社区老年人认知衰弱风险预测模型的构建及验证

目的 构建并验证社区老年人认知衰弱风险预测模型。方法 2020年8月—2021年7月便利选取广州市某社区卫生服务中心526名体检老年人,分为建模集368名和验证集158名,采用一般状况调查表及认知衰弱评定工具收集资料。采用Logistic回归确定影响因素,应用R软件建立预测认知衰弱发生风险的列线图模型;采用加强Bootstrap法做模型内部验证,以验证集做外部验证,采用C统计量、校准曲线评价模型的预测性能。结果 模型变量包括工具性日常生活能力、自评健康状况、日间精神状态自评、慢性病数量、年龄、营养状况及体育锻炼,受试者操作特征曲线下面积为0.920（95%CI：0.892~0.947）,最佳临界值为0.401,灵敏度为79.7%,特异度为89.1%。内外部验证C统计量分别为0.910（95%CI：0.863~0.936）、0.850（95%CI：0.785~0.915）,校准曲线和Brier得分均显示拟合良好。结论 预测模型的区分度和校准度良好,可直观、简便地甄别社区认知衰弱高风险老年人,为早期筛查与干预提供参考。

Construction and validation of a prediction model for the risk of cognitive frailty among the elderly in a community

Objective To establish and validate a risk prediction model for cognitive frailty in community elderly. Methods 526 elderly people taking physical examinations were recruited in a community health service center in Guangzhou by convenience sampling from August 2020 to July 2021. They were divided into a modeling group （368 cases） and a validation group（158 cases）. Data were collected by a general information questionnaire and cognitive frailty assessment tools. Logistic regression was used to determine the influencing factors,and R software was used to establish a nomogram model for predicting the risk of cognitive frailty. Bootstrap method was used for internal validation of the model,and the validation group was used for external validation. C statistic and calibration curve were used to evaluate the prediction performance of the model. Results The model variables included IADL,self-rated health,daytime mental state,the number of chronic diseases,age,nutritional status and physical exercise. The AUROC of the model was 0.920（95%CI：0.892~0.947）,the best cutoff value was 0.401;the sensitivity was 79.7%;the specificity was 89.1%;The C statistics of internal and external validation were 0.910 （95%CI：0.863~0.936） and 0.850（95%CI：0.785~0.915）,respectively;calibration curve and Brier score showed good fit. Conclusion The prediction model has a good degree of discrimination and calibration,which can intuitively and easily screen the elderly at high risk of cognitive frailty in the community,and provide references for early screening and intervention.