Sleep Disordered Breathing and Gestational Hypertension: Postpartum Follow-up Study

Abstract

Gestational hypertension (GH) is a newly recognized risk factor for adverse cardiovascular events later in life. Sleep disordered breathing (SDB) is an established risk factor for adverse cardiovascular events. Recent research has suggested that women with GH may have an increased rate of SDB during pregnancy, but it is not known if this higher rate of SDB persists into the postpartum state. To assess whether women with GH continue to have an increased rate of SDB compared to healthy pregnant women, after the physiologic changes of pregnancy resolve. We previously studied women with GH and uncomplicated pregnancies with sleep questionnaires and level 1 polysomnography. Participants were invited to participate in repeat testing 1-2 years postpartum. Respiratory disturbance index (RDI) differences were assessed. Eighteen subjects (11 GH and 7 healthy) had complete follow-up data available for comparison with antepartum data. This group was representative of the initial antepartum cohort. Women with GH experienced a decrease in mean RDI from antepartum to postpartum (12.0 ± 12.3 vs. 2.9 ± 2.9; P = 0.02). Healthy women did not experience the same change (2.8 ± 5.3 vs. 2.1 ± 3.2; P = 0.81). Postpartum comparisons showed the mean RDI of women with GH had decreased to be similar to that of healthy women (P = 0.75). SDB in women with gestational hypertension improved in the postpartum state to levels indistinguishable from our healthy subjects. This suggests that the physiologic effects of pregnancy may have had a pathologic role in the development of antepartum SDB in women with GH.