Circulating Angiogenic Factor Levels in Hypertensive Disorders of Pregnancy

Abstract

BackgroundAmong women with hypertensive disorders of pregnancy, biomarkers may stratify risk for developing preeclampsia with severe features (sPE).MethodsAcross 18 U.S. centers, we prospectively measured the ratio of serum soluble fms-like tyrosine kinase 1 (sFlt-1) to placental growth factor (PlGF) in pregnant women hospitalized between 23 and 35 weeks of gestation. The primary outcome was predicting sPE, and secondary outcomes included predicting adverse outcomes within 2 weeks. The prognostic performance of the sFlt-1:PlGF ratio was assessed by using a derivation/validation design.ResultsA total of 1014 pregnant women were evaluated; 299 were included in the derivation cohort and 715 in the validation cohort. In the derivation cohort, the median sFlt-1:PlGF ratio was 200 (interquartile range, 53 to 458) among women who developed sPE compared with 6 (interquartile range, 3 to 26) in those who did not (P<0.001). The discriminatory ratio of ≥40 was then tested in the validation cohort and yielded a 65% positive (95% confidence interval [CI], 59 to 71) and a 96% negative (95% CI, 93 to 98) predictive value for the primary outcome. The ratio performed better than standard clinical measures (area under the receiver-operating characteristic curve, 0.92 versus <0.75 for standard-of-care tests). Compared with women with a ratio <40, women with a ratio ≥40 were at higher risk for adverse maternal outcomes (16.1% versus 2.8%; relative risk, 5.8; 95% CI, 2.8 to 12.2).ConclusionsIn women with a hypertensive disorder of pregnancy presenting between 23 and 35 weeks of gestation, measurement of serum sFlt-1:PlGF provided stratification of the risk of progressing to sPE within the coming fortnight. (Funded by Cedars-Sinai Medical Center and Thermo Fisher Scientific; ClinicalTrials.gov NCT03815110.)