糖化血红蛋白早期筛查糖尿病的截点探讨

Optimal cut-off point of glycosylated hemoglobin for early screen of diabetes mellitus

目的探讨HbA_1c早期筛查糖尿病的最佳截点。方法选取我院门诊和住院行OGTT和HbA_1c测定的对象613名。以1999年WHO诊断糖尿病的"金标准"2hPG≥11.1mmol/L分为糖尿病组(DM)和2hPG<11.1mmol/L非糖尿病组(NDM)。利用相关分析、受试者工作特征曲线(ROC)和约登指数确定HbA_1c筛查糖尿病的最佳截点。结果 DM组19.4%的患者HbA_1c<6.5%,NDM组80.6%的患者HbA_1c<6.25%。相关分析显示,HbA_1c与2hPG有相关性。HbA_1c与2hPG拟合回归方程为HbA_1c=3.031+0.290×2hPG。ROC曲线显示,最佳HbA_1c截点为6.25%。HbA_1c为6.25%时,敏感性为87.85%,特异性为80.67%。HbA_1c为6.25%时,具有最大的约登指数。结论 HbA_1c≥6.25%筛查糖尿病的有效率为94.97%,可使漏诊率降低至12.15%,适合作为早期筛查糖尿病的截点。

Objective To investigate the best glycosylated hemoglobin HbA_1c cut-off points on screening for diabetes. Methods A total of 613 cases accepted OGTT and HbA_1c measurement in our hospital were selected and analyzed.2hPG≥11.1 mmol/L was classified as diabetic group（DM）and2hPG11.1mmol/L as non-diabetic group（NDM）according to 1999 WHO diagnostic of diabetes.The optimal HbA_1c cut-off point for screening diabetes was identified using correlation analysis,ROC curve and youden index. Results 19.4% of patients in DM group had HbA_1c6.5%,and 80.6% of the patients in NDM group had HbA_1c6.25%.HbA_1c and 2hPG were significantly correlated.The regression equation was HbA_1c=3.031＋0.290×2hPG.ROC curve showed the best cut-off point of HbA_1c was6.25% with the sensitivity 87.85% and the specificity 80.67%.HbA_1c=6.25% had a maximum youden index. Conclusion The screening efficiency of HbA_1c≥ 6.25% for diabetes is 94.97% with the misdiagnosis rate decreased to 12.15%.