Fracture prediction from self-reported falls in routine clinical practice: a registry-based cohort study

Balancing fracture risk versus risk of mortality before fracture among women aged 80 years or older

BACKGROUND

Most fractures occur in women aged ≥80 years but competing mortality unrelated to fracture may limit the benefit of osteoporosis drug therapy for some women in late life. Our primary aim was to develop separate prediction models for non-spine fracture (NSF) and mortality before fracture to identify subsets of women with varying fracture versus mortality risks.

METHODS

Separate prediction models were developed for NSF and mortality before NSF for 4895 women aged ≥80 years enrolled in the Study of Osteoporotic Fractures (SOF) or the Health Aging and Body Composition (HABC) study. Proportional hazards models modified to account for competing mortality were used to identify candidate risk factors for each outcome. Predictors associated with NSF or mortality (p < 0.2) were included in separate competing risk models to estimate the cumulative incidence of NSF and mortality before NSF during 5 years of follow-up. This process was repeated to develop separate prediction models for hip fracture and mortality before hip fracture.

RESULTS

Significant predictors of NSF (race, total hip BMD, grip strength, prior fracture, falls, and use of selective serotonin reuptake inhibitors, benzodiazepines, or oral/transdermal estrogen) differed from predictors of mortality before NSF (age, walking speed, multimorbidity, weight change, shrinking, smoking, self-rated health, dementia, and use of warfarin). Within nine subsets of women defined by tertiles of risk, 5-year outcomes varied from 28% NSF and 8% mortality in the high-risk NSF/low-risk mortality subset, to 9% NSF and 22% mortality in the low-risk NSF/high-risk mortality subset. Similar results were seen for predictors of hip fracture and mortality before hip fracture.

CONCLUSION

Considerable variation in 5-year competing mortality risk is present among women in late life with similar 5-year NSF risk. Both fracture risk and life expectancy should inform shared clinical decision-making regarding initiation or continuation of osteoporosis drug therapy for women aged ≥80 years.

The association of FRAX with predictors of falls in the assessment of postmenopausal osteoporosis in Turkey: the fracture study of Turkey (FRACT study)

Although FRAX is used for fracture risk evaluation, this tool does not include balance and fall risk. The association between the predictors of falls and high FRAX scores we found in this study suggests that risk indicators for falls may add substantial value to FRAX by improving fracture risk prediction.

PURPOSE

This observational, descriptive, and cross-sectional study aimed to assess the fall risk predictors and explore their association with FRAX in Turkish patients with postmenopausal osteoporosis.

METHODS

Two hundred and nine (209) women with postmenopausal osteoporosis referred to the Fracture Liaison Service (FLS) at Istanbul University-Cerrahpaşa were enrolled in the FRACT study (The Fracture Study of Turkey). Clinical risk factors were assessed using the FRAX tool. Tandem stance, Tandem walking, Timed up and go (TUG), and Chair stand tests were performed to assess balance and fall risk.

RESULTS

Among patients with a mean age of 67.6 (± 9.7) years, 66 patients (31.6%) had osteoporosis without fractures and 143 patients (68.4%) had fragility fractures. The proportion of patients with poor performance of fall prediction tests was significantly higher in patients with a fragility fracture than those with osteoporosis alone. There was an inverse relationship between dynamic balance tests and the reported number of prior falls in the past year. FRAX score was higher in patients with impaired Tandem stance, Tandem walking, and TUG tests (p = 0.008, p = 0.035, p = 0.001, respectively).

CONCLUSION

Assessment of fall risk predictors should be one of the major pillars in the physical evaluation of osteoporotic patients in the FLS setting. FRAX is a useful tool to determine the fracture risk of patients with both static and dynamic balance impairments. Combining balance assessment with FRAX may be an important step to optimize osteoporosis risk assessment.

An overview of the use of the fracture risk assessment tool (FRAX) in osteoporosis

FRAX®, a simple-to-use fracture risk calculator, was first released in 2008 and since then has been used increasingly worldwide. By calculating the 10-year probabilities of a major osteoporotic fracture and hip fracture, it assists clinicians when deciding whether further investigation, for example a bone mineral density measurement (BMD), and/or treatment is needed to prevent future fractures. In this review, we explore the literature around osteoporosis and how FRAX has changed its management. We present the characteristics of this tool and describe the use of thresholds (diagnostic and therapeutic). We also present arguments as to why screening with FRAX should be considered. FRAX has several limitations which are described in this review. This review coincides with the release of a version, FRAXplus, which addresses some of these limitations.

A meta-analysis of previous falls and subsequent fracture risk in cohort studies

The relationship between self-reported falls and fracture risk was estimated in an international meta-analysis of individual-level data from 46 prospective cohorts. Previous falls were associated with an increased fracture risk in women and men and should be considered as an additional risk factor in the FRAX® algorithm.

INTRODUCTION

Previous falls are a well-documented risk factor for subsequent fracture but have not yet been incorporated into the FRAX algorithm. The aim of this study was to evaluate, in an international meta-analysis, the association between previous falls and subsequent fracture risk and its relation to sex, age, duration of follow-up, and bone mineral density (BMD).

METHODS

The resource comprised 906,359 women and men (66.9% female) from 46 prospective cohorts. Previous falls were uniformly defined as any fall occurring during the previous year in 43 cohorts; the remaining three cohorts had a different question construct. The association between previous falls and fracture risk (any clinical fracture, osteoporotic fracture, major osteoporotic fracture, and hip fracture) was examined using an extension of the Poisson regression model in each cohort and each sex, followed by random-effects meta-analyses of the weighted beta coefficients.

RESULTS

Falls in the past year were reported in 21.4% of individuals. During a follow-up of 9,102,207 person-years, 87,352 fractures occurred of which 19,509 were hip fractures. A previous fall was associated with a significantly increased risk of any clinical fracture both in women (hazard ratio (HR) 1.42, 95% confidence interval (CI) 1.33-1.51) and men (HR 1.53, 95% CI 1.41-1.67). The HRs were of similar magnitude for osteoporotic, major osteoporotic fracture, and hip fracture. Sex significantly modified the association between previous fall and fracture risk, with predictive values being higher in men than in women (e.g., for major osteoporotic fracture, HR 1.53 (95% CI 1.27-1.84) in men vs. HR 1.32 (95% CI 1.20-1.45) in women, P for interaction = 0.013). The HRs associated with previous falls decreased with age in women and with duration of follow-up in men and women for most fracture outcomes. There was no evidence of an interaction between falls and BMD for fracture risk. Subsequent risk for a major osteoporotic fracture increased with each additional previous fall in women and men.

CONCLUSIONS

A previous self-reported fall confers an increased risk of fracture that is largely independent of BMD. Previous falls should be considered as an additional risk factor in future iterations of FRAX to improve fracture risk prediction.

Follow-up Bone Mineral Density Testing: 2023 Official Positions of the International Society for Clinical Densitometry

Dual-energy X-ray absorptiometry (DXA) is the gold standard method for measuring bone mineral density (BMD) which is most strongly associated with fracture risk. BMD is therefore the basis for the World Health Organization's densitometric definition of osteoporosis. The International Society for Clinical Densitometry (ISCD) promotes best densitometry practices and its official positions reflect critical review of current evidence by domain experts. This document reports new official positions regarding follow-up DXA examinations based on a systematic review of literature published through December 2022. Adoption of official positions requires consensus agreement from an expert panel following a modified RAND protocol. Unless explicitly altered by the new position statements, prior ISCD official positions remain in force. This update reflects increased consideration of the clinical context prompting repeat examination. Follow-up DXA should be performed with pre-defined objectives when the results would have an impact on patient management. Testing intervals should be individualized according to the patient's age, sex, fracture risk and treatment history. Incident fractures and therapeutic approach are key considerations. Appropriately ordered and interpreted follow-up DXA examinations support diagnostic and therapeutic decision making, thereby contributing to excellent clinical care. Future research should address the complementary roles of clinical findings, imaging and laboratory testing to guide management.

Screening for the primary prevention of fragility fractures among adults aged 40 years and older in primary care: systematic reviews of the effects and acceptability of screening and treatment, and the accuracy of risk prediction tools

BACKGROUND

To inform recommendations by the Canadian Task Force on Preventive Health Care, we reviewed evidence on the benefits, harms, and acceptability of screening and treatment, and on the accuracy of risk prediction tools for the primary prevention of fragility fractures among adults aged 40 years and older in primary care.

METHODS

For screening effectiveness, accuracy of risk prediction tools, and treatment benefits, our search methods involved integrating studies published up to 2016 from an existing systematic review. Then, to locate more recent studies and any evidence relating to acceptability and treatment harms, we searched online databases (2016 to April 4, 2022 [screening] or to June 1, 2021 [predictive accuracy]; 1995 to June 1, 2021, for acceptability; 2016 to March 2, 2020, for treatment benefits; 2015 to June 24, 2020, for treatment harms), trial registries and gray literature, and hand-searched reviews, guidelines, and the included studies. Two reviewers selected studies, extracted results, and appraised risk of bias, with disagreements resolved by consensus or a third reviewer. The overview of reviews on treatment harms relied on one reviewer, with verification of data by another reviewer to correct errors and omissions. When appropriate, study results were pooled using random effects meta-analysis; otherwise, findings were described narratively. Evidence certainty was rated according to the GRADE approach.

RESULTS

We included 4 randomized controlled trials (RCTs) and 1 controlled clinical trial (CCT) for the benefits and harms of screening, 1 RCT for comparative benefits and harms of different screening strategies, 32 validation cohort studies for the calibration of risk prediction tools (26 of these reporting on the Fracture Risk Assessment Tool without [i.e., clinical FRAX], or with the inclusion of bone mineral density (BMD) results [i.e., FRAX + BMD]), 27 RCTs for the benefits of treatment, 10 systematic reviews for the harms of treatment, and 12 studies for the acceptability of screening or initiating treatment. In females aged 65 years and older who are willing to independently complete a mailed fracture risk questionnaire (referred to as "selected population"), 2-step screening using a risk assessment tool with or without measurement of BMD probably (moderate certainty) reduces the risk of hip fractures (3 RCTs and 1 CCT, n = 43,736, absolute risk reduction [ARD] = 6.2 fewer in 1000, 95% CI 9.0-2.8 fewer, number needed to screen [NNS] = 161) and clinical fragility fractures (3 RCTs, n = 42,009, ARD = 5.9 fewer in 1000, 95% CI 10.9-0.8 fewer, NNS = 169). It probably does not reduce all-cause mortality (2 RCTs and 1 CCT, n = 26,511, ARD = no difference in 1000, 95% CI 7.1 fewer to 5.3 more) and may (low certainty) not affect health-related quality of life. Benefits for fracture outcomes were not replicated in an offer-to-screen population where the rate of response to mailed screening questionnaires was low. For females aged 68-80 years, population screening may not reduce the risk of hip fractures (1 RCT, n = 34,229, ARD = 0.3 fewer in 1000, 95% CI 4.2 fewer to 3.9 more) or clinical fragility fractures (1 RCT, n = 34,229, ARD = 1.0 fewer in 1000, 95% CI 8.0 fewer to 6.0 more) over 5 years of follow-up. The evidence for serious adverse events among all patients and for all outcomes among males and younger females (<65 years) is very uncertain. We defined overdiagnosis as the identification of high risk in individuals who, if not screened, would never have known that they were at risk and would never have experienced a fragility fracture. This was not directly reported in any of the trials. Estimates using data available in the trials suggest that among "selected" females offered screening, 12% of those meeting age-specific treatment thresholds based on clinical FRAX 10-year hip fracture risk, and 19% of those meeting thresholds based on clinical FRAX 10-year major osteoporotic fracture risk, may be overdiagnosed as being at high risk of fracture. Of those identified as being at high clinical FRAX 10-year hip fracture risk and who were referred for BMD assessment, 24% may be overdiagnosed. One RCT (n = 9268) provided evidence comparing 1-step to 2-step screening among postmenopausal females, but the evidence from this trial was very uncertain. For the calibration of risk prediction tools, evidence from three Canadian studies (n = 67,611) without serious risk of bias concerns indicates that clinical FRAX-Canada may be well calibrated for the 10-year prediction of hip fractures (observed-to-expected fracture ratio [O:E] = 1.13, 95% CI 0.74-1.72, I² = 89.2%), and is probably well calibrated for the 10-year prediction of clinical fragility fractures (O:E = 1.10, 95% CI 1.01-1.20, I² = 50.4%), both leading to some underestimation of the observed risk. Data from these same studies (n = 61,156) showed that FRAX-Canada with BMD may perform poorly to estimate 10-year hip fracture risk (O:E = 1.31, 95% CI 0.91-2.13, I² = 92.7%), but is probably well calibrated for the 10-year prediction of clinical fragility fractures, with some underestimation of the observed risk (O:E 1.16, 95% CI 1.12-1.20, I² = 0%). The Canadian Association of Radiologists and Osteoporosis Canada Risk Assessment (CAROC) tool may be well calibrated to predict a category of risk for 10-year clinical fractures (low, moderate, or high risk; 1 study, n = 34,060). The evidence for most other tools was limited, or in the case of FRAX tools calibrated for countries other than Canada, very uncertain due to serious risk of bias concerns and large inconsistency in findings across studies. Postmenopausal females in a primary prevention population defined as <50% prevalence of prior fragility fracture (median 16.9%, range 0 to 48% when reported in the trials) and at risk of fragility fracture, treatment with bisphosphonates as a class (median 2 years, range 1-6 years) probably reduces the risk of clinical fragility fractures (19 RCTs, n = 22,482, ARD = 11.1 fewer in 1000, 95% CI 15.0-6.6 fewer, [number needed to treat for an additional beneficial outcome] NNT = 90), and may reduce the risk of hip fractures (14 RCTs, n = 21,038, ARD = 2.9 fewer in 1000, 95% CI 4.6-0.9 fewer, NNT = 345) and clinical vertebral fractures (11 RCTs, n = 8921, ARD = 10.0 fewer in 1000, 95% CI 14.0-3.9 fewer, NNT = 100); it may not reduce all-cause mortality. There is low certainty evidence of little-to-no reduction in hip fractures with any individual bisphosphonate, but all provided evidence of decreased risk of clinical fragility fractures (moderate certainty for alendronate [NNT=68] and zoledronic acid [NNT=50], low certainty for risedronate [NNT=128]) among postmenopausal females. Evidence for an impact on risk of clinical vertebral fractures is very uncertain for alendronate and risedronate; zoledronic acid may reduce the risk of this outcome (4 RCTs, n = 2367, ARD = 18.7 fewer in 1000, 95% CI 25.6-6.6 fewer, NNT = 54) for postmenopausal females. Denosumab probably reduces the risk of clinical fragility fractures (6 RCTs, n = 9473, ARD = 9.1 fewer in 1000, 95% CI 12.1-5.6 fewer, NNT = 110) and clinical vertebral fractures (4 RCTs, n = 8639, ARD = 16.0 fewer in 1000, 95% CI 18.6-12.1 fewer, NNT=62), but may make little-to-no difference in the risk of hip fractures among postmenopausal females. Denosumab probably makes little-to-no difference in the risk of all-cause mortality or health-related quality of life among postmenopausal females. Evidence in males is limited to two trials (1 zoledronic acid, 1 denosumab); in this population, zoledronic acid may make little-to-no difference in the risk of hip or clinical fragility fractures, and evidence for all-cause mortality is very uncertain. The evidence for treatment with denosumab in males is very uncertain for all fracture outcomes (hip, clinical fragility, clinical vertebral) and all-cause mortality. There is moderate certainty evidence that treatment causes a small number of patients to experience a non-serious adverse event, notably non-serious gastrointestinal events (e.g., abdominal pain, reflux) with alendronate (50 RCTs, n = 22,549, ARD = 16.3 more in 1000, 95% CI 2.4-31.3 more, [number needed to treat for an additional harmful outcome] NNH = 61) but not with risedronate; influenza-like symptoms with zoledronic acid (5 RCTs, n = 10,695, ARD = 142.5 more in 1000, 95% CI 105.5-188.5 more, NNH = 7); and non-serious gastrointestinal adverse events (3 RCTs, n = 8454, ARD = 64.5 more in 1000, 95% CI 26.4-13.3 more, NNH = 16), dermatologic adverse events (3 RCTs, n = 8454, ARD = 15.6 more in 1000, 95% CI 7.6-27.0 more, NNH = 64), and infections (any severity; 4 RCTs, n = 8691, ARD = 1.8 more in 1000, 95% CI 0.1-4.0 more, NNH = 556) with denosumab. For serious adverse events overall and specific to stroke and myocardial infarction, treatment with bisphosphonates probably makes little-to-no difference; evidence for other specific serious harms was less certain or not available. There was low certainty evidence for an increased risk for the rare occurrence of atypical femoral fractures (0.06 to 0.08 more in 1000) and osteonecrosis of the jaw (0.22 more in 1000) with bisphosphonates (most evidence for alendronate). The evidence for these rare outcomes and for rebound fractures with denosumab was very uncertain. Younger (lower risk) females have high willingness to be screened. A minority of postmenopausal females at increased risk for fracture may accept treatment. Further, there is large heterogeneity in the level of risk at which patients may be accepting of initiating treatment, and treatment effects appear to be overestimated.

CONCLUSION

An offer of 2-step screening with risk assessment and BMD measurement to selected postmenopausal females with low prevalence of prior fracture probably results in a small reduction in the risk of clinical fragility fracture and hip fracture compared to no screening. These findings were most applicable to the use of clinical FRAX for risk assessment and were not replicated in the offer-to-screen population where the rate of response to mailed screening questionnaires was low. Limited direct evidence on harms of screening were available; using study data to provide estimates, there may be a moderate degree of overdiagnosis of high risk for fracture to consider. The evidence for younger females and males is very limited. The benefits of screening and treatment need to be weighed against the potential for harm; patient views on the acceptability of treatment are highly variable.

SYSTEMATIC REVIEW REGISTRATION

International Prospective Register of Systematic Reviews (PROSPERO): CRD42019123767.

Adjusting conventional FRAX estimates of fracture probability according to the number of prior falls in the preceding year

A greater propensity to falling is associated with higher fracture risk. This study provides adjustments to FRAX-based fracture probabilities accounting for the number of prior falls.

INTRODUCTION

Prior falls increase subsequent fracture risk but are not currently directly included in the FRAX tool. The aim of this study was to quantify the effect of the number of prior falls on the 10-year probability of fracture determined with FRAX®.

METHODS

We studied 21,116 women and men age 40 years or older (mean age 65.7 ± 10.1 years) with fracture probability assessment (FRAX®), self-reported falls for the previous year, and subsequent fracture outcomes in a registry-based cohort. The risks of death, hip fracture, and non-hip major osteoporotic fracture (MOF-NH) were determined by Cox proportional hazards regression for fall number category versus the whole population (i.e., an average number of falls). Ten-year probabilities of hip fracture and major osteoporotic fracture (MOF) were determined according to the number of falls from the hazards of death and fracture incorporated into the FRAX model for the UK. The probability ratios (number of falls vs. average number of falls) provided adjustments to conventional FRAX estimates of fracture probability according to the number of falls.

RESULTS

Compared with the average number of falls, the hazard ratios for hip fracture, MOF-NH and death were lower than unity in the absence of a fall history. Hazard ratios increased progressively with an increasing number of reported falls. The probability ratio rose progressively as the number of reported falls increased. Probability ratios decreased with age, an effect that was more marked the greater the number of prior falls.

CONCLUSION

The probability ratios provide adjustments to conventional FRAX estimates of fracture probability according to the number of prior falls.

Should vertebral fracture assessment be performed in Fracture Liaison Service patients with non-vertebral fracture?

Prior non-vertebral fractures, except of the ankle, are associated with increased likelihood of vertebral fracture. As knowledge of vertebral fracture presence may alter care, vertebral fracture assessment (VFA) is indicated in patients with prior fracture.

INTRODUCTION

Vertebral fractures are often unappreciated. It was recently advocated that all Fracture Liaison Service (FLS) patients have densitometric VFA performed. We evaluated the likelihood of vertebral fracture identification with VFA in patients with prior fracture using the Manitoba Bone Density database. METHODS : VFA was performed in patients with T-scores below - 1.5 and age 70 + (or younger with height loss or glucocorticoid use) obtaining bone densitometry in Manitoba from 2010 to 2018. Those with prior clinical vertebral fracture, pathologic fracture, or uninterpretable VFA were excluded. Vertebral fractures were identified using the modified ABQ method. Health records were assessed for non-vertebral fracture (excluding head, neck, hand, foot) diagnosis codes unassociated with trauma prior to DXA. Multivariable odds ratios (ORs) for vertebral fracture were estimated without and with adjustment for age, sex, body mass index, ethnicity, area of residence, income level, comorbidity score, diabetes mellitus, falls in the last year, glucocorticoid use, and lowest BMD T-score.

RESULTS

The study cohort consisted of 12,756 patients (94.4% women) with mean (SD) age 75.9 (6.8) years. Vertebral fractures were identified in 1925 (15.1%) overall. Vertebral fractures were significantly more likely (descending order) in those with prior pelvis, hip, humerus, other sites, and forearm, but not ankle fracture. There was modest attenuation with covariate adjustment but statistical significance was maintained.

CONCLUSIONS

Prior hip, humerus, pelvis, forearm, and other fractures are associated with an increased likelihood of previously undiagnosed vertebral fracture, information useful for risk stratification and monitoring. These data support recommending VFA in FLS patients who are age 70 + with low BMD.

Menopausal hormone therapy reduces the risk of fracture regardless of falls risk or baseline FRAX probability-results from the Women's Health Initiative hormone therapy trials

In a combined analysis of 25,389 postmenopausal women aged 50-79 years, enrolled in the two Women's Health Initiative hormone therapy trials, menopausal hormone therapy vs. placebo reduced the risk of fracture regardless of baseline FRAX fracture probability and falls history.

INTRODUCTION

The aim of this study was to determine if the anti-fracture efficacy of menopausal hormone therapy (MHT) differed by baseline falls history or fracture risk probability as estimated by FRAX, in a combined analysis of the two Women's Health Initiative (WHI) hormone therapy trials.

METHODS

A total of 25,389 postmenopausal women aged 50-79 years were randomized to receive MHT (n = 12,739) or matching placebo (n = 12,650). At baseline, questionnaires were used to collect information on falls history, within the last 12 months, and clinical risk factors. FRAX 10-year probability of major osteoporotic fracture (MOF) was calculated without BMD. Incident clinical fractures were verified using medical records. An extension of Poisson regression was used to investigate the relationship between treatment and fractures in (1) the whole cohort; (2) those with prior falls; and (3) those without prior falls. The effect of baseline FRAX probability on efficacy was investigated in the whole cohort.

RESULTS

Over 4.3 ± 2.1 years (mean ± SD), MHT (vs. placebo) significantly reduced the risk of any clinical fracture (hazard ratio [HR] 0.72 [95% CI, 0.65-0.78]), MOF (HR 0.60 [95% CI, 0.53-0.69]), and hip fracture (0.66 [95% CI, 0.45-0.96]). Treatment was effective in reducing the risk of any clinical fracture, MOF, and hip fracture in women regardless of baseline FRAX MOF probability, with no evidence of an interaction between MHT and FRAX (p > 0.30). Similarly, there was no interaction (p > 0.30) between MHT and prior falls.

CONCLUSION

In the combined WHI trials, compared to placebo, MHT reduces fracture risk regardless of FRAX probability and falls history in postmenopausal women.

Update of the fracture risk prediction tool FRAX: a systematic review of potential cohorts and analysis plan

We describe the collection of cohorts together with the analysis plan for an update of the fracture risk prediction tool FRAX with respect to current and novel risk factors. The resource comprises 2,138,428 participants with a follow-up of approximately 20 million person-years and 116,117 documented incident major osteoporotic fractures.

INTRODUCTION

The availability of the fracture risk assessment tool FRAX® has substantially enhanced the targeting of treatment to those at high risk of fracture with FRAX now incorporated into more than 100 clinical osteoporosis guidelines worldwide. The aim of this study is to determine whether the current algorithms can be further optimised with respect to current and novel risk factors.

METHODS

A computerised literature search was performed in PubMed from inception until May 17, 2019, to identify eligible cohorts for updating the FRAX coefficients. Additionally, we searched the abstracts of conference proceedings of the American Society for Bone and Mineral Research, European Calcified Tissue Society and World Congress of Osteoporosis. Prospective cohort studies with data on baseline clinical risk factors and incident fractures were eligible.

RESULTS

Of the 836 records retrieved, 53 were selected for full-text assessment after screening on title and abstract. Twelve cohorts were deemed eligible and of these, 4 novel cohorts were identified. These cohorts, together with 60 previously identified cohorts, will provide the resource for constructing an updated version of FRAX comprising 2,138,428 participants with a follow-up of approximately 20 million person-years and 116,117 documented incident major osteoporotic fractures. For each known and candidate risk factor, multivariate hazard functions for hip fracture, major osteoporotic fracture and death will be tested using extended Poisson regression. Sex- and/or ethnicity-specific differences in the weights of the risk factors will be investigated. After meta-analyses of the cohort-specific beta coefficients for each risk factor, models comprising 10-year probability of hip and major osteoporotic fracture, with or without femoral neck bone mineral density, will be computed.

CONCLUSIONS

These assembled cohorts and described models will provide the framework for an updated FRAX tool enabling enhanced assessment of fracture risk (PROSPERO (CRD42021227266)).

Association between incident falls and subsequent fractures in patients attending the fracture liaison service after an index fracture: a 3-year prospective observational cohort study

OBJECTIVES

To evaluate the risk of subsequent fractures in patients who attended the Fracture Liaison Service (FLS), with and without incident falls after the index fracture.

DESIGN

A 3-year prospective observational cohort study.

SETTING

An outpatient FLS in the Netherlands.

PARTICIPANTS

Patients aged 50+ years with a recent clinical fracture.

OUTCOME MEASURES

Incident falls and subsequent fractures.

RESULTS

The study included 488 patients (71.9% women, mean age: 64.6±8.6 years). During the 3-year follow-up, 959 falls had been ascertained in 296 patients (60.7%) (ie, fallers), and 60 subsequent fractures were ascertained in 53 patients (10.9%). Of the fractures, 47 (78.3%) were fall related, of which 25 (53.2%) were sustained at the first fall incident at a median of 34 weeks. An incident fall was associated with an approximately 9-fold (HR: 8.6, 95% CI 3.1 to 23.8) increase in the risk of subsequent fractures.

CONCLUSION

These data suggest that subsequent fractures among patients on treatment prescribed in an FLS setting are common, and that an incident fall is a strong predictor of subsequent fracture risk. Immediate attention for fall risk could be beneficial in an FLS model of care.

TRIAL REGISTRATION NUMBER

NL45707.072.13.

Is it time to consider population screening for fracture risk in postmenopausal women? A position paper from the International Osteoporosis Foundation Epidemiology/Quality of Life Working Group

The IOF Epidemiology and Quality of Life Working Group has reviewed the potential role of population screening for high hip fracture risk against well-established criteria. The report concludes that such an approach should strongly be considered in many health care systems to reduce the burden of hip fractures.

INTRODUCTION

The burden of long-term osteoporosis management falls on primary care in most healthcare systems. However, a wide and stable treatment gap exists in many such settings; most of which appears to be secondary to a lack of awareness of fracture risk. Screening is a public health measure for the purpose of identifying individuals who are likely to benefit from further investigations and/or treatment to reduce the risk of a disease or its complications. The purpose of this report was to review the evidence for a potential screening programme to identify postmenopausal women at increased risk of hip fracture.

METHODS

The approach took well-established criteria for the development of a screening program, adapted by the UK National Screening Committee, and sought the opinion of 20 members of the International Osteoporosis Foundation's Working Group on Epidemiology and Quality of Life as to whether each criterion was met (yes, partial or no). For each criterion, the evidence base was then reviewed and summarized.

RESULTS AND CONCLUSION

The report concludes that evidence supports the proposal that screening for high fracture risk in primary care should strongly be considered for incorporation into many health care systems to reduce the burden of fractures, particularly hip fractures. The key remaining hurdles to overcome are engagement with primary care healthcare professionals, and the implementation of systems that facilitate and maintain the screening program.

The Effect of Fracture Recency on Observed 10-Year Fracture Probability: A Registry-Based Cohort Study

FRAX estimates 10-year fracture major osteoporotic fracture (MOF) and hip fracture probability from multiple risk factors. FRAX does not consider prior fracture site or time since fracture. Fracture risk is greater in the initial 2-year post-fracture period (imminent risk), implying that FRAX may underestimate risk in this setting. We used the population-based Manitoba Bone Mineral Density (BMD) Program registry to examine the effect of fracture recency and site on incident fracture risk predictions using FRAX. We identified women aged 40 years or older with baseline BMD and FRAX scores. Observed fracture outcomes to 10 years were compared with predicted 10-year fracture probability stratified by prior fracture status: none, recent (<2 years [median 0.3 years]), and remote (≥2 years [median 10.6 years]). For women with recent fractures, we also examined proposed multipliers to adjust FRAX for the effect of fracture recency and site. The cohort comprised 33,465 women aged 40 to 64 years (1897 recent fracture, 2120 remote fracture) and 33,806 women aged ≥65 years (2365 fracture, 4135 remote fracture). Observed fracture probability was consistent with predicted probability in most analyses. In women aged 40 to 64 years, there was a significant effect of recent vertebral and humerus fracture on MOF (observed to predicted 1.61 and 1.48, respectively), but these effects were still lower than the proposed multipliers (2.32 and 1.67, respectively). No significant effect of fracture recency was found after hip or forearm fracture in either age group. Our findings contribute to accumulating evidence of the importance of recent fracture. The effect of fracture recency was not consistent across fracture sites and with a lower magnitude than previously reported. Further quantification of effect size and specificity in additional independent cohorts is warranted to validate and refine recent-fracture multipliers in fracture risk assessment. © 2022 American Society for Bone and Mineral Research (ASBMR).

Fracture Risk Assessment: An Update

➤

Our ability to accurately identify high fracture risk in individuals has improved as the volume of clinical data has expanded and fracture risk assessment tools have been developed.

➤

Given its accessibility, affordability, and low radiation exposure, dual x-ray absorptiometry (DXA) remains the standard for osteoporosis screening and monitoring response to treatment.

➤

The trabecular bone score (TBS) is a DXA software add-on that uses lumbar spine DXA imaging to produce an output that correlates with bone microarchitecture. It has been identified as an independent fracture risk factor and may prove useful in further stratifying fracture risk among those with a bone mineral density (BMD) in the osteopenic range (-1.0 to -2.4 standard deviations), in those with low-energy fractures but normal or only mildly low BMD, or in those with conditions known to impair bone microarchitecture.

➤

Fracture risk assessment tools, including the Fracture Risk Assessment Tool (FRAX), Garvan fracture risk calculator, and QFracture, evaluate the impact of multiple clinical factors on fracture risk, even in the absence of BMD data. Each produces an absolute fracture risk output over a defined interval of time. When used appropriately, these enhance our ability to identify high-risk patients and allow us to differentiate fracture risk among patients who present with similar BMDs.

➤

For challenging clinical cases, a combined approach is likely to improve accuracy in the identification of high-risk patients who would benefit from the available osteoporosis therapies.

Osteoporosis epidemiology using international cohorts

PURPOSE OF REVIEW

The field of osteoporosis research has been active for the past 20 years and has allowed significant advancement in the management of osteoporosis. This review will give an overview of the latest data from international cohorts that relate to current and recent osteoporosis research.

RECENT FINDINGS

The clinical diagnosis of osteoporosis relies heavily on bone mineral density (BMD) measured at femoral neck or spine and although BMD has excellent predictive value for future fractures, fracture risk assessment has evolved over the years, resulting in the birth of fracture prediction tools. Fracture risk factors not currently featured in these tools are being considered for inclusion, including imminent risk fracture following a sentinel fracture, number of falls, and previous vertebral fractures. Data from groups with comorbidities such as chronic obstructive pulmonary disease are helping us understand how to best manage patients with multiple comorbidities. Finally, the prevalence of vertebral fracture in the older general population and other selected populations has been explored, alongside the global burden of osteoporosis and its consequences.

SUMMARY

Our understanding of osteoporosis continues to expand, but knowledge gaps remain.

Approaches to Fracture Risk Assessment and Prevention

PURPOSE OF REVIEW

To critically assess recent evidence concerning osteoporosis fracture risk.

RECENT FINDINGS

Robust instruments exist for predicting factures incorporating well-documented risk factors especially prior fracture whose magnitude varies with site, occurrence time, and age. Stratifying time-since-prior fracture has resulted in the concept of imminent fracture risk and increased focus on secondary fracture prevention. Secondary fracture prevention recommendations include fracture liaison service, pharmacologic and non-pharmacologic multidisciplinary intervention, and communicating that fractures in older adults are the predictable consequence of underlying osteoporosis rather than unfortunate accidents. Quality improvement in osteoporosis care includes diagnosing osteoporosis on the basis of clinical fractures rather than exclusively relying on bone density testing; applying diagnostic rather than screening approaches to patients with prior fractures; regularly updating fall and fracture histories; performing a physical exam focused on spinal curvature, posture, and musculoskeletal function; reviewing images to identify prevalent fractures that may have been missed; and general use of fracture risk algorithms at all stages of osteoporosis management. Communicating effectively with patients about osteoporosis and fractures, their consequences, and pharmacological and non-pharmacological management is the cornerstone of high-value care.

Fracture prediction from FRAX for Canadian ethnic groups: a registry-based cohort study

We identified large between-ethnicity calibration differences in the Canadian FRAX® tool which substantially overestimated the major osteoporotic fracture (MOF) risk in Asian women and Black women, and overestimated hip fracture risk in Asian women.

PURPOSE

FRAX® is calibrated using population-specific fracture and mortality data. The need for FRAX to accommodate ethnic diversity within a country is uncertain. We addressed this question using the population-based Manitoba Bone Mineral Density (BMD) Program registry and self-reported ethnicity.

METHODS

The study population was women aged 40 years or older with baseline FRAX assessments (Canadian and other ethnic calculators), fracture outcomes, and self-reported ethnicity (White N = 68,907 [referent], Asian N = 1910, Black N = 356). Adjusted hazard ratios (HR) with 95% confidence intervals (CI) for time to MOF and hip fracture were estimated. We examined candidate variables from DXA that might contribute to ethnic differences including skeletal size, hip axis length (HAL), trabecular bone score (TBS), and estimated body composition.

RESULTS

Adjusted for baseline risk using the Canadian FRAX tool with BMD, Asian women compared with White women were at much lower risk for MOF (HR 0.46, 95% CI 0.35-0.59) and hip fracture (0.16, 95% CI 0.08-0.34). Black women were also at lower MOF risk (HR 0.58, 95% CI 0.32-1.00); there were no hip fractures. The US ethnic-specific FRAX calculators accounted for most of the between-ethnicity differences in MOF risk (86% for Asian, 92% for Black) but only partially accounted for lower hip fracture risk in Asian women (40%). The candidate variables explained only a minority of the effect of ethnicity. Gradient of risk in analyses was similar (p-interactions ethnicity*FRAX non-significant).

CONCLUSIONS

We identified significant ethnic differences in performance of the Canadian FRAX tool with fracture probability overestimated among Asian and Black women. The US ethnic calculators helped to address this discrepancy for MOF risk assessment, but not for hip fracture risk among Asian women.

Cost-effectiveness of Screening for Osteoporosis in Older Men With a History of Falls

Importance

Falls and osteoporosis share the potential clinical end point of fractures among older patients. To date, few fall prevention guidelines incorporate screening for osteoporosis to reduce fall-related fractures.

Objective

To assess the cost-effectiveness of screening for osteoporosis using dual-energy x-ray absorptiometry (DXA) followed by osteoporosis treatment in older men with a history of falls.

Design, Setting, and Participants

In this economic evaluation, a Markov model was developed to simulate the incidence of major osteoporotic fractures in a hypothetical cohort of community-dwelling men aged 65 years who had fallen at least once in the past year. Data sources included literature published from January 1, 1946, to July 31, 2020. The model adopted a societal perspective, a lifetime horizon, a 1-year cycle length, and a discount rate of 3% per year for both health benefits and costs. The analysis was designed and conducted from October 1, 2019, to September 30, 2020.

Interventions

Screening with DXA followed by treatment for men diagnosed with osteoporosis compared with usual care.

Main Outcomes and Measures

Incremental cost-effectiveness ratio (ICER), measured by cost per quality-adjusted life-year (QALY) gained.

Results

Among the hypothetical cohort of men aged 65 years, the screening strategy had an ICER of $33 169/QALY gained and was preferred over usual care at the willingness-to-pay threshold of $100 000/QALY gained. The number needed to screen to prevent 1 hip fracture was 1876; to prevent 1 major osteoporotic fracture, 746. The screening strategy would become more effective and less costly than usual care for men 77 years and older. The ICER for the screening strategy did not substantially change across a wide range of assumptions tested in all other deterministic sensitivity analyses. At a willingness-to-pay threshold of $50 000/QALY gained, screening was cost-effective in 56.0% of simulations; at $100 000/QALY gained, 90.8% of simulations; and at $200 000/QALY gained, 99.6% of simulations.

Conclusions and Relevance

These findings suggest that for older men who have fallen at least once in the past year, screening with DXA followed by treatment for those diagnosed with osteoporosis is a cost-effective use of resources. Fall history could be a useful cue to trigger assessment for osteoporosis in men.

Differences in fracture prevalence and in bone mineral density between Chinese and White Canadians: the Canadian Multicentre Osteoporosis Study (CaMos)

Fracture determinants differ between Canadians of Chinese and White descent, the former constituting the second largest visible minority group in Canada. The results of this study support the importance of characterizing bone health predictors in Canadians of different ethnicity to improve population-specific fracture prevention and treatment strategies.

PURPOSE

We aimed to compare clinical risk factors, bone mineral density, prevalence of osteoporosis, and fractures between Chinese and White Canadians to identify ethnicity-specific risks.

METHODS

We studied 236 Chinese and 8945 White Canadians aged 25+ years from the Canadian Multicentre Osteoporosis Study (CaMos). The prevalence of osteoporosis using ethnicity-specific peak bone mass (PBM), and of prior and incident low trauma fractures were assessed and compared between groups. Linear regressions, adjusting for age and anthropometric measures, were used to examine the association between baseline and 5-year changes in BMD and ethnicity.

RESULTS

Chinese participants had shorter stature, lower BMI, and lower rate of falls than White participants. Adjusted models showed no significant differences in baseline BMD between ethnic groups except in younger men where total hip BMD was 0.059 g/cm² (0.009; 0.108) lower in Chinese. Adjusted 5-year BMD change at lumbar spine was higher in older Chinese women and men compared with Whites. When using Chinese-specific PBM, the prevalence of osteoporosis in Chinese women was 2-fold lower than when using that of White women The prevalence of fractures was higher in White women compared with Chinese with differences up to 14.5% (95% CI 9.2; 19.7) and 10.5% (95% CI 4.5-16.4) in older White men. Incident fractures were rare in young Chinese compared with White participants and not different in the older groups.

CONCLUSION

Our results support the importance of characterizing bone strength predictors in Chinese Canadians and the development of ethnicity-specific fracture prediction and prevention strategies.

New Developments in Fracture Risk Assessment for Current Osteoporosis Reports

PURPOSE OF REVIEW

Identifying individuals at high fracture risk can be used to target those likely to derive the greatest benefit from treatment. This narrative review examines recent developments in using specific risk factors used to assess fracture risk, with a focus on publications in the last 3 years.

RECENT FINDINGS

There is expanding evidence for the recognition of individual clinical risk factors and clinical use of composite scores in the general population. Unfortunately, enthusiasm is dampened by three pragmatic randomized trials that raise questions about the effectiveness of widespread population screening using clinical fracture prediction tools given suboptimal participation and adherence. There have been refinements in risk assessment in special populations: men, patients with diabetes, and secondary causes of osteoporosis. New evidence supports the value of vertebral fracture assessment (VFA), high resolution peripheral quantitative CT (HR-pQCT), opportunistic screening using CT, skeletal strength assessment with finite element analysis (FEA), and trabecular bone score (TBS). The last 3 years have seen important developments in the area of fracture risk assessment, both in the research setting and translation to clinical practice. The next challenge will be incorporating these advances into routine work flows that can improve the identification of high risk individuals at the population level and meaningfully impact the ongoing crisis in osteoporosis management.

A decade of FRAX: how has it changed the management of osteoporosis?

The fracture risk assessment tool, FRAX^®, was released in 2008 and provides country-specific algorithms for estimating individualized 10-year probability of hip and major osteoporotic fracture (hip, clinical spine, distal forearm, and proximal humerus). Since its release, 71 models have been made available for 66 countries covering more than 80% of the world population. The website receives approximately 3 million visits annually. Following independent validation, FRAX has been incorporated into more than 80 guidelines worldwide. The application of FRAX in assessment guidelines has been heterogeneous with the adoption of several different approaches in setting intervention thresholds. Whereas most guidelines adopt a case-finding strategy, the case for FRAX-based community screening in the elderly is increasing. The relationship between FRAX and efficacy of intervention has been explored and is expected to influence treatment guidelines in the future.

Comparison of treatment strategies and thresholds for optimizing fracture prevention in Canada: a simulation analysis

This comparison of osteoporosis treatment strategies and intervention thresholds highlights tradeoffs in terms of number of individuals qualifying for treatment and estimated fractures prevented.

PURPOSE

The current analysis was performed to inform the following key question as part of the Osteoporosis Canada's Osteoporosis Guidelines Update: "What is the best strategy to identify those at high fracture risk for pharmacotherapy in order to prevent the most fractures, considering both population and patient perspectives?"

METHODS

The study population consisted of 66,878 women age 50 years and older (mean age 66.0 ± 9.7 years) with documented fracture probability assessment (FRAX) and fracture outcomes. Fractures over the next 5 years were identified through linked administrative healthcare data. We estimated the fraction of the population that would warrant treatment and the number of fractures avoided per 1000 person-years according to multiple strategies and thresholds. Strategies were then rank ordered using 19 metrics.

RESULTS

During mean 4.4 years, 863 (3.5%) sustained one or more major osteoporotic fractures (MOF), 212 (0.8%) sustained a hip fracture, and 1210 (4.9%) sustained any incident fracture. For woman age 50-64 years, the highest ranked strategy was treatment based upon total hip T score ≤ -2.5, but several other strategies fell within 0.5 overall ranking. For women age 65 years and older, MOF > 20% was the highest ranked strategy with no closely ranked strategies. Pooling both age subgroups gave MOF > 20% as the highest ranked strategy, with several other strategies within 0.5 overall ranking.

CONCLUSIONS

Choice of treatment strategy and threshold for osteoporosis management strongly influences the number of individuals for whom pharmacologic treatment would be recommended and on estimated fracture rates in the population. This evidence-based approach to comparing these strategies will help to inform guidelines development in Canada and may be on interest elsewhere.