Association between NT-proBNP and Persistent Postpartum Hypertension among Individuals with Hypertensive Disorders of Pregnancy

Abstract This study aimed to evaluate the association of N-terminal pro B-type natriuretic peptide (NT-proBNP) concentration during the delivery hospitalization with persistence of postpartum hypertension and postpartum blood pressure (BP) trajectory among individuals with hypertensive disorders of pregnancy (HDP). This was a single-site cohort study including individuals with new-onset HDP who participated in a remote BP monitoring program and an obstetric biobank. Postpartum BP data were collected from the delivery hospitalization, remote monitoring program, and outpatient visits. Correlations between log(NT-proBNP) and BP values were assessed, and outcomes were compared between low-NT-proBNP (defined as less than 150 pg/mL based on previously published reference intervals in pregnancy) and high-NT-proBNP (greater than or equal to 150 pg/mL) groups. A total of 111 individuals were included, with 31 (27.9%) in the low-NT-proBNP group and 80 (72.1%) in the high-NT-proBNP group. Log(NT-proBNP) had a weakly positive correlation with maximum postpartum systolic (SBP) and diastolic BP (DBP) during the delivery hospitalization. Persistent postpartum hypertension, defined as antihypertensive medication or stage two hypertension at 6 weeks postpartum, occurred in 40.0% of the high-NT-proBNP group versus 19.4% of the low-NT-proBNP group (p = 0.04). The high-NT-proBNP group also had significantly different maximum postpartum DBP during the delivery hospitalization (101 vs. 94 mm Hg, p = 0.01), maximum SBP during remote monitoring (145 vs. 139 mm Hg, p = 0.049), and likelihood of being on antihypertensive medication at 6 weeks postpartum (31.3 vs. 12.9%, p = 0.048) and at any time between delivery and 6 weeks postpartum (48.8 vs. 22.6%, p = 0.01) compared with the low-NT-proBNP group. The high- versus low-NT-proBNP groups had significantly different SBP trajectories over the first 14 days postpartum, with the greatest difference noted in the first 3 to 4 days. NT-proBNP measurement among individuals with HDP at the time of delivery may be useful in assessing risk for persistent postpartum hypertension.