【作者】 肖海英；

【导师】 田慧； 裴育；

【作者基本信息】 中国人民解放军军医进修学院 ， 老年医学， 2011， 硕士

【摘要】 为探讨糖化血红蛋白(HbAlc)在糖尿病(DM)诊断中的应用价值,本研究分别对两组不同人群进行横断面流行病学调查,旨在评价糖化血红蛋白用于诊断糖尿病的价值,希望能为糖尿病的诊断提供可行性依据。研究第一部分：探讨HbAlc在两组不同人群中的分布特点及影响因素。结果提示：(1)中青年为主院校组(1064人)和老年社区组(1671人)的HbAlc均值分别为5.31±0.41%和5.79±0.71%,女性均高于男性(P<0.05)。(2)在总体人群中HbAlc随年龄增长而增长,仅在80～岁组这种趋势不显著。(3)在不同糖代谢水平下,HbAlc均值NDDM组>IGR组>NGT组,差异显著(P<0.05)研究第二部分：比较HbAlc在两组不同人群中糖代谢异常的诊断切点和临床意义。结果提示：(1)对应OGTT诊断结果计算HbAlc诊断的尤登指数,两组HbA1c诊断DM的切点分别是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%),诊断糖调节受损(IGR)的切点分别是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%)。合并计算诊断DM和IGR的切点与老年社区组相同。(2)按HbA1c5.9%和5.7%带入人群评估,HbA1c5.9%时,仅能诊断78.7%的DM,另包括39.6%的IGR和10.0%的正常糖耐量者(NGT)；HbA1c5.7%时涵盖了61.6%的IGR,另包括24.4%的NGT。按6.5%标准计算,可诊断符合OGTT糖尿病标准的38.5%,另包括4.1%的IGR和0.4%的NGT。(3)空腹血糖(FPG)≥7.0 mmol/L联合HbA1c≥5.9%用于诊断DM的敏感性为81.5%,优于单纯用HbAlc≥5.9%(敏感性为78.7%),但特异性低于ADA标准。综上所述HbAlc有性别差异,女性高于男性；且HbAlc水平随着年龄增长而升高；不同糖代谢水平对其亦有影响。老年人群HbA1c的平均水平高于中青年人群,HbAlc诊断DM和IGR的切点受评估人群年龄和HbA1c总水平的影响。本研究HbA1c 5.9%和5.7%带入人群作为DM和IGR诊断切点敏感性高但特异性差,不适合作为临床诊断指标。本研究HbA1c切点5.9%联合FPG>7.0 mmol/L诊断DM时,敏感性高于我国上海(≥6.3%)及ADA标准(≥6.5%),但特异性低于两者。HbAlc 6.5%为DM诊断标准虽敏感性差但特异性高,需结合FPG、RPG和OGTT作为临床诊断糖尿病标准之一。更多还原

【Abstract】 To study the utility of HbAlc in the diagnosis of diabetes mellitus,we assessed the validity of HbAlc for diagnosing diabetes by cross-sectional epidemiological survey in two diverse population groups,wishing to have new feasibility of diagnosing diabetes.The study consists of two parts. In part one, it was included that the distributional characteristics of glycohemoglobin Alc and its influencing factors in diverse population groups. The mean HbAlc of 1064 younger subjects in an academy and 1671 aged subjects in a community were 5.31±0.41% and 5.79±0.71%, respectively, HbAlc in femal was higher than in male (P<0.05) HbAlc increases along with the age in the general population, but this trend is not significant after 80～years old. The mean value of HbAlc in NDDM group was higher than IGR and NGT.In part two, to compare the difference of cutpoint and clinical significance of glycohemoglobin (HbAlc) for the diagnosis of abnormal glucose metabolism in diverse population groups.We found that the cutpoints of HbAlc 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 that for diagnosis of IGR were 5.6%(specificity 82.8%, sensitivity 55.8%) and 5.7%(specificity 60.9%, sensitivity 64.3%), respectively. At HbAlc levels of>5.7%,≥5.9%and≥6.5%, diabetes diagnosed by current OGTT criteria occurred in 87.8%,78.7%and 38.5%, IGR diagnosed occurred in 61.6%,39.6% and 4.1%, and normal glucose tolerance (NGT) diagnosed occurred in 24.4%,10.0% and 0.4%. The screening model using FPG7.0 mmol/L and/or HbAlc>5.9% had more sensitivity(81.5%) than HbAlc(78.7%), but the specificity of 5.9% was lower than the standard of ADA for diagnosing diabetes.On the whole, HbAlc in femal was higher than in male; and HbAlc increases along with the age. HbAlc has been influenced on different glucose metabolism in diverse population groups. The mean value of HbAlc in aged population was higher than younger population, with a corresponding difference of cutpoint for diagnosis of diabetes and IGR. HbAlc 6.5% but not 5.9% should be better for clinical diagnosed as diabetes criteria because of relatively higher specificity. The combined use of glycated hemoglobin Alc(HbAlc>5.9%) and fasting plasma glucose(FPG>7.0 mmol/L) in our study to detect undiabnosed diabetes mellitus has more sensitivity than the criteria of shanghai and ADA,but specificity was lower.However, as one of diagnosis with diabetes, HbAlc 6.5% may be combined with fasting plasma glucose, random plasma glucose and OGTT.更多还原