University of Manitoba, Winnipeg, Canada.
McGill University, Montreal, Canada.
Osteoporos Int. 2021 Jan;32(1):113-122. doi: 10.1007/s00198-020-05594-8. Epub 2020 Aug 18.
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.
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.
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.
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).
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.
我们发现加拿大 FRAX®工具在不同种族间的校准存在较大差异，该工具严重高估了亚洲女性和黑人女性的主要骨质疏松性骨折（MOF）风险，以及亚洲女性的髋部骨折风险。
FRAX®是根据特定人群的骨折和死亡率数据进行校准的。FRAX 是否需要适应一个国家内的种族多样性尚不确定。我们使用基于人群的马尼托巴省骨密度（BMD）计划登记处和自我报告的种族来解决这个问题。
研究人群为年龄在 40 岁或以上、基线时有 FRAX 评估（加拿大和其他种族计算器）、骨折结局和自我报告种族的女性（白人 N=68907[参考]、亚洲人 N=1910、黑人 N=356）。使用调整后的危险比（HR）和 95%置信区间（CI）估计 MOF 和髋部骨折的时间。我们检查了 DXA 中可能导致种族差异的候选变量，包括骨骼大小、髋关节轴长（HAL）、骨小梁评分（TBS）和估计的身体成分。
在使用 BMD 对加拿大 FRAX 工具进行基线风险调整后，与白人女性相比，亚洲女性发生 MOF 的风险要低得多（HR 0.46，95%CI 0.35-0.59）和髋部骨折（0.16，95%CI 0.08-0.34）。黑人女性发生 MOF 的风险也较低（HR 0.58，95%CI 0.32-1.00）；没有髋部骨折。美国特定种族的 FRAX 计算器解释了 MOF 风险中大部分种族间差异（亚洲人 86%，黑人 92%），但仅部分解释了亚洲女性髋部骨折风险较低的原因（40%）。候选变量仅解释了种族影响的一小部分。分析中的风险梯度相似（p-交互作用种族*FRAX 不显著）。
我们发现加拿大 FRAX 工具在骨折概率方面存在显著的种族差异，亚洲和黑人女性的骨折概率被高估。美国的种族计算器有助于解决 MOF 风险评估中的这一差异，但不能解决亚洲女性髋部骨折风险的问题。
