Higher NT-proBNP Level in Early Pregnancy Linked to Lower Risk of HDP, Hypertension

Alisse Hauspurg, MD

New research investigated the association of future cardiovascular disease with hypertensive disorders of pregnancy (HDP) and the role of natriuretic peptides in detecting subclinical cardiac dysfunction following pregnancy.

The results of the cohort study found higher N-terminal pro-brain natriuretic peptide (NT-proBNP) concentrations throughout early pregnancy were associated with a lower risk of HDP and hypertension 2 - 7 years postpartum.

“In this cohort study, contrary to our hypothesis, we demonstrated that higher NT-proBNP concentrations in early pregnancy were associated with a lower risk of HDP,” said study author Alisse Hauspurg, MD, Magee-Womens Research Institute, University of Pittsburgh School of Medicine.

The Study

The study used data from the Nulliparous Pregnancy Outcomes Study: Monitoring Mothers-to-Be (nuMoM2b) Heart Health study (HHS), which enrolled women from 8 centers in the US.

Women were eligible for enrollment if they had a viable singleton gestation, no previous pregnancy that lasted more than 20 weeks of gestation, and were between 6 and less than 14 weeks of gestation at enrollment.

After delivery, interviews were performed at 6-month intervals to update health status and schedule an in-person cardiovascular assessment ≥2 years after delivery. Self-reported data on race and ethnicity were collected.

Exposures in the study were NT-proBNP concentration measured using an electrochemiluminescence immunoassay from a first-trimester blood sample. Main outcomes were considered HDP and incident hypertension (systolic blood pressure of 130 mm HG or diastolic blood pressure of 80 mm Hg) at follow-up.

A total of 4508 women attended the nuMoM2b Heart HHS follow-up visit at an interval of 2 - 7 years after their delivery that occurred during the nuMoM2b study. For the analysis, exclusions left 4103 women eligible.

Findings

Out of the women included in the analysis, 909 of 410 (22.2%) had an adverse pregnancy outcome (APO) and were more likely to self-report race and ethnicity as non-Hispanic Black.

Data show women who had an APO had lower NT-proBNP concentration in early pregnancy compared to those that did not develop an APO (median, 56.0 pg/mL versus 63.0 pg/mL, P <.001).

Further, higher NT-proBNP concentrations were associated with a lower risk of HDP (adjusted OR per doubling, 0.81; 95% CI, 0.73 - 0.91), which investigators noted persisted after adjustment for age, self-reported race and ethnicity, early-pregnancy body mass index, smoking, and aspirin use.

Additionally, 817 (19.9%) met criteria for stage 1 hypertension of greater, while 49 (1.2%) self-reported the use of antihypertensive medication at the follow-up visit 2 - 7 years postpartum.

Women with incident hypertension at the follow-up had lower NT-proBNP concentration in early pregnancy compared with women without hypertension (median, 54.0 pg/mL versus 64.0 pg/mL, P <.001).

A higher NT-proBNP concentration in early pregnancy was additionally associated with a lower risk of incidence hypertension 2 - 7 years after delivery (adjusted OR per doubling, 0.84; 95% CI, 0.77 - 0.93). The association continued after controlling for confounders such as HDP.

Takeaways

"Taken together, these findings suggest that early-pregnancy cardiovascular physiology, as assessed with NT-proBNP concentration, may be an important determinant of both pregnancy outcome as well as future CVD,” investigators concluded.

The study, “Association of N-Terminal Pro–Brain Natriuretic Peptide Concentration in Early Pregnancy With Development of Hypertensive Disorders of Pregnancy and Future Hypertension,” was published in JAMA Cardiology.