骨折风险评估工具FRAX对藏族患者临床应用价值的探讨

The clinic value of FRAX in Tibetans patients

目的对行DXA检查的藏族、汉族患者同时行FRAX骨折风险预测评估,比较DXA检查提示骨质疏松检出率及FRAX评估提示高骨折风险率在藏汉两族患者间检出的差异;探讨FRAX骨折风险预测工具应用于藏族骨质疏松患者的临床价值。方法选取2017年9～10月到我院骨密度室行DXA检查的患者252例(藏族128例,汉族124例),对上述患者进行FRAX评估,估算其未来10年主要部位骨折风险、髋部骨折风险(使用中国香港测评系统, https://www.sheffield.ac.uk/FRAX/)。采用SPSS 19.0统计软件,正态性分布的计量资料以均数±标准差表示,非正态分布计量以中位数和四分间距位表示。组间比较独立样本t检验;诊断能力的评价指标用敏感性、特异性、Youden index表示。结果藏族患者平均DXA T/Z值水平高于汉族,但二者髋部骨折风险、主要部位骨折风险均无明显区别。藏族患者FRAX未来10年髋部主要骨折风险≥3%为治疗阈值时Youden index=0.4465。以主要部位骨折概率≥20%作为诊断标准时在藏族患者中敏感性为16.67%,在汉族患者中敏感性为12.5%,以髋部骨折风险概率≥3%,在藏族患者中敏感性为55.56%,在汉族患者中敏感性为37.5%。FRAX在评估藏族、汉族患者髋部及主要骨折部位骨折风险时,以主要部位骨折概率≥20%作为诊断标准,在藏、汉两族患者中特异性均为100%。以髋部骨折风险概率≥3%,在藏族患者中特异性为89.09%,在汉族患者中特异性为92%。结论 FRAX对于藏族患者骨折风险有较好的评估效能,使用未来10年髋部主要骨折风险≥3%为治疗阈值有较高的临床价值。在部分贫困藏区,当临床医生通过FRAX评估出高骨折风险(FRAX-M≥20%,FRAX-H≥3%)时,建议积极将患者转诊至上级医院进行及时诊疗。

Objective Based on BMD measured using DXA and 10-year probability of hip fracture and major osteoporotic fracture estimated using FRAX,to compare the differences in the detection of osteoporosis by DXA and high fracture risk by FRAX between Tibetans and Han Chinese patients,and to discuss whether FRAX has good clinic value in Tibetans patients.Methods FRAX questionnaires were distributed to 252 subjects(124 Han Chinese and 128 Tibetan patients)who underwent DXA from September to October 2017 at Hospital of Chengdu Office of People’s Government of Tibetan.We used FRAX calculation tool of Hong Kong to predict their 10-year fracture risk(http://www.shefgield.ac.uk/FRAX/).SPSS19.0 was used for the statistical analysis,normal distribution data are showed as mean and standard deviation,data not of normal distribution were represented by median and interquartile range,and t test was used for the comparison of independent samples between groups.Sensitivity,specificity and Youden index were calculated to assess the diagnostic efficiency.Results The average DXA T/Z scores of Tibetan patients was higher than Han Chinese patients,however there was no significant difference in the probability of osteoporotic fracture between them.When the 10-year probability of hip fracture≥3% was used as the threshold of clinical treatment in Tibetans patients,Youden index=0.4465.When the 10-year probability of major fracture≥20% was used as the threshold of clinical treatment,the sensitivity of was 16.67% for Tibetans and 12.5% for Han Chinese patients.When the 10-year probability of hip fracture≥3% was used as the threshold of clinical treatment,the sensitivity of was 55.56% for Tibetans and 37.5% for Han Chinese patients.When the 10-year probability of major fracture≥20% was used as the threshold of clinical treatment,the specificity was 100% for both Tibetans and Han Chinese patients.When the 10-year probability of hip fracture≥3% was used as the threshold of clinical treatment,the specificity of was 89.09% for Tibetans and 92% for Han Chinese patients.Conclusion FRAX is a useful clinical tool in evaluating fracture risk for Tibetans patients,especially when we use the 10-year probability of hip fracture≥3% as the treatment threshold.A patient who live in disadvantaged parts in Tibetan area with a high risk of fracture(FRAX-M≥20% or FRAX-H≥3%)should be referred to a superior hospital for timely diagnosis and treatment.