The use of biomarkers at the end of the second trimester to predict Gestational Diabetes Mellitus

Previous studies that investigated the relationship between biomarkers and gestational diabetes mellitus (GDM) generally focused on individual biomarkers with significant heterogeneity in terms of the screening methodologies, diagnostic criteria for GDM and sample handling of glucose within these studies. This prospective study used an established panel of ten biomarkers to determine if they could predict the diagnosis of GDM.Women with risk factors for GDM were recruited at their first antenatal visit. They attended for an oral glucose tolerance test at 26-28 weeks' gestation with strict preanalytical handling of glucose samples to minimise glycolysis. A fasting plasma sample taken simultaneously was stored at -80 °C and analysed in bulk for 10 biomarkers (insulin, c-peptide, glucagon, ghrelin, gastric inhibitory polypeptide (GIP), glucagon like peptide-1 (GLP-1), leptin, visfatin, resistin and plasminogen activator inhibitor-1 (PAI-1)) using the Bio-plex-pro Human Diabetes Assay.Insulin and C-peptide levels in the third tertile were associated with the development of GDM (adjusted odds ratio (aOR) 2.6, 95 % CI 1.3-5.0, p = 0.005 and aOR 3.7, 95 % CI 1.8-7.4, p 0.001 respectively, adjusted for maternal obesity). Elevated levels of ghrelin were associated with a lower odds of developing GDM, after adjustment for maternal obesity. However, approximately half of the women with GDM who were in the obesity category did not have insulin or c-peptide levels in the third tertile.While three of the ten biomarkers were statistically associated with an increased risk of GDM, the large overlap in values between those with normal and abnormal glucose tolerance meant that the biomarkers (alone or in combination) were not useful clinically.