探讨上海朱泾地区孕妇不同孕期空腹血糖(FGP)及晚孕期糖化血红蛋白(HbA1c)的特点。

选择2014年1月1日至12月31日，在上海市第六人民医院金山分院接受产前检查并进行75 g口服葡萄糖耐量试验(OGTT)筛查的606例孕妇为研究对象。按照75 g OGTT筛查结果，将其分为妊娠期糖尿病(GDM)组(n＝136)和非GDM组(n＝470)。采用回顾性分析方法，采集2组受试者的年龄、人体质量指数(BMI)等一般临床资料，以及2组孕妇早、中、晚孕期FPG浓度和晚孕期HbA1c水平。根据四分位数法，将所有受试者晚孕期HbA1c水平划分为4个范围：Q1(HbA1c值<5.1%)、Q2(5.1%≤HbA1c值<5.2%)、Q3(5.2%≤HbA1c值<5.5%)和Q4(HbA1c值≥5.5%)。采用成组t检验，比较2组孕妇的年龄、BMI、不同孕期FPG浓度和晚孕期HbA1c水平。采用χ²检验，对晚孕期HbA1c水平处于不同范围的所有受试者的GDM发生率进行整体比较，而进一步的两两比较，则调整检验水准后再进行比较。绘制晚孕期HbA1c水平预测GDM发生的受试者工作特征(ROC)曲线，计算ROC曲线下面积(ROC-AUC)，根据约登指数最大原则，确定晚孕期HbA1c水平预测GDM发生的最佳临界值，同时计算预测GDM发生的敏感度、特异度。本研究符合2013年修订的《世界医学协会赫尔辛基宣言》。

①GDM组孕妇的年龄、BMI均大于对照组，并且差异均有统计学意义(t＝5.306、5.250，P<0.001)。GDM组孕妇中，中孕期FPG浓度最高，为(4.9±0.6)mmol/L，中孕期FPG浓度高于早、晚孕期FPG浓度，并且差异均有统计学意义(t＝2.087、1.960，P＝0.039、0.041)。非GDM组孕妇中，早孕期FPG浓度最高，为(4.7±0.3)mmol/L，早孕期FPG浓度高于中、晚孕期FPG浓度，并且差异亦均有统计学意义(t＝15.230、5.613，P<0.001)。GDM组孕妇早、中、晚孕期FPG浓度均分别高于对照组，并且差异均有统计学意义(t＝5.416、15.526、4.471，P<0.001)。GDM组孕妇晚孕期HbA1c水平为(5.6±0.4)%，明显高于非GDM组的(5.4±0.4)%，2组比较，差异亦有统计学意义(t＝22.707，P<0.001)。②HbA1c水平处于不同范围的所有受试者的GDM发生率整体比较，差异有统计学意义(χ²＝22.707，P<0.001)。进一步对GDM发生率进行两两比较的结果显示，HbA1c水平处于Q1、Q2范围的受试者的GDM发生率，均低于处于Q4范围的受试者的GDM发生率，差异均有统计学意义(χ²＝15.071，16.785，P<0.001)。③ROC曲线分析结果显示，晚孕期HbA1c水平预测GDM发生的ROC-AUC为0.647(95%CI：0.625～0.672，P<0.001)。根据约登指数最大原则，晚孕期HbA1c水平预测GDM发生的最佳临界值为5.5%，此时其预测GDM发生的敏感度为63.4%，特异度为69.7%。

上海朱泾地区GDM孕妇FPG浓度从早孕期即开始升高，在中孕期达到高峰，经过对其生活方式进行干预后，在晚孕期有所下降。GDM孕妇晚孕期HbA1c水平建议控制在5.5%以下为宜。

To investigate features of fasting plasma glucose (FPG) during different trimesters and hemoglobin A1c (HbA1c) in the third trimester of pregnant women in Zhujing Region of Shanghai.

A total of 606 cases of pregnant women who received prenatal examination and 75 g oral glucose tolerance test (OGTT) in Jinshan Branch of Shanghai Sixth People′s Hospital from January 1 to December 31, 2014 were collected as research subjects. According to the results of 75 g OGTT, they were divided into gestational diabetes mellitus (GDM) group (n=136) and non-GDM group (n=470). The clinical data, such as age, body mass index (BMI), as well as the concentration of FPG during different pregnancy trimesters and level of HbA1c in the third trimester were collected retrospectively in both two groups by retrospective analysis method. According to the quartile method, level of HbA1c in the third trimester of all subjects were divided into four ranges: Q1 (HbA1c level<5.1%), Q2 (5.1%≤HbA1c level<5.2%), Q3 (5.2%≤HbA1c level<5.5%), and Q4 (HbA1c level≥5.5%), respectively. The age, BMI, concentrations of FPG and the level of HbA1c between two groups were compared by independent-samples t test. Chi-square test was used to compare the GDM incidence of all subjects with different ranges of HbA1c level in the third trimester, and further comparison was conducted by adjusting inspection level. Then receiver operator characteristic (ROC) curve of HbA1c level in the third trimester for predicting the incidence of GDM was drawn, and the area under ROC curve (ROC-AUC) was calculated. The optimal critical value of HbA1c level in the third trimester for predicting the incidence of GDM was obtained when the Youden index reaching the maximum value. And its sensitivity and specificity were calculated. This study met the requirements of the World Medical Association Declaration of Helsinki revised in 2013.

①The age and BMI of GDM group were higher than those in non-GDM group, and there were statistically significant differences (t=5.306, 5.250; P<0.001). Among the subjects in GDM group, the concentration of FPG in second trimester was the highest among 3 trimesters, which was (4.9±0.6) mmol/L, and the concentration of FPG in second trimester was higher than that in first and third trimester, respectively, and both the differences were statistically significant (t=2.087, 1.960; P=0.039, 0.041). Among the subjects in non-GDM group, the concentration of FPG in first trimester was the highest among 3 trimesters, which was (4.6±0.3) mmol/L, and the concentration of FPG in first trimester was higher than that in second and third trimester, respectively, and both the differences were statistically significant (t=15.230, 5.613; P<0.001). The concentration of FPG in first, second and third trimesters of GDM group were higher than those of non-GDM group, respectively, and there were statistically significant differences (t=5.416, 15.526, 4.471; P<0.001). Besides, HbA1c level in third trimester of GDM group was (5.6±0.4)%, which was higher than that of non-GDM group (5.4±0.4)%, and there was significant difference (t=5.845, P<0.01). ②There was statistical difference in GDM incidences in all subjects with different ranges of HbA1c levels in third trimester (χ²=22.707, P<0.001). Multiple comparison results showed that the incidences of GDM in all subjects with Q1 and Q2 ranges of HbA1c levels in third trimester were higher than that in subjects with Q4 range of HbA1c levels in third trimester, respectively, and both the differences were statistically significant (χ²=15.071, 16.785; P<0.001). ③The results of ROC curve analysis of HbA1c level in third trimester in predicting the incidence of GDM showed that the ROC-AUC was 0.647 (95%CI: 0.625-0.672, P<0.001), and the optimal cut-off value of HbA1c level in third trimester to predict GDM incidence was 5.5%, and the sensitivity of HbA1c level in predicting the incidence of GDM was 63.4%, and the sensitivity was 69.7%.

The concentrations of FPG in GDM pregnant women in Zhujing Region of Shanghai begin to increase from the first trimester and peak during the second trimester, and decrease during the third trimester after lifestyle intervention. It is advisable for GDM pregnant women to control HbA1c levels below 5.5% during the third trimester.