BackgroundThe management of potential pre-eclamptic patients using the soluble FMS-like tyrosine kinase 1 (sFlt-1)/ placental growth factor (PlGF) ratio is characterised by frequent false-positive results.MethodsA retrospective cohort study was conducted to identify and validate cut-off values, obtained using a machine learning model, for the sFlt-1/PlGF ratio and NT-proBNP that would be predictive of the absence or presence of early-onset pre-eclampsia (PE) in singleton pregnancies presenting at 24 to 33 + 6 weeks of gestation.ResultsFor the development cohort, we defined two sFlt-1/PlGF ratio cut-off values of 23 and 45 to rule out and rule in early-onset PE at any time between 24 and 33 + 6 weeks of gestation. Using an sFlt-1/PlGF ratio cut-off value of 23, the negative predictive value (NPV) for the development of early-onset PE was 100% (95% confidence interval [CI]: 99.5–100). The positive predictive value (PPV) of an sFlt-1/PlGF ratio >45 for a diagnosis of early-onset PE was 49.5% (95% CI: 45.8–55.6). When an NT-proBNP value >174 was combined with an sFlt-1/PlGF ratio >45, the PPV was 86% (95% CI: 79.2–92.6). In the validation cohort, the negative and positive values were very similar to those found for the development cohort.ConclusionsAn sFlt-1/PlGF ratio <23 rules out early-onset PE between 24 and 33 + 6 weeks of gestation at any time, with an NPV of 100%. An sFlt-1/PlGF ratio >45 with an NT-proBNP value >174 significantly enhances the probability of developing early-onset PE.

The addition of NT-proBNP assessment improves the short-term prediction of delivery as a result of PE compared with sFlt-1/PlGF ratio alone, when the sFlt-1/PlGF ratio is > 38. This finding should be considered in future research on the assessment of short-term risk of delivery as a result of PE. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Objectives Studies of cardiovascular function in pregnancy have shown inconsistent and, in some cases, contradictory results, particularly regarding cardiac output. While some studies report preeclampsia associated with high cardiac output, other studies suggest that preeclampsia should be further subdivided into women with high or low cardiac output. This study was conducted to examine the NT-proBNP levels in preeclampsia, intrauterine growth restriction, and hypertensive pregnancies without preeclampsia. We also examined N-terminal pro-B natriuretic peptide (NT-proBNP) levels three to four months after delivery, in preeclamptic women as well as the prediction of delivery within 10 days. In a reduced number of preeclamptic women and controls we performed echocardiograms to study their diastolic function. Methods We investigated the NT-proBNP levels in 213 subjects with preeclampsia only, 73 with intrauterine growth restriction, 44 with preeclampsia and intrauterine growth restriction, 211 who were hypertensive and 662 unaffected pregnancies (controls). We also performed echocardiograms on 36 preeclampsia and 19 controls before delivery and three to five months after delivery. Results NT-proBNP levels are higher in early onset preeclampsia than in late onset preeclampsia. Intrauterine growth restriction pregnancies showed a NT-proBNP levels similar to hypertensive and unaffected pregnancies. Compared with healthy pregnancies, women with preterm preeclampsia (<37 gestational weeks) had altered left atrial segments. Conclusions We observed that NT-proBNP levels are higher in early onset preeclampsia than in late onset. Moreover, diastolic dysfunction is higher in early onset than in late-onset term preeclampsia. An NT-proBNP value >136 pg/mL has a high positive predictive value for an imminent delivery within 10 days.

Objectives (1) To develop a risk score for early-onset pre-eclampsia leading to delivery within one week from repeated marker determinations on pregnancies with an sFlt-1/PlGF ratio above 38, and (2) to compare it (i) with sFlt-1/PlGF ratio model and (ii) with the sFlt-1/PlGF ratio 655 cutoff. Design Retrospective cohort study. Setting Oviedo, Spain. Sample 522 blood samples from 363 singleton pregnancies with clinical suspicion of pre-eclampsia between 27 and 34 weeks of gestation. Methods NT-proBNP, sFlt-1 and PlGF were combined using linear mixed models with random intercept based on 213 samples from 123 pregnancies with an sFlt-1/PlGF ratio above 38. Main outcome measures Early-onset pre-eclampsia diagnosis leading to delivery within one week from assessment. Results None of the 253 pregnancies with an sFlt-1/PlGF ratio of 38 or below developed early-onset pre-eclampsia. The prognostic prediction tool included sFlt-1 MoM, NT-proBNP and gestational age at time (GA) of repeated measurements. The area under the ROC curve (AUC) for early-onset pre-eclampsia diagnosis leading to delivery within one week was 88.247 (95% CI 0.822-0.934) for the prediction tool and 82.639 (95% CI 0.752-0.892) for the sFlt-1/PlGF + GA model (P=0.04). At an sFlt-1/PlGF ratio 655 cutoff the detection ratio was 31.9% (19.1-47.1) with false positive rate of 4.2% (1.7-8.5). With the same false positive rate, the detection rate with the prognostic prediction tool was 53.2% (38.1-67.9) (P=0.03). Conclusions A prediction tool derived from NT-proBNP, sFlt-1 MoM and gestational age linear mixed model provided clinically useful prediction of early-onset pre-eclampsia prognosis when clinically suspected.

<b><i>Introduction:</i></b> Short-term prediction of pre-eclampsia (PE) using soluble FMS-like tyrosine kinase-1 (sFlt-1)/ placental growth factor (PlGF) ratio has high false-positive rate. Therefore, we developed a prognostic prediction tool that predicts early-onset PE leading to delivery within 1 week on pregnancies with an sFlt-1/PlGF ratio above 38 and compared it with an analogous model based on sFlt-1/PlGF ratio and with the 655 sFlt-1/PlGF ratio cutoff. <b><i>Methods:</i></b> Cohort study of 363 singleton pregnancies with clinical suspicion of PE before 34 weeks of gestation, allowing repeated assessments (522). 213 samples with an sFlt-1/PlGF ratio above 38 were assessed to construct and identify the best-fit linear mixed model. N-terminal pro-B-type natriuretic peptide (NT-proBNP), sFlt-1 MoM, PlGF MoM, and sFlt-1/PlGF ratio combined with gestational age (GA) were assessed. <b><i>Results:</i></b> None of the pregnancies with an sFlt-1/PlGF ratio of 38 or below developed early-onset PE (309 samples from 240 pregnancies). Conversely, 47 women of 213 assessments (22.1%) with an sFlt-1/PlGF ratio above 38 developed the assessed outcome. The selected model included sFlt-1 MoM, NT-proBNP, and GA. Differences in area under the curve were observed between the selected model and the GA + sFlt-1/PlGF model (<i>p</i> = 0.04). At an sFlt-1/PlGF ratio cutoff of 655, detection rate was 31.9% (15/47), while the selected model detection was 55.3% (26/47) (<i>p</i> = 0.008). <b><i>Discussion:</i></b> Considering repeated assessments, the sFlt-1/PlGF ratio of 38 or below adequately ruled out early-onset PE, leading to delivery within 1 week. However, when sFlt-1/PlGF ratio is above 38, the prediction tool derived from linear mixed model based on GA, NT-proBNP, and sFlt-1 MoM, provided a better prognosis prediction than the sFlt-1/PlGF ratio.