Nüesch Eveline, Pablo Perel, Dale Caroline E, Prieto-Merino David, Kumari Meena, Bowling Ann, Ebrahim Shah, Casas Juan P
Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, UK.
Institute of Epidemiology and Health, University College London, London, UK.
Age Ageing. 2015 Mar;44(2):275-82. doi: 10.1093/ageing/afu159. Epub 2014 Oct 27.
To develop and validate a prediction model for incident locomotor disability after 7 years in older adults.
Prospective British cohort studies: British Women's Heart and Health Study (BWHHS) for development and the English Longitudinal Study of Ageing (ELSA) for validation.
Community-dwelling older adults.
Multivariable logistic regression models after selection of predictors with backward elimination. Model performance was assessed using metrics of discrimination and calibration. Models were internally and externally validated.
Locomotor disability was reported in BWHHS by 861 of 1,786 (48%) women after 7 years. Age, a history of arthritis and low physical activity levels were the most important predictors of locomotor disability. Models using routine measures as predictors had satisfactory calibration and discrimination (c-index 0.73). Addition of 31 blood markers did not increase the predictive performance. External validation in ELSA showed reduced discrimination (c-index 0.65) and an underestimation of disability risks. A web-based calculator for locomotor disability is available (http://www.sealedenvelope.com/trials/bwhhsmodel/).
We developed and externally validated a prediction model for incident locomotor disability in older adults based on routine measures available to general practitioners, patients and public health workers, and showed an adequate discrimination. Addition of blood markers from major biological pathways did not improve the performance of the model. Further replication in additional data sets may lead to further enhancement of the current model.
开发并验证一个预测老年人7年后发生运动功能障碍的模型。
前瞻性英国队列研究：用于模型开发的英国女性心脏与健康研究（BWHHS）以及用于验证的英国老龄化纵向研究（ELSA）。
社区居住的老年人。
采用向后逐步淘汰法选择预测因子后构建多变量逻辑回归模型。使用区分度和校准指标评估模型性能。对模型进行内部和外部验证。
在BWHHS中，1786名女性中有861名（48%）在7年后报告了运动功能障碍。年龄、关节炎病史和低体力活动水平是运动功能障碍最重要的预测因子。使用常规测量指标作为预测因子构建的模型具有良好的校准和区分度（C指数为0.73）。添加31种血液标志物并未提高预测性能。在ELSA中的外部验证显示区分度降低（C指数为0.65）且对残疾风险估计不足。可通过网络访问运动功能障碍计算器（http://www.sealedenvelope.com/trials/bwhhsmodel/）。
我们基于全科医生、患者和公共卫生工作者均可获取的常规测量指标，开发并对外验证了一个预测老年人发生运动功能障碍的模型，且该模型具有足够的区分度。添加主要生物学途径的血液标志物并未改善模型性能。在更多数据集上进一步重复验证可能会进一步优化当前模型。
