Positive Airway Pressure Treatment of Obstructive Sleep-disordered Breathing in Hypertensive Disorders of Pregnancy

Effects of Positive Airway Pressure Treatment of Obstructive Sleep-disordered Breathing on Maternal and Fetal Outcomes in Hypertensive Disorders of Pregnancy: a Pilot Randomized Controlled Trial

The purpose of this study is to conduct a pilot randomized, controlled trial to evaluate the feasibility and obtain pilot outcome data for a subsequent definitive trial evaluating the effects of postitive airway pressure (PAP) treatment of obstructive sleep-disordered breathing (OSDB) on blood pressure control and maternal and fetal outcomes in hypertensive disorders of pregnancy. The primary aim of the pilot study is to assess feasibility measured as the rates of subject recruitment, adequate (>4h/night) PAP adherence (primary outcome measure) and protocol completion. Secondary aims will be to obtain preliminary data on the effects of PAP on maternal blood pressure, complications of hypertension, arterial stiffness and vascular biomarkers, course of labor and delivery and fetal outcomes including growth restriction, prematurity, and neonatal distress.

Inclusion Criteria:

• ≥ 18 y with a singleton pregnancy, ≥ 12 weeks' gestation
• diagnosis of hypertensive disorder of pregnancy, including pre-existing hypertension, gestational hypertension and pre-eclampsia, as defined by Canadian Hypertensive Disorders of Pregnancy Working Group Criteria (Magee et al; Best Practice and Research Clinical obstetrics & Gynaecology. 2015;29(5):643-657)
• presence of obstructive sleep-disordered breathing (OSDB) on a single night in-home complete (Level 2) polysomnogram defined by an apnea-hypopnea index (AHI) ≥ 5 events/h and/or the presence of inspiratory flow limitation on ≥ 30% of breaths.

Exclusion Criteria:

• severe pre-eclampsia/eclampsia requiring urgent delivery
• chronic kidney disease or other secondary cause of hypertension
• known cardiac disease, transient ischemic attack/stroke
• malignancy or other chronic medical or psychiatric condition
• smoking, alcohol use, illicit drugs
• current/recent treatment for sleep-disordered breathing
• severe sleep-disordered breathing defined as an apnea-hypopnea index (AHI) ≥ 30/h with either severe sleepiness (Epworth sleepiness score ≥ 15) or hypoxemia (4% Oxygen Desaturation Index ≥30/h or arterial oxygen saturation (SpO2) <80% for >10% of Total Sleep Time)