Comparison of the Soluble fms-Like Tyrosine Kinase 1/Placental Growth Factor Ratio Alone versus a Multi-Marker Regression Model for the Prediction of Preeclampsia-Related Adverse Outcomes after 34 Weeks of Gestation.

INTRODUCTION: The objective of this retrospective study was to compare the predictive performance of the soluble fms-like tyrosine kinase 1 (sFlt-1)/placental growth factor (PlGF) ratio alone or in a multi-marker regression model for preeclampsia-related maternal and/or fetal adverse outcomes in women >34 weeks of gestation. METHODS: We analyzed the data collected from 655 women with suspected preeclampsia. Adverse outcomes were predicted by multivariable and univariable logistic regression models. The outcome of patients was evaluated within 14 days after presentation with signs and symptoms of preeclampsia or diagnosed preeclampsia. RESULTS: The full model integrating available, standard clinical information and the sFlt-1/PlGF ratio had the best predictive performance for adverse outcomes with an AUC of 72.6%, which corresponds to a sensitivity of 73.3% and specificity of 66.0%. The positive predictive value of the full model was 51.4%, and the negative predictive value was 83.5%. 24.5% of patients, who did not experience adverse outcomes but were classified as high risk by sFlt-1/PlGF ratio (≥38), were correctly classified by the regression model. The sFlt-1/PlGF ratio alone had a significantly lower AUC of 65.6%. CONCLUSIONS: Integrating angiogenic biomarkers in a regression model improved the prediction of preeclampsia-related adverse outcomes in women at risk after 34 weeks of gestation.

Correlation between placental weight and angiogenic markers sFlt-1 and PlGF in women with preeclampsia and fetal growth restriction.

OBJECTIVES: The angiogenic factors sFlt-1 (soluble fms-like tyrosine kinase) and PlGF (Placental Growth Factor) play a key role in the pathophysiology, prediction and diagnosis of preeclampsia-associated pregnancy disorders. However, the correlation between maternal serum levels and the placental weight, especially in hypertensive pregnancy disorders is still unclear. STUDY DESIGN: Retrospectively, we analyzed data from a real-world cohort of patients with preeclampsia (PE), intrauterine growth restriction (IUGR), PE + IUGR and controls giving birth within 14 days from inclusion. Herein, correlational analyses were calculated between placental weight, maternal serum levels of sFlt-1, PlGF and the respective sFlt-1/PlGF-ratios. MAIN OUTCOME MEASURES AND RESULTS: This study included n = 328 patients (n = 134 with PE, n = 40 with IUGR and n = 25 showed PE + IUGR) and n = 129 controls. The gestational age-adjusted placental weight was significantly decreased in patients with PE ± IUGR, but not in PE alone, when comparing to controls. Correlation between PlGF and the placental weight was significantly positive and increasing with severity of disease (controls 0.134, p = 0.131, PE 0.419, p < 0.01, IUGR 0.517, p < 0.01, PE + IUGR r = 0.723, p < 0.01). Furthermore, an inverse correlation between the sFlt-1/PlGF-ratio and the placental weight was found. The sFlt-1/PlGF-ratio per gram placental weight was highest in patients with PE + IUGR and lowest in controls (0.6 (IQR 0.4-1.8) vs. 0.05 (IQR 0.02-0.15)). CONCLUSION: A correlation between the serum levels of sFlt-1 and PlGF and the placental weight is present in PE-associated pregnancy disorders. This mirrors the model of an angiogenic continuum in the placenta where the serum sFlt-1 to PlGF ratio increases with severity of the disease.