南昌社区中老年人群糖尿病流行病学调查中HbA1C对诊断2型糖尿病的价值

选择南昌1 415例中老年人作为研究对象,分为正常糖耐量组、糖调节受损组及糖尿病组.结果 显示,HbA1C与空腹血糖(FPG)及餐后2 h血糖呈显著相关,HbA1C 6.3%诊断糖尿病的敏感度为85.19%,特异度为99.45%,HbA1C 6.5%诊断糖尿病的敏感度为75.56%,特异度为99.61%.在本研究的人群中,HbA1C 6.3%诊断糖尿病较HbA1C 6.5%及FPG 7.0 mmol/L具有更高的敏感性.

Abstract：

A total of1415 elderly individuals in Nanchang were included in the study and were divided into normal glucose tolerance group, impaired glucose regulation group, and diabetes mellitus group.The results showed that HbA1C was significantly correlated with fasting plasma glucose (FPG) and 2 h postprandial plasma glucose.When HbA1C 6.3% was applied as the cut point of diabetes, the sensitivity was 85.19% and the specifity was 99.45%.When HbA1C 6.5% was applied, the sensitivity was 75.56% and specifity was 99.61%.It seems that HbA1C 6.3% had higher specifity and sensitivity for diagnosing diabetes than HbA1C 6.5% and FPG 7.0mmol/L in studied population.     

糖化血红蛋白诊断糖尿病切点的横断面研究

目的 比较HbA1C在两组不同年龄人群中糖代谢异常的诊断切点和临床意义.方法 与口服葡萄糖耐量试验(OGTT)比较,在两个经糖尿病筛查(横断面资料)、不同年龄分布的人群中对HbA1C诊断2型糖尿病和糖调节受损(IGR)的切点进行分析,探讨其临床意义.结果 中青年为主的院校组(1 064人)和老年社区组(1 671人)的HbA1C均值分别为5.31%±0.41%和5.79%±0.71%.对应OGTT诊断的结果计算HbA1C诊断的尤登指数,两组HbA1C诊断糖尿病的切点分别为5.7%(特异性86.7%,敏感性66.7%)和5.9%(特异性73.8%,敏感性80.1%),诊断IGR的切点分别为5.6%(特异性82.8%,敏感性55.8%)和5.7%(特异性60.9%,敏感性64.3%).在总人群中以HbA1C 5.7%、5.9%和6.5%为切点,诊断为糖尿病的患者分别为87.8%、78.7%和38.5%,IGR为61.6%、39.6%和4.1%,正常糖耐量者24.4%、10.0%和0.4%.结论 HbA1C诊断糖尿病和IGR的切点受评估人群年龄和HbA1C水平的影响.HbA1C6.5%虽敏感性差但特异性高,需结合空腹血糖、随机血糖和OGTF作为临床诊断糖尿病标准之一.

Abstract：

Objective To compare the difference of cutpoint and clinical significance of HbA1C for the diagnosis of abnormal glucose metabolism in two population groups with different ages.Methods According to oral glucose tolerance test(OGTT),the cutpoint and clinical significance of HbA1C for the diagnosis of type 2 diabetes and impaired glucose regulation(IGR)were investigated in the two population groups.Results The mean HbA1C of 1 064 young subjects in an academy and 1 671 aged subjects in a community were 5.31% ±0.41% and 5.79% ±0.71%,respectively.The cutpoints of HbA1C for diagnosis of diabetes were 5.7%(specificity 86.7%,sensitivity 66.7%)and 5.9%(specificity 73.8%,sensitivity 80.1%)in the two population groups,and 5.6% for diagnosis of IGR (specificity 82.8%,sensitivity 55.8%)and 5.7%(specificity 60.9%,sensitivity 64.3%),respectively.87.8%,78.7%,and 38.5% were diagnosed diabetes by current OGTT criteria at HbA1C levels of ≥5.7%,≥5.9%,and≥6.5%,IGR being 61.6%,39.6%,and 4.1%,and normal glucose tolerance being 24.4%,10.0%,and 0.4%.Conclusion The cutpoints of HbA1C for diagnosis of diabetes and IGR are different in populations with different ages and HbA1C levels.As one of diagnostic criteria for diabetes,HbA1C 6.5% with relatively higher specificity and lower sensitivity must be combined with fasting blood glucose,random blood glucose,and OGTT.     

青少年人群诊断糖尿病前期不宜采用糖化血红蛋白标准

目的 探索2010年美国糖尿病协会(ADA)推荐的糖尿病前期HbA1C诊断标准在中国青少年人群中的适用性.方法 随机抽取辽阳市初中和高中学生933人(13～16岁,女性46.5%),测定HbA1C和空腹血糖,对HbA1C5.7%～6.4%的部分受试者进行口服葡萄糖耐量试验(OGTT),以受试者工作特性(ROC)曲线评价HbA1C对糖尿病前期的诊断价值.结果 符合ADA 2010年推荐的糖尿病前期诊断标准者213人,其中同时符合HbA1C和空腹血糖标准者仅占4.7%.HbA1C诊断空腹血糖升高的ROC曲线下面积为0.50(P=0.97).由HbA1C标准诊断糖尿病前期并行OGTF的68人中18人确定为糖耐量受损或空腹血糖受损,HbA1C诊断糖尿病前期的ROC曲线下面积为0.53(P=0.69).结论 在中国青少年人群中HbA1C不宜作为糖尿病前期的诊断方法.

Abstract：

Objective To evaluate the performance of HbA1C in diagnosis of pre-diabetes in Chinese adolescents.Methods A total of 933 students(aged 13-16 year,46.5% female)without known history of diabetes were selected from junior and senior middle schools in Liaoyang city.HbA1C and fasting plasma glucose(FPG)levels were determined in all participants.Pre-diabetes was diagnosed as according to 2010 American Diabetes Association (ADA)criteria[HbA1C 5.7%-6.4%,FPG(5.6-6.9)mmol/L].The individuals with HbA1C ≥5.7% underwent oral glucose tolerance test(OGTT)and were classified into impaired glucose tolerance(IGT)and impaired fasting glucose(IFG)according to 1999 World Health Organization(WHO)criteria.The performance of HbA1C in diagnosing pre-diabetes by the new criteria was evaluated by the traditional OGTT results based on receiver operating characteristic(ROC)curves.Results Among all participants,213(22.8%)individuals were diagnosed as prediabetic subjects.72.3% of individuals with pre-diabetes were identified by HbA1C alone,23.0% by FPG alone,and only 4.7% by both tests simultaneously.The ROC curve for HbA1C to identify impaired fasting glucose diagnosed by new criteria had an area under the curve(AUC)of 0.50 without statistical significance(P = 0.97).Of the 164 participants with HbA1C 5.7% -6.4%,68 individuals received OGTT,among which 18 subjects were diagnosed as IGT(n= 14)or IFG(n = 4).The ROC curve for HbA1C to identify pre-diabetes diagnosed by OGTT had an AUC of 0.53,without statistical significance(P = 0.69).Conclusion In Chinese adolescents,HbA1C is not suitable for diagnosis or screening of pre-diabetes.     

糖尿病高风险人群糖化血红蛋白与微血管并发症的关系

目的 探讨在广州地区的糖尿病高风险人群中HbA1C与糖尿病微血管并发症之间的关系,并评价其对糖尿病的诊断价值.方法 对208例糖尿病高风险患者进行HbA1C、血糖、眼底彩色照相及微量白蛋白尿测定.以受试者工作特征(ROC)曲线比较HbA1C、空腹血糖(FPG)、餐后2 h血糖(2hPG)的诊断效果.结果 高风险人群中糖尿病视网膜病变患病率为14.9%,微量白蛋白尿患病率为12%.HbA1C、FPG和2hPG分别为5.8%、7.0 mmol/L和10.9 mmol/L时视网膜病变的发病率显著增加.HbA1C、FPG和2hPG分别为5.8%、6.4mmol/L和10.7mmol/L时微量白蛋白尿发病率明显增加.结论 HbA1C为5.8%时糖尿病高风险人群微血管并发症患病率显著增加,HbA1C和2hPG判断微血管并发症的效果无明显差异,FPG相对偏低.

Abstract：

Objective To explore the association of HbA1C with microvascular complications,and to evaluate the diagnostic value of HbA1C in diabetes mellitus in high-risk populations of Guangzhou.Methods HbA1C,blood glucose,fundus photography,and microalbuminuria were detected in 208 permanent residents with high-risk factors of diabetes.The receiver operating characteristiC(ROC)curves were used to estimate the area of HbA1C,fasting plasma glucose(FPG),postprandial 2 h plasma glucose(2hPG)under the curve for discriminating microvascular complications.Results There were 14.9% adults suffering from diabetic retinopathy and 12% microalbuminuria in high risk populations of diabetes.The optimal cutoff points of HbA1C,FPG,and 2hPG in detecting retinopathy were 5.8%,7.0 mmol/L,and 10.9 mmol/L respectively.The thresholds for increasing prevalence of microalbuminuria were5.8% for HbA1C,6.4 mmol/L for FPG,and 10.7 mmol/L for 2hPG.Conclusions The prevalence of diabetic microvascular complications increases dramatically at the concentration of HbA1C 5.8%.As a diagnostic value for microvascular complications,there is no significant difference between HbA1C and 2hPG.     

不同糖代谢状态人群糖化血清白蛋白与HbA1c的相关性分析

ObjeclJve To definine the corresponding value to glycated albumin(GA)for a specific target of HbAlc,and to elvaluate the relationship between GA and HbA1c.Methods From Oct.2006 TO Apr.2009, 2 532 subjects were enrolled who accepted oral glucose tolerance test(OGtt)in out-patient department,including 898 with normal glucose regulation,695 with impaired glucose regulation,and 939 with newly-diagnosed diabetes.GA was measured with liquid enzymatic method.HbA1c was measured with high performance liquid chromatography method.The plasma glucose was measured at fasting,0.5 h,1 h,2 h,and 3h after glucose load.The correlation among GA,HbA1c and the other parameters monitored was analyzed.Results (1)The levels of HbA1c and GA in 2 532 subjects were(6.3±1.1)% and(17.9±4.5)%.The ratio of GA/HbA1c was 2.85±0.51.(2)HbAlc and GA were positively correlated with fasting,0.5 h,1 h,2 h and 3 h plasma glucose(r was in 0.567-0.776,atl P<0.01).(3)GA was significantly correlated with HbA1c(r=0.701,P<0.01).Linear regression analysis,using GA and HbA1c summarized by patient(n=2 532),produced a relationship of GA=2.871×HbA1c-0.112.The change in GA per increase of 1% HbA1c was 2.87%.When HbA1c level was 6.5%,the expected value of GA was 18.5%.The sensitivity,specificity,positive predictive value,negative predictive value,and accuracy with GA≤18.5% to predict HbA1c≤6.5% were 82.32%,72.49%,86.48%.65.73%,and 79.19%,respectively.When HbA1c level was 7.0%,the expected value of GA was 20.O%.When HbA1c level was 7.5%.the expected value of GA was 21.4%.Conclusions We initially establish the corresponding value to GA for a specific target of HbA1c and provide the basis for clinical application.     

不同糖代谢状态人群糖化血清白蛋白与HbA1c的相关性分析

ObjeclJve To definine the corresponding value to glycated albumin(GA)for a specific target of HbAlc,and to elvaluate the relationship between GA and HbA1c.Methods From Oct.2006 TO Apr.2009, 2 532 subjects were enrolled who accepted oral glucose tolerance test(OGtt)in out-patient department,including 898 with normal glucose regulation,695 with impaired glucose regulation,and 939 with newly-diagnosed diabetes.GA was measured with liquid enzymatic method.HbA1c was measured with high performance liquid chromatography method.The plasma glucose was measured at fasting,0.5 h,1 h,2 h,and 3h after glucose load.The correlation among GA,HbA1c and the other parameters monitored was analyzed.Results (1)The levels of HbA1c and GA in 2 532 subjects were(6.3±1.1)% and(17.9±4.5)%.The ratio of GA/HbA1c was 2.85±0.51.(2)HbAlc and GA were positively correlated with fasting,0.5 h,1 h,2 h and 3 h plasma glucose(r was in 0.567-0.776,atl P<0.01).(3)GA was significantly correlated with HbA1c(r=0.701,P<0.01).Linear regression analysis,using GA and HbA1c summarized by patient(n=2 532),produced a relationship of GA=2.871×HbA1c-0.112.The change in GA per increase of 1% HbA1c was 2.87%.When HbA1c level was 6.5%,the expected value of GA was 18.5%.The sensitivity,specificity,positive predictive value,negative predictive value,and accuracy with GA≤18.5% to predict HbA1c≤6.5% were 82.32%,72.49%,86.48%.65.73%,and 79.19%,respectively.When HbA1c level was 7.0%,the expected value of GA was 20.O%.When HbA1c level was 7.5%.the expected value of GA was 21.4%.Conclusions We initially establish the corresponding value to GA for a specific target of HbA1c and provide the basis for clinical application.     

Post-load hyperglycaemia and diagnostic criteria for diabetes

The evolution of 2 h post-load glucose tolerance test for diagnosis of diabetes and its clinical implication was reviewed and discussed. Post-load hyperglycemia is a risk factor for both microand macro-vascular diseases. According to its relationship with retinopathy,the current cut-off values for diabetes was defined since 1979. Recently,strong evidence has shown that post-load hyperglycemia is also an important risk factor for cardiovascular disease （ CVD）, the relation is linear and no a threshold was found. There are large discrepancies between fasting and 2 h glucose criteria in the classification of diabetes and impaired glucose tolerance （IGT）/impaired fasting glucose （IFG）. For early diagnosis and intervention administrating a 2 h OGTT to suspect individuals is necessary.     

不同血糖状态人群血浆内脂素水平及其相关因素

Fasting plasma visfatin was determined in subjects with various types of glucose tolerance. Visfatin level was (17.64±1.37)μg/L in subjects with normal glucose tolerance,and rose to (27.42±1.34) μg/L(P<0.05) in those with impaired glucose tolerance or impaired fasting glucose, and to(26.55 ± 1.64) μg/L(P< 0.05)in diabetic patients. No difference was found between obese and non-obese subjects. Positive correlation existed between visfatin and HbA1c(r=0. 317,P<0.01). Multiple linear step-wise regression showed that HbA1c and fasting plasma glucose had independent relation with the visfatin level. The result suggests that plasma visfatin may be related to glueometabolism and may play a role in the development of type 2 diabetes.     

不同血糖状态人群血浆内脂素水平及其相关因素

Fasting plasma visfatin was determined in subjects with various types of glucose tolerance. Visfatin level was (17.64±1.37)μg/L in subjects with normal glucose tolerance,and rose to (27.42±1.34) μg/L(P<0.05) in those with impaired glucose tolerance or impaired fasting glucose, and to(26.55 ± 1.64) μg/L(P< 0.05)in diabetic patients. No difference was found between obese and non-obese subjects. Positive correlation existed between visfatin and HbA1c(r=0. 317,P<0.01). Multiple linear step-wise regression showed that HbA1c and fasting plasma glucose had independent relation with the visfatin level. The result suggests that plasma visfatin may be related to glueometabolism and may play a role in the development of type 2 diabetes.     

不同血糖状态人群血浆内脂素水平及其相关因素

Fasting plasma visfatin was determined in subjects with various types of glucose tolerance. Visfatin level was (17.64±1.37)μg/L in subjects with normal glucose tolerance,and rose to (27.42±1.34) μg/L(P<0.05) in those with impaired glucose tolerance or impaired fasting glucose, and to(26.55 ± 1.64) μg/L(P< 0.05)in diabetic patients. No difference was found between obese and non-obese subjects. Positive correlation existed between visfatin and HbA1c(r=0. 317,P<0.01). Multiple linear step-wise regression showed that HbA1c and fasting plasma glucose had independent relation with the visfatin level. The result suggests that plasma visfatin may be related to glueometabolism and may play a role in the development of type 2 diabetes.     

糖化血红蛋白用于筛查糖尿病的意义

目的比较并评价空腹血糖（FPG）和糖化血红蛋白（HbA1c）在筛查DM中的应用价值。方法上海地区研究对象2298名,为明确DM诊断而就诊者和DM高危人群接受DM筛查者,男956名,女1342名,年龄52±13岁,行OGTT并测定HbA1C;以其工作特征曲线（ROC）评价FPG和HbA。C在筛查DM中的敏感性和特异性。结果（1）按照1999年WHO的DM诊断标准,本研究人群糖耐量正常（NGT）、空腹血糖受损（IFG）、糖耐量受损（IGT）、IGT合并IFG和DM者分别为830、110、380、183、795例。其中DM患病率为34．6％。（2）依据ROC判断,与DM状态相关的FPG最佳临界点为6．1mmol／L,敏感性和特异性均为81．5％,曲线下面积为0．899（95％CI0．885～0．914）,阳性似然比4．18,阴性似然比0．23;与DM状态相关的HbA1c最佳临界点为6．1％,敏感性和特异性均为81．0％,曲线下面积为0．890（95％CI0．876-0．904）,阳性似然比4．26,阴性似然比0．23;如应用FPG≥6．1mmol／L或HbA1c≥6．1％筛查DM,敏感性和特异性分别为96．5％和65．2％,阳性似然比2．77,阴性似然比0．05。结论FPG和HbA1C在筛查DM中具有相似的价值,二者均有相似的特异性和敏感性以及阳性似然比和阴性似然比。为了最大限度的筛查出DM患者,建议对于6．1mmol／L≤FPG〈7．0mmol／L或HbA1c≥6．1％的患者行OGTT检查以明确有无DM。     

Combined use of fasting plasma glucose and glycated hemoglobin A1c in the screening of diabetes and impaired glucose tolerance

The aim of this study is to assess the validity of combined use of fasting plasma glucose (FPG) and glycated hemoglobin A1c (HbA1c) as screening tests for diabetes and impaired glucose tolerance (IGT) in high-risk subjects. A total of 2,298 subjects were included. All subjects underwent a 75-g oral glucose tolerance test (OGTT) and HbA1c measurement. Receiver operating characteristic curve (ROC curve) analysis was used to examine the sensitivity and specificity of FPG and HbA1c for detecting diabetes and IGT, which was defined according to the 1999 World Health Organization (WHO) criteria. (1) Based on the ROC curve, the optimal cut point of FPG related to diabetes diagnosed by OGTT was 6.1 mmol/l that was associated with a sensitivity and specificity of 81.5 and 81.0%, respectively; The optimal cut point of HbA1c related to diabetes diagnosed by OGTT was 6.1%, which was associated with a sensitivity and specificity of 81.0 and 81.0%, respectively; The screening model using FPG ≥ 6.1 mmol/l or HbA1c ≥ 6.1% had sensitivity of 96.5% for detecting undiagnosed diabetes; the screening model using FPG ≥ 6.1 mmol/l and HbA1c ≥ 6.1% had specificity of 96.3% for detecting undiagnosed diabetes. (2) Based on the ROC curve, the optimal cut point of FPG related to IGT diagnosed by OGTT was 5.6 mmol/l that was associated with a sensitivity and specificity of 64.1 and 65.4%, respectively; The optimal cut point of HbA1c related to IGT diagnosed by OGTT was 5.6%, which was associated with a sensitivity and specificity of 66.2 and 51.0%, respectively; The screening model using FPG ≥ 5.6 mmol/l or HbA1c ≥ 5.6% had sensitivity of 87.9% for detecting undiagnosed IGT; The screening model using FPG ≥ 5.6 mmol/l and HbA1c ≥ 5.6% had specificity of 82.4% for detecting undiagnosed IGT. Compared with FPG or HbA1c alone, the simultaneous measurement of FPG and HbA1c (FPG and/or HbA1C) might be a more sensitive and specific screening tool for identifying high-risk individuals with diabetes and IGT at an early stage.     

HbA1C和空腹血糖在糖尿病筛查中的应用价值

目的探索HbA1c及FPG筛查糖尿病（DM）的应用价值。方法南京地区参加体检的未诊断糖尿病1330例,测定FPG和HbA1c,予标准化早餐后测定餐后2小时血糖（2hPG）,用受试者工作特征曲线（ROC）评价FPG和HbA1C筛查糖尿病的效果。结果按1999年WHO的糖尿病诊断标准,本研究人群DM患病率为6．8％。采用ROC曲线判断,与DM状态相关的FPG临界点为6．1mmol／L,敏感性和特异性分别为81．3％和96．3％;HbA1c临界点为6．1％,敏感性和特异性分别为83,5％和88．8％。当采用FPG≥6．1mmol／L或HhA1c≥6．1％作为标准时,敏感性达到92．3％,同时有较好的特异性81．2％。结论单独使用FPG较HbA1c在筛查DM中具有稍高的价值,为了最大限度的筛查DM患者,建议对6．1mmol／L≤FPG≤7．0mmol／L或HbA1c≥6．1％的患者行OGTT以明确有无糖尿病。     

糖化血红蛋白切点和糖调节异常的相关性研究

目的探讨HbAlc的可能切点和糖调节异常的相关性。方法江苏地区既往无糖尿病、具有糖尿病高危因素而接受筛查的受检者397名,男217名,女180名,行口服葡萄糖耐量试验（OGTT）,同时测定HbAlc。采用受试者工作特征曲线（ROC曲线）进行判断,以OGTT诊断糖尿病时HbAlc对应的可能切点。结果根据2004年美国糖尿病学会（ADA）的糖尿病诊断标准,本研究人群糖尿病233例,空腹血糖受损（IFG）24例,糖耐量受损（IGT）40例,糖调节异常（IGR）62例,糖耐量正常（NGT）38例。ROC曲线提示,以HbAlc作为诊断糖尿病的切点为6．1％（敏感性80．25％,特异性71．30％）;以FBG≥6．3mmol/L或HbAlc≥6．1％作为诊断糖尿病的敏感性和特异性分别为91．85％和59．76％;以FBG≥6．3mmol/L且HbAlc≥6．1％诊断糖尿病的敏感性和特异性分别为60．52％和89．63％。结论FBG≥6．3mmol/L或HbAlc≥6．1％者仍应行OGTF以明确是否患有糖尿病。     

2型糖尿病HbA1c筛查值和诊断值的探讨

目的评估HbA1c在筛查和诊断T2DM中的有效性。方法对497例（男361例,女136例）体检FPG≥5．6mmol／L者行OGTT并测定HbA1c、血脂、尿酸、血压等代谢指标。结果（1）应用受试者工作特性曲线（ROC）进行统计分析,与OGTT诊断DM的相关HbA1c最佳切点为6．3％,敏感性和特异性分另U是79．60％和82．20％,曲线下面积（AUC）为0．873（95％CI0．831-0．916）,HbA1c为6．5％时的敏感性和特异性分别是62．70％和93．50％。（2）按2010年ADA的DM诊断标准,分别按HbA1c≥6．5％或OGTT标准诊断DM,无论是否去除两组重叠部分,以HbA1c≥6．5％标准诊断的DM组的HbA1c水平显著高于以OGTT标准诊断的DM组,而FPG、2hPG均显著低于以OGTT标准诊断的DM组,其余代谢指标如血压、血脂、尿酸等均无统计学差异。结论当HbA1c≥6．3％时应进一步行OGTT以明确有无DM,而HbA1c≥6．5％具有较好的特异性可用于诊断DM,与ADA的推荐一致。     

从血糖稳态看空腹血糖受损下限切点下调

目的寻找预测2型糖尿病（T2DM）和糖耐量受损（IGT）发生的最佳空腹血糖受损（IFG）下限切点及下调的合理性。方法根据OGTT结果对北京城区2589例年龄≥20岁、既往无糖尿病史的自然人群的FPG进行ROC分析,绘制ROC曲线,并进行糖脂代谢分析。结果预测T2DM和IGT发生的最佳IFG下限切点ROC曲线下面积分别为0．949、0．692。用FPG来预测T2DM和IGT,其灵敏度及特异度均较好的点分别为5．6mmol／L和5．2mmol／L。与FPG〈5．6mmol／L组比较,FPG5．6～6．1mmol／L组胰岛素抵抗更加明显,胰岛素分泌下降,TG升高和HDL—C降低。结论将5．6mmol／L作为IFG的下限值适用于北京城区中国人群。     

Fasting plasma glucose and glycated haemoglobin in the screening of diabetes and impaired glucose tolerance

Abstract. The use of fasting plasma glucose (FPG) only has been proposed for the screening and diagnosis of diabetes, but its sensitivity has been reported to be unsatisfactory. The use of HbA_1C, alone or combined with FPG, has been suggested for the screening of diabetes and impaired glucose tolerance (IGT). In a sample of 1215 adult subjects without previously known diabetes, we assessed the sensitivity and specificity of FPG and HbA_1C in diagnosing diabetes and IGT, determined by oral glucose tolerance test (OGTT). All lean diabetic patients, and 85% of overweight and obese diabetic individuals, had FPG 7 mmol/l. FPG >6.1 mmol/l had a sensitivity of 98.8% and a specificity of 32.9%; HbA_1C had a lower specificity and sensitivity for the screening of diabetes. A screening strategy for diabetes based on FPG, with OGTT in all overweight subjects with FPG >6.1 mmol/l, is suggested. Neither FPG nor HbA_1C is effective in the screening of IGT; although combined FPG and HbA_1C could be useful for case finding, screening for IGT with OGTT is advisable in all subjects at high risk.     

糖化血红蛋白在糖尿病及空腹血糖受损诊断中的价值

目的 探讨HbA1c在糖尿病及IFG诊断中的意义。方法选取526名未诊断糖尿病及IFG者同时检测HbA1C和FPG。按ADA诊断标准（FI）G≥7．0mmol／L）、IFG标准（5．6mmol／L≤FPG46．9mmol／L）和2010年ADA新标准（HbA1c≥6．5％及5．7％≤HbA1c≤6．4％）将研究对象分组。以FPG为“金标准”,统计HbA1C诊断糖尿糖及IFG的敏感性（s）、特异性（Sp）、阳性似然比（＋ut）、阴性似然比（-LR）。结果HbA1c≥6．5％诊断糖尿病的s为96％,Sp为95％,＋LR为19．2,-LR为0．042;5．7N≤HbA1c≤6．4％诊断IFG的S为26％,sp为94％,＋LR为4．3,-LR为0．79。结论HbA1C诊断糖尿病有较高的诊断敏感性和特异性,在诊断IFG时特异性较高,而敏感性较低。     

Strategies to detect abnormal glucose metabolism in people at high risk of cardiovascular disease from the ORIGIN (Outcome Reduction with Initial Glargine Intervention) trial population

Background: To investigate whether the combination of HbA1c and fasting plasma glucose (FPG) can be used for the diagnosis of diabetes and impaired glucose tolerance (IGT) in people at high risk of cardiovascular disease (CVD). Methods: A cross‐sectional study was performed on 2907 people at high risk of cardiovascular events but without a previous diagnosis of diabetes. Optimal cut‐off points and the diagnostic potential of FPG, HbA1c, and their combination were determined. Results: The sensitivity of the usually applied FPG cut‐off point of 7.0 mmol/L to diagnose diabetes mellitus was low (59.0%). Receiver operating characteristic (ROC) curve analysis indicated that the optimal cut‐off points for the diagnosis of diabetes using FPG and HbA1c were 6.4 mmol/L (sensitivity 75.7%; specificity 77.5%; likelihood ratio 3.37) and 5.9% (41 mmol/mol; sensitivity 68.7%; specificity 67.1%; likelihood ratio 2.09), respectively. To diagnose IGT, the optimal cut‐off points for FPG and HbA1c were 6.1 mmol/L (sensitivity 57.1%; specificity 57.9%) and 5.7% (39 mmol/mol; sensitivity 63.8%; specificity 60.3%), respectively. For diabetes, combining cut‐off points for FPG and HbA1c identified four categories with likelihood ratios ranging from 5.59 to 0.21, and post‐test probabilities between 69.3% and 7.8%. For IGT, likelihood ratios varied between 2.05 and 0.56, whereas post‐test probabilities ranged from 84.0% to 58.8%. Conclusions: Using FPG alone results in the underdiagnosis of glucometabolic abnormalities in people at high risk of CVD. Using an algorithm with both HbA1c and FPG improves the detection of diabetes, but not IGT, and could be easily implemented in patient care.