Culliney Katherine, McCowan Lesley M E, Okesene-Gafa Karaponi, Murphy Rinki, Rowan Janet, Taylor Rennae S, Mckinlay Christopher J D
Department of Obstetrics and Gynaecology, University of Auckland, Auckland, New Zealand.
Counties Manukau Health, Auckland, New Zealand.
Aust N Z J Obstet Gynaecol. 2018 Dec;58(6):643-647. doi: 10.1111/ajo.12786. Epub 2018 Feb 22.
In New Zealand, it is recommended that all pregnant women have a haemoglobin A1c (HbA1c) test performed with their booking antenatal bloods to identify previously unrecognised diabetes. However, screening rates in some groups are low. Use of a point-of-care device may improve compliance with screening.
To assess the accuracy of the COBAS b101 point-of-care system referenced against a laboratory method, for measurement of HbA1c levels in pregnant women.
Convenience sample of 40 obese pregnant women enrolled in a clinical trial. HbA1c was assayed in paired capillary and venous whole blood samples using the COBAS b101 point-of-care system and Primus Ultra2 high performance liquid chromatography laboratory analyser, respectively. The accuracy of the point-of-care system was assessed by Bland-Altman analysis.
The mean (SD) laboratory HbA1c was 35.9 (2.0) mmol/mol. The COBAS b101 point-of-care system, compared with the laboratory reference method, had a small negative bias for HbA1c (-1.0 mmol/mol, 95% CI -2.0 to -0.03, P = 0.03) and relatively wide 95% limits of agreement (-7.2 to 5.1 mmol/mol).
In conclusion, we found that in pregnancy, the COBAS b101 point-of-care system has a small negative bias and modest point accuracy for HbA1c. When used to screen for previously unrecognised diabetes in pregnancy, appropriate COBAS b101 HbA1c point-of-care HbA1c thresholds for a negative and positive result are 7 mmol/mol below and 5 mmol/mol above the clinical threshold, respectively. Values between these limits should be confirmed by laboratory testing.
在新西兰，建议所有孕妇在产前首次检查时进行糖化血红蛋白（HbA1c）检测，以识别此前未被诊断出的糖尿病。然而，某些群体的筛查率较低。使用即时检测设备可能会提高筛查的依从性。
评估COBAS b101即时检测系统相对于实验室方法测量孕妇HbA1c水平的准确性。
对40名参与一项临床试验的肥胖孕妇进行便利抽样。分别使用COBAS b101即时检测系统和Primus Ultra2高效液相色谱实验室分析仪对配对的毛细血管全血和静脉全血样本进行HbA1c检测。通过Bland-Altman分析评估即时检测系统的准确性。
实验室检测的HbA1c平均（标准差）值为35.9（2.0）mmol/mol。与实验室参考方法相比，COBAS b101即时检测系统检测HbA1c时存在较小的负偏差（-1.0 mmol/mol，95%可信区间-2.0至-0.03，P = 0.03），一致性界限的95%范围相对较宽（-7.2至5.1 mmol/mol）。
总之，我们发现孕期使用COBAS b101即时检测系统检测HbA1c时存在较小的负偏差，准确性一般。用于筛查孕期未被识别的糖尿病时，COBAS b101即时检测HbA1c结果为阴性和阳性的合适阈值分别比临床阈值低7 mmol/mol和高5 mmol/mol。这些界限之间的值应通过实验室检测确认。
