a reduction in the risk of hip fracture is an expectation of osteoporosis medications. In this study, we have compared the use of osteoporosis medication across Canadian provinces with the rate of hip fractures in the same regions.

METHODS

Three years of hip fracture data (2007-2009 inclusive) were obtained from the Canadian Institute for Health Information for all Canadian provinces excluding Quebec. Population information was obtained from Statistics Canada and medication information from the Brogan Inc. database. Because osteoporosis medication is available daily, weekly, monthly, and yearly, medication prescriptions were converted to "units" of prescribing, so that a once a year infusion represented 365 units, a monthly prescription 30 units, and so forth.

RESULTS

There is a fourfold difference in prescribing across provinces but no corresponding variation in hip fracture rate. No significant correlation exists between prescribing load and hip fracture rate. This was true for all age groups, both genders, and for both intertrochanteric and subcapital hip fracture.

CONCLUSIONS

We find no association between osteoporosis medication prescribing and hip fracture rate. Possible explanations include insufficient numbers of at-risk patients on treatment, inappropriate targeting, and either lack of efficacy or efficacy limited to only certain subgroups of patients such as those with demonstrable trabecular osteoporosis.

FRAX®: prediction of major osteoporotic fractures in women from the general population: the OPUS study

Purposes

The aim of this study was to analyse how well FRAX® predicts the risk of major osteoporotic and vertebral fractures over 6 years in postmenopausal women from general population.

Patients and methods

The OPUS study was conducted in European women aged above 55 years, recruited in 5 centers from random population samples and followed over 6 years. The population for this study consisted of 1748 women (mean age 74.2 years) with information on incident fractures. 742 (43.1%) had a prevalent fracture; 769 (44%) and 155 (8.9%) of them received an antiosteoporotic treatment before and during the study respectively. We compared FRAX® performance with and without bone mineral density (BMD) using receiver operator characteristic (ROC) c-statistical analysis with ORs and areas under receiver operating characteristics curves (AUCs) and net reclassification improvement (NRI).

Results

85 (4.9%) patients had incident major fractures over 6 years. FRAX® with and without BMD predicted these fractures with an AUC of 0.66 and 0.62 respectively. The AUC were 0.60, 0.66, 0.69 for history of low trauma fracture alone, age and femoral neck (FN) BMD and combination of the 3 clinical risk factors, respectively. FRAX® with and without BMD predicted incident radiographic vertebral fracture (n = 65) with an AUC of 0.67 and 0.65 respectively. NRI analysis showed a significant improvement in risk assignment when BMD is added to FRAX®.

Conclusions

This study shows that FRAX® with BMD and to a lesser extent also without FN BMD predict major osteoporotic and vertebral fractures in the general population.

Screening postmenopausal women for fall and fracture prevention

Fragility fracture prevention has been historically associated with the diagnosis and treatment of osteoporosis. Given that the strongest determinant of fracture is falls, it is critical to add fall risk into clinical decision-making guidelines for fracture prevention. This special interest paper proposes an algorithm based on 2 validated tools: (1) World Health Organization's Fracture Risk Assessment Tool, which evaluates probability of fracture and (2) Functional Gait Assessment, which evaluates fall risk. Physical therapists can use this algorithm to better identify patients at greatest risk for fracture in order to customize interventions designed to promote bone health, minimize falls, and ultimately prevent fractures. Recommendations for referral, patient education, and exercise are provided for categories of varying fall and fracture risk.