Outcomes of applying the NOF, NOGG and Taiwanese guidelines to a cohort of Chinese early postmenopausal women

Establishment of a preliminary FRAX®-based intervention threshold for rheumatoid arthritis–associated fragility fracture: a 3-year longitudinal, observational, cohort study

Background:

To establish a FRAX®-based prediction model for rheumatoid arthritis (RA)-associated fragility fracture.

Methods:

This study is a longitudinal, real-world, registry cohort study. Patients with RA were registered to start in September 2014. The baseline demographics, bone mineral density (BMD), and risk factors of osteoporosis or fragility fracture were recorded. Subsequent fragility fractures during the 3-year observation period were also recorded. We developed a fixed intervention threshold (FITD) to identify fractures by choosing an optimal cut-off point on the receiver operating characteristic (ROC) curve and FRAX®. Several models for intervention thresholds (IT), including fixed intervention threshold (Taiwan) (FITT), age-specific individual intervention threshold (IIT), and hybrid intervention threshold (HIT), were compared to evaluate which IT model will have better discriminative power.

Results:

As of December 2020, a total of 493 RA participants have completed the 3-year observation study. The mean age of the participants was 59.3 ± 8.7, and 116 (23.5%) new fragility fractures were observed during the study period. In terms of pairwise comparisons of area under the curve ( n, 95% confidence interval) in the ROC curve, the FITD (0.669, 0.610–0.727, p < 0.001) with a value of 22% in major osteoporotic fracture and FITT (0.640, 0.582–0.699, p < 0.001) is significantly better than reference, but not for IIT (0.543, 0.485–0.601, p = 0.165) and HIT (0.543, 0.485–0.601, p = 0.165).

Conclusion:

An optimal FIT is established for intervention decisions in RA-associated fragility fractures. This model can offer an easy and simple guide to aid RA caregivers to provide interventions to prevent fragility fractures in patients with RA.

Validation of the Taiwan FRAX® calculator for the prediction of fracture risk

The Taiwan FRAX® calculator was validated to predict incident fractures preliminarily. Cutoffs of FRAX probability for predicting major osteoporotic fracture and hip fracture were proposed as 9.5% and 4% in Taiwanese individuals.

PURPOSE

FRAX® is an algorithm used to calculate fracture probabilities based on clinical risk factors (CRFs) and bone mineral density (BMD). The country-specific Taiwan FRAX calculator has not been validated since its establishment in 2010. The aim of the present study is to evaluate the predictive performance of the Taiwan FRAX calculator using longitudinal fracture data.

METHODS

A total of 1975 subjects, aged ≧ 40 years old, from Yunlin and Tianliao cohorts in Taiwan during the period 2009-2010, were identified and completely connected with the 2008-2016 National Health Insurance Research Database.

RESULTS

During the average 6.8 ± 1.1 years of follow-up, 160 incident major osteoporotic fractures (MOFs) were identified. The predictive ability assessing based on the observed to expected fractures (O/E) ratio calculated with the FRAX probability adjusted for 6.8 years were 1.19 (95%CI 1.02-1.39) for MOF, and 1.07 (95%CI 0.82-1.39) for hip fractures. In the discriminative statistics, the AUC for prediction of major osteoporotic fractures using FRAX was 0.75 without and 0.77 with BMD (AUC for hip fracture was 0.75 without and 0.77 with BMD). The optimal cutoff value was 9.5% of the FRAX score with BMD for all major osteoporotic fractures, with good sensitivity (76.9%) and specificity (65.3%). For hip fractures, the optimal cutoff point for the FRAX probability with BMD was 4.0%, and the sensitivity and specificity were 74.4% and 68.3%, respectively.

CONCLUSION

The Taiwan FRAX® calculator was validated to predict incident fractures preliminarily. Cutoffs are proposed for predicting fracture risk in Taiwanese individuals.

Comparison of the NOF and NOGG guidelines for spinal radiographic examination in postmenopausal Chinese women

The aim was to compare the National Osteoporosis Foundation (NOF) and the UK National Osteoporosis Guideline Group (NOGG) guidelines for the detection of vertebral fractures in postmenopausal Chinese women. The NOF guidelines had higher accuracy than the UK guidelines for spinal radiography examination.

PURPOSE

To compare the National Osteoporosis Foundation (NOF) and the UK National Osteoporosis Guideline Group (NOGG) guidelines for the detection of vertebral fractures in postmenopausal Chinese women.

METHODS

A cross-sectional study on 255 community-dwelling postmenopausal women was conducted in Hunan province in 2017. Demographic and clinical characteristics and risk factors were recorded through questionnaires. Height and weight were measured using standard methods, and bone mineral density (BMD) was measured with dual-energy X-ray absorptiometry. Vertebral fractures were diagnosed by radiography using semi-quantitative morphometry.

RESULTS

The prevalence of vertebral fractures was 9.4%. Women with vertebral fractures were significantly older and shorter, had higher years-since menopause and height loss values and lower BMD and T-scores at the femoral neck and total hip, and were more likely to have a history of previous fractures. The sensitivity and specificity of the NOF guidelines were 91.7% and 39.8%, respectively, while the NOGG guidelines had lower sensitivity (87.5%) and specificity (32.5%). However, a higher percentage had indications for radiography in the 50-64 years age group according to the NOGG guidelines, while a higher percentage had indications for radiography in the ≥ 65 year group according to the NOF guidelines.

CONCLUSIONS

The NOF guidelines were better than the NOGG guidelines for spinal radiography examination in the Chinese postmenopausal women.

Novel algorithm generating strategy to identify high fracture risk population using a hybrid intervention threshold

INTRODUCTION

The aim of this study was to develop an algorithm to identify high-risk populations of fragility fractures in Taiwan.

MATERIALS AND METHODS

A total of 16,539 postmenopausal women and men (age ≥ 50 years) were identified from the Taiwan Osteoporosis Survey database. Using the Taiwan FRAX^® tool, the 10-year probability of major osteoporotic fracture (MOF) and hip fracture (HF) and the individual intervention threshold (IIT) of each participant were calculated. Subjects with either a probability above the IIT or those with MOF ≥ 20% or HF ≥ 9% were included as group A. Subjects with a bone mineral density (BMD) T-score at femoral neck based on healthy subjects of ≤ - 2.5 were included in group B. We tested several cutoff points for MOF and HF so that the number of patients in group A and group B were similar. A novel country-specific hybrid intervention threshold along with an algorithm was generated to identify high fracture risk individuals.

RESULTS

3173 (19.2%) and 3129 (18.9%) participants were categorized to groups A and B, respectively. Participants in group B had a significantly lower BMD (p < 0.001), but clinical characteristics, especially the 10-year probability of MOF (p < 0.001) or HF (p < 0.001), were significantly worse in group A. We found the algorithm generated from the hybrid intervention threshold is practical.

CONCLUSION

The strategy of generating an algorithm for fracture prevention by novel hybrid intervention threshold is more efficient as it identifies patients with a higher risk of fragility fracture and could be a template for other country-specific policies.

Agreement between the Turkey Guidelines and the Fracture Risk Assessment Tool®-based Intervention Threshold

BACKGROUND

The aim of this study was to evaluate the agreement between the fracture-risk assessment tool (FRAX®)-based intervention strategy in Turkey and the recommendations published in the Healthcare Practices Statement (HPS).

METHODS

This descriptive cross-sectional study included individuals aged 40 to 90 years who were previously diagnosed as having osteoporosis but had not received any treatment. The intervention thresholds recommended by the National Osteoporosis Foundation for treatment were used. The criteria necessary for the start of administration of pharmacological agents in osteoporosis treatment were evaluated on the basis of the HPS guidelines.

RESULTS

Of the 1,255 patients evaluated, 161 (12.8%) were male and 1,094 (87.2%) were female. In the evaluation, according to HPS, treatment was recommended for 783 patients (62.4%; HPS+) and not recommended for 472 (37.6%; HPS-). Of the 783 HPS+ patients, 391 (49.9%) were FRAX+, and of the 472 HPS- patients, 449 (95.1%) were FRAX-. A statistically significant difference was observed between the treatment recommendations of HPS and FRAX® (P<0.001). In the age group of 75 to 90 years, excellent agreement was found between the two strategies (Gwet's agreement coefficient 1=0.94). As age increased, the agreement between the two treatment strategies also increased.

CONCLUSIONS

The FRAX® model has different treatment recommendation rates from the HPS. The agreement between the two is at a minimal level. However, as age increased, so did the agreement between the FRAX® and the HPS treatment recommendations. In the recommendation to start pharmacological treatment primarily based on age, non-medical interventions that preserve bone density should be evaluated.

Impact of FRAX-based osteoporosis intervention using real world data

OBJECTIVES

To estimate the implications and accuracy of the most common fracture prevention strategies: (1) fixed threshold by the National Osteoporosis Foundation (NOF), (2) age-dependent threshold by the National Osteoporosis Guideline Group (NOGG) and (3) osteoporotic bone mineral density (BMD).

METHODS

A retrospective cohort of all 50-90years old female members in a nationally representative payer provider healthcare organization in Israel, with 10years of follow-up on incident events of major osteoporotic fractures. Since events are less frequent than non-events, balanced accuracy (the average between the accuracy obtained for patients with and without events) was used to measure performance.

RESULTS

Overall among 141,320 women NOF and NOGG would recommend therapy for 17.3% and 2.8% respectively, with NOF exhibiting higher balanced accuracy: 74.1% vs. 54.2% for incident hip fractures detection and 60.0% vs. 51.6% for a composite outcome of major osteoporotic fractures. In patients with available BMD (n=16,578) the treatment intervention criteria of NOF, NOGG, osteoporotic femur neck or vertebral BMD were met by 30.5%, 9.3% and 24.6% of the population, with balanced accuracy of 70.1%, 56.5% and 62.3% respectively for hip fractures and 61.4%, 52.8%, 58.1% for major osteoporotic fractures. At the age of 75years or older the NOF hip fracture risk threshold (3%) was exceeded in most women regardless of risk factors other than age.

CONCLUSIONS

In this large population-based study, detection of patients at high risk of sustaining a major osteoporotic fracture within 10 years was more accurate with the NOF fixed threshold criteria as compared with the age-varying NOGG or BMD-only. However, special consideration and further studies are warranted in patients aged 75years or older with preserved bone density, which may benefit from non-medicinal interventions.

The FRAX-based Lebanese osteoporosis treatment guidelines: rationale for a hybrid model

We describe our approach to develop FRAX-based osteoporosis treatment guidelines in Lebanon, a country with low-moderate fracture rates. A hybrid assessment algorithm that combines a fixed 10 % intervention threshold until age 70 years, and an age-dependent threshold thereafter, was deemed most suitable.

INTRODUCTION

The FRAX risk calculator is used to guide intervention thresholds in several national osteoporosis guidelines. This study aimed to describe the approach in developing FRAX-based osteoporosis treatment guidelines in Lebanon, a country with relatively low fracture rates.

METHODS

We reassessed previous national guidelines combined with an evaluation of age-dependent and fixed FRAX-based intervention threshold models used in the UK, the USA, and Canada. We took into consideration the risk for major osteoporotic fractures (MOF) and the proportions of subjects considered for therapy using such thresholds, before finalizing a model for Lebanon.

RESULTS

The new Lebanese guidelines retained the recommendation to treat individuals with fragility fracture at the hip or spine. A femoral neck T-score ≤-2.5 in subjects without fractures was dropped, since it would imply consideration of therapy for individuals with a 10-year risk for MOF of <10 %, up to age 75 years in women. After considering the impact of both age-dependent and fixed intervention thresholds, we chose a new hybrid algorithm, combining a fixed 10 % treatment threshold until age 70 years and an age-dependent threshold thereafter.

CONCLUSION

The Lebanese FRAX-based hybrid model takes into consideration the risk for MOF and the proportions of subjects considered for treatment. This model avoids consideration of drug therapy in a large proportion of younger subjects at low risk for fracture and targets high risk elderly individuals. It was deemed most suitable for Lebanon and may be an option for other countries with relatively low fracture rates.

A systematic review of intervention thresholds based on FRAX : A report prepared for the National Osteoporosis Guideline Group and the International Osteoporosis Foundation

This systematic review identified assessment guidelines for osteoporosis that incorporate FRAX. The rationale for intervention thresholds is given in a minority of papers. Intervention thresholds (fixed or age-dependent) need to be country-specific.

INTRODUCTION

In most assessment guidelines, treatment for osteoporosis is recommended in individuals with prior fragility fractures, especially fractures at spine and hip. However, for those without prior fractures, the intervention thresholds can be derived using different methods. The aim of this report was to undertake a systematic review of the available information on the use of FRAX® in assessment guidelines, in particular the setting of thresholds and their validation.

METHODS

We identified 120 guidelines or academic papers that incorporated FRAX of which 38 provided no clear statement on how the fracture probabilities derived are to be used in decision-making in clinical practice. The remainder recommended a fixed intervention threshold (n = 58), most commonly as a component of more complex guidance (e.g. bone mineral density (BMD) thresholds) or an age-dependent threshold (n = 22). Two guidelines have adopted both age-dependent and fixed thresholds.

RESULTS

Fixed probability thresholds have ranged from 4 to 20 % for a major fracture and 1.3-5 % for hip fracture. More than one half (39) of the 58 publications identified utilised a threshold probability of 20 % for a major osteoporotic fracture, many of which also mention a hip fracture probability of 3 % as an alternative intervention threshold. In nearly all instances, no rationale is provided other than that this was the threshold used by the National Osteoporosis Foundation of the USA. Where undertaken, fixed probability thresholds have been determined from tests of discrimination (Hong Kong), health economic assessment (USA, Switzerland), to match the prevalence of osteoporosis (China) or to align with pre-existing guidelines or reimbursement criteria (Japan, Poland). Age-dependent intervention thresholds, first developed by the National Osteoporosis Guideline Group (NOGG), are based on the rationale that if a woman with a prior fragility fracture is eligible for treatment, then, at any given age, a man or woman with the same fracture probability but in the absence of a previous fracture (i.e. at the 'fracture threshold') should also be eligible. Under current NOGG guidelines, based on age-dependent 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 using a hybrid model reduces this disparity.

CONCLUSION

The use of FRAX (fixed or age-dependent thresholds) as the gateway to assessment identifies individuals at high risk more effectively than the use of BMD. However, the setting of intervention thresholds needs to be country-specific.