A framework for the development of guidelines for the management of glucocorticoid-induced osteoporosis

Sclerostin antibody and interval treadmill training effects in a rodent model of glucocorticoid-induced osteopenia

Glucocorticoids have a beneficial anti-inflammatory and immunosuppressive effect, but their use is associated with decreased bone formation, bone mass and bone quality, resulting in an elevated fracture risk. Exercise and sclerostin antibody (Scl-Ab) administration have both been shown to increase bone formation and bone mass, therefore the ability of these treatments to inhibit glucocorticoid-induced osteopenia alone or in combination were assessed in a rodent model. Adult (4 months-old) male Wistar rats were allocated to a control group (C) or one of 4 groups injected subcutaneously with methylprednisolone (5mg/kg/day, 5 days/week). Methylprednisolone treated rats were injected subcutaneously 2 days/week with vehicle (M) or Scl-Ab-VI (M+S: 25mg/kg/day) and were submitted or not to treadmill interval training exercise (1h/day, 5 days/week) for 9 weeks (M+E, M+E+S). Methylprednisolone treatment increased % fat mass and % apoptotic osteocytes, reduced whole body and femoral bone mineral content (BMC), reduced femoral bone mineral density (BMD) and osteocyte lacunae occupancy. This effect was associated with lower trabecular bone volume (BV/TV) at the distal femur. Exercise increased BV/TV, osteocyte lacunae occupancy, while reducing fat mass, the bone resorption marker NTx, and osteocyte apoptosis. Exercise did not affect BMC or cortical microarchitectural parameters. Scl-Ab increased the bone formation marker osteocalcin and prevented the deleterious effects of M on bone mass, further increasing BMC, BMD and BV/TV to levels above the C group. Scl-Ab increased femoral cortical bone parameters at distal part and midshaft. Scl-Ab prevented the decrease in osteocyte lacunae occupancy and the increase in osteocyte apoptosis induced by M. The addition of exercise to Scl-Ab treatment did not result in additional improvements in bone mass or bone strength parameters. These data suggest that although our exercise regimen did prevent some of the bone deleterious effects of glucocorticoid treatment, particularly in trabecular bone volume and osteocyte apoptosis, Scl-Ab treatment resulted in marked improvements in bone mass across the skeleton and in osteocyte viability, resulting in decreased bone fragility.

Systemic lupus erythematosus, bone health, and osteoporosis

PURPOSE OF REVIEW

This manuscript will provide a review of recent publications, examining the correlation of systemic lupus erythematosus (SLE) with changes in bone health and associated osteoporosis, highlighting prevalence, etiology, diagnosis, and treatment.

RECENT FINDINGS

Studies suggest that bone loss and fractures are associated with SLE, related not only to the disease itself, but also with low vitamin D and treatment side-effects. Understanding the mechanisms of glucocorticoids on bone and the immunologic relationship of vitamin D, as well as recognizing the role of chronic inflammation on bone, allows for better understanding of skeletal side-effects. Further awareness of the association of poor bone health has led to an increased need for prevention and treatment. New imaging and treatment are emerging, although not recommended currently.

SUMMARY

Loss of bone density culminating in osteoporosis and fracture is a frequent comorbidity in SLE patients at any age and is multifactorial in etiology. Awareness and diagnosis is crucial because of its prevalence and morbidity. Prevention is safe and effective in this high-risk population where diagnostic measures and interventions are underutilized and guidelines are lacking.

Evaluating and mitigating fracture risk in established rheumatoid arthritis

Patients with rheumatoid arthritis are predisposed to systemic bone loss, and they are at an increased risk of fractures. Although there are similarities in the patient demographics between rheumatoid arthritis patients and the general population of osteoporosis patients, there are factors, particularly the use of glucocorticoids, which are specific to rheumatoid arthritis. These factors can lead to an increased risk of bone loss and fracture. Given that fractures are often very debilitating, especially in elderly patients, it is of paramount importance for the practicing rheumatologist to be aware of ways to reduce the risk of fracture in patients with rheumatoid arthritis. This review discusses currently available modalities for fracture risk assessment as well as pharmacologic and lifestyle interventions available to treat and prevent bone loss in rheumatoid arthritis patients.

FRAX and fracture prediction without bone mineral density

The major application of FRAX in osteoporosis is to direct pharmacological interventions to those at high risk of fracture. Whereas the efficacy of osteoporosis treatment, with the possible exception of alendronate, is largely independent of baseline bone mineral density (BMD), it remains a widely held perception that osteoporosis therapies are only effective in the presence of low BMD. Thus, the use of FRAX in the absence of BMD to identify individuals requiring therapy remains the subject of some debate and is the focus of this review. The clinical risk factors used in FRAX have high evidence-based validity to identify a risk responsive to intervention. The selection of high-risk individuals with FRAX, without knowledge of BMD, preferentially selects for low BMD and thus identifies a risk that is responsive to pharmacological intervention. The prediction of fractures with the use of clinical risk factors alone in FRAX is comparable to the use of BMD alone to predict fractures and is suitable, therefore, in the many countries where facilities for BMD testing are sparse. In countries where access to BMD is greater, FRAX can be used without BMD in the majority of cases and BMD tests reserved for those close to a probability-based intervention threshold. Thus concerns surrounding the use of FRAX in clinical practice without information on BMD are largely misplaced.

Drug-induced osteoporosis: from Fuller Albright to aromatase inhibitors

Many commonly prescribed medications, such as selective serotonin reuptake inhibitors, proton pump inhibitors, thiazolidinediones, aromatase inhibitors, and androgen deprivation therapy, have been associated with adverse skeletal effects. The levels of evidence in support of a causal relationship between drug use and the development of bone loss and fractures are variable. For some drugs, a causal relationship is suspected (but not proven) based on observational studies, while in others causality is firmly established with randomized, controlled clinical trials. The mechanism of action for skeletal damage is poorly understood for some drugs and well known for others. Guidelines for managing bone health in patients taking some medications with potential skeletal toxicity have been developed using the best available evidence and expert opinion. This is a review of selected medications that have been associated with bone loss and fractures, with recommendations for clinical care.

Use of anti-osteoporotic drugs in central Norway after a forearm fracture

Use of anti-osteoporotic drugs (AOD) the first year after a forearm fracture in central Norway was low in the period 2005-2012. Women with fractures used more AOD compared to the general population only in 2006, 2007, and 2011. Female gender, age ≥ 60 years, use of glucocorticosteroids, or ≥ 4 different drugs were associated with AOD use.

PURPOSE

The primary aim of this study was to examine time trends in prevalence and incidence of AOD use the first year after a forearm fracture from 2005-2012. Further, secondary aims were to investigate if gender, the number of drugs used before fracture, or use of glucocorticoids influenced the prescription of AOD, and to examine adherence to AOD.

METHODS

Data is from the fracture registry in Nord-Trøndelag and the Norwegian Prescription database, including women (N = 1434) and men (N = 513) 40-84 years with their first forearm fracture between 2005 and 2012. AOD were defined as bisphosphonates, teriparatide, denosumab, and raloxifene. Prevalence and incidence were calculated, and prevalent use among women with forearm fracture was compared with the population in Nord-Trøndelag and Norway. Age-adjusted Poisson regression analyses for time trends and odds ratio for treatment with AOD was estimated. Adherence was defined as medication possession ratio ≥ 80 %.

RESULTS

The first year after the fracture, 11.2 % of the women and 2.7 % of the men were prevalent users, while 5.1 % and 1.2 %, respectively, were incident users of AOD. Bisphosphonates comprised 98.8 %. AOD use among women with fractures was significantly higher compared to the general population in Nord-Trøndelag only in 2006, 2007, and 2011. There was a trend towards a decline in AOD use among women with fractures from 2005 to 2012 (coefficient -0.05, p = 0.15). Female gender, age ≥ 60 years, use of glucocorticosteroids, or ≥ 4 different drugs the last year before fracture were associated with AOD use. In women, 54.8 % were adherent during 3 years after fracture.

CONCLUSIONS

The use of AOD after a forearm fracture was low. An increased focus on osteoporosis in fracture patients is needed for secondary fracture prevention.

Management of endocrine disease: Secondary osteoporosis: pathophysiology and management

Osteoporosis is a skeletal disorder characterized by decreased mass and compromised bone strength predisposing to an increased risk of fractures. Although idiopathic osteoporosis is the most common form of osteoporosis, secondary factors may contribute to the bone loss and increased fracture risk in patients presenting with fragility fractures or osteoporosis. Several medical conditions and medications significantly increase the risk for bone loss and skeletal fragility. This review focuses on some of the common causes of osteoporosis, addressing the underlying mechanisms, diagnostic approach and treatment of low bone mass in the presence of these conditions.

Burden of high fracture probability worldwide: secular increases 2010-2040

The number of individuals aged 50 years or more at high risk of osteoporotic fracture worldwide in 2010 was estimated at 158 million and is set to double by 2040.

INTRODUCTION

The aim of this study was to quantify the number of individuals worldwide aged 50 years or more at high risk of osteoporotic fracture in 2010 and 2040.

METHODS

A threshold of high fracture probability was set at the age-specific 10-year probability of a major fracture (clinical vertebral, forearm, humeral or hip fracture) which was equivalent to that of a woman with a BMI of 24 kg/m(2) and a prior fragility fracture but no other clinical risk factors. The prevalence of high risk was determined worldwide and by continent using all available country-specific FRAX models and applied the population demography for each country.

RESULTS

Twenty-one million men and 137 million women had a fracture probability at or above the threshold in the world for the year 2010. The greatest number of men and women at high risk were from Asia (55 %). Worldwide, the number of high-risk individuals is expected to double over the next 40 years.

CONCLUSION

We conclude that individuals with high probability of osteoporotic fractures comprise a very significant disease burden to society, particularly in Asia, and that this burden is set to increase markedly in the future. These analyses provide a platform for the evaluation of risk assessment and intervention strategies.

Bone Tissue Properties Measurement by Reference Point Indentation in Glucocorticoid-Induced Osteoporosis

Glucocorticoids, widely used in inflammatory disorders, rapidly increase bone fragility and, therefore, fracture risk. However, common bone densitometry measurements are not sensitive enough to detect these changes. Moreover, densitometry only partially recognizes treatment-induced fracture reductions in osteoporosis. Here, we tested whether the reference point indentation technique could detect bone tissue property changes early after glucocorticoid treatment initiation. After initial laboratory and bone density measurements, patients were allocated into groups receiving calcium + vitamin D (Ca+D) supplements or anti-osteoporotic drugs (risedronate, denosumab, teriparatide). Reference point indentation was performed on the cortical bone layer of the tibia by a handheld device measuring bone material strength index (BMSi). Bone mineral density was measured by dual-energy X-ray absorptiometry (DXA). Although Ca+D-treated patients exhibited substantial and significant deterioration, risedronate-treated patients exhibited no significant change, and both denosumab- and teriparatide-treated participants exhibited significantly improved BMSi 7 weeks after initial treatment compared with baseline; these trends remained stable for 20 weeks. In contrast, no densitometry changes were observed during this study period. In conclusion, our study is the first to our knowledge to demonstrate that reference point indentation is sensitive enough to reflect changes in cortical bone indentation after treatment with osteoporosis therapies in patients newly exposed to glucocorticoids.

FRAX-based assessment and intervention thresholds--an exploration of thresholds in women aged 50 years and older in the UK

Under current guidelines, based on prior fracture probability thresholds, inequalities in access to therapy arise especially at older ages (≥70 years) depending on the presence or absence of a prior fracture. An alternative threshold (a fixed threshold from the age of 70 years) reduces this disparity, increases treatment access and decreases the need for bone densitometry.

INTRODUCTION

Several international guidelines set age-specific intervention thresholds at the 10-year probability of fracture equivalent to a woman of average BMI with a prior fracture. At older ages (≥70 years), women with prior fracture selected for treatment are at lower average absolute risk than those selected for treatment in the absence of prior fracture, prompting consideration of alternative thresholds in this age group.

METHODS

Using a simulated population of 50,633 women aged 50-90 years in the UK, with a distribution of risk factors similar to that in the European FRAX derivation cohorts and a UK-matched age distribution, the current NOGG intervention and assessment thresholds were compared to one where the thresholds remained constant from 70 years upwards.

RESULTS

Under current thresholds, 45.1% of women aged ≥70 years would be eligible for therapy, comprising 37.5% with prior fracture, 2.2% with high risk but no prior fracture and 5.4% selected for treatment after bone mineral density (BMD) measurement. Mean hip fracture probability was 11.3, 23.3 and 17.6%, respectively, in these groups. Under the alternative thresholds, the overall proportion of women treated increased from 45.1 to 52.9%, with 8.4% at high risk but no prior fracture and 7.0% selected for treatment after BMD measurement. In the latter group, the mean probability of hip fracture was identical to that observed in women with prior fracture (11.3%). The alternative threshold also reduced the need for BMD measurement, particularly at older ages (>80 years).

CONCLUSIONS

The alternative thresholds equilibrate fracture risk, particularly hip fracture risk, in those with or without prior fracture selected for treatment and reduce BMD usage at older ages.

Bisphosphonates in the treatment of glucocorticoid-induced osteoporosis: pros

In glucocorticoid-induced osteoporosis (GIO), both bone formation and resorption are altered, however, with a relative prevalence of resorption, consistent with the positive results that have been reported with bisphosphonate treatment. Many studies have investigated the effect of bisphosphonates (BPs), a widely used class of anti-resorptive drugs, showing a positive effect on bone mineral density and fracture risk. Also in case of postmenopausal osteoporosis, the safety and cost-effectiveness profile of BPs in GIO appears good. Currently, the use of BPs is recommended at the earliest by all major scientific societies in postmenopausal women and men ≥50 years at high risk of fracture receiving glucocorticoid therapy. BPs are the most commonly used anti-osteoporotic agents and they remain the current standard of care for GIO.

Treatment of Cushing's Syndrome: An Endocrine Society Clinical Practice Guideline

OBJECTIVE

The objective is to formulate clinical practice guidelines for treating Cushing's syndrome.

PARTICIPANTS

Participants include an Endocrine Society-appointed Task Force of experts, a methodologist, and a medical writer. The European Society for Endocrinology co-sponsored the guideline.

EVIDENCE

The Task Force used the Grading of Recommendations, Assessment, Development, and Evaluation system to describe the strength of recommendations and the quality of evidence. The Task Force commissioned three systematic reviews and used the best available evidence from other published systematic reviews and individual studies.

CONSENSUS PROCESS

The Task Force achieved consensus through one group meeting, several conference calls, and numerous e-mail communications. Committees and members of The Endocrine Society and the European Society of Endocrinology reviewed and commented on preliminary drafts of these guidelines.

CONCLUSIONS

Treatment of Cushing's syndrome is essential to reduce mortality and associated comorbidities. Effective treatment includes the normalization of cortisol levels or action. It also includes the normalization of comorbidities via directly treating the cause of Cushing's syndrome and by adjunctive treatments (eg, antihypertensives). Surgical resection of the causal lesion(s) is generally the first-line approach. The choice of second-line treatments, including medication, bilateral adrenalectomy, and radiation therapy (for corticotrope tumors), must be individualized to each patient.

2014 update of recommendations on the prevention and treatment of glucocorticoid-induced osteoporosis

OBJECTIVES

To update the recommendations on the prevention and treatment of glucocorticoid-induced osteoporosis issued in 2003 by the French National Authority for Health (HAS). This update was performed under the aegis of the Bone Section of the French Society for Rheumatology (SFR) and Osteoporosis Research and Information Group (GRIO), in collaboration with four French learned societies (primary-care, gastroenterology, internal medicine, and nephrology).

METHODS

A task force composed of members of the medical specialties involved in managing patients with glucocorticoid-induced osteoporosis conducted a systematic literature review according to the method developed by the HAS then used the results to develop updated recommendations.

RESULTS

These recommendations are intended for all physicians involved in the management of patients who are scheduled to start, or are taking, long-term glucocorticoid therapy (≥ 3 months) in any dose and for any reason. In postmenopausal women and men older than 50 years of age, treatment is warranted in the presence of any of the following risk factors for fracture: history of bone frailty fracture after 50 years of age, bone mineral density T-score ≤ −2.5 at one or more sites, age ≥ 70 years, and dosage ≥ 7.5 mg/d prednisone-equivalent for longer than 3 months. Bisphosphonates can be used in all these situations; teriparatide can be given as first-line therapy in patients at high fracture risk but is reimbursed by the French statutory health insurance system only in patients having two or more prevalent vertebral fractures. The fracture risk is lower in non-menopausal women and in men younger than 50 years of age,in whom treatment decisions should rest on a case-by-case evaluation.

CONCLUSION

These recommendations are intended to clarify the pharmacological management of glucocorticoid-induced osteoporosis.

The impact of glucocorticoid therapy on trabecular bone score in older women

We propose that trabecular bone score could be a useful tool for the study of glucocorticoid-associated bone effects. Trabecular bone score alone and lumbar spine bone mineral density (BMD) used in combination with trabecular bone score, but not lumbar spine BMD alone was able to discriminate between glucocorticoid-treated and glucocorticoid-naïve women.

INTRODUCTION

Glucocorticoids result in rapid bone loss and an increase in fracture risk that cannot be fully explained by changes in BMD. Trabecular bone score (TBS) correlates with three-dimensional bone micro-architectural parameters and can be derived from grey-level variations within dual energy X-ray absorptiometry (DXA) scans. We propose that TBS could be a useful tool for the study of glucocorticoid-associated bone effects.

METHODS

We assessed the ability of lumbar spine BMD (LS-BMD), TBS, and LS-BMD with TBS (LS-BMD + TBS) to discriminate between healthy women and (i) glucocorticoid-treated women, and (ii) glucocorticoid-naïve women with recent fractures. Older women (n = 484, ages 55-79 years) who had (i) taken prednisolone ≥5 mg/day for >3 months (n = 64), (ii) sustained a recent fracture of the distal forearm (n = 46), proximal humerus (n = 37), vertebra (n = 30) or proximal femur (n = 28), or (iii) were healthy population-based women (n = 279) were recruited. LS-BMD was measured by DXA and TBS values were derived.

RESULTS

Compared to healthy, population-based women, women with recent fractures had lower LS-BMD (-0.34 to -1.38) and TBS (-0.38 to -1.04) Z-scores. Glucocorticoid-treated women had lower TBS Z-scores than glucocorticoid-naïve women (-0.80 versus 0) but their LS-BMD Z-scores did not differ (-0.13 versus 0). TBS alone (area under the receiver operating characteristic curve (AUC) = 0.721) and LS-BMD + TBS (AUC = 0.721), but not LS-BMD alone (AUC = 0.572) was able to discriminate between glucocorticoid-treated and glucocorticoid-naïve women.

CONCLUSIONS

TBS provides additional information regarding glucocorticoid-associated alterations in bone quality. We conclude that TBS may be a useful tool for the further study of glucocorticoid-induced osteoporosis.

Management of glucocorticoid-induced osteoporosis: clinical data in relation to disease demographics, bone mineral density and fracture risk

INTRODUCTION

Glucocorticoid-induced osteoporosis (GIOP) is the most common type of secondary osteoporosis. Patient selection and the treatment choice remain to be controversial. None of the proposed management guidelines are widely accepted. We evaluate the available clinical data, the efficacy of current medication and we propose an overall algorithm for managing GIOP.

AREAS COVERED

This article provides a critical review of in vivo and clinical evidence regarding GIOP and developing evidence-based algorithm of treatment. Data base used includes MEDLINE® (1950 to May 2014).

EXPERT OPINION

Patient-specific treatment is the gold standard of care. Glucocorticoid (GC)-treated patients must comply with a healthy lifestyle and receive 1000 mg of calcium and at least 800 mg of Vitamin D daily. Bisphosphonate (BP) therapy is the current standard of care for prevention and treatment of GIOP. Most of bisphosphonates demonstrated benefit in lumbar bone mineral density (BMD) and some in hip BMD. Alendronate, risedronate and zoledronate showed vertebral anti-fracture efficacy in postmenopausal women and men. Scarce data however when compared head to head with BP efficacy. In post-menopausal women, early antiresorptive BP treatment appears to be efficient and safe. In premenopausal women and patients at high risk of fracture receiving long-term GC therapy however, teriparitide may be advised alternatively.

Fracture rate associated with quality metric-based anti-osteoporosis treatment in glucocorticoid-induced osteoporosis

Anti-osteoporosis medication (AOM) use in patients exposed to glucocorticoids is thought to reduce fractures. We found post-menopausal women using glucocorticoids for at least 90 days who also used an AOM within 90 days had 48 % fewer fractures by 1 year and 32 % fewer fractures by 3 years compared to non-AOM users.

INTRODUCTION

The purpose of this study is to explore the effectiveness of adherence to quality measures by estimating the effect of anti-osteoporosis medication (AOM) initiation within 90 days after chronic (≥90 days) glucocorticoid (GC) therapy on osteoporotic fracture.

METHODS

A new-user cohort was assembled using the MarketScan databases between 2000 and 2012. Included patients were female, age ≥50 at GC initiation, had a first GC fill daily dose ≥10 mg and persisted for at least 90 days. During a 365-day baseline period, patients were excluded for prior GC or AOM (bisphosphonate, denosumab, teriparatide) use, fracture, or cancer diagnosis. Initiators of an AOM in the 14 days pre- or 90 days post-GC fill were characterized as AOM users; those without, AOM non-users. Follow-up began 91 days after GC fill with patients followed until fracture, loss of continuous enrollment, initiation of AOM by AOM non-users, or end of study period. A propensity score was estimated for AOM receipt using all measured covariates and converted to a stabilized inverse probability of treatment weights (IPTW). Weighted hazard ratios (HR) and associated 95% confidence intervals (95% CI) were estimated using weighted Cox proportional hazard models.

RESULTS

Of the 7885 women eligible for the study, 12.1% were AOM users. AOM use was associated with lower fracture incidence: weighted HR of 0.52 (95% CI 0.29, 0.94) at 1 year and weighted HR of 0.68 (95% CI 0.47, 0.99) at 3 years.

CONCLUSIONS

AOM initiation within 90 days of chronic GC use was associated with a fracture reduction of 48% at 1 year and 32% at 3 years.

Glucocorticoid-induced osteoporosis

Corticosteroid-induced osteoporosis is the most common form of secondary osteoporosis and the first cause in young people. Bone loss and increased rate of fractures occur early after the initiation of corticosteroid therapy, and are then related to dosage and treatment duration. The increase in fracture risk is not fully assessed by bone mineral density measurements, as it is also related to alteration of bone quality and increased risk of falls. In patients with rheumatoid arthritis, a treat-to-target strategy focusing on low disease activity including through the use of low dose of prednisone, is a key determinant of bone loss prevention. Bone loss magnitude is variable and there is no clearly identified predictor of the individual risk of fracture. Prevention or treatment of osteoporosis should be considered in all patients who receive prednisone. Bisphosphonates and the anabolic agent parathyroid hormone (1-34) have shown their efficacy in the treatment of corticosteroid-induced osteoporosis. Recent international guidelines are available and should guide management of corticosteroid-induced osteoporosis, which remains under-diagnosed and under-treated. Duration of antiosteoporotic treatment should be discussed at the individual level, depending on the subject's characteristics and on the underlying inflammation evolution.

Local renin-angiotensin system is associated with bone mineral density of glucocorticoid-induced osteoporosis patients

The local renin-angiotensin system (RAS) is closely related to bone metabolism. However, it is unknown whether the local RAS is related to bone mineral density (BMD) in glucocorticoid-induced osteoporosis (GIOP). Here, we revealed that the two main characteristics of GIOP might inhibit bone formation and enhance bone resorption.

INTRODUCTION

The aim of this study is to assess the expression of the main RAS components in the trabecular bone of lumbar vertebrae in GIOP and analyze the relationship between the major RAS components and BMD.

METHODS

We collected 96 inpatient cases of lumbar disc herniation from patients who underwent dual-energy X-ray absorptiometry examinations followed by surgical treatment in our hospital. Patients were divided into the GIOP group (n = 48) and control group (n = 48). The circulating and local expression levels of the main RAS components were examined. The correlation between the main RAS components and BMD was then analyzed.

RESULTS

The mRNA expression of local bone angiotensin type 1 and 2 receptors (AT1R and AT2R, respectively) and RANKL was higher in the GIOP group compared with the control group (p < 0.001), but there was no difference in the circulating protein levels between groups (p > 0.05). Multiple logistic regression analysis revealed that AT1R and AT2R expression and the RANKL/OPG ratio in local bone were negatively associated with BMD (p < 0.001, odds ratio (OR) 1.236, 95 % confidence interval (CI) 1.207-1.333; p < 0.001, OR 1.971, 95% CI 1.809-2.233; and p < 0.001, OR 1.676, 95% CI 1.546-1.845, respectively).

CONCLUSION

This study provides evidence that the role of local RAS is related to BMD in GIOP patients, and suggests that local RAS might influence RANKL/OPG signaling to modulate bone metabolism.

Fragility fracture: recent developments in risk assessment

More than half of older women who sustain a fragility fracture do not have osteoporosis by World Health Organization (WHO) bone mineral density (BMD) criteria; and, while BMD has been used to assess fracture risk for over 30 years, a range of other skeletal and nonskeletal clinical risk factors (CRFs) for fracture have been recognized. More than 30 assessment tools using CRFs have been developed, some predicting fracture risk and others low BMD alone. Recent systematic reviews have reported that many tools have not been validated against fracture incidence, and that the complexity of tools and the number of CRFs included do not ensure best performance with poor assessment of (internal or comparative) validity. Internationally, FRAX® is the most commonly recommended tool, in addition to QFracture in the UK, The Canadian Association of Radiologists and Osteoporosis Canada (CAROC) tool in Canada and Garvan in Australia. All tools estimate standard 10-year risk of major osteoporotic and 10-year risk of hip fracture: FRAX® is able to estimate fracture risk either with or without BMD, but CAROC and Garvan both require BMD and QFracture does not. The best evidence for the utility of these tools is in case finding but there may be future prospects for the use of 10-year fracture risk as a common currency with reference to the benefits of treatment, whether pharmacological or lifestyle. The use of this metric is important in supporting health economic analyses. However, further calibration studies will be needed to prove that the tools are robust and that their estimates can be used in supporting treatment decisions, independent of BMD.

Lower P1NP serum levels: a predictive marker of bone loss after 1 year follow-up in premenopausal systemic lupus erythematosus patients

SUMMARY

Predictors of bone mineral density (BMD) loss are additional tools in the management of osteoporosis in premenopausal women with systemic lupus erythematosus (SLE). This study provides original evidence that N-terminal propeptide of type 1 collagen (P1NP), the most specific bone formation marker, is a predictor of BMD loss in this group of women.

INTRODUCTION

SLE is associated with a high risk of low bone mass/fractures but this risk is still controversial in premenopausal women. Our aim was to determine the 1 year incidence of BMD loss in premenopausal SLE women and the value of bone turnover markers as predictors of this complication.

METHODS

This study enrolled a convenience sample of 63 premenopausal SLE patients. BMD was evaluated by dual X-ray absorptiometry at lumbar spine and hip at baseline and after 12 months. BMD changes above the least significant change were considered significant. Serum levels of P1NP and CTX (electrochemiluminescence), OPG, and RANKL (ELISA) were determined at baseline.

RESULTS

Mean age was 31.1±6.8 years, and disease duration was 5.25±3.8 years. 36.5 % of patients presented BMD loss and 17.5 % BMD gain at lumbar spine and/or hip. Patients were divided in three groups: BMD loss (BL), no BMD change (NC), and BMD gain (BG). Patients with BL and NC received similar cumulative/mean/maximum glucocorticoid doses during the study, but patients with BG received lower doses (p<0.05). Baseline P1NP levels were different in the groups (BL: 36.95±23.37 vs. NC: 54.63±30.82 vs. BG: 84.09±43.85 ng/mL; p=0.031 BL vs. NC, p<0.001 BL vs. BG, and p=0.039 NC vs. BG). There was no difference in CTX, OPG, or RANKL levels. After multivariate analysis, P1NP remained as an independent risk factor for BMD loss (p<0.03).

CONCLUSIONS

This study provides original evidence that lower levels of P1NP, the most specific bone formation marker, are predictive of BMD loss over 12 months in premenopausal SLE patients.

United States adults meeting 2010 American College of Rheumatology criteria for treatment and prevention of glucocorticoid-induced osteoporosis

OBJECTIVE

The American College of Rheumatology (ACR) updated its guidelines on the prevention and treatment of glucocorticoid-induced osteoporosis (GIO) in 2010. An unknown proportion of US adults at risk of fracture due to glucocorticoid use would be recommended antiosteoporosis pharmaceutical (AOP) therapies based on the ACR guidelines.

METHODS

Using the 2005-2010 National Health and Nutrition Examination Survey (NHANES) data for postmenopausal women (PMW), and men age ≥50 years reporting current glucocorticoid use, we categorized individuals according to ACR criteria for low, medium, and high fracture risk (<10%, ≥10%, and ≥20%, respectively) and provided percentages of treatment recommendations for chronic (≥90 days) medium and all high-risk patients.

RESULTS

Glucocorticoids were used by 1.66% of PMW and 1.65% of men age ≥50 years. Of these patients, 0.80% of PMW and 0.45% of men age ≥50 years were at high risk of fracture. A majority of PMW (81.2%) and men age ≥50 years (75.8%) were chronic glucocorticoid users. In patients for whom treatment recommendations could be made, 64.9% of PMW and 51.9% of men age ≥50 years would be recommended therapy, but only 28.4% of PMW and 9.7% of men age ≥50 years reported AOP use.

CONCLUSION

Based on the NHANES (2005-2010) data, we estimate glucocorticoid use in >1.5 million US PMW and men age ≥50 years. Treatment would be recommended in at least 50% of this population based on the 2010 ACR guidelines. Self-reported AOP use was documented in <30%, suggesting a treatment gap in the management of GIO in the US before the guideline release.

Established and forthcoming drugs for the treatment of osteoporosis

PURPOSE OF REVIEW

The aim of treatment in patients at high risk for fractures is to reduce the risk of a first or a subsequent fracture. New data are available on the antifracture effects and side-effects of antiresorptive and osteoanabolic drugs, and new emerging therapies with new modes of action are on the horizon.

RECENT FINDINGS

Calcium and vitamin D intake should be sufficient, but not too high. Vertebral, nonvertebral (including hip fracture) prevention with antiresorptive drugs such as bisphosphonates (alendronate, risedronate and zoledronic acid) and denosumab exceeds the risk of rare side-effects such as atypical femur fracture and osteonecrosis of the jaw. Teriparatide is an osteoanabolic drug that improves quality of life in severe osteoporosis. Strontium ranelate decreases dynamic parameters of bone formation during the first year of treatment, and could increase the risk of cardiovascular events in high-risk patients. Initiation of and adherence to fracture prevention drugs are still low. New potential developments in antiresorptive drugs include odanacatib, a selective inhibitor of cathepsin K, and, in osteoanabolic drugs, monoclonal antibodies against sclerostin.

SUMMARY

These recent data indicate that fracture prevention with antiresorptives and teriparatide is effective with a reasonable safety profile. Odanacatib and antisclerostin are promising new drugs with new mechanisms of action, as they are able to disconnect the normal coupling between bone resorption and bone formation.

Managing osteoporosis with FRAX® in Australia: proposed new treatment thresholds from the 45&Up Study cohort

INTRODUCTION

Many people at high risk of fractures are not following traditional guidelines and not being recommended for intervention. This study aimed to propose and evaluate a new set of intervention thresholds.

METHODS

Participants were 213,375 men and women aged ≥50 years living in New South Wales, Australia. Fracture Risk Assessment Paper Charts (Australia) was used to estimate the 10-year fracture risk. The standardized rates (to Australia population distribution 2007) for intervention were calculated for different thresholds: our proposed new thresholds (i.e. 10-year probability of hip fracture: ≥3%, 5% or 7% for 50-69, 70-79 and ≥80 years respectively), thresholds by the National Osteoporosis Guideline Group (NOGG) approach, UK thresholds and US thresholds.

RESULTS

The NOGG, UK and US thresholds did not work well in the Australian population. For example, the NOGG and UK thresholds respectively qualified only 1 in 12 (8.1%) and 1 in 9 (11.3%) Australian men aged ≥70 years and the US thresholds qualified about 9 in 10 (90.6%) Australian women aged ≥ 70 years. For men or women aged ≥70 years, our proposed new thresholds gave more realistic treatment rates of 21.6% for men and 70.5% for women. Compared to the current Australian guidelines (i.e. T-score ≤ -2.5 and age ≥ 70 years or a fragility fracture), our thresholds identified an additional 4.9% of men and 18.2% of women aged ≥ 70 years for treatment.

CONCLUSION

The proposed new thresholds could identify currently under-recognised high-risk individuals for treatment. It should be considered as a recommendation for osteoporosis management in Australia.

The application of health technology assessment in osteoporosis

Because of the high costs to patients, health care payers and to society, it is important to allocate healthcare resources appropriately and efficiently. Health technology assessment aims to evaluate the clinical, economic, social, and ethical implications of a disease, and its prevention and treatment to guide national healthcare policies (e.g. clinical and research investment, reimbursement decisions). In this chapter, we review the various aspects of health technology assessment in osteoporosis, including epidemiology and burden of disease, and assessment of the cost-effectiveness of the treatment of osteoporosis and the prevention of fracture. Health technology assessment indicates an immense burden of osteoporotic fractures for patients and society that is set to increase as the number of elderly people increases. Prevention and treatment of osteoporosis have been shown to be a cost-effective way of allocating scarce healthcare resources.

Identification of patient profile for treatment

The WHO clinical definition of osteoporosis, based on a measurement of bone mineral density (BMD) by Dual Energy X-ray Absorptiometry, has been used globally since the mid-1990s. However, although this definition identifies those at greatest individual risk of fracture, in the population overall a greater total number of fractures occur in individuals with BMD values above the osteoporosis threshold. The inclusion of clinical risk factors, with or without BMD, in fracture prediction algorithms can improve the identification of individuals at high fracture risk; thus a number of web-based tools have been developed, the most commonly used globally being FRAX(®). In this review, we will discuss the epidemiology of osteoporosis, clinical risk factors for fragility fracture, and how this knowledge is being used to aid risk stratification. Importantly, research is on-going to demonstrate the clinical efficacy and cost-effectiveness of such case-finding strategies.

Glucocorticoid-induced osteoporosis: who to treat with what agent?

Among the adverse events of glucocorticoid treatment are bone loss and fractures. Despite available, effective preventive measures, many patients receiving or initiating glucocorticoid therapy are not appropriately evaluated and treated for bone health and fracture risk. Populations with, or at risk of, glucocorticoid-induced osteoporosis (GIOP) to target for these measures are defined on the basis of dose and duration of glucocorticoid therapy and bone mineral density. That patients with GIOP should be treated as early as possible is generally agreed upon; however, diversity remains in intervention thresholds and management guidelines. The FRAX(®) algorithm provides a 10-year probability of fracture that can be adjusted according to glucocorticoid dose. There is no evidence that GIOP and postmenopausal osteoporosis respond differently to treatments. Available anti-osteoporotic therapies such as anti-resorptives including bisphosphonates and the bone anabolic agent teriparatide are effective for the management of GIOP. Prevention with calcium and vitamin D supplementation is less effective than specific anti-osteoporotic treatment. Anti-osteoporotic treatment should be stopped at the time of glucocorticoid cessation, unless the patient remains at increased risk of fracture.

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.

Glucocorticoids activate the local renin-angiotensin system in bone: possible mechanism for glucocorticoid-induced osteoporosis

Bone metabolism disorder has been identified to play a vital role in the pathogenesis of glucocorticoid-induced osteoporosis (GIOP). The local renin-angiotensin system (RAS) in bone is newly defined to be closely related to the bone metabolism. However, it is unknown whether the local RAS is involved in GIOP. Adult male New Zealand white rabbits were treated with saline, dexamethasone (DXM) alone, or DXM combined with perindopril. The expression of main RAS components in trabecular bone was examined at mRNA and/or protein levels. Bone metabolism was analyzed using dual-energy X-ray absorptiometry, histomorphometry, biomechanics, biochemical techniques, and quantitative RT-PCR. The expressions of local bone angiotensin II, angiotensin types 1 and 2 receptors, and angiotensin-converting enzyme at mRNA and/or protein levels increased when DXM-induced osteoporosis was present. Whereas, perindopril significantly blocked the activation of the local RAS and partially reversed GIOP. Mineralizing surface, mineral apposition rate, and bone formation rate were decreased by DXM, along with serum osteocalcin being downregulated. These changes were then reversed by the use of perindopril. Osteoclast number, osteoclast surface, and eroded surface increased after the administration of DXM, and urinary deoxypyridinoline was upregulated. These were also inhibited when perindopril was given. Quantitative RT-PCR using RNA isolated from the lumbar vertebrae revealed an increase in the SOST expression and a decrease in the Runx2 expression, whereas the receptor activator of nuclear factor-κB ligand/osteoprotegerin ratio and the expression of tartrate resistant acid phosphatase were increased, which were all inhibited by perindopril. The results of this study provide evidence for the role of local RAS is involved in GIOP, and GIOP may be ameliorated by blocking the activation of local RAS in the bone.

Medication-induced osteoporosis: screening and treatment strategies

Drug-induced osteoporosis is a significant health problem and many physicians are unaware that many commonly prescribed medications contribute to significant bone loss and fractures. In addition to glucocorticoids, proton pump inhibitors, selective serotonin receptor inhibitors, thiazolidinediones, anticonvulsants, medroxyprogesterone acetate, aromatase inhibitors, androgen deprivation therapy, heparin, calcineurin inhibitors, and some chemotherapies have deleterious effects on bone health. Furthermore, many patients are treated with combinations of these medications, possibly compounding the harmful effects of these drugs. Increasing physician awareness of these side effects will allow for monitoring of bone health and therapeutic interventions to prevent or treat drug-induced osteoporosis.

Fracture risk assessment before and after resolution of endogenous hypercortisolism: is the FRAX® algorithm useful?

PURPOSE

Fracture risk data following curative treatment of Cushing's syndrome (CS) are scarce and the role of bisphosphonates in bone recovery after remission is controversial. We evaluated the effects of hypercortisolism remission in bone recovery in CS. Then, we assessed if the FRAX(®) algorithm calculated before the cure can predict fracture risk after cure.

METHODS

Thirty-six patients with CS were retrospectively investigated. Bone turnover markers, bone mineral density (BMD) at the lumbar spine (L1-L4) and left femur (both neck and total hip were considered), and fracture risk using FRAX(®) algorithm with femoral neck BMD were evaluated at diagnosis and after a median follow-up of 24 months (range 12-108 months) from hypercortisolism remission. Data about bone active therapy were analyzed.

RESULTS

Hypercortisolism remission was associated with the improvement of all densitometric parameters and with the reduction of fracture risk. The percentage change in BMD and the fracture risk were not significantly different in bisphosphonate-treated vs. untreated patients. During follow-up, three fractured patients at baseline exhibited a new vertebral fracture. A baseline 10-year probability of major osteoporotic fractures (FRAX(®) Major) of 17 % was able to predict the occurrence of a new vertebral fracture during follow-up after cure with 100 % sensitivity, 77 % specificity, 81 % positive predictive value and 100 % negative predictive value.

CONCLUSIONS

Osteoporosis and fracture risk may be reversible after curative treatment of CS, regardless of bisphosphonate therapy. We suggest applying the FRAX(®) algorithm to all active CS patients using a baseline FRAX(®) Major of 17 % as "intervention threshold".

A review of osteoporosis management in younger premenopausal women

The purpose of this review is to describe the available evidence for osteoporosis treatments in young and premenopausal women. A review of articles evaluating the treatment or prevention of osteoporosis in young (age less than 50 years) or premenopausal women was conducted. Several trials evaluating the treatment of anorexia nervosa and use of hormone therapy in those women, the use of bisphosphonates in women undergoing chemotherapy for breast cancer and the use of bisphosphonates, teriparatide and vitamin D in women with glucocorticoid-induced osteoporosis are described. Limited data were found to support the treatment of osteoporosis in women with idiopathic osteoporosis or cystic fibrosis, or after kidney transplant. The evidence for treatment of osteoporosis in premenopausal women is not nearly as robust as that for postmenopausal osteoporosis. Although fracture risk in the premenopausal population is low, women with secondary osteoporosis may benefit from treatment with various agents, depending upon the condition.

Study description and baseline characteristics of the population enrolled in a multinational observational study of extended teriparatide use (ExFOS)

OBJECTIVE

To better characterize patients who are currently being prescribed teriparatide in Europe, this article describes the study design and baseline characteristics of participants of the Extended Forsteo * Observational Study (ExFOS).

RESEARCH DESIGN AND METHODS

ExFOS is a noninterventional, multicenter, prospective, observational study in men and women with osteoporosis treated with teriparatide during the course of normal clinical practice for up to 24 months and with a post-treatment follow-up of at least 18 months.

MAIN OUTCOME MEASURES

Baseline characteristics, including history of fracture and back pain, and health-related quality of life (HRQoL, assessed using the EuroQol-5 Dimension [EQ-5D]).

RESULTS

Of 1607 patients enrolled, 90.9% were women. At baseline, mean (standard deviation [SD]) age was 70.3 (9.8) years, and 85.8% of patients had a history of fracture (64.7% with ≥2 fragility fractures). Of those with historic fractures, 90.8% had vertebral fractures (67.8% had thoracic fractures). The mean (SD) of reported bone mineral density T-scores were -3.0 (1.2), -2.4 (1.0), and -2.5 (0.9) for lumbar spine, total hip (left), and femoral neck (left), respectively. Overall, 39.3% of patients had experienced ≥1 fall during the 12 months before enrollment. At baseline, 11.4% of patients were osteoporosis-treatment naïve and 15% were currently using glucocorticoids. The mean (SD) visual analog scale score for back pain during the last month was 50.7 (26.9), and 62.1% of patients experienced daily or almost daily back pain. The median EQ-5D health state value at baseline was 0.62 (first and third quartiles: 0.19, 0.74).

CONCLUSIONS

Baseline characteristics of the ExFOS study cohort indicate that patients prescribed teriparatide in Europe have severe osteoporosis with highly prevalent vertebral fractures, frequent and disabling back pain, and a poor HRQoL, despite previous pharmacotherapy for osteoporosis. Limitations include non-randomization, lack of a comparator group, and patient self-report for data on prior medication and fracture history.

Psoriasis and bone mineral density: implications for long-term patients

Psoriasis is a chronic inflammatory disease associated with several comorbidities. Osteoporosis is defined as a reduction in bone mineral density with impaired bone microarchitecture. Several mechanisms may be implicated as a possible cause for the association between psoriasis and osteoporosis, such as systemic inflammation, anti-psoriatic drug intake and joint dysfunction for psoriatic arthritis (PsA). The aim of the present study was to assess bone mineral density (BMD) in patients with psoriasis, correlating the prevalence of osteopenia/osteoporosis with Psoriasis Area and Severity Index (PASI) score, mean duration of psoriatic disease, PsA and previous treatments for psoriasis. Forty-three consecutive patients with psoriasis, 19 of whom were affected by the arthropathic form, were enrolled. We evaluated the severity of psoriasis as measured by PASI score, the CASPAR criteria and ultrasounds of the joints to verify the diagnosis of PsA and the age of psoriasis onset to estimate mean disease duration. Patients underwent a bone density scan of the lumbar spine and femoral neck by dual-energy X-ray absorptiometry to measure BMD. Patients with osteopenia/osteoporosis showed a statistically significant longer average duration of psoriatic disease (17 years), compared to patients affected by psoriasis with normal T-score (8.8 years) (P = 0.04). The linear logistic regression confirms a significant relation between mean psoriatic disease duration and BMD alterations (P = 0.04). Our results suggest the necessity of an early diagnostic evaluation of bone metabolism in patients with psoriasis, especially if characterized by longer disease duration.

Bone safety of low-dose glucocorticoids in rheumatic diseases

Glucocorticoids are widely used internationally for the treatment of inflammatory disease, such as rheumatoid arthritis (RA). Although the benefit of glucocorticoids in RA on both disease activity and severity are well known, there remain unanswered questions about the overall bone safety of chronic low-dose glucocorticoids in RA. Debate exists about the merits of glucocorticoids for bone health on the basis of their benefits in promoting activity and reducing proinflammatory cytokines. Overall current evidence supports the view that bone loss is a disease related both to RA and to glucocorticoid use independently. Calcium and vitamin D, along with prescription antiosteoporosis therapies, particularly bisphosphonates and teriparatide, play an important role in stabilizing bone mineral density and potentially lowering spinal fracture risk at the spine. International guidelines provide pathways for appropriate prevention of glucocorticoid-induced osteoporosis (GIOP). Despite the evidence and these guidelines, many patients do not receive adequate management to prevent GIOP.

The relevance of biomaterials to the prevention and treatment of osteoporosis

Osteoporosis is a worldwide disease with a very high prevalence in humans older than 50. The main clinical consequences are bone fractures, which often lead to patient disability or even death. A number of commercial biomaterials are currently used to treat osteoporotic bone fractures, but most of these have not been specifically designed for that purpose. Many drug- or cell-loaded biomaterials have been proposed in research laboratories, but very few have received approval for commercial use. In order to analyze this scenario and propose alternatives to overcome it, the Spanish and European Network of Excellence for the Prevention and Treatment of Osteoporotic Fractures, "Ageing", was created. This network integrates three communities, e.g. clinicians, materials scientists and industrial advisors, tackling the same problem from three different points of view. Keeping in mind the premise "living longer, living better", this commentary is the result of the thoughts, proposals and conclusions obtained after one year working in the framework of this network.

Glucocorticoids and bone: local effects and systemic implications

Glucocorticoids (GCs) are highly effective in the treatment of inflammatory and autoimmune conditions but their therapeutic use is limited by numerous adverse effects. Recent insights into the mechanisms of action of both endogenous and exogenous GCs on bone cells have unlocked new approaches to the development of effective strategies for the prevention and treatment of GC-induced osteoporosis. Furthermore, topical studies in rodents indicate that the osteoblast-derived peptide, osteocalcin, plays a central role in the pathogenesis of GC-induced diabetes and obesity. These exciting findings mechanistically link the detrimental effects of GCs on bone and energy metabolism. In this article we review the physiology and pathophysiology of GC action on bone cells, and discuss current and emerging concepts regarding the molecular mechanisms underlying adverse effects of GCs such as osteoporosis and diabetes.

Treatment of skeletal impairment in patients with endogenous hypercortisolism: when and how?

Guidelines for the management of osteoporosis induced by endogenous hypercortisolism are not available. Both the American College of Rheumatology and the International Osteoporosis Foundation recommend to modulate the treatment of exogenous glucocorticoid-induced osteoporosis (GIO) based on the individual fracture risk profile (calculated by FRAX) and dose of glucocorticoid used, but it is difficult to translate corticosteroid dosages to different degrees of endogenous hypercortisolism, and there are no data on validation of FRAX stratification method in patients with endogenous hypercortisolism. Consequently, it is unclear whether such recommendations may be adapted to patients with endogenous hypercortisolism. Moreover, patients with exogenous GIO take glucocorticoids since suffering a disease that commonly affects bone. On the other hand, the correction of coexistent risk factors, which may contribute to increase the fracture risk in patients exposed to glucocorticoid excess, and the removal of the cause of endogenous hypercortisolism, may lead to the recovery of bone health. Although the correction of hypercortisolism and of possible coexistent risk factors is necessary to favor the normalization of bone turnover with recovery of bone mass; in some patients, the fracture risk could not be normalized and specific anti-osteoporotic drugs should be given. Who, when, and how the patient with endogenous hypercortisolism should be treated with bone-active therapy is discussed.

Worldwide uptake of FRAX

The worldwide uptake of FRAX is described.

INTRODUCTION

The aim of this report was to determine the usage of FRAX worldwide over a 1-year period from 1 May 2012.

METHODS

The number of FRAX calculations from each country was assessed over a 1-year period and expressed as calculations per million of the population aged 50 years or more. Countries were colour coded according to usage to populate a world map.

RESULTS

Over the index year, there were estimated to be 2,391,639 calculations sourced from 173 counties. Uptake was high in North America, the Antipodes and most countries of Europe; intermediate in Latin America and the Middle East; and very low in Africa and much of South East Asia.

CONCLUSIONS

It is expected that the comparative data will encourage the development of new FRAX models and the uptake of FRAX into assessment guidelines.