Department of Pharmacy Practice, Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State University, Detroit, Michigan 48201-2417, USA.
J Clin Endocrinol Metab. 2011 Oct;96(10):E1680-3. doi: 10.1210/jc.2011-1148. Epub 2011 Aug 17.
Glycated hemoglobin (A1C) has been recommended by the American Diabetes Association for the diagnosis of diabetes and prediabetes. The diagnostic utility of A1C has not been evaluated in Arabs, a population at increased risk for developing diabetes.
Our objective was to examine the sensitivity and specificity of A1C for the diagnosis of diabetes and prediabetes in Arabs.
DESIGN & SETTING: In this cross-sectional study, glucose tolerance was classified by the American Diabetes Association diagnostic criteria specified for A1C, fasting plasma glucose, and 75-g oral glucose tolerance test.
A population-based representative sample of 482 randomly selected adult Arabs without known diabetes was studied.
Sensitivity, specificity, and area under the receiver operating characteristic curve of A1C diagnostic cutpoints for diabetes and prediabetes were calculated. κ Coefficients were used to test for agreement between A1C categorization and glucose-based diagnoses.
A1C testing correctly identified 5% of individuals diagnosed with diabetes by oral glucose tolerance test, 13% by fasting plasma glucose, and 41% by both criteria. A1C alone identified 14% of individuals diagnosed with impaired glucose tolerance, 9% with impaired fasting glucose, and 33% with both abnormalities. Sensitivity, specificity, and area under the receiver operating characteristic curve were 19% (16-23%), 100% (99-100%), and 77% (69-85%) for diabetes A1C cutpoint and 14% (11-17%), 91% (89-94%), and 57% (52-62%) for prediabetes A1C range. A1C cutpoint of 6.2% for diabetes and 5.1% for prediabetes yielded the highest accuracy but still missed 73% of those with diabetes and 31% with prediabetes. Agreement between A1C and diabetes (κ = 0.2835) or prediabetes (κ = 0.0530) was low.
A1C-based criteria yield a high proportion of false-negative tests for diabetes and prediabetes in Arabs.
Racial/ethnic differences in A1C performance for diagnosis and prediction of diabetes exist. This paper examines its utility against glucose measurements in an at-risk Arab population.
糖化血红蛋白（A1C）已被美国糖尿病协会推荐用于糖尿病和糖尿病前期的诊断。A1C 的诊断效用尚未在易患糖尿病的阿拉伯人群中进行评估。
我们的目的是检查 A1C 对阿拉伯人糖尿病和糖尿病前期的诊断的敏感性和特异性。
在这项横断面研究中，根据美国糖尿病协会针对 A1C、空腹血浆葡萄糖和 75g 口服葡萄糖耐量试验规定的标准，将葡萄糖耐量分为糖尿病和糖尿病前期。
研究了一个基于人群的、随机选择的、无已知糖尿病的 482 名成年阿拉伯人代表性样本。
计算 A1C 诊断切点的糖尿病和糖尿病前期的敏感性、特异性和受试者工作特征曲线下面积。κ 系数用于检验 A1C 分类与葡萄糖诊断之间的一致性。
A1C 检测正确识别了 5%的经口服葡萄糖耐量试验诊断为糖尿病的个体、13%的空腹血糖诊断为糖尿病的个体以及 41%的两项标准均诊断为糖尿病的个体。A1C 单独识别出 14%的糖耐量受损个体、9%的空腹血糖受损个体和 33%的两项异常个体。糖尿病 A1C 切点的敏感性、特异性和受试者工作特征曲线下面积分别为 19%（16%-23%）、100%（99%-100%）和 77%（69%-85%），而糖尿病前期 A1C 范围的敏感性、特异性和受试者工作特征曲线下面积分别为 14%（11%-17%）、91%（89%-94%）和 57%（52%-62%）。6.2%的糖尿病 A1C 切点和 5.1%的糖尿病前期 A1C 切点的准确性最高，但仍有 73%的糖尿病患者和 31%的糖尿病前期患者漏诊。A1C 与糖尿病（κ=0.2835）或糖尿病前期（κ=0.0530）的一致性较低。
A1C 标准对阿拉伯人群的糖尿病和糖尿病前期的检测结果有很高的假阴性率。
种族/民族之间存在 A1C 用于诊断和预测糖尿病的表现差异。本文研究了其在易患糖尿病的阿拉伯人群中与葡萄糖测量的相关性。
