FRAX-derived intervention and assessment thresholds for osteoporosis in ten Middle Eastern countries.

This study established FRAX-based age-specific assessment and intervention thresholds for ten Middle Eastern countries where FRAX is currently available, but the lack of specific thresholds has limited its usefulness. The intervention thresholds ranged from 0.6 (Saudi Arabia) to 36.0% (Syria) at the ages of 40 and 90 years, respectively. INTRODUCTION: Developing fracture risk assessment tools allows physicians to select patients for therapy based on their absolute fracture risk instead of relying solely on bone mineral density (BMD). The most widely used tool is FRAX, currently available in ten Middle Eastern countries. This study aimed to set FRAX-derived assessment and intervention thresholds for individuals aged 40 or above in ten Middle Eastern countries. METHODS: The age-specific 10-year probabilities of a major osteoporotic fracture (MOF) for a woman with a BMI of 25.0 kg/m2, without BMD and clinical risk factors except for prior fracture, were calculated as intervention Threshold (IT). The upper and lower assessment thresholds were set at 1.2 times the IT and an age-specific 10-year probability of a MOF in a woman with a BMI of 25.0 kg/m2, without BMD, prior fracture, and other clinical risk factors, respectively. IT is utilized to determine treatment or reassurance when BMD facilities are unavailable. However, with BMD facilities, assessment thresholds can offer treatment, reassurance, or bone densitometry based on MOF probability. RESULTS: The age-specific IT varied from 0.9 to 11.0% in Abu Dhabi, 2.9 to 10% in Egypt, 2.7 to 14.0% in Iran, 1.0 to 28.0% in Jordan, 2.7 to 27.0% in Kuwait, 0.9 to 35.0% in Lebanon, 1.0 to 16.0% in Palestine, 4.1 to 14% in Qatar, 0.6 to 3.7% in Saudi Arabia, and 0.9 to 36.0% in Syria at the age of 40 and 90 years, respectively. CONCLUSIONS: FRAX-based IT in Middle Eastern countries provides an opportunity to identify individuals with high fracture risk.

FRAX-based intervention thresholds in eight Eurasian countries: Armenia, Belarus, Georgia, Kazakhstan, the Kyrgyz Republic, Moldova, the Russian Federation, and Uzbekistan.

Age-specific intervention and assessment thresholds based on FRAX® were developed for eight Eurasian countries participating in the EVA study (Armenia, Belarus, Georgia, Moldova, Kazakhstan, the Kyrgyz Republic, the Russian Federation, and Uzbekistan). The intervention thresholds (major osteoporotic fracture) ranged from 3.6 (Armenia and Georgia) to 12.3% (Uzbekistan) for people at age 50 years, and from 16 (Armenia) to 27% (Belarus) at the age of 90 years. These thresholds enable a substantial advance in the ease of detection of individuals at high fracture risk. INTRODUCTION: The purpose of this study was to derive and compare FRAX-based intervention and BMD assessment thresholds for 8 Eurasian countries in the EVA study. METHODS: The intervention threshold (IT) was set at a 10-year probability of a major osteoporotic fracture (MOF), calculated without BMD, equivalent to a woman with a prior fragility fracture but no other clinical risk factors, and a body mass index (BMI) of 25.0 kg/m2. The lower assessment threshold was set at a 10-year probability of a MOF in women with BMI of 25.0 kg/m2, without previous fracture or other clinical risk factors. The upper assessment threshold was set at 1.2 times the IT. RESULTS: The age-specific intervention thresholds ranged from 3.6 (Armenia and Georgia) to 12.3% (Uzbekistan) for men and women at the age of 50 years and from 16 (Armenia) to 27% (Belarus) at the age of 90 years. The difference between countries was most evident at younger ages and become progressively less with advancing age. CONCLUSIONS: For the 8 Eurasian countries, the newly established FRAX-based intervention thresholds provide an opportunity to improve the clinical detection of both men and women with a high risk of fracture and improve treatment rates.

Comparison of the Osteoporosis Self-Assessment Tool for Asians and the fracture risk assessment tool - FRAX to identify densitometric defined osteoporosis: A discriminatory value analysis in a multi-ethnic female population in Southeast Asia.

OBJECTIVES: The accuracy of FRAX® as a screening tool to identify osteoporosis and how it compares with tools such as Osteoporosis Self-Assessment Tool for Asians (OSTA), in Southeast Asian women has so far been unexplored. We aimed to determine the FRAX® thresholds that accurately identify densitometric osteoporosis and to compare its performance with that of OSTA for this purpose. METHODS: Singaporean postmenopausal women (n = 1056) were evaluated. FRAX® Major Osteoporotic Fracture Probability (MOFP), Hip Fracture Probability (HFP) scores, and OSTA indices were calculated. Receiver operating characteristic (ROC) curves were constructed and via the Youden index, the optimal cut-off points of balanced sensitivity and specificity for dual energy X-ray absorptiometry (DXA)-defined osteoporosis were identified and the performance characteristics were compared. RESULTS: A FRAX® MOFP threshold of ≥3.7% had sensitivity, specificity, positive predictive value and negative predictive value of 0.78 (0.73-0.83), 0.63 (0.59-0.66), 0.4 (0.36-0.44), and 0.9 (0.87-0.92), respectively in identifying osteoporosis. The corresponding values for a HFP threshold of ≥0.6% were 0.85 (0.80-0.89), 0.58 (0.55-0.62), 0.39 (0.35-0.43), and 0.92 (0.9-0.94) and that for an OSTA index cut-off of ≤ -1.2 were 0.76 (0.70-0.81), 0.74 (0.71-0.77), 0.48 (0.43-0.54), and 0.91 (0.88-0.93). The area under the ROC curves were 82.8% (79.9%-85.6%), 77.6% (74.2%-81%), and 79.6% (76.5%-82.8%) for OSTA, MOFP, and HFP thresholds respectively. CONCLUSIONS: FRAX® and OSTA perform comparably in identifying osteoporosis in our population. OSTA has only 2 parameters and may be simpler to use. However, FRAX® may also have a role in primary screening to identify the postmenopausal woman to be referred for DXA scanning and may help facilitate fracture risk reduction discussions with the patient.

Analysis of dosimetric verification results of stereotactic body radiotherapy / 中华放射医学与防护杂志

Objective To analyze the patient-specific dosimetric verification result of stereotactic body radiotherapy ( SBRT ) plans, and to investigate the sensitivity of the result to three factors:interpolation of measured data, size of dose calculation grid and assessment threshold. Methods The dosimetric verification results of SBRT plans of 50 patients were retrospectively analyzed to evaluate the impact of the following factors. The linear interpolation ( 1. 00 mm) and non-interpolation ( 7. 62 mm) were applied to measured data respectively. Three dose calculation grid sizes of Eclipse planning system, i.e., 1. 0 mm, 2. 5 mm and 4. 0 mm were compared respectively. The threshold of dose assessment was selected as 10％, 20％ and 30％, respectively. Three criteria of γ analysis were selected: 2％/2 mm, 3％/2 mm and 3％/3 mm. Results Under criteria of 2％/2 mm, 3％/2 mm and 3％/3 mm, the average γ passing rates were (86. 3±7. 3)％ and (93. 7±5. 6)％, (94. 1±4. 4)％ and(97. 7±3. 9)％, (97. 7 ±2. 2)％ and (99. 1±1. 7)％, respectively, with and without linear interpolation. Relative to the 1. 0 mm reference grid, the grids of 2. 5 mm and 4. 0 mm significantly decreased γ passing rates by 3. 8％, 1. 9％, 0. 8％ ( t=8. 41, 9. 06, 5. 30, P<0. 05) and by 6. 5％, 6. 0％, 3. 5％ ( t=-13. 76, -13. 15, -9. 80, P<0. 05) under criteria of 2％/2 mm, 3％/2 mm and 3％/3 mm, respectively. Relative to the 10％ reference threshold, the shresholds of 20％ and 30％ significantly decreasedγpassing rates by 2. 4％, 1. 0％, 0. 6％(t=-8. 60, -5. 86, -4. 68, P<0. 05) and by 4. 0％, 1. 7％, 0. 9％ (t=-9. 45, -6. 66, -5. 06, P<0. 05) under criteria of 2％/2 mm, 3％/2 mm and 3％/3 mm, respectively. Conclusions Interpolation, dose calculation grid size and dose assessment threshold are influential factors of dose verification result, and need to be considered during dosimetric verification of stereotactic radiotherapy patients.

Analysis of dosimetric verification results of stereotactic body radiotherapy / 中华放射医学与防护杂志

Objective@#To analyze the patient-specific dosimetric verification result of stereotactic body radiotherapy (SBRT) plans, and to investigate the sensitivity of the result to three factors: interpolation of measured data, size of dose calculation grid and assessment threshold.@*Methods@#The dosimetric verification results of SBRT plans of 50 patients were retrospectively analyzed to evaluate the impact of the following factors. The linear interpolation (1.00 mm) and non-interpolation (7.62 mm) were applied to measured data respectively. Three dose calculation grid sizes of Eclipse planning system, i. e., 1.0 mm, 2.5 mm and 4.0 mm were compared respectively. The threshold of dose assessment was selected as 10%, 20% and 30%, respectively. Three criteria of γ analysis were selected: 2%/2 mm, 3%/2 mm and 3%/3 mm.@*Results@#Under criteria of 2%/2 mm, 3%/2 mm and 3%/3 mm, the average γ passing rates were (86.3±7.3)% and (93.7±5.6)%, (94.1±4.4)% and(97.7±3.9)%, (97.7 ±2.2)% and (99.1±1.7)%, respectively, with and without linear interpolation. Relative to the 1.0 mm reference grid, the grids of 2.5 mm and 4.0 mm significantly decreased γ passing rates by 3.8%, 1.9%, 0.8% (t=8.41, 9.06, 5.30, P<0.05) and by 6.5%, 6.0%, 3.5% (t=-13.76, -13.15, -9.80, P<0.05) under criteria of 2%/2 mm, 3%/2 mm and 3%/3 mm, respectively. Relative to the 10% reference threshold, the shresholds of 20% and 30% significantly decreased γ passing rates by 2.4%, 1.0%, 0.6%(t=-8.60, -5.86, -4.68, P<0.05) and by 4.0%, 1.7%, 0.9% (t=-9.45, -6.66, -5.06, P<0.05) under criteria of 2%/2 mm, 3%/2 mm and 3%/3 mm, respectively.@*Conclusions@#Interpolation, dose calculation grid size and dose assessment threshold are influential factors of dose verification result, and need to be considered during dosimetric verification of stereotactic radiotherapy patients.