Effect of CPAP Treatment on Glycemic Control in Gestational Diabetes: A Pilot Randomized-Controlled Trial

Gestational diabetes (GDM), defined as glucose intolerance that is first recognized during pregnancy, is associated with adverse maternal and fetal outcomes. Sleep-disordered breathing (SDB) is characterized by breathing pauses during sleep leading to recurrent arousals and intermittent hypoxia. The resulting increases in sympathetic drive, cortisol and inflammation have been shown to lead to glucose dysregulation. In that SDB is prevalent during pregnancy, SDB may represent a novel risk factor for GDM, as suggested by recent observational studies. No interventional studies evaluating the effects of SDB treatment on GDM outcomes have yet been published.

General Objective: To perform a pilot study to assess the feasibility of conducting a randomized-controlled trial using continuous positive airway pressure (CPAP) to evaluate the effects of SDB treatment on maternal-fetal outcomes in GDM.

Primary Aim of Pilot Study: 1) To assess CPAP adherence in pregnant patients with GDM. Secondary Aims: 2) To assess recruitment and retention rates over ~2 months of treatment 3) To assess adequacy of nasal dilator strips as the control intervention 4) To measure maternal glucose levels to determine sample size calculations for a future large-scale multi-site randomized-controlled trial.

Inclusion criteria

• Pregnant women aged ≥ 18 y referred to the GDM clinic at the McGill University Health Centre
• >20 weeks and <34 weeks gestational age at time of recruitment
• Gestational diabetes
• Sleep-disordered breathing (SDB)

Exclusion criteria

• Pre-gestational type 1 or type 2 diabetes
• Multiple pregnancy
• Conception by IVF
• Prior treatment for SDB
• severe medical illness
• Severe SDB (AHI >30) and Epworth Sleepiness Scale >15 or oxygen desaturation index >30 or sustained hypoxia < 80%
• Habitual sleep duration on average less than 5 hours/night (determined by actigraphy)
• Cigarette smoking, alcohol consumption or illicit drug use