In a recent article published in Hypertension, researchers investigated the long-term cardiac effects of de novo hypertensive disorders of pregnancy (HDP) in a cohort of 5,168 Hispanic/Latina women. These women residing in the United States, represent an ethnic minority group with a unique genetic architecture.
Study: Cardiac Abnormalities in Hispanic/Latina Women With Prior De Novo Hypertensive Disorders of Pregnancy. Image Credit: Ground Picture/Shutterstock.com
Previous studies have found several structural cardiac abnormalities and dysfunctions in pregnant women with HDP during the antepartum and immediate postpartum period.
Thus, ~20% of women with de novo HDP remain hypertensive six months post-postpartum and have between three to tenfold risk of developing chronic hypertension.
To date, studies investigating the effects of chronic hypertension on the development of cardiovascular disease (CVD) decades later have yielded mixed results. Thus, the cumulative effects of a history of HDP and chronic hypertension on cardiac abnormalities in women remain unclear.
About the study
The 16,415 participants recruited in the Hispanic Community Health Study/Study of Latinos (HCHS/SOL) multi-center study were women aged ≥45 years.
They underwent comprehensive two-dimensional transthoracic echocardiography (TTE) with image acquisition and measurements performed according to guidelines by trained sonographers and imaging specialists.
Participants who completed a transthoracic echocardiography (TTE) and their second visit between 2014 and 2017, and also reported at least one previous pregnancy during either this second visit or the baseline visit (conducted between 2008 and 2011), were comprehensively evaluated by the research team. This evaluation included an assessment of clinical and demographic characteristics, such as pregnancy history and preexisting comorbidities, and also involved measuring their blood pressure.
The researchers defined composite de novo HDP as any record of preeclampsia/eclampsia and gestational hypertension. They adhered to specific criteria and guidelines to define different types of left ventricular (LV) remodeling & hypertrophy and grading LV diastolic dysfunctions.
Next, the team used linear and logistic regression models to compare demographic, clinical, and echocardiographic traits in all participating women with and without prior HDP and examine their association with various cardiac structure and function measures.
These models adjusted for various covariates, such as age, study site, ethnicity, systolic BP, antihypertensive therapy, and body mass index (BMI), to name a few, but not multiple testing. They also analyzed different types of HDP, except eclampsia, given its small size was small.
In the mediation analysis, the researchers assessed potential interactions between current hypertension and HDP associations with echocardiographic traits, adjusting for age, study site, ethnic background, and current hypertension status. Finally, they weighted and adjusted for nonresponses.
The final sample for this analysis comprised 5,168 women. Among them, 724 (14%) had a history of de novo hypertensive disorders of pregnancy (HDP) during their pregnancies, while the remaining 4,444 women became pregnant but did not develop HDP. The average age of the women with HDP at the time of their echocardiogram (ECG) was 58.7 years.
In this study of Hispanic/Latina women, gestational hypertension emerged as the most prevalent type of HDP. Additionally, these women exhibited unique demographic and clinical characteristics, including a younger average age, higher levels of education, greater body mass index (BMI), and a history of dyslipidemia.
Moreover, a history of prior de novo HDP was linked to several cardiac issues. These included an increase in left ventricular relative wall thickness (LV RWT) and a higher risk of abnormal LV geometry. There was also a decrease in left ventricular ejection fraction (LVEF), with the respective coefficients (and 95% confidence intervals [CI]) being 0.09, 1.39, and -0.66.
In mediation analysis, the proportion of the correlation to LV EF and HDP mediated by current hypertension was moderate at 0.09 (95% CI). In contrast, the mediation effect of postpartum hypertension was higher for LV RWT, concentric LVH, and abnormal LV diastolic dysfunction, with respective coefficients of 0.28, 0.31, and 0.58 (95% CI).
By type of HDP, gestational hypertension was correlated to LV RWT and raised aberrant LV geometry risk across all models by ~1.8-fold, and preeclampsia showed no association with LV structure and function measure. However, women with an eclampsia history tended to have lower EF and LV stroke volume and higher LV RWT.
The study results showed that all women in this study cohort with prior HDP had detectable subclinical morphological and functional cardiac alterations, underscoring the importance of screening and management of hypertension in pregnant women.
Findings related to abnormal LV geometry, particularly LVH, are most clinically relevant. LVH is an established independent predictor of adverse cardiovascular events, including heart failure.
Researchers, thus, postulate that HDP may be a potentially novel sex-specific risk factor that explains the disproportionally higher risk of heart failure in women with a history of HDP.
However, the mechanisms by which HDP may lead to abnormalities in cardiac structure and function and whether they vary by race and ethnicity remain unclear and warrant further investigation.