Sleep Apnea During Pregnancy Increases Risk of Preeclampsia and Arterial Stiffness

Impaired vascular function is a central feature of pathologic processes preceding the onset of preeclampsia. Studies have shown that sleep-disordered breathing in pregnancy has been associated with an increased risk for preeclampsia. However, it is unknown if sleep-disordered breathing is associated with elevated arterial stiffness in pregnancy. Therefore, Dr Stella S. Daskalopoulou and her team conducted a study 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.

It was a prospective observational cohort study in which the researchers included a total of 181 high-risk pregnant women at 10-13 weeks' gestation and completed the Epworth Sleepiness Score, Pittsburgh Sleep Quality Index, and Restless Legs Syndrome questionnaires each trimester. They determined sleep-disordered breathing as loud snoring or witnessed apneas (≥3 times/week). They assessed the following measures non-invasively using applanation tonometry at recruitment and every four weeks from recruitment until delivery.

◊ 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).

Key findings of the study:

• Upon analysis, the researchers found that 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.
• They determined excessive daytime sleepiness as Epworth Sleepiness Score >10. They found that excessive daytime sleepiness was associated with increased carotid-femoral pulse wave velocity only in women with sleep-disordered breathing.
• They found that women with mid-gestation (first or second trimester) SDB had an odds of 3.4 for preeclampsia, which increased to an odds of 5.7 for women who also experienced hypersomnolence.
• They also found that in women with late gestation (third trimester), sleep-disordered breathing was associated with an 8.2 odds ratio for preeclampsia.

The authors concluded, "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."

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DOI: https://doi.org/10.1016/j.ajog.2021.11.1366