AT1AA have been shown to play a role in endothelial dysfunction, which is a key factor in the pathogenesis of PE. AT1-AA have been shown to mediate disease and thus may have a role as a biomarker.
Objectives
Assess the longitudinal changes and utility of AT1-AA as a biomarker in hypertensive disorders of pregnancy (gestational hypertension [GHT] and preeclampsia [PE]).
Methods
An observational, longitudinal case control study of an unselected population was undertaken. Plasma samples were collected at weeks 12, 18, 28, 36, 40 and 6 weeks post-partum. Baseline clinical, demographic data and pregnancy outcomes were prospectively collected. Pregnancy outcomes included normotensive (control), GHT or PE. AT1-AA were measured using a validated commercial ELISA (One-Lambda). Statistical analyses were carried out using SPSS, data expressed as median (interquartile range] and statistical significance was set at p <0.05.
Result
351 women were recruited, 17 and 18 developed GHT and PE respectively. AT1AA levels were measured in 76 women. Maternal age was similar for all three groups. There was a statistically significant difference in maternal weight (p = 0.015), height (p = 0.046) and BMI (p = 0.041) between groups (Kruskal-Wallis test). Baseline systolic and diastolic blood pressure was significantly different across groups with p values of 0.029 and 0.006 respectively (Kruskal–Wallis). The PE group had higher rate of preeclampsia history 28.1% compared to controls 1.3% p <0.01. There was no significant difference in the rate of smoking, primiparity and gestational diabetes mellitus (GDM). AT1-AA levels decreased from 12 weeks 15.44[12.77–17.86] u/ml to term 11.53[5.75–17.78] u/ml but this was not statistically significant. There was no difference in AT1AA between the three diagnostic groups at any time point (Kruskal–Wallis analysis analysis p >0.05) (Fig. 1). AT1AA at 12 weeks had a positive correlation with serum PAPP-A (p = 0.008) and BHCG (p = 0.04) but no relationship with other angiogenic markers at 12 weeks such as soluble fms like tyrosine kinase receptor 1, plasma like growth factor or serum endogolin. AT1AA at 12 weeks was not associated with later preeclampsia (p = 0.25).
Conclusions
AT1AA are not specific for PE and do not prove to be biomarkers of disease.
