Performance of different screening methods on gestational diabetes
Aldana, Paola   (Johns Hopkins University)
Mentor: Turan, Ozhan (University of Maryland-Baltimore)
The most utilized screening test for gestational diabetes (GDM) is the 50 g 1h Oral Glucose Screening Test; however this test has inherent limitations on patient compliance. The utility of HbA1c (A1c) on screening for GDM has not yet been fully established. Preliminary studies have shown that fetal epicardial fat tissue (EFT) increases in fetuses of mothers with pre-gestational diabetes. We hypothesized that fetal EFT measurement will provide accurate information similar to the 1h glucose test and A1c in the screening of GDM. This is a retrospective analysis of prospectively collected data from patients followed in our clinic between January and June 2017. We obtained 1h glucose, A1c and fetal EFT from singleton pregnancies at similar gestational age. The diagnosis of GDM was based on an abnormal 1h glucose screening test followed by a 3h Oral Glucose Tolerance Test. Fetal EFT’s were measured by single blinded observer using a standardized method (Figure 1). In order to eliminate the effects of gestational age on fetal EFT, the EFT values were converted to their multiple of the median (MoM) values, which were calculated using 132 normal patients. Predictive values of the 1h glucose test, A1c and fetal EFT were analyzed using Receiver Operating Curve (ROC) analysis. One hundred forty seven patients were used in our final analysis. GDM was diagnosed in 15 (10%) of them. Demographics of the study population are given in Table 1. The diagnostic performance for each approach was (sensitivity, specificity, AUC): EFT=-0.13mm (40%, 80%, 0.57), 1h glucose>128mg/dl (93%, 86%, 0.96), and A1c >5.5% (80%, 78%, 0.86), respectively. The comparisons of ROC analysis showed that the 1h glucose test was superior to A1c and fetal EFT measurement (p<0.001 and 0.1, respectively) (Figure 2). The 1h glucose test remains the best predictor for the development of GDM. The performance of early 2nd trimester fetal EFT was not acceptable to utilize as a screening test.