Midpregnancy prediction of pre-eclampsia using serum biomarkers sFlt-1 and PlGF

Objectives: Pre-eclampsia remains a significant cause of morbidity and mortality. Placental biomarkers soluble Fms-like tyrosine kinase-1 (sFlt-1) and placental growth factor (PlGF) have been investigated previously for their ability to predict pre-eclampsia. We compared the performance of these biomarkers for midpregnancy pre-eclampsia prediction using three different immunoassay platforms. Study design: Prospective study including singleton pregnancies 19-22 weeks' gestation. Maternal bloods were collected at recruitment. Screening performances using receiver operating characteristic (ROC) curves for PlGF and sFlt-1/PlGF ratio raw data and MoM values in isolation were evaluated for three immunoassay platforms using selected cut-off values. Main outcome measures: Pre-eclampsia was defined as early-onset (< 34 weeks' at delivery) and preterm (< 37 weeks' at delivery). Results: For prediction of preterm pre-eclampsia, PlGF MoM and sFlt-1/PlGF ratio MoM performed similarly, with areas under the curve (AUC), detection rates (DR) and false positive rates (FPR) for PlGF MoM and sFlt-1/PlGF ratio MoM being 0.77-0.79 and 0.71-0.74, 62.5% for both and 9.7-14.9 and 10.7-17.7, respectively. For the prediction of early-onset pre-eclampsia, sFlt-1/PlGF ratio raw data and MoM values performed similarly, with AUC, DR and FPR being 0.92-0.97 and 0.93-0.96, 100% for both, and 4.13-16.9 and 9.4-12.2, respectively. Conclusions: For midpregnancy prediction of preterm pre-eclampsia, PlGF MoM for all three platforms and sFlt-1/PlGF ratio MoM for the two platforms that tested sFlt-1 performed similarly. For midpregnancy prediction of early-onset pre-eclampsia at midpregnancy, sFlt-1/PlGF ratio raw data and MoM values using the earlyonset cut-off for the two platforms that tested sFlt-1 gave similar performance from a clinical perspective.