Epidemiology and Mechanisms of De Novo and Persistent Hypertension in the Postpartum Period

Abstract

Background The pathophysiology of hypertension in the immediate postpartum period is unclear. Methods and Results We studied 988 consecutive women admitted to a tertiary medical center for cesarean section of a singleton pregnancy. Angiogenic factors, soluble fms-like tyrosine kinase 1 (sFlt1) and placental growth factor (PlGF), both biomarkers associated with preeclampsia, were measured on antepartum blood samples. We then performed multivariable analyses to determine factors associated with the risk of developing postpartum hypertension. Of the 988 women, 184 women (18.6%) developed postpartum hypertension. 77 out of 184 women developed de novo hypertension in the postpartum period and the remainder had a hypertensive disorder of pregnancy in the antepartum period. A higher body mass index and history of diabetes mellitus were associated with development of postpartum hypertension. The antepartum sFlt1/PlGF ratio positively correlated with blood pressures in the postpartum period [highest postpartum systolic (r=0.29; P<0.001) and diastolic (r=0.28, P<0.001)]. Moreover, the highest tertile of the antepartum sFlt1/PlGF ratio was independently associated with postpartum hypertension [OR: 2.25 (1.19, 4.25), P=0.01 in the de novo hypertensive group and 2.61 (1.12, 6.05) in the persistent hypertensive group; P=0.02] in multivariable analysis. Women developing postpartum hypertension had longer hospitalization than those who remained normotensive (6.5 ± 3.5 versus 5.7 ± 3.4 days; P<0.001). Conclusions Hypertension in the postpartum period is relatively common and is associated with prolonged hospitalization. Women with postpartum hypertension share similar clinical risk factors as well as a similar antepartum plasma angiogenic profile found in women with preeclampsia. These data suggest that postpartum hypertension may represent a group of women with subclinical or unresolved preeclampsia.

Postpartum Hypertension

“…In the current issue of Circulation, Goel and colleagues 4 extend our knowledge of the epidemiology and mechanisms of postpartum hypertension and report a high incidence (18.6%) in 988 consecutive women admitted to a tertiary medical center for cesarean delivery. They also report that the antepartum levels of angiogenic factors known to be relevant to the pathophysiology of preeclampsia, 5 soluble fms-like tyrosine kinase 1 (sFlt1) and placental growth factor (PlGF), and the ratio of sFlt1/PlGF, as well, were more likely to be abnormal in women who developed postpartum hypertension than in those who did not.…”

“…7 The most recent American College of Obstetricians and Gynecologists guidelines 8 recommends abandoning the older designation transient hypertension (hypertension diagnosed after 20 weeks gestation, without other laboratory signs of preeclampsia or systemic organ dysfunction), 9 in favor of the term gestational hypertension. In the Goel article, 4 both categories (transient and gestational hypertension) are reported, and the majority of subjects were actually diagnosed with transient hypertension. The clinical characteristics of this group are not presented; thus, one wonders whether these women represented a heterogeneous group of disorders: eg, gestational hypertension and preeclampsia without proteinuria.…”

“…Although it is reported that women with gestational hypertension have lower maternal morbidity, including cerebrovascular disorders and mortality, than eclampsia/preeclampsia, 10 it is well recognized that some (10%-25%) will develop preeclampsia before delivery. The uncertainties in the diagnostic categories in the Goel study 4 preclude making conclusions regarding the association of diagnostic category with risk of PP HTN. However, one could argue that postpartum, the level of BP, rather than the diagnostic category, is more relevant, because fetal well-being is no longer a concern, and the prevention of maternal cerebrovascular and cardiovascular events is the goal of treatment.…”

“…Goel and colleagues 4 have made an important contribution by highlighting the relatively high incidence of postpartum hypertension. Until now, the focus of pregnancy-associated hypertension research has been on antepartum hypertension, with only a few studies and reviews addressing the postpartum period.…”

“…In the United Kingdom, between 2006 and 2008, the majority of the maternal deaths from severe preeclampsia and eclampsia were related to either intracranial hemorrhage or eclampsia. 14 The observation by Goel et al 4 that abnormalities in angiogenic factors are associated with postpartum hypertension suggests that women with pathophysiologic features of preeclampsia are especially at risk, because these biomarkers have been shown to reliably distinguish preeclampsia from other forms of hypertensive disorders in pregnancy. In their study, antepartum sFlt1 levels were higher and PlGF levels were lower in women with postpartum hypertension than in women who were normotensive postpartum.…”