Vascular health years after a hypertensive disorder of pregnancy: The EPOCH study

Abstract

Background: Preeclampsia is associated with a two-fold increase in a woman's lifetime risk of developing atherosclerotic cardiovascular disease (ASCVD), but the reasons for this association are uncertain. The objective of this study was to examine the associations between vascular health and a hypertensive disorder of pregnancy among women ≥ 2 years postpartum.

Methods: Pre-menopausal women with a history of either a hypertensive disorder of pregnancy (cases: preeclampsia or gestational hypertension) or a normotensive pregnancy (controls) were enrolled. Participants were assessed for standard ASCVD risk factors and underwent vascular testing, including measurements of blood pressure, endothelial function, and carotid artery ultrasound. The primary outcomes were blood pressure, ASCVD risk, reactive hyperemia index measured by EndoPAT and carotid intima-medial thickness. The secondary outcomes were augmentation index normalized to 75 beats per minute and pulse wave amplitude measured by EndoPAT, and carotid elastic modulus and carotid beta-stiffness measured by carotid ultrasound.

Results: Participants had a mean age of 40.7 years and were 5.7 years since their last pregnancy. In bivariate analyses, cases (N = 68) were more likely than controls (N = 71) to have hypertension (18% vs 4%, P = .034), higher calculated ASCVD risk (0.6 vs 0.4, P = .02), higher blood pressures (systolic: 118.5 vs 111.6 mm Hg, P = .0004; diastolic: 75.2 vs 69.8 mm Hg, P = .0004), and higher augmentation index values (7.7 vs 2.3, P = .03). They did not, however, differ significantly in carotid intima-media thickness (0.5 vs 0.5, P = .29) or reactive hyperemia index (2.1 vs 2.1, P = .93), nor in pulse wave amplitude (416 vs 326, P = .11), carotid elastic modulus (445 vs 426, P = .36), or carotid beta stiffness (2.8 vs 2.8, P = .86).

Conclusion: Women with a prior hypertensive disorder of pregnancy had higher ASCVD risk and blood pressures several years postpartum, but did not have more endothelial dysfunction or subclinical atherosclerosis.

Figure 1.

Study flow diagram

Figure 2.

Box-and-whisker plots of outcome measures (vertical axis) in cases (left) and controls (right). The top of the box is the 75^th percentile, the line in the middle of the box is the 50^th percentile, and the bottom of the box is the 25^th percentile. The low and high whiskers indicate the most extreme point that is less than or equal to 1.5 times the 25^th or 75^th percentile, respectively. Red points represent data from cases with preeclampsia with severe features, blue points represent data from cases who did not have preeclampsia with severe features, and the black dots represent control subjects. Abbreviations: PE w/SF = preeclampsia with severe features; PE = preeclampsia without severe features; GHTN = gestational hypertension; CTL: control.

Figure 3.

Plots of outcome measures (vertical axis) versus participant age (left panels) and mean systolic blood pressure (right panels). In the left panels, red circles indicate cases and black squares indicate controls; in the right panels, filled circles and squares represent participants not taking an antihypertensive medication, and empty circles and squares represent participants who had taken an antihypertensive medication within 48 hours of the study visit. Simple linear regression lines were fitted separately to the data from cases and controls, and drawn in red for cases and in black for controls. Abbreviations: HTN med = antihypertensive medication