607: Severe blood pressure elevation and adverse outcomes in hypertensive disorders of pregnancy

Abstract

Severe blood pressure (BP) elevations in pregnancy predispose to adverse outcomes and require urgent treatment. Yet, when pregnant women present with a severe BP, treatment is often clouded by the underlying hypertensive diagnosis. We sought to evaluate the association between severe BP [systolic (SBP), diastolic (DBP), or both] and adverse outcomes, regardless of actual clinical diagnosis. Retrospective cohort study of deliveries ≥23 weeks’ gestation at a single institution (Oct ‘13 – Sept ‘18) with a hypertensive disorder of pregnancy. ICD discharge codes were used to identify subjects, followed by chart review. Subjects were categorized into four groups based on BP values before delivery: i) no severe BP; ii) severe SBP only (≥160 mmHg); iii) severe DBP only (≥110 mmHg); iv) both severe SBP and DBP. We assessed adverse neonatal and maternal outcomes in each group and performed multivariable logistic regression. Data were analyzed by ANOVA and chi-square test, with α=0.05. Among 11,825 deliveries, 1,630 (13.8%) had a hypertensive disorder of pregnancy. 698 (43.0%) subjects had a severe BP recording before delivery, with 346 (50.0%) having only severe SBP recordings, 88 (12.6%) having only severe DBP recordings, and 264 (39.0%) having both. Race, nulliparity, diabetes, and insurance were significantly different among BP groups. Adverse maternal and neonatal outcomes were greatest in those with both severe SBP and DBP, compared to other groups (Table 1). After adjusting for confounders, including other severe features of preeclampsia, the association between severe BP and adverse maternal outcomes was attenuated. However, the adverse neonatal outcomes remained significant for severe SBP and both severe SBP and DBP (aOR: 1.58, p=0.004 and aOR: 2.22, p< 0.001, respectively) (Table 2). In women with a hypertensive disorder of pregnancy, severe BPs are associated with adverse neonatal outcomes, independent of other severe features. Our data supports that severe BP elevation in pregnancy is a critical driver of adverse outcomes, regardless of the clinical diagnosis.View Large Image Figure ViewerDownload Hi-res image Download (PPT)