Sleep-disordered breathing in high-risk pregnancies is associated with elevated arterial stiffness and increased risk for preeclampsia

ABSTRACT Background Impaired vascular function is a central feature of pathologic processes preceding the onset of preeclampsia. To this end, arterial stiffness, a composite indicator of vascular health and an important vascular biomarker, has been found to be increased throughout pregnancy in those destined to develop preeclampsia and at the time of preeclampsia diagnosis. While sleep-disordered breathing in pregnancy has been associated with increased risk for preeclampsia, it is unknown if sleep-disordered breathing is associated with elevated arterial stiffness in pregnancy. Objectives This prospective observational cohort study aimed to evaluate arterial stiffness in pregnant women with and without sleep-disordered breathing and assess the interaction between arterial stiffness, sleep-disordered breathing, and preeclampsia risk. Study Design Women with high-risk singleton pregnancies were enrolled at 10-13 weeks’ gestation and completed the Epworth Sleepiness Score, Pittsburgh Sleep Quality Index, and Restless Legs Syndrome questionnaires each trimester. Sleep-disordered breathing was defined as loud snoring or witnessed apneas (≥3 times/week). Central arterial stiffness (carotid-femoral pulse wave velocity, the gold standard measure of arterial stiffness), peripheral arterial stiffness (carotid-radial pulse wave velocity), wave reflection (augmentation index, time to wave reflection), and hemodynamics (central blood pressures, pulse pressure amplification) were assessed non-invasively using applanation tonometry at recruitment and every four weeks from recruitment until delivery. Results High-risk pregnant women (n=181) were included in the study. Women with sleep-disordered breathing (n=41; 23%) had increased carotid-femoral pulse wave velocity across gestation independent of blood pressure, and body mass index (p=0.042). Differences observed in other vascular measures were not maintained after adjustment for confounders. Excessive daytime sleepiness, defined by Epworth Sleepiness Score >10, was associated with increased carotid-femoral pulse wave velocity only in women with sleep-disordered breathing (pinteraction=0.001). Mid-gestation (first or second trimester) sleep-disordered breathing was associated with a 3.4 odds ratio (0.9-12.9) for preeclampsia, which increased to 5.7 (1.1-26.0) in women with sleep-disordered breathing and hypersomnolence, while late (third trimester) sleep-disordered breathing was associated with a 8.2 odds ratio (1.5-39.5) for preeclampsia. Conclusions High-risk pregnant women with mid-gestational sleep-disordered breathing had greater arterial stiffness throughout gestation compared with those without. Sleep-disordered breathing at any time during pregnancy was also associated with increased preeclampsia risk, and this effect was amplified by hypersomnolence.