江西儿童青少年体质指数预测高血压曲线分析

目的 分析体质指数(BMI)预测高血压受试者工作特征(ROC)曲线下面积,探讨中国学龄儿童青少年超重、肥胖筛查体重指数分类标准预测江西县区儿童青少年高血压的灵敏度和特异度。方法 于2013年采用随机整群抽样方法对江西省县区5260名11~17岁儿童青少年进行身高、体重、血压的测量,分析儿童青少年BMI与血压的关系,绘制ROC曲线,观察曲线下面积,计算超重、肥胖界值点的灵敏度和特异度。结果 BMI预测高血压ROC曲线下面积男、女生(0.590、0.563)均>0.5(P=0.000);男、女生超重点和肥胖点的灵敏度(0.206、0.081;0.078、0.018)均低于ROC曲线上的理想界值点(0.551、0.433);而男、女生超重点及肥胖点的特异度(0.903、0.951;0.977、0.994)均高于ROC曲线上的理想界值点(0.592、0.668)。结论 中国学龄儿童青少年超重、肥胖筛查体重指数分类标准预测江西县区儿童青少年高血压的特异度较高。

Application of body mass index in prediction of hypertension among children and adolescents in Jiangxi province: a receiver operating characteristic curve analysis

Objective To analyze the area under the receiver operating characteristic(ROC) curve(AUC) for body mass index(BMI) to predict hypertension and to assess the sensitivity and specificity of BMI classification criteria for overweight and obesity screening when applied in prediction of hypertension among Chinese children and adolescents.Methods A total of 5260 students aged 11-17 years were selected with random cluster sampling in Jiangxi province;height, weight and blood pressure were measured and the relationship between BMI and blood pressure were analyzed among the students.The ROC curve for BMI in prediction of hypertension was plotted and the AUC, the sensitivity and specificity of overweight and obesity cut-off points were calculated.Results The AUC for BMI in prediction of hypertension among the boys and girls were 0.590 and 0.563 and both were greater than 0.5(P=0.000).The sensitivity of overweight and obesity cut-off point for the boys were 0.206 and 0.078 and those for the girls were 0.081 and 0.018, and the two sets were both lower than the sensitivity of the optimal cut-off points on the ROC curve(0.551 and 0.433);but the specificity of the overweight and obesity cut-off point for the boys were 0.903 and 0.977 and those for the girls were 0.951 and 0.944, and the two sets were both higher than the specificity of optimal cut-off points on the ROC curve(0.592 and 0.668).Conclusion The specificity of BMI classification criteria for overweight and obesity screening is high when the BMI criteria are applied for predicting hypertension among children and adolescents in Jiangxi province.