单一测定空腹血糖在诊断糖尿病和糖耐量减低中的局限性

Limitation of fasting blood sugar levels in the diagnosis of diabetes mellitus and impaired glucose tolerance

分析了经７５ｇＯＧＴＴ确诊的７９７例糖尿病（ＤＭ）和８１８例糖耐量减低（ＩＧＴ）患者的空腹血糖（ＦＢＳ）水平，并与１２８９例正常人作了比较。结果显示：７９７例糖尿病患者中ＦＢＳ≥７．８ｍｍｏｌ／Ｌ者有５０９例（６３．８６％）。ＦＢＳ≥７．８ｍｍｏｌ／Ｌ诊断糖尿病的敏感性和特异性分别为６３．８６％和９９．３０％，ＦＢＳ≥６．１１ｍｍｏｌ／Ｌ则敏感性和特异性分别为９４．２３％和９１．５４％，假阳性率和假阴性率均不到１０％。８１８例ＩＧＴ患者的ＦＢＳ值正常者（＜６．１１ｍｍｏｌ／Ｌ）占７９．７１％，与正常人重叠较多。提示ＦＢＳ≥７．８ｍｍｏｌ／Ｌ对糖尿病的诊断不是一个敏感的指标，若ＦＢＳ≥６．１１ｍｍｏｌ／Ｌ者应作进一步检查。而用ＦＢＳ不能估价ＩＧＴ。

The fasting blood sugar(FBS) levels of 797 patients with diabetes mellitus(DM) and 818 patients with impaired glucose tolerance(IGT)diagnosed by 75g oral glucose tolerance test(OGTT) were analyzed and compared with that of 1289 normal subjects. The results showed that the FBS level was≥7.8mmol/L in 509 of the 797 diabetic patients(63.86%). The sensitivity and the specificity of FBS≥7.8mmol/L were 63.86% and 99.30%,respectively, in diagnosing DM. While both sensitivity and specificity of FBS over 6. 11mmol/L were 94.23% and 91. 54%, and both false negative and false positive rates were less than 10%. The FBS levels of most IGT were overlapped with that of normal subjects. It suggests that FBS level over 7. 8 mmol/L is not a sensitive indicator for the diagnosis of DM, all patients with FBS≥6. 11mmol/L should receive further examination and FBS level can not be used for diagnosis of IGT.