糖化血红蛋白联合稳态模型胰岛素抵抗指数对肥胖儿童糖尿病前期的诊断意义

Diagnostic value of glycosylated hemoglobin combined with homeostasis model assessment of insulin resistance in obese children with prediabetes

目的探讨糖化血红蛋白(HbA1c)和稳态模型胰岛素抵抗指数(HOMA-IR)对肥胖儿童糖尿病前期的诊断意义。方法收集2012年10月至2016年3月在天津医科大学总医院儿科门诊诊断为肥胖的儿童595例,均于空腹8~10h后进行口服葡萄糖耐量试验(OGTT)并测定HbA1c水平。按照世界卫生组织(WHO)标准,将肥胖儿童分为非糖尿病前期组(483例)和糖尿病前期组(112例),比较不同分组间HOMA-IR、HbA1c水平,分别绘制HbA1c和HOMA-IR筛查糖尿病前期的受试者工作特征(ROC)曲线,分析曲线下面积(AUC)及不同界点的诊断价值;利用Logistic回归建模,用保存的概率作为单独变量做ROC曲线,分析二者联合诊断糖尿病前期的AUC;利用Z检验比较各AUC差异有无统计学意义。结果糖尿病前期组肥胖儿童HbA1c及HOMA-IR水平[(5.65±0.36)%、11.60±8.86]均高于非糖尿病前期组[(5.47±0.32)%、6.49±4.61],2组比较差异均有统计学意义(均P<0.01)。HbA1c诊断糖尿病前期ROC曲线AUC为0.633,当诊断界点为5.585%时,灵敏度和特异度分别为0.584、0.601;HOMA-IR诊断糖尿病前期的ROC曲线AUC为0.758,当诊断界点为7.244时,灵敏度和特异度分别为0.779、0.669;2项指标联合时,AUC为0.764。与HbA1c相比,HOMA-IR单独或HOMA-IR联合HbA1c诊断糖尿病前期ROC曲线AUC差异均有统计学意义(均P<0.01)。HOMA-IR单独与HOMA-IR联合HbA1c诊断糖尿病前期ROC曲线AUC差异无统计学意义(P>0.05)。结论HOMA-IR单独或HOMA-IR联合HbA1c可作为诊断肥胖儿童糖尿病前期的良好指标。

Objective To study the diagnostic value of glycosylated hemoglobin(HbA1c)combined with homeostasis model assessment of insulin resistance(HOMA-IR)in obese children with prediabetes.Methods Five hundred and ninety-five obese children diagnosed at Outpatient Department of Pediatrics,Tianjin Medical University General Hospital were enrolled in the study from October 2012 to March 2016.Oral glucose tolerance test(OGTT)and HbA1c test were performed after fasting 8 to 10 hours for all the subjects.According to the World Health Organization(WHO)criteria,the obese children were divided into non-prediabetes group(483 cases)and prediabetes group(112 cases).The levels of HOMA-IR and HbA1c were compared between 2 groups.The receiver operating characteristic(ROC)curve was drawn for screening prediabetes,and the diagnosis value of area under curve(AUC)and different cutoff value were calculated.Logistic regression model was used to analyze the combined diagnosis of prediabetic AUC with preserved probability as a single variable and ROC curve.Z test was used to compare the statistical differences of each AUC.Results The levels of HbA1c and HOMA-IR of the prediabetes obese children group[(5.65±0.36)% and 11.60±8.86]were all higher than those of the non-prediabetes obese children group [(5.47±0.32)% and 6.49±4.61],and there were significant differences between 2 groups(all P<0.01).The AUC of HbA1c ROC for prediabetes was 0.633.When the cutoff was 5.585%,the sensitivity and specificity were 0.584 and 0.601,respectively.The AUC of HOMA-IR ROC for prediabetes was 0.758.When the cutoff was 7.244,the sensitivity and specificity were 0.779 and 0.669,respectively.When combined with HOMA-IR and HbA1c,the AUC was 0.764.Compared with HbA1c,there were significant differences in AUC of ROC curve between HOMA-IR alone or HOMA-IR combined with HbA1c in the diagnosis of prediabetes mellitus(all P<0.01).There was no significant difference in AUC of ROC curve between HOMA-IR alone and HOMA-IR combined with HbA1c in the diagnosis of prediabetes mellitus(P>0.05).Conclusions Only HOMA-IR or HOMA-IR combined with HbA1c may be the optimal indexes for diagnosing obese children with prediabetes.