糖化血红蛋白联合空腹血糖检测在甲状腺功能亢进伴糖代谢异常患者中的诊断价值

Value of hemoglobin Alc combined with fasting blood glucose in diagnosing abnormal glucose metabolism in patients with hyperthyroidism

目的探讨甲状腺功能亢进(下称"甲亢")患者采用HbA_1c联合FPG筛查糖尿病及糖尿病前期的敏感性和特异性并确定相应的最佳切点。方法选取2013~2016年于我院内分泌科住院的甲亢患者508例,行OGTT,检测HbA_1c、FPG及2hPG,测定身高和体重,计算BMI,采用受试者工作特征曲线(ROC)获得HbA_1c诊断和筛查糖尿病及糖尿病前期的相关切点及阳性似然比(+LR)、阴性似然比(-LR)。结果糖耐量正常组(NGT)、糖尿病前期组(IGR)、糖尿病(DM)组HbA_1c水平依次升高[(5.3±0.2)%vs(5.5±0.3)%vs(6.0±0.4)%,P<0.001]。依据ROC曲线判定,本组人群中HbA_1c筛查糖尿病前期的最佳临界点为5.4%,敏感性为55.9%,特异性为64.39%。HbA_1c诊断糖尿病的最佳临界点为5.5%,敏感性为79.71%,特异性为73.16%。结论 HbA_1c可准确反映甲亢患者不同阶段的糖代谢异常状态,在甲亢患者中诊断和筛查糖尿病前期及糖尿病的ROC切点分别为5.4%与5.5%。HbA_1c联合FPG筛查糖尿病与OGTT诊断结果的吻合度有统计学意义(P<0.001),较单独HbA_1c诊断糖尿病吻合度高。

Objective To evaluate the value of hemoglobin Alc （HbA1 c） and fasting blood glucose （FPG）in screening diabetes and impaired glucose regulation in patients with hyperthyroidism,and identify the optimal HbA1 c cut-off point. Methods A total of 508 hospitalized patients with hyperthyroidism in Endocrinology and Metabolism Department in our hospital were recruited in this study. All the patients underwent OGTT. HbAlc,FPG and 2 hPG were tested. Height and weight were measured,and BMI was calculated. ROC curve was made to identify the optimal HhAlc cut-off and positive likelihood ratio （＋LR） and negative likelihood ratio （--LR）. Results The levels of HbA1 c increased gradually with statistical difference in NGT group, IGR group and DM group [ （5.3±0. 2）% vs （5.5 ± 0. 3）% vs （6.0 ± 0. 4）%,P〈0. 001]. According to ROC curve, the optimal cut-off point of HbA1 e in the diagnosis of IGR was 5.4%,while the sensitivity was 55.9% and the specificity was 64. 39%. The optimal cut-off point of HbA1 c for the diagnosis of diabetes（DM） in patients with hyperthyroidism was 5.5 %, while the sensitivity was 79.71% and the specificity was 73.16%. Conclusion HbAlc can correctly reflect the different glucose metabolism in patients with hyperthyroidism. The optimal cut-off point of HbA1 c for screening IGR and DM is 5.4% and 5.5%, respectively. The coincidence degree between HbAlc combined with FPG and OGTT is statistically significant in the diagnosis of DM（P〈0. 001）. The coincidence degree was higher in HbA1 c combined with FPG than HbA1 c alone.