The sFlt-1/PlGF ratio and its predictive value concerning time to delivery in patients with preeclampsia – Preliminary Data

Fragestellung/Objective:

The outcome of preeclampsia can't easily be predicted, its severity varies from patient to patient. Laboratory markers like the soluble fms-like tyrosine kinase (sFlt-1) and the placental growth factor (PlGF) are said to be predictive markers. A study of Verlohren evaluated cutoffs determining the predictive value concerning time to delivery in patients with elevated sFlt-1/PlGF ratio. This study compares the above findings in patients with elevated sFlt-1/PlGF ratio delivering at the Kepler University Hospital in Linz. The aim of the study was to find out if the described cutoffs are also an indicator for women at risk for imminent delivery in our patient collective.

Methods:

A retrospective study of all patients with preeclampsia delivering at the Kepler University Hospital in Linz from 1.1.2014 to 31.10.2017 with an elevated sFlt-1/PlGF ratio was performed. We focused on patients showing an sFlt-1/PlGF ratio higher than 655 before 34 weeks of pregnancy (group 1) and higher than 201 between 34 and 37 weeks of pregnancy (group 2). Above all we investigated the time to delivery but also characteristics like mode of birth, induction of labor, former history of preeclampsia and complications like HELLP syndrome or eclampsia.

Results:

In our patient collective we found 31 patients with an elevated sFlt-1/PlGF ratio over 655 before 34 weeks of pregnancy (group 1) and 29 patients with an elevated sFlt-1/PlGF ratio over 201 between 34 und 37 weeks of pregnancy (group 2). In the first group 16 patients delivered their baby within 48h (51,6%), but 15 patients remained pregnant (48,4%). In the second group 12 patients delivered within 48h (41,4%), whereas 17 patients were still pregnant (58,6%). Up to now, only a descriptive analysis has been performed (preliminary data). In future, patients from 2011 – 2013 will also be included. A detailed statistical evaluation will follow.

Conclusion:

The sFlt-1/PlGF ratio does seem to be a predictive tool for assessing the risk of imminent delivery in patients with preeclampsia, however we could not confirm the former evaluated cutoffs. The low number of patients investigated in this study is of course a limitation. Further studies will be needed to assess the predictive value of the sFlt-1/PlGF ratio.