High NT-proBNP in Early Pregnancy Could Signal Lower HDP, Future Hypertension Risk

This article was originally published on PracticalCardiology.com.

A new study has returned surprising results, suggesting elevated NT-proBNP in early pregnancy was associated with a lower risk of hypertensive disorders and future hypertension.

An analysis of data from more than 4000 women, results of the study suggest higher NT-proBNP concentrations were associated with a lower risk of HDP and hypertension 2-7 years post partum, even after adjustment for variables including age, race, BMI, and lifestyle facts.

“Contrary to our hypothesis, we demonstrated that higher NT-proBNP concentrations in early pregnancy were associated with a lower risk of HDP. This association was present after controlling for early-pregnancy blood pressure and traditional risk factors,” wrote investigators.

Few conditions are associated with as substantial of an increase for risk of future cardiovascular disease as HDPs. With this in mind, investigators sought to determine whether measurements of NT-proBNP could serve as useful markers for subclinical cardiac dysfunction and a predictor of HDP as well as future hypertension risk. Performed on behalf of the NICHD nuMoM2b and NHLBI nuMoM2b Heart Health Study Networks, the study was designed to assess potential associations of NT-proBNP and HDP and future hypertension risk in a cohort of patients from The Nulliparous Pregnancy Outcomes Study: Monitoring Mothers-to-Be Heart Health study.

From the prospective multicenter observational study, investigators were able to identify a cohort of 4103 nulliparous women with complete data and no pregnancy hypertension or diabetes at baseline who were treated at 8 clinical sites in the US. As part of their participation in the study, women provided a nonfasting blood sample in the first trimester, attended study visits at 3 time points prior to delivery, allowed medical records access, and agreed to postpartum follow-up. Follow-up was performed via telephone or email at 6-month intervals beginning at least 6 months after delivery and required patients to undergo an in-person cardiovascular assessment visit at least 2 years after delivery.

The study cohort had a mean age of 27 (SD, 5.6) years. Of the 4103 included in the study, 909 (22.2%) had an adverse pregnancy outcome and 817 (19.9%) had stage 1 hypertension or greater at the follow-up visit. Compared to women without hypertension at follow-up, women who had hypertension were older at baseline, more likely to self-report being non-Hispanic Black, and had higher early-pregnancy BMIs.

Results demonstrated higher NT-proBNP concentrations were associated with a lower risk of HDP (aOR 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 BMI, smoking, and aspirin use. When assessing NT-proBNP and hypertension risk 2-7 years after delivery, results indicated higher NT-proBNP concentrations were associated with a lower risk of incident hypertension (aOR per doubling, 0.84 [95% CI, 0.770.93]), which investigators pointed out was an association that persisted after adjustment for confounders, including HDP.

“Findings from this cohort study support the importance of early-pregnancy cardiovascular adaptation not only for healthy pregnancy outcomes but also as a marker of future cardiovascular health. 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,” wrote investigators.

This 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.