Mosca Andrea, Paleari Renata, Dalfrà Maria G, Di Cianni Graziano, Cuccuru Ilaria, Pellegrini Giovanni, Malloggi Lucia, Bonomo Matteo, Granata Simona, Ceriotti Ferruccio, Castiglioni Maria T, Songini Marco, Tocco Giuliana, Masin Michela, Plebani Mario, Lapolla Annunziata
Dipartimento di Scienze e Tecnologie Biomediche, Università degli Studi di Milano, Segrate (Milano), Italy.
Clin Chem. 2006 Jun;52(6):1138-43. doi: 10.1373/clinchem.2005.064899. Epub 2006 Apr 6.
The reference intervals for hemoglobin A1c (Hb A1c) in pregnant women without diabetes are not well defined, and few examples of reference intervals established by networks of different laboratories are available.
Five Italian Diabetic Care Units were involved in the study. Data were collected from 445 pregnant women without diabetes, selected on the basis of glucose challenge test results, and from 384 nonpregnant control women. The Hb A1c measurements were performed with HPLC systems aligned to the Diabetes Control and Complications Trial. Plasma glucose measurements were also performed locally. Both Hb A1c and glucose measurements were harmonized by running appropriate external quality assessment schemes. The reference intervals were calculated in terms of nonparametric 2.5th to 97.5th percentiles with 0.90 confidence intervals.
The Hb A1c measurements were reproducible (CV = 2.0%) and accurate [mean (SE) difference from the target values, -0.10 (0.06)%]. Glucose measurements were also reproducible (mean CV = 3.2%) and accurate [difference from the target values, -0.01 (0.04) mmol/L]. To calculate common reference intervals, we merged the data collected in the different centers. The Hb A1c reference intervals were 4.0%-5.5% for pregnant nondiabetic women and 4.8%-6.2% for nonpregnant controls.
Healthy pregnant women have lower Hb A1c concentrations than nonpregnant women. The reference intervals for Hb A1c in pregnant women should therefore be lower than those currently in use.
无糖尿病孕妇的糖化血红蛋白（Hb A1c）参考区间尚未明确界定，且不同实验室网络建立的参考区间实例较少。
五家意大利糖尿病护理单位参与了该研究。数据收集自445名无糖尿病的孕妇，这些孕妇根据葡萄糖耐量试验结果选取，以及384名非孕对照女性。使用与糖尿病控制和并发症试验校准的高效液相色谱系统进行Hb A1c测量。血浆葡萄糖测量也在当地进行。通过运行适当的外部质量评估方案对Hb A1c和葡萄糖测量进行校准。参考区间根据非参数第2.5至第97.5百分位数计算，置信区间为0.90。
Hb A1c测量具有可重复性（CV = 2.0%）且准确[与目标值的平均（SE）差异为 -0.10（0.06）%]。葡萄糖测量也具有可重复性（平均CV = 3.2%）且准确[与目标值的差异为 -0.01（0.04）mmol/L]。为计算通用参考区间，我们合并了不同中心收集的数据。无糖尿病孕妇的Hb A1c参考区间为4.0% - 5.5%，非孕对照为4.8% - 6.2%。
健康孕妇的Hb A1c浓度低于非孕妇。因此，孕妇的Hb A1c参考区间应低于目前使用的区间。
