Association of NT-proBNP Concentration in Early Pregnancy with Development of Hypertensive Disorders of Pregnancy

It is important to monitor a woman’s health throughout her pregnancy to determine the potential for adverse pregnancy outcomes (APOs) such as hypertensive disorders of pregnancy, preterm birth, and weighing small for gestational age. 

As a woman’s body transforms during gestation to support the development of the fetus, brain natriuretic peptides and N-terminal pro–brain natriuretic peptides (NT-proBNP) are secreted by left ventricular cardiac myocytes in response to increased wall tension. 

These natriuretic peptides are believed to be strong detectors of subclinical cardiac dysfunction. However, there is little research that examines the concentration of NT-proBNP early in gestation, as previous studies involving NT-proBNP evaluate concentration levels at later stages such as the diagnosis of hypertensive disorders, postpartum recovery, or following an echocardiogram. 

In collaboration with colleagues from other institutions, Alisse Hauspurg, MD, Hyagriv N. Simhan, MD, and Janet M. Catov, PhD, all of Magee-Womens Research Institute, conducted a study to determine if NT-proBNP concentration in early pregnancy is associated with the development of hypertensive disorders of pregnancy and future postpartum hypertension. 

Data was collected from 4,103 nulliparous women with singleton pregnancies who had no pre-pregnancy hypertension or diabetes. Participants from eight clinical centers in the U.S. provided a nonfasting blood sample in the first trimester, attended three study visits prior to delivery, and agreed to follow-up two to seven years after pregnancy.

Results showed that 909 of the 4,103 women (22.2%) experienced an APO during their pregnancy. These women had lower NT-proBNP concentrations in early pregnancy than those who did not develop an APO. 

Preeclampsia was associated with lower NT-proBNP concentrations, with women with preterm preeclampsia having the lowest concentration of NT-proBNP. However, there was no association of NT-proBNP concentration with risk of preterm birth or weighing small for gestational age.

817 of the 4,103 women (19.9%) had hypertension at the follow-up visit. Experts evaluated whether early pregnancy NT-proBNP concentrations differed by hypertension stage at follow-up. 

Women with stage 2 hypertension had the lowest concentrations of NT-proBNP in early pregnancy, women with stage 1 hypertension had intermediate concentrations, and women without hypertension at follow-up had the highest concentrations of NT-proBNP in early pregnancy. 

Therefore, experts determined that higher NT-proBNP concentrations in early pregnancy are associated with a lower risk of hypertensive disorders of pregnancy and a lower risk of hypertension at two to seven years postpartum.

Ultimately, it is believed that the concentration of NT-proBNP serves as an important determinant of both pregnancy outcome and future cardiovascular risk in women. 

Read the full study here.

Reference

Hauspurg A, Marsh DJ, McNeil RB, et al. Association of N-Terminal Pro–Brain Natriuretic Peptide Concentration in Early Pregnancy With Development of Hypertensive Disorders of Pregnancy and Future Hypertension. JAMA Cardiol. 2022;7(3):268–276. doi:10.1001/jamacardio.2021.5617