Increased plasma levels of inflammatory markers and upper airway resistance during sleep in pre-eclampsia☆☆☆

Abstract 

Objectives

To evaluate pregnancy-associated sleep disorders, pregnancy outcomes and inflammatory markers in pre-eclampsia and normal pregnancy (control).

Patients and methods

We studied 15 consecutive pre-eclamptic women and 14 controls. Pre-eclamptic women underwent overnight pulse oximetry and nasal pressure measurements at a university teaching hospital, and the sleep study for the controls was performed at home. Mean gestation was 31 weeks. Nasal airflow was carefully analyzed visually, and the time with flow limitation was calculated as a percentage of total recording time. At the time of the sleep study, the subjects were clinically evaluated, they answered sleep questionnaires, and fasting blood samples were drawn for tumor necrosis factor alpha TNF-α, interleukin 6 (IL-6) and sensitive C-reactive protein. Pregnancy outcomes were collected after delivery.

Results

Pre-eclampsia patients spent significantly more time with flow limitation (mean±SD: 21±18% vs. 4±9%), had higher plasma levels of TNF-α (6.2±2.3ng/l vs. 4.1±ng/l) and IL-6 (4.4±ng/l vs. 1.2±0.4ng/l), had more generalized edema, had increased fatigue and snoring, and had poorer pregnancy outcomes than did controls. Age, gestational age, mean SpO₂ and body mass index did not differ between the groups.

Conclusions

Pregnant women with pre-eclampsia showed significantly more nasal flow limitation during the night, higher fasting IL-6 and TNF-α plasma levels, more edema and worse pregnancy outcomes than did healthy pregnant women.

Keywords: Pre-eclampsia, Pregnancy, Upper airway resistance, Snoring, Tumor necrosis factor alpha, Interleukin 6