Evaluating the maternal and perinatal sequelae of severe gestational hypertension

Abstract

Background: Hypertensive disorders of pregnancy are widespread and have long-standing implications for women's health. Historically, the management of "severe gestational hypertension," or the presence of severely elevated blood pressures without any other signs or symptoms of end-organ damage meeting the criteria for preeclampsia, has been unclear. The new American College of Obstetricians and Gynecologists guidelines based on expert opinion recommend that severe gestational hypertension be treated similarly to preeclampsia with severe features, but data regarding outcomes for women with this diagnosis have been limited.

Objective: This study aimed to compare the maternal and perinatal sequelae of severe gestational hypertension with that of other types of hypertensive disorders of pregnancy.

Study design: This is a retrospective cohort study of women with hypertensive disease of pregnancy who delivered at a single tertiary care center between February and December 2018. Women with chronic hypertension; hemolysis, elevated liver enzymes, and low platelet count syndrome; preexisting kidney, liver, rheumatologic, or hematologic disorders; or multifetal pregnancies were excluded. Women were categorized as having severe gestational hypertension if they had a sustained systolic blood pressure of >160 mm Hg or a diastolic blood pressure of >110 mm Hg without other criteria for preeclampsia. The primary comparison was between women with severe gestational hypertension and women with preeclampsia without severe features. Secondary comparisons included women with severe gestational hypertension vs women with other types of hypertensive disease of pregnancy. The primary outcome for this analysis was small-for-gestational-age birth. We also evaluated other maternal and neonatal morbidities including but not limited to pulmonary embolism, stroke, eclampsia, blood transfusion, mechanical ventilation, intensive care unit admission, death, 5-minute Apgar score of ≤4, umbilical cord pH, neonatal intensive care unit admission of >2 days, respiratory distress syndrome, and neonatal death. Bivariate analyses using chi-square tests and logistic regressions adjusting for race, ethnicity, age, body mass index, parity, and insurance status were performed to compare frequencies of outcomes for each type of hypertensive disease of pregnancy with those of severe gestational hypertension.

Results: Of 2076 women eligible for inclusion, 12.2% (n=254) had severe gestational hypertension and 379 (18.2%) had preeclampsia without severe features. Although there was no difference in the odds of small-for-gestational-age birth between women with severe gestational hypertension and women with preeclampsia without severe features (14.7% vs 9.8%; adjusted odds ratio, 0.72; 95% confidence interval, 0.44-1.21), the latter were significantly less likely to receive a prescription for antihypertensive medication at discharge (OR 0.11, 95% CI 0.06-0.22) or to be readmitted postpartum (OR 0.14, 95% CI 0.04-0.50).

Conclusion: There was no difference in the primary outcome, that is, rate of small-for-gestational-age birth, between women with severe gestational hypertension and women with preeclampsia without severe features. However, women with severe gestational hypertension had greater odds of other maternal and neonatal morbidities than women with preeclampsia without severe features or mild gestational hypertension. These findings support recent recommendations regarding the management of women with severe gestational hypertension.

Keywords: hypertensive disease of pregnancy; maternal morbidity; postpartum readmissions.