·HbA1c测定和应用·

　　【摘 要】目的 探讨HbA1c检测在西藏高原藏族糖尿病及糖尿病前期的诊断价值。 方法 选取西藏拉萨地区无糖尿病史的藏族受试者321名，检测HbA1c及75g OGTT，以1999年WHO标准为”金标准”。绘制受试者工作特征曲线(ROC曲线)评估HbA1c诊断的敏感性及特异性。 结果 诊断藏族糖尿病最佳切点为HbA1c≥6.5%，敏感性93.9%，特异性95%，阳性似然比(+LR)18.7，阴性似然比(-LR)0.06，阳性预测值(+PV)86.5%，阴性预测值(-PV)97.8%;诊断藏族糖尿病前期最佳切点为HbA1c≥5.7%，敏感性54.3%，特异性74.7%，+LR 2.15,-LR 0.61，+PV 52.4%，-PV 76.1%. 结论 HbA1c≥6.5%可作为藏族糖尿病诊断切点，但不能充分识别西藏藏族糖尿病前期患者。

　　【关键词】 糖尿病;糖尿病前期;糖化血红蛋白;西藏高原;藏族

Significance of HbA1c for diagnosis of diabetes mellitus and prediabetes in Tibetan population LV Xue-mei, GAO Yun, WU Yun-hong, et al. Department of Endocrinology, Tibet Autonomous Region People’s Hospital, Lasa 850000, China

Corresponding author: TIAN Hao-ming, Email: hmtian999@yahoo.com.cn

　　【Abstract】 Objective To assess the significance of HbA1c as a screening tool for the diagnosis of diabetes mellitus and prediabetes in the Tibetan population in Tibet plateau. Methods A total of 321 Tibetan adults without history of diabetes were recruited from the physical examination center. Their HbAlc and other biochemical indices were observed for study. A 2-hour 75g oral glucose tolerance test (OGTT) was used to diagnose diabetes and prediabetes according to the criteria given by World Health Organization in 1999. Receiver operating characteristic curve (ROC) was plotted to determine the performance of HbA1c. Results An optimal cut-off point for DM diagnosis is HbA1c≥6.5%, the sensitivity was 93.9%, the specificity was 95%, the positive likelihood ratio (+LR) was 18.7, the negative likelihood ratio (-LR) was 0.06, the positive predictive value (+PV) was 86.5%, and the negative predictive value (-PV) was 97.8%. An optimal cut-off point for prediabetes diagnosis is HbA1c≥5.7%, the sensitivity was 54.3%, the specificity was 74.7%, the +LR was 2.15, the -LR was 0.61, the +PV 52.4%, and the -PV was 76.1%. Conclusion HbA1c≥6.5% can be used as a cut-off point for detecting undiagnosed diabetes in Tibetan adults, but it is not suitable for recognizing the prediabetes in Tibetan population.

　　【Key words】HbA1c; Diabetes mellitus; Prediabetes; Tibet plateau; Tibetan