(328) Activin A as a marker of postpartum hypertension following a hypertensive disorder of pregnancy.

Activin A is a pleotropic protein and marker of endothelial dysfunction and cardiac fibrosis in pregnant and non-pregnant individuals. We sought to assess the relationship between maternal serum activin A concentration at delivery, severity of hypertensive disorder of pregnancy (HDP) and postpartum blood pressure (BP) following a HDP.

Study Design:

We conducted a cohort study of individuals with a HDP who delivered between 3/2019 and 3/2022 co-enrolled in our institution’s biospecimen repository and our remote (BP) monitoring program. Eligible individuals had a physician adjudicated HDP diagnosis, no pre-pregnancy hypertension, a serum specimen collected at the time of delivery and reported at least five home BPs in the first six weeks postpartum. Serum activin A was measured by R&D Systems ELISA. Aspirin use during pregnancy was ascertained from the medical record. We used nonparametric Spearman correlations to compare activin concentrations and continuous variables and Wilcoxon rank sum and non-parametric test for trend to compare concentrations across categorical variables.

Results:

We included 76 individuals who contributed 2121 home BPs to this analysis. Maternal serum activin concentration increased in a stepwise fashion with severity of HDP (non-parametric test for trend p< 0.01) but did not differ significantly by aspirin use in pregnancy. Activin concentration was also significantly correlated with peak systolic (r:0.33, p< 0.01) and diastolic (r: 0.24, p=0.03) postpartum BP, but was not correlated with pre-delivery peak systolic (r: 0.11, p=0.35) or diastolic BP (r: 0.06, p=0.58). Individuals requiring initiation of anti-hypertensive medications had higher activin concentrations compared to those never requiring medications (p=0.001).

Conclusion:

In our study, higher serum activin concentrations at the time of delivery were related to increasing severity of HDP, higher peak postpartum BP and need for anti-hypertensive medication. Our results suggest the potential of activin A as a promising biomarker for improving postpartum risk stratification among individuals with HDP.