717 Shorter exposure to hypertensive disorders at delivery associated with progression to more severe disease

Abstract

Evidence supports delivery of non-severe hypertensive disorders of pregnancy at 37 weeks gestation. However, the clinical importance of disease duration at delivery is unclear. We explored whether the duration of exposure to gestational hypertension (gHTN) and preeclampsia without severe features (PEC) in term deliveries affects outcomes. This is a secondary analysis of an NIH-funded retrospective cohort study in which eligible patients delivered at a tertiary-care hospital from 01/2002 - 03/2013 with hypertensive disorders, diabetes and/or fetal growth restriction. For this analysis, patients delivering at 37+ weeks with a diagnosis of gHTN or PEC were included. Exposure duration was confirmed by trained research nurses. Our primary outcome was a maternal composite (progression to more severe hypertensive disorders, eclampsia, HELLP, pulmonary edema, ICU admission and mortality). Secondary outcomes included composite neonatal morbidity, progression to more severe hypertensive disorders, cesarean or assisted delivery, NICU admission, oligohydramnios and abruption. 3457 women met inclusion criteria. Patients were frequency matched by delivery GA (Table 1a,b). Shorter gHTN/PEC duration was associated with the maternal outcomes composite at all GAs [37’0-37’6, OR 2.2 (95% CI 1.5-3.4); 38’0-38’6, OR 5.8 (3.5-9.7); 39’0-39’6, OR 2.9 (1.9-4.5); 40’0+, OR 4.5 (2.2-9.0)] (Table 1a,b). Among secondary outcomes, shorter gHTN/PEC duration was associated with progression to more severe disease at all GAs [37’0-37’6, OR 2.5 (1.6-3.8); 38’0-38’6, OR 7.3 (4.1-12.9); 39’0-39’6, OR 4.0 (2.5-6.5); 40’0+, OR 18.2 (4.4-74.8)] (Table 1a,b). These associations persisted when duration of exposure was considered as a continuous variable. Shorter exposure to non-severe hypertensive disorders at time of delivery was associated with the maternal morbidity composite and progression to severe hypertensive disorders. This supports the clinical observation that some cases of pregnancy-induced hypertension are indolent, while others progress rapidly.View Large Image Figure ViewerDownload Hi-res image Download (PPT)