Placental discrepancies between Black and White patients with preeclampsia in a southeastern US cohort

Preeclampsia is a devastating hypertensive disorder of pregnancy with a high prevalence in the southern regions of the United States. Black pregnant patients are disproportionally at higher risk for preeclampsia onset and severity of disease than other racial groups. The underlying mechanism(s) for this racial disparity are unclear. In our current study, we were able to obtain a cohort of patients of self-identifying Black or White race who were overall matched for body mass index (BMI), blood pressure, gestational and maternal age, and parity, and we hypothesized that placentas from Black patients with preeclampsia would demonstrate elevated preeclampsia-associated placental gene expressions compared with White patients with preeclampsia. We collected placenta tissue from both healthy individuals and preeclampsia Black and White patients (n = 13-17) who delivered in Augusta, GA. We measured expressions of several preeclampsia-implicated genes and performed placental morphological analysis and bulk RNA sequencing. Contrary to our hypothesis, ddPCR analysis demonstrated that leptin, preproendothelin-1 (PPET-1), endothelial converting enzyme-1 (ECE-1), and soluble FMS-like tyrosine kinase-1 (sFlt-1) were higher in White preeclamptic women than in Black preeclamptic women. Our RNA sequencing analysis revealed that 288 genes differed between healthy Black individuals and preeclamptic Black patients. A striking 2,394 gene expressions significantly differed between healthy and preeclamptic White patients. Placental histology analysis revealed that Black patients with preeclampsia demonstrated a lower scoring of morphological pathologies associated with preeclampsia compared with White patients with preeclampsia. Collectively, these data indicate that gene expressions and placental injury markers associated with preeclampsia are more pronouncedly elevated in White patients compared with Black patients.NEW & NOTEWORTHY Black patients in United States are at a discrepant high risk for preeclampsia, via mechanisms unknown. We found that White patients with preeclampsia had significantly higher changes in gene and placental morphological expressions compared with healthy pregnancy than observed in Black patients with preeclampsia. These data indicate that placental damage in preeclampsia in our cohort was less evident in Black patients with preeclampsia compared with White patients with preeclampsia and that nonplacental mechanisms for disease may be predominate in Black patients with preeclampsia.