A new systematic review and meta-analysis is shedding light on the impact gestational hypertension can have on future risk of cardiovascular diseases.
Clare Oliver-Williams, PhD
Results of a new systematic review and meta-analysis is shedding new light on the impact of gestational hypertension on the risk of future cardiovascular disease (CVD).
Findings from the study, which included data from more than 20 published articles and 3.5 million patients, indicated gestational hypertension during their first pregnancy increased a woman’s risk of overall CVD and coronary heart disease (CHD), but not thromboembolic events.
With inconsistencies between multiple studies examining the risk of cardiovascular disease for women with pregnancies complicated by gestational hypertension, investigators hoped to perform a comprehensive review of studies and data to assess these potential associations using data from PubMed, Embase, and Web of Science databases. Led by Clare Oliver-Williams, PhD, a research fellow at Cardiovascular Interdisciplinary Research Centre at the University of Cambridge, investigators designed their study as a systematic review and meta-analysis to assess the incidence of overall CVD, CHD, any stroke, heart failure, and thromboembolic events.
To be included in the study, published articles needed to compare the risk of at least 1 cardiovascular outcome for women with previous gestational hypertension versus women who had 1 or more normotensive pregnancy. For the purpose of the study, investigators defined gestational hypertension as a new onset of systolic and/or diastolic hypertension after 20 weeks of gestation without proteinuria.
Cardiovascular events occurring within the first year following pregnancy to avoid risk of comorbidities. Additional exclusion criteria included not having a cardiovascular outcome, combining gestational hypertension and preeclampsia, not having an independent exposure, and examining animals, men, children, or nulliparous women.
Of note, for inclusion in the meta-analysis at least 3 studies needed to evaluate the risk of the specific cardiovascular outcomes—files than 3 studies were found for an exposure-combination outcome it was included in the systematic review but not the study’s meta-analysis.
Using the aforementioned criteria and databases, 21 studies were included in the systematic review and 19 were included in the meta-analysis. Of the 21 included in the systematic review, 10 evaluated gestational hypertension during first pregnancy and 11 evaluated history of gestational hypertension. For the meta-analysis, 9 evaluated gestational hypertension in the first pregnancy and 10 evaluated history of gestational hypertension.
In total, the systematic review contained data from 3,601,192 women with 127913 a diagnosis of gestational hypertension. Upon analysis, gestational hypertension during first pregnancy was associated with a significantly greater risk of overall CVD (RR, 1.45; 95% CI, 1.17—1.80) and CHD (RR, 1.46; 95% CI, 1.23–1.73).
Investigators also pointed out results suggested gestational hypertension was associated with increased risk of stroke, but this increase did not reach statistical significance (RR, 1.26; 95% CI, 0.96-1.64). Conversely, the results of the analysis indicated gestational hypertension was not associated with an increased risk of thromboembolic events (RR, 0.88; 95% CI, 0.73-1.07).
When examining studies including women with a history of gestational hypertension in 1 or more pregnancies, results suggested increased risk reached statistical significance for incidence of CVD (RR, 1.81; 95% CI, 1.42—2.31), CHD (RR, 1.83; 95% CI, 1.33-2.51), and heart failure (RR, 1.77; 95% CI, 1.47-2.13).
Similarly to the previous analysis, gestational hypertension appeared to be associated with increased risk of stroke, but this increase did not reach statistical significance (RR, 1.50; 95% CI, 0.75-2.99). Investigators noted findings from 7 studies examining risk of MI, intracerebral hemorrhage, ischemic stroke, cardiomyopathy, and thromboembolic events were not included in the meta-analysis.
“This study adds to the literature on the relationship between women’s obstetric history and risk of cardiovascular events. A single previous review evaluated cardiovascular events after gestational hypertension; however, they focused on morbidity from CVD and cerebrovascular disease only. Our findings substantially build on it providing a comprehensive, holistic review of the risk,” investigators wrote.
This study, “Future Cardiovascular Disease Risk for Women With Gestational Hypertension: A Systematic Review and Meta-Analysis,” was published in the Journal of the American Heart Association.