Abstract
Objectives: The objective of this study is to evaluate agreement between PlGF and sFlt-1/PlGF ratio tests and compare their predictive accuracy for pre-eclampsia in high-risk women. Also, to examine for associations of abnormal PlGF or sFlt-1/PlGF ratio with abnormal uterine artery Doppler and platelet response to aspirin.
Methods: Prospective cohort study, 150 pregnant women at high risk of pre-eclampsia prescribed 75 mg aspirin daily. Uterine artery Dopplers were assessed at 20+0–23+6 weeks. At 33+0–35+6 weeks platelet function aspirin metabolites, PlGF and the sFlt-1/PlGF ratio were measured.
Outcome: Measures were all pre-eclampsia and pre-eclampsia requiring delivery prior to 37 weeks.
Results: Overall percent agreement was 89.3% for PlGF tests but 74.7–78% for PlGF tests and the sFlt-1/PlGF ratio. AUCs were 0.70–0.75 for prediction of any pre-eclampsia and 0.92–0.99 for preterm pre-eclampsia. We found a significant association between abnormal PlGF or sFlt-1/PlGF ratio and abnormal uterine artery Doppler (χ2 5.47, p = .019), but no association with platelet response to aspirin (χ2 0.12, p = .913). There were no associations between suboptimal aspirin adherence and either abnormal angiogenic markers or uterine artery Dopplers (χ2 0.144, 0.038, p = .704, .846, respectively).
Conclusions: There was good agreement between PlGF tests and limited agreement between PlGF tests and the sFlt-1/PlGF ratio. All tests have heightened predictive accuracy for preterm pre-eclampsia. Abnormal PlGF or sFlt-1/PlGF ratio relates to abnormal uterine artery Doppler but not platelet response to aspirin.
Acknowledgements
The authors thank Wellbeing of Women who provided a Research Training Fellowship for Dr Kate Navaratnam.
Disclosure statement
Roche Diagnostics Limited provided the sFlt-1 kits for this analysis free of charge. Roche did not influence the conduct of the study, analyses or content of the manuscripts.