Grant: Travel Awards - Institute Community Support

Rationale: Sleep-disordered breathing (SDB) increases in prevalence over the course of pregnancy and occurs in ~30% of women by the third trimester. Maternal SDB is associated with an increased risk of developing gestational diabetes (GDM). However, the relationship between maternal SDB and glucose levels is unknown. Continuous glucose monitoring (CGM) is an emerging technique for continuous glucose data collection over several days. Our objective was to determine if there are time-dependent changes in glucose levels from CGM data in relation to severity of maternal SDB. Methods: Women with GDM underwent at-home level 2 sleep recordings for assessment of SDB and continuous 72-hour glucose level measurements using CGM (iPro2, MedTronic). After subcutaneous insertion, interstitial glucose measurements occurred every five minutes across 72-hours consecutively. Accuracy validation occurred daily with 3-4 capillary blood glucose measurements. Glucose results were blinded from participants. Results: Sixty-eight pregnant participants with GDM underwent sleep recordings with the following characteristics (mean SD): 35±4.1 years of age, BMI of 32±7 kg/m2, 29±3.6 weeks gestational age at enrolment, and 33% on insulin/metformin. The mean AHI was 17.1±10.9 while the mean oxygen desaturation index (ODI) was 3.3±5.1. Increasing AHI was significantly associated with elevated nocturnal glucose levels between 11pm-3am (p=0.02) and 3am-6am (p=0.01), but not mean 24-hour glucose (p=0.1), even after adjustment for age, BMI and use of insulin/metformin. Conclusion: Increasing AHI is associated with nocturnal glucose levels (11pm-6am), even after adjustment for all confounders. Without treatment, SDB may be a risk factor for the development of GDM and/or poor glucose control in pregnancy. Interventional studies aimed at treating SDB in pregnancy are needed to further determine the causal relationship between maternal SDB and glucose control in GDM.