Fracture risk prediction using BMD and clinical risk factors in early postmenopausal women: Sensitivity of the WHO FRAX tool

The aim of this prospective study was (1) to identify significant and independent clinical risk factors (CRFs) for major osteoporotic (OP) fracture among peri‐ and early postmenopausal women, (2) to assess, in this population, the discriminatory capacity of FRAX and bone mineral density (BMD) for the identification of women at high risk of fracture, and (3) to assess whether adding risk factors to either FRAX or BMD would improve discriminatory capacity. The study population included 2651 peri‐ and early postmenopausal women [mean age (± SD): 54 ± 4 years] with a mean follow‐up period of 13.4 years (±1.4 years). At baseline, a large set of CRFs was recorded, and vertebral BMD was measured (Lunar, DPX) in all women. Femoral neck BMD also was measured in 1399 women in addition to spine BMD. Women with current or past OP treatment for more than 3 months at baseline (n = 454) were excluded from the analyses. Over the follow‐up period, 415 women sustained a first low‐energy fracture, including 145 major OP fractures (108 wrist, 44 spine, 20 proximal humerus, and 13 hip). In Cox multivariate regression models, only 3 CRFs were significant predictors of a major OP fracture independent of BMD and age: a personal history of fracture, three or more pregnancies, and current postmenopausal hormone therapy. In the subsample of women who had a hip BMD measurement and who were not receiving OP therapy (including hormone‐replacement therapy) at baseline, mean FRAX value was 3.8% (±2.4%). The overall discriminative value for fracture, as measured by the area under the Receiver Operating Characteristic (ROC) curve (AUC), was equal to 0.63 [95% confidence interval (CI) 0.56–0.69] and 0.66 (95% CI 0.60–0.73), respectively, for FRAX and hip BMD. Sensitivity of both tools was low (ie, around 50% for 30% of the women classified as the highest risk). Adding parity to the predictive model including FRAX or using a simple risk score based on the best predictive model in our population did not significantly improve the discriminatory capacity over BMD alone. Only a limited number of clinical risk factors were found associated with the risk of major OP fracture in peri‐ and early postmenopausal women. In this population, the FRAX tool, like other risk scores combining CRFs to either BMD or FRAX, had a poor sensitivity for fracture prediction and did not significantly improve the discriminatory value of hip BMD alone. © 2010 American Society for Bone and Mineral Research     

Selection of Women Aged 50–64 Yr for Bone Density Measurement

The fracture risk assessment tool from the World Health Organization (FRAX^®) estimates 10-yr major osteoporotic and hip fracture probabilities from multiple clinical risk factors and optionally femoral neck bone mineral density (BMD). FRAX without BMD has been proposed as a method to select postmenopausal women younger than 65 yr for BMD measurement, but the efficiency of this strategy and its concordance with National Osteoporosis Foundation (NOF) treatment guidelines is unknown. The osteoporosis self-assessment test (OST) is another simple screening tool based on age and weight alone. A historical cohort of 18,315 women aged 50–64 yr, drawn from the Manitoba Bone Density Program database, which contains clinical BMD results for the Province of Manitoba, Canada, was used to determine the performance of these screening tools in selecting postmenopausal women younger than 65 yr for BMD testing. FRAX was closely aligned with indicators of high fracture risk (area under the receiver operating characteristic curve [AUROC]: 0.89), whereas OST was better for detecting women with osteoporotic BMD (AUROC: 0.72). The combination of major fracture probability 10% or higher from FRAX without BMD or OST less than 1 identified 42% of women for BMD testing, capturing 72% of women meeting any NOF treatment criteria (90% of women with NOF criteria for high risk from FRAX or prior fracture). The negative predictive value to exclude qualification for treatment under the NOF criteria was 90%. These data may help to inform an evidence-based approach for targeting BMD testing in postmenopausal women younger than 65 yr under the NOF treatment guidelines.     

Predictive value of FRAX for fracture in obese older women

Recent studies indicate that obesity is not protective against fracture in postmenopausal women and increases the risk of fracture at some sites. Risk factors for fracture in obese women may differ from those in the nonobese. We aimed to compare the ability of FRAX with and without bone mineral density (BMD) to predict fractures in obese and nonobese older postmenopausal women who were participants in the Study of Osteoporotic Fractures. Data for FRAX clinical risk factors and femoral neck BMD were available in 6049 women, of whom 18.5% were obese. Hip fractures, major osteoporotic fractures, and any clinical fractures were ascertained during a mean follow‐up period of 9.03 years. Receiving operator curve (ROC) analysis, model calibration, and decision curve analysis were used to compare fracture prediction in obese and nonobese women. ROC analysis revealed no significant differences between obese and nonobese women in fracture prediction by FRAX, with or without BMD. Predicted hip fracture risk was lower than observed risk in both groups of women, particularly when FRAX + BMD was used, but there was good calibration for FRAX + BMD in prediction of major osteoporotic fracture in both groups. Decision curve analysis demonstrated that both FRAX models were useful for hip fracture prediction in obese and nonobese women for threshold 10‐year fracture probabilities in the range of 4% to 10%, although in obese women FRAX + BMD was superior to FRAX alone. For major osteoporotic fracture, both FRAX models were useful in both groups of women for threshold probabilities in the range of 10% to 30%. For all clinical fractures, the FRAX models were not useful at threshold probabilities below 30%. We conclude that FRAX is of value in predicting hip and major osteoporotic fractures in obese postmenopausal women, particularly when used with BMD. © 2013 American Society for Bone and Mineral Research     

Case finding for the management of osteoporosis with FRAX<Superscript>®</Superscript>—assessment and intervention thresholds for the UK

Assessment and intervention thresholds are developed and proposed in men aged over 50 years and postmenopausal women for the UK based on fracture probability from the WHO fracture risk assessment tool (FRAX((R))). INTRODUCTION: The FRAX((R)) tool has recently become available to compute the 10-year probability of fractures in men and women from clinical risk factors (CRFs) with or without the measurement of femoral neck bone mineral density (BMD). The aim of this study was to develop a case-finding strategy for men and women from the UK at high risk of osteoporotic fracture by delineating the fracture probabilities at which BMD testing or intervention should be recommended. METHODS: Fracture probabilities were computed using the FRAX((R)) tool calibrated to the epidemiology of fracture and death in the UK. The relationship between cost effectiveness and fracture probability used the source data from a prior publication that examined the cost effectiveness of generic alendronate in the UK. An intervention threshold was set by age in men and women, based on the fracture probability equivalent to that of women with a history of a prior osteoporosis related fracture. In addition, assessment thresholds for the use of BMD testing were explored. Assessment thresholds for the measurement of BMD followed current practice guidelines where individuals were considered to be eligible for assessment in the presence of one or more CRF. An upper assessment threshold (i.e. a fracture probability above which patients could be treated without recourse to BMD) was based on optimisation of the positive predictive value of the assessment tool. The consequences of assessment and intervention thresholds on the requirement for BMD test and interventions were assessed using the distribution of clinical risk factors and femoral neck BMD for women in the source cohorts used for the development of the FRAX((R)) models RESULTS: Treatment was cost effective at all ages when the 10-year probability of a major fracture exceeded 7%. The intervention threshold at the age of 50 years corresponded to a 10-year probability of a major osteoporotic fracture of 7.5%. This rose progressively with age to 30% at the age of 80 years, so that intervention was cost effective at all ages. Assessment thresholds for testing with BMD (6-9% at the age of 50 years) also rose with age (18-36% at the age of 80 years). The use of these thresholds in a case-finding strategy would identify 6-20% of women as eligible for BMD testing and 23-46% as eligible for treatment, depending on age. The same threshold can be used in men. CONCLUSION: The study provides a method of developing management algorithms for osteoporosis from the estimation of fracture probabilities, rather than those based on BMD alone or BMD with single or multiple CRFs.     

The clinical utility of FRAX to discriminate fracture status in men and women with chronic kidney disease

Summary

We assessed the ability of the World Health Organization’s fracture risk assessment tool (FRAX), bone mineral density (BMD), and age to discriminate fracture status in adults with pre-dialysis chronic kidney disease (CKD). In adults with CKD, FRAX was able to discriminate fracture status but performed no better than BMD alone.

Introduction

Patients with CKD are at increased risk for fracture but the best method to assess fracture risk is not known.

Methods

We assessed the ability of the World Health Organization’s FRAX, compared with BMD at the femoral neck (FN), and age to discriminate fracture status (prevalent clinical nonspine and/or morphometric vertebral) in men and women, 18 years and older with pre-dialysis CKD. Results are presented as area under receiver operator characteristic curves (AUC) with 95 % confidence intervals (CI).

Results

We enrolled 353 subjects; mean age was 65?±?14 years; weight was 79?±?18 kg, and estimated glomerular filtration rate was 28 ml/min/1.73 m². About one third of the subjects had a prevalent clinical nonspine and/or morphometric vertebral fracture. FRAX was able to discriminate among those with prevalent clinical nonspine fractures (AUC, 0.72; 95 % CI, 0.65–0.78), morphometric vertebral fractures (AUC, 0.66; 95 % CI, 0.59–0.73), and any fracture (AUC, 0.71; 95 % CI, 0.65–0.77). The discriminative ability of BMD at the FN alone was similar to FRAX for morphometric vertebral and any fractures; FRAX performed better than BMD for prevalent clinical nonspine fractures (AUC for BMD alone, 0.66; 95 % CI, 0.60–0.73). Compared to FRAX, the AUC for age alone was lower for all fracture types.

Conclusions

Among men and women with CKD, FRAX is able to discriminate fracture status but performs no better than BMD alone.     

Evaluation of the FRAX and Garvan fracture risk calculators in older women

Fracture risk calculators estimate the absolute risk of osteoporotic fractures. We investigated the performance of the FRAX and Garvan Institute fracture risk calculators in healthy, older, New Zealand, postmenopausal women with normal bone mineral density (BMD) for their age. Fractures were ascertained in women initially enrolled in a 5‐year trial of calcium supplements and followed on average for 8.8 years. Baseline data (1422 women, mean age 74 years, mean femoral neck BMD T‐score –1.3) were used to estimate fracture risk during follow‐up using the FRAX and Garvan calculators. The FRAX–New Zealand tool was used both with and without baseline BMD. The discrimination of the calculators was assessed using the area under the curve (AUC) of receiver operating characteristic curves. The calibration was assessed by comparing estimated risk of fracture with fracture incidence across a range of estimated fracture risks and clinical factors. For each fracture subtype, the calculators had comparable moderate predictive discriminative ability (AUC range: hip fracture 0.67–0.70; osteoporotic fracture 0.62–0.64; any fracture 0.60–0.63) that was similar to that of models using only age and BMD. The Garvan calculator was well calibrated for osteoporotic fractures but overestimated hip fractures. FRAX with BMD underestimated osteoporotic and hip fractures. FRAX without BMD underestimated osteoporotic and overestimated hip fractures. In summary, none of the calculators provided better discrimination than models based on age and BMD, and their discriminative ability was only moderate, which may limit their clinical utility. The calibration varied, suggesting that the calculators should be validated in local cohorts before clinical use. © 2011 American Society for Bone and Mineral Research.     

Fracture prediction and calibration of a Canadian FRAX? tool: a population-based report from CaMos

Summary

A new Canadian WHO fracture risk assessment (FRAX?) tool to predict 10-year fracture probability was compared with observed 10-year fracture outcomes in a large Canadian population-based study (CaMos). The Canadian FRAX tool showed good calibration and discrimination for both hip and major osteoporotic fractures.

Introduction

The purpose of this study was to validate a new Canadian WHO fracture risk assessment (FRAX?) tool in a prospective, population-based cohort, the Canadian Multicentre Osteoporosis Study (CaMos).

Methods

A FRAX tool calibrated to the Canadian population was developed by the WHO Collaborating Centre for Metabolic Bone Diseases using national hip fracture and mortality data. Ten-year FRAX probabilities with and without bone mineral density (BMD) were derived for CaMos women (N?=?4,778) and men (N?=?1,919) and compared with observed fracture outcomes to 10?years (Kaplan?CMeier method). Cox proportional hazard models were used to investigate the contribution of individual FRAX variables.

Results

Mean overall 10-year FRAX probability with BMD for major osteoporotic fractures was not significantly different from the observed value in men [predicted 5.4% vs. observed 6.4% (95%CI 5.2?C7.5%)] and only slightly lower in women [predicted 10.8% vs. observed 12.0% (95%CI 11.0?C12.9%)]. FRAX was well calibrated for hip fracture assessment in women [predicted 2.7% vs. observed 2.7% (95%CI 2.2?C3.2%)] but underestimated risk in men [predicted 1.3% vs. observed 2.4% (95%CI 1.7?C3.1%)]. FRAX with BMD showed better fracture discrimination than FRAX without BMD or BMD alone. Age, body mass index, prior fragility fracture and femoral neck BMD were significant independent predictors of major osteoporotic fractures; sex, age, prior fragility fracture and femoral neck BMD were significant independent predictors of hip fractures.

Conclusion

The Canadian FRAX tool provides predictions consistent with observed fracture rates in Canadian women and men, thereby providing a valuable tool for Canadian clinicians assessing patients at risk of fracture.     

Spine-Hip T-Score Difference Predicts Major Osteoporotic Fracture Risk Independent of FRAX: A Population-Based Report From CAMOS

The WHO fracture risk assessment tool (FRAX^®) estimates an individual’s 10-yr major osteoporotic and hip fracture probabilities. When bone mineral density (BMD) is included in the FRAX calculation, only the femoral neck measurement can be used. Recently, a procedure was reported for adjusting major osteoporotic fracture probability from FRAX with femoral neck BMD based on the difference (offset) between the lumbar spine and the femoral neck T-score values. The objective of the current analysis was to independently evaluate this algorithm in a population-based cohort of 4575 women and 1813 men aged 50 yr and older from the Canadian Multicentre Osteoporosis Study. For women and men combined, there was a 15% (95% confidence interval 7–24%) increase in major osteoporotic fracture risk for each offset T-score after adjusting for FRAX probability calculated with femoral neck BMD. The effect was stronger in women than men, but a significant sex interaction was not detected. Among the full cohort, 5.5% had their risk category reclassified after using the offset adjustment. Sex- and age-dependent offsets (equivalent to an offset based on Z-scores) showed improved risk classification among individuals designated to be at moderate risk with the conventional FRAX probability measurement. In summary, the T-score difference between the lumbar spine and femoral neck is an independent risk factor for major osteoporotic fractures that is independent of the FRAX probability calculated with femoral neck BMD.     

Construction of a FRAX? model for the assessment of fracture probability in Canada and implications for treatment

Summary

We describe the creation of a FRAX? model for the assessment of fracture probability in Canadian men and women, calibrated from national hip fracture and mortality data. This FRAX tool was used to examine possible thresholds for therapeutic intervention in Canada in two large complementary cohorts of women and men.

Objective

To evaluate a Canadian World Health Organization (WHO) fracture risk assessment (FRAX?) tool for computing 10-year probabilities of osteoporotic fracture.

Methods

Fracture probabilities were computed from national hip fracture data (2005) and death hazards (2004) for Canada. Probabilities took account of age, sex, clinical risk factors (CRFs), and femoral neck bone mineral density (BMD). Treatment implications were studied in two large cohorts of individuals age 50?years and older: the population-based Canadian Multicentre Osteoporosis Study (4,778 women and 1,919 men) and the clinically referred Manitoba BMD Cohort (36,730 women and 2,873 men).

Results

Fracture probabilities increased with age, decreasing femoral neck T-score, and number of CRFs. Among women, 10.1?C11.3% would be designated high risk based upon 10-year major osteoporotic fracture probability exceeding 20%. A much larger proportion would be designated high risk based upon 10-year hip fracture probability exceeding 3% (25.7?C28.0%) or osteoporotic BMD (27.1?C30.9%), and relatively few from prior hip or clinical spine fracture (1.6?C4.2%). One or more criteria for intervention were met by 29.2?C34.0% of women excluding hip fracture probability (35.3?C41.0% including hip fracture probability). Lower intervention rates were seen among CaMos (Canadian Multicentre Osteoporosis Study) men (6.8?C12.9%), but in clinically referred men from the Manitoba BMD Cohort, one or more criteria for high risk were seen for 26.4% excluding hip fracture probability (42.4% including hip fracture probability).

Conclusions

The FRAX tool can be used to identify intervention thresholds in Canada. The FRAX model supports a shift from a dual X-ray absorptiometry (DXA)-based intervention strategy, towards a strategy based on fracture probability for a major osteoporotic fracture.     

The Effect of Abaloparatide‐SC on Fracture Risk Is Independent of Baseline FRAX Fracture Probability: A Post Hoc Analysis of the ACTIVE Study

Daily subcutaneous (SC) injections of the investigational drug abaloparatide‐SC (80 mcg) for 18 months significantly decrease the risk of vertebral and nonvertebral fracture compared with placebo in postmenopausal women. We examined the efficacy of abaloparatide‐SC as a function of baseline fracture risk, assessed using the FRAX tool. Baseline clinical risk factors (age, body mass index [BMI], prior fracture, glucocorticoid use, rheumatoid arthritis, and smoking) were entered into country‐specific FRAX models to calculate the 10‐year probability of major osteoporotic fractures, with or without femoral neck bone mineral density (BMD). The interaction between probability of a major osteoporotic fracture and treatment efficacy was examined by a Poisson regression. A total of 821 women randomized to placebo and 824 women to abaloparatide‐SC, mean age 69 years in both groups, were followed for up to 2 years. At baseline, the 10‐year probability of major osteoporotic fractures (with BMD) ranged from 2.3% to 57.5% (mean 13.2%). Treatment with abaloparatide‐SC was associated with a 69% (95% confidence interval [CI] 38–85%) decrease in major osteoporotic fracture (MOF) and a 43% (95% CI 9–64%) decrease in any clinical fracture compared with placebo. For all outcomes, hazard ratios tended to decrease (ie, greater efficacy) with increasing fracture probability. Whereas the interaction approached significance for the outcome of any fracture (p = 0.11), there was no statistically significant interaction for any of the fracture outcomes. Similar results were noted when FRAX probability was computed without BMD. Efficacy of abaloparatide‐SC to decrease the risk of major osteoporotic fracture or any clinical fracture in postmenopausal women with low BMD and/or prior fracture appears independent of baseline fracture probability. © 2017 American Society for Bone and Mineral Research.     

FRAX 骨折风险预测工具在新疆地区人群的临床研究

目的评估FRAX骨折风险预测工具在新疆地区人群的适用性研究,并且探讨有、无股骨颈骨密度(BMD)及不同民族对FRAX预测结果的影响。方法选取2012年7月-2013年6月期间在我院就诊的骨质疏松性骨折患者103例(汉族63例,维吾尔族40例)进行回顾性分析。收集所有入选患者FRAX预测工具中所包含的各危险因素资料,将包括股骨颈BMD等数值输入FRAX工具,计算10年内主要部位(包括髋部、脊柱、肱骨及腕部)及髋部骨折的概率进行分析,并且对不同民族及有、无股骨颈BMD情况下FRAX预测值进行比较。结果 103例骨质疏松性骨折患者,未使用BMD未来10年主要部位骨折概率0.9%~14%,髋部骨折概率0%~5.2%;使用BMD未来10年主要部位骨折概率1.2%~26%,髋部骨折概率0%~17%,使用BMD计算的骨折概率与未使用BMD计算的骨折概率之间无统计学意义(P0.05)。不同民族,汉族未来10年主要骨折部位概率1%~26%,髋部骨折概率0%~17%;维吾尔族未来10年主要骨折部位概率0.9%~7%,髋部骨折概率0%~3.4%,汉族与维吾尔族主要部位骨折及髋部骨折概率之间比较有明显差异(P0.01)。结论 FRAX可用于新疆地区人群的骨折风险预测,无BMD情况下的FRAX预测结果同样可靠,维吾尔族人群使用FRAX骨折风险预测的精确性可能低于汉族人群。     

High fracture probability with FRAX® usually indicates densitometric osteoporosis: implications for clinical practice

Summary

Most patients designated as high risk of fracture using fracture risk assessment tool (FRAX^®) with femoral neck bone mineral density (BMD) (i.e., 10-year major osteoporotic fracture probability exceeding 20% or hip fracture exceeding 3%) have one or more T-scores in the osteoporotic range; conversely, almost no high risk patients have normal T-scores at all bone mineral density measurement sites.

Introduction

We determined the agreement between a FRAX^® designation of high risk of fracture [defined as 10-year major osteoporotic fracture probability (≥20%) or hip fracture probability (≥3%)] and the WHO categorizations of bone mineral density according to T-score.

Methods

Ten-year FRAX^® probabilities calculated with femoral neck BMD were derived using both Canadian and US white tools for a large clinical cohort of 36,730 women and 2,873 men age 50 years and older from Manitoba, Canada. Individuals were classified according to FRAX fracture probability and BMD T-scores alone.

Results

Most individuals designated by FRAX as high risk of major osteoporotic fracture had a T-score in the osteoporotic range at one or more BMD measurement sites (85% with Canadian tool and 83% with US white tool). The majority of individuals deemed at high risk of hip fracture had one or more T-scores in the osteoporotic range (66% with Canadian tool and 64% with US white tool). Conversely, there were extremely few individuals (<1%) who were at high risk of major osteoporotic or hip fracture with normal T-scores at all BMD measurement sites.

Conclusions

A FRAX designation of high risk of fracture is usually associated with a densitometric diagnosis of osteoporosis.     

Independent clinical validation of a Canadian FRAX tool: Fracture prediction and model calibration

A FRAX model for Canada was constructed for prediction of osteoporotic and hip fracture risk using national hip fracture data with and without the use of femoral neck bone mineral density (BMD). Performance of this system was assessed independently in a large clinical cohort of 36,730 women and 2873 men from the Manitoba Bone Density Program database that tracks all clinical dual‐energy X‐ray absorptiometry (DXA) test results for the Province of Manitoba, Canada. Linkage with other provincial health databases allowed for the direct comparison of fracture risk estimates from the Canadian FRAX model with observed fracture rates to 10 years (549 individuals with incident hip fractures and 2543 with incident osteoporotic fractures). The 10‐year Kaplan‐Meier estimate for hip fractures in women was 2.7% [95% confidence interval (CI) 2.1–3.4%] with a predicted value of 2.8% for FRAX with BMD, and in men the observed risk was 3.5% (95% CI 0.8–6.2%) with predicted value of 2.9%. The 10‐year estimate of osteoporotic fracture risk for all women was 12.0% (95% CI 10.8–13.4%) with a predicted value of 11.1% for FRAX with BMD, and in men, the observed risk was 10.7% (95% CI 6.6–14.9%) with a predicted value of 8.4%. Discrepancies were observed within some subgroups but generally were small. Fracture discrimination based on receiver operating characteristic curve analysis was comparable with published meta‐analyses with area under the curve for osteoporotic fracture prediction of 0.694 (95% CI 0.684–0.705) for FRAX with BMD and for hip fractures 0.830 (95% CI 0.815–0.846), both of which were better than FRAX without BMD or BMD alone. Individual risk factors considered by FRAX made significant independent contributions to fracture prediction in one or more of the models. In conclusion, a Canadian FRAX tool calibrated on national hip fracture data generates fracture risk predictions that generally are consistent with observed fracture rates across a wide range of risk categories. © 2010 American Society for Bone and Mineral Research.     

Deterioration of Cortical and Trabecular Microstructure Identifies Women With Osteopenia or Normal Bone Mineral Density at Imminent and Long-Term Risk for Fragility Fracture: A Prospective Study

More than 70% of women sustaining fractures have osteopenia or “normal” bone mineral density (BMD). These women remain undetected using the BMD threshold of −2.5 SD for osteoporosis. As microstructural deterioration increases bone fragility disproportionate to the bone loss producing osteopenia/normal BMD, we hypothesized that the structural fragility score (SFS) of ≥70 units, a measure capturing severe cortical and trabecular deterioration, will identify these women. Distal radial images were acquired using high-resolution peripheral quantitative tomography in postmenopausal French women, mean age 67 years (range 42–96 years); 1539 women were followed for 4 years (QUALYOR) and 561 women followed for 8 years (OFELY). Women with osteopenia or normal BMD accounted for ~80% of fractures. Women ≥70 years, 29.2% of the cohort, accounted for 39.2% to 61.5% of fractures depending on follow-up duration. Women having fractures had a higher SFS, lower BMD, and a higher fracture risk assessment score (FRAX) than women remaining fracture-free. In each BMD category (osteoporosis, osteopenia, normal BMD), fracture incidence was two to three times higher in women with SFS ≥70 than <70. In multivariable analyses, associations with fractures remained for BMD and SFS, not FRAX. BMD was no longer, or weakly, associated with fractures after accounting for SFS, whereas SFS remained associated with fracture after accounting for BMD. SFS detected two-to threefold more women having fractures than BMD or FRAX. SFS in women with osteopenia/normal BMD conferred an odds ratio for fracture of 2.69 to 5.19 for women of any age and 4.98 to 12.2 for women ≥70 years. Receiver-operator curve (ROC) analyses showed a significant area under the curve (AUC) for SFS, but not BMD or FRAX for the women ≥70 years of age. Targeting women aged ≥70 years with osteopenia indicated that treating 25% using SFS to allocate treatment conferred a cost-effectiveness ratio < USD $21,000/QALY saved. Quantifying microstructural deterioration complements BMD by identifying women without osteoporosis at imminent and longer-term fracture risk. © 2019 The Authors. Journal of Bone and Mineral Research published by American Society for Bone and Mineral Research.     

FRAX and Risk of Vertebral Fractures: The Fracture Intervention Trial

The validity of the WHO 10‐yr probability of major osteoporotic fracture model (FRAX) for prediction of vertebral fracture has not been tested. We analyzed how well FRAX for major osteoporotic fractures, with and without femoral neck BMD (FN BMD), predicted the risk of vertebral fracture. We also compared the predictive validity of FRAX, FN BMD, and prevalent vertebral fracture detected by radiographs at baseline alone or in combination to predict future vertebral fracture. We analyzed data from the placebo groups of FIT (3.8‐yr follow‐up, n = 3221) with ORs and areas under receiver operating characteristics (ROC) curves (AUC). FRAX with and without FN BMD predicted incident radiographic vertebral fracture. The AUC was significantly greater for FRAX with FN BMD (AUC = 0.71) than FRAX without FN BMD (AUC = 0.68; p = 0.002). Prevalent vertebral fracture plus age and FN BMD (AUC = 0.76) predicted incident radiographic vertebral fracture as well as a combination of prevalent vertebral fracture and FRAX with FN BMD (AUC = 0.75; p = 0.76). However, baseline vertebral fracture status plus age and FN BMD (AUC = 0.76) predicted incident radiographic vertebral fracture significantly better than FRAX with FN BMD (AUC = 0.71; p = 0.0017). FRAX for major osteoporotic fractures (with and without FN BMD) predicts vertebral fracture. However, once FN BMD and age are known, the eight additional risk factors in FRAX do not significantly improve the prediction of vertebral fracture. A combination of baseline radiographic vertebral fracture, FN BMD, and age is the strongest predictor of future vertebral fracture.     

Prediction of Incident Major Osteoporotic and Hip Fractures by Trabecular Bone Score (TBS) and Prevalent Radiographic Vertebral Fracture in Older Men

Trabecular bone score (TBS) has been shown to predict major osteoporotic (clinical vertebral, hip, humerus, and wrist) and hip fractures in postmenopausal women and older men, but the association of TBS with these incident fractures in men independent of prevalent radiographic vertebral fracture is unknown. TBS was estimated on anteroposterior (AP) spine dual‐energy X‐ray absorptiometry (DXA) scans obtained at the baseline visit for 5979 men aged ≥65 years enrolled in the Osteoporotic Fractures in Men (MrOS) Study and its association with incident major osteoporotic and hip fractures estimated with proportional hazards models. Model discrimination was tested with Harrell's C‐statistic and with a categorical net reclassification improvement index, using 10‐year risk cutpoints of 20% for major osteoporotic and 3% for hip fractures. For each standard deviation decrease in TBS, there were hazard ratios of 1.27 (95% confidence interval [CI] 1.17 to 1.39) for major osteoporotic fracture, and 1.20 (95% CI 1.05 to 1.39) for hip fracture, adjusted for FRAX with bone mineral density (BMD) 10‐year fracture risks and prevalent radiographic vertebral fracture. In the same model, those with prevalent radiographic vertebral fracture compared with those without prevalent radiographic vertebral fracture had hazard ratios of 1.92 (95% CI 1.49 to 2.48) for major osteoporotic fracture and 1.86 (95% CI 1.26 to 2.74) for hip fracture. There were improvements of 3.3%, 5.2%, and 6.2%, respectively, of classification of major osteoporotic fracture cases when TBS, prevalent radiographic vertebral fracture status, or both were added to FRAX with BMD and age, with minimal loss of correct classification of non‐cases. Neither TBS nor prevalent radiographic vertebral fracture improved discrimination of hip fracture cases or non‐cases. In conclusion, TBS and prevalent radiographic vertebral fracture are associated with incident major osteoporotic fractures in older men independent of each other and FRAX 10‐year fracture risks, and these data support their use in conjunction with FRAX for fracture risk assessment in older men. © 2015 American Society for Bone and Mineral Research.     

绝经后女性骨折风险与肌源性因子及骨代谢指标的相关性研究

目的 探讨绝经后女性肌源性因子及骨代谢指标与骨质疏松性骨折风险的相关性。方法 研究南京中医药大学无锡附院2021年6月至2022年6月门诊绝经后女性患者215例，根据纳排标准筛选出184例，其中绝经后骨质疏松88例，骨量减少65例，正常骨量31例。收集基线资料、肌骨代谢指标（碱性磷酸酶（ALP）、I型原胶原氨基端前肽（PINP）、鸢尾素（irisin）及肌肉抑制素（MSTN）等）及BMD，应用FRAX评估软件来评估骨折风险。控制年龄、骨量、FRAX风险等级比较肌骨代谢指标、体质指数（BMI）及体表面积（BS）的差异，并对绝经后女性骨折风险和各指标进行相关性分析；多重线性回归分析骨折风险概率与相关变量间的关系。结果 不同年龄组间BMD、PMOF及PHF差异存在统计学意义（P<0.05）；不同骨量组间BMI、BS、ALP、PMOF及PHF差异存在统计学意义（P<0.05）；FRAX不同风险组年龄、BS、BMD、Ca、ALP、PINP、irisin及MSTN之间差异存在统计学意义（P<0.05）；相关性分析显示FRAX骨折概率与年龄、PINP、MSTN成正相关（P<0.05）,与BMI、BS、BMD及irisin成负相关（P<0.05），二元Logistic回归分析显示年龄、PINP与irisin是骨折风险的重要相关因素。结论 基于适合亚洲人群的FRAX干预阈值研究，绝经后女性年龄、PINP与irisin是骨折风险评估的敏感因素，这对优化骨质疏松骨折风险模型有重要意义。     

WHO absolute fracture risk models (FRAX): Do clinical risk factors improve fracture prediction in older women without osteoporosis?

Bone mineral density (BMD) is a strong predictor of fracture, yet most fractures occur in women without osteoporosis by BMD criteria. To improve fracture risk prediction, the World Health Organization recently developed a country‐specific fracture risk index of clinical risk factors (FRAX) that estimates 10‐year probabilities of hip and major osteoporotic fracture. Within differing baseline BMD categories, we evaluated 6252 women aged 65 or older in the Study of Osteoporotic Fractures using FRAX 10‐year probabilities of hip and major osteoporotic fracture (ie, hip, clinical spine, wrist, and humerus) compared with incidence of fractures over 10 years of follow‐up. Overall ability of FRAX to predict fracture risk based on initial BMD T‐score categories (normal, low bone mass, and osteoporosis) was evaluated with receiver‐operating‐characteristic (ROC) analyses using area under the curve (AUC). Over 10 years of follow‐up, 368 women incurred a hip fracture, and 1011 a major osteoporotic fracture. Women with low bone mass represented the majority (n = 3791, 61%); they developed many hip (n = 176, 48%) and major osteoporotic fractures (n = 569, 56%). Among women with normal and low bone mass, FRAX (including BMD) was an overall better predictor of hip fracture risk (AUC = 0.78 and 0.70, respectively) than major osteoporotic fractures (AUC = 0.64 and 0.62). Simpler models (eg, age + prior fracture) had similar AUCs to FRAX, including among women for whom primary prevention is sought (no prior fracture or osteoporosis by BMD). The FRAX and simpler models predict 10‐year risk of incident hip and major osteoporotic fractures in older US women with normal or low bone mass. © 2011 American Society for Bone and Mineral Research     

Effects of risedronate on fracture risk in postmenopausal women with osteopenia

Summary This posthoc analysis of four trials studied the efficacy of risedronate to reduce fragility fractures in postmenopausal women with osteopenia (i.e., T-scores between −1 and −2.5). Risedronate reduced the fracture risk by 73% (p = 0.023) in this population of women with low femoral neck bone mass and no prevalent vertebral fractures. Introduction Low bone mass represents an increasing health risk and burden. Half of fragility fractures occur in osteopenic women underscoring the need for treatments reducing fracture risk. This analysis reports the effect of risedronate to reduce fragility fracture risk in osteopenic women without prevalent vertebral fractures. Methods Postmenopausal women with osteopenia, defined as femoral neck T-score between −1 and −2.5 by DXA and no prevalent vertebral fractures, were identified from four controlled randomized trials (BMD Multinational, BMD North America, VERT Multinational and VERT North America). The risk reduction for fragility fractures in patients receiving 5 mg risedronate daily for 1.5 to 3 years compared to placebo was assessed. An additional sensitivity analysis excluded patients who were osteopenic at the femoral neck but had a BMD lower than −2.5 SD at the lumbar spine. Results Six hundred and twenty postmenopausal women with osteopenia were included, receiving either placebo (n = 309) or risedronate 5 mg (n = 311). Risedronate reduced the risk of fragility fractures by 73% over 3 years versus placebo (p = 0.023); cumulative fragility fracture incidence was 6.9% in placebo-treated versus 2.2% in risedronate-treated patients. The magnitude of the effect was similar in the sensitivity analysis subset. Conclusion Risedronate significantly reduced the risk of fragility fractures in postmenopausal women with osteopenia (femoral neck T-score between −1 and −2.5 SD) and no prevalent vertebral fractures.