Cadarette S M, Jaglal S B, Kreiger N, McIsaac W J, Darlington G A, Tu J V
Canadian Multicentre Osteoporosis Study, University of Toronto, Ont.
CMAJ. 2000 May 2;162(9):1289-94.
Although mass screening for osteoporosis is not recommended among postmenopausal women, there is no consensus on which women should undergo testing for low bone mineral density. The objective of this study was to develop and validate a clinical tool to help clinicians identify which women are at increased risk for osteoporosis and should therefore undergo further testing with bone densitometry.
Using Ontario baseline data from the Canadian Multicentre Osteoporosis Study, we identified all cognitively normal women aged 45 years or more who had undergone testing with dual-energy x-ray absorptiometry (DXA) at both the femoral neck and the lumbar spine (L1-L4). Participants who had a previous diagnosis of osteoporosis or were taking bone active medication other than ovarian hormones were excluded. The main outcome measure was low bone mineral density (T score of 2 or more standard deviations below the mean for young Canadian women) at either the femoral neck or the lumbar spine. Logistic regression analysis and receiver operating characteristic (ROC) analysis were used to identify the simplest algorithm that would identify women at increased risk for low bone mineral density.
The study population comprised 1376 women, of whom 926 were allocated to the development of the tool and 450 to its validation. A simple algorithm based on age, weight and current estrogen use (yes or no) was developed. Validation of this 3-item Osteoporosis Risk Assessment Instrument (ORAI) showed that the tool had a sensitivity of 93.3% (95% confidence interval [CI] 86.3%-97.0%) and a specificity of 46.4% (95% CI 41.0%-51.8%) for selecting women with low bone mineral density. The sensitivity of the instrument for selecting women with osteoporosis was 94.4% (95% CI 83.7%-98.6%). Use of the ORAI represented a 38.7% reduction in DXA testing compared with screening all women in our study.
The ORAI accurately identifies the vast majority of women likely to have low bone mineral density and is effective in substantially decreasing the need for all women to undergo DXA testing.
尽管不建议对绝经后女性进行骨质疏松症的大规模筛查，但对于哪些女性应接受低骨密度检测尚无共识。本研究的目的是开发并验证一种临床工具，以帮助临床医生识别哪些女性骨质疏松风险增加，因此应接受骨密度测定的进一步检测。
利用加拿大多中心骨质疏松症研究的安大略省基线数据，我们确定了所有年龄在45岁及以上、认知正常、在股骨颈和腰椎（L1-L4）均接受过双能X线吸收法（DXA）检测的女性。排除既往诊断为骨质疏松症或正在服用除卵巢激素以外的骨活性药物的参与者。主要结局指标是股骨颈或腰椎的低骨密度（T值低于年轻加拿大女性平均值2个或更多标准差）。采用逻辑回归分析和受试者工作特征（ROC）分析来确定能够识别低骨密度风险增加女性的最简单算法。
研究人群包括1376名女性，其中926名被分配用于工具开发，450名用于验证。基于年龄、体重和当前雌激素使用情况（是或否）开发了一种简单算法。对这种三项骨质疏松症风险评估工具（ORAI）的验证表明，该工具在选择低骨密度女性时的敏感性为93.3%（置信区间[CI]95% 86.3%-97.0%），特异性为46.4%（95% CI 41.0%-51.8%）。该工具在选择骨质疏松症女性时的敏感性为94.4%（95% CI 83.7%-98.6%）。与对我们研究中的所有女性进行筛查相比，使用ORAI可使DXA检测减少38.7%。
ORAI能够准确识别绝大多数可能存在低骨密度的女性，并有效大幅减少所有女性接受DXA检测的需求。
