Maternal Sleep-Disordered Breathing in Pregnancy and Increased Nocturnal Glucose Levels in Women with Gestational Diabetes Mellitus.

BACKGROUND: Women with hyperglycemia during pregnancy are at high risk for adverse perinatal outcomes. Maternal sleep-disordered breathing (SDB) during pregnancy is common and is a risk factor for gestational diabetes mellitus (GDM). However, the relationship between SDB severity and glucose control is unknown. RESEARCH QUESTION: Is there an association between SDB severity and glucose levels as assessed by continuous glucose monitoring in GDM? STUDY DESIGN AND METHODS: Women with GDM underwent sleep recordings and 72-hour continuous glucose monitoring. Linear mixed models were used to estimate the association of the apnea-hypopnea index (AHI), rapid eye movement (REM)-AHI, and non-REM-AHI with mean glucose levels during nighttime (two periods: 11 pm to 3 am and 3 am to 6 am), daytime (8 am to 9 pm), and 24-hours. Models were adjusted for BMI and antihyperglycemic medications. RESULTS: In 65 participants who were 35 ± 5 (mean ± SD) years of age with BMI of 33 ± 7 kg/m2, 31% were undergoing insulin and/or metformin therapy. A ten-unit increase in AHI was associated with elevated nocturnal glucose levels (11 pm to 3 am: 0.20 mmol/L [95% CI, 0.04-0.40]) with persistent elevations into the morning (8 am: 0.26 mmol/L [95% CI, 0.08-0.4]) when adjusted for BMI and medications. REM-AHI was also associated with higher nocturnal and morning glucose levels, whereas non-REM was not. AHI was not associated with either mean daytime or 24-hour glucose levels. INTERPRETATION: Greater severity of SDB was associated with higher nocturnal and morning glucose levels in women with GDM.

A Pilot Randomized-Controlled Trial on the Effect of CPAP Treatment on Glycemic Control in Gestational Diabetes: Study Design and Methods.

Background: Gestational diabetes (GDM) is associated with adverse short- and long-term maternal and fetal outcomes. Observational data support a link between sleep-disordered breathing (SDB) during pregnancy and GDM. However, it is unknown whether treatment of SDB with continuous positive airway pressure (CPAP) improves glucose control in this patient population. In addition, CPAP adherence and feasibility as a treatment option in pregnancy is unknown. This pilot randomized, controlled trial aims to primarily determine the feasibility of CPAP treatment in pregnant women with SDB and GDM. This study is also investigating the effect of SDB treatment on 24-h glucose profiles as an exploratory outcome. Objectives: To describe the study methodology in this ongoing study of pregnant women with GDM and SDB. Patients and Methods: Pregnant women with GDM and SDB defined by apnea-hypopnea index (AHI) ≥10 (Chicago Scoring Criteria) on level 2 polysomnography are randomized to either auto titrating CPAP (experimental group) or a nasal dilator strip (control group) until delivery. The primary outcome, objectively-assessed adherence to CPAP, is measured over the course of the treatment period using device-specific software. Recruitment and retention rates will be calculated to assess the feasibility for planning future trials. Twenty-four hour glucose profiles are measured over a 72-h period using the continuous glucose monitoring (CGM) system, before and after the intervention. Conclusion: The results of this study will be highly informative to determine whether CPAP is a feasible treatment for pregnant women with GDM and SDB, a specialized population at risk for substantial comorbidity. The trial results will ultimately be useful in planning future SDB treatment trials in pregnancy and GDM. The study is registered on clinicaltrials.gov (NCT02245659).

Maternal sleep-disordered breathing and the risk of delivering small for gestational age infants: a prospective cohort study.

OBJECTIVE: It is unclear whether objectively measured maternal sleep-disordered breathing (SDB) leads to poor fetal outcomes. In this study, we prospectively assessed whether polysomnography-based diagnosis of SDB in the third trimester is associated with the delivery of small for gestational age (SGA) infants. STUDY DESIGN: Participants were recruited from a multicentre pregnancy cohort study. Eligible participants were evaluated for SDB based on symptoms (snoring and/or witnessed apnoeas assessed using the Pittsburgh Sleep Quality Index questionnaire) and in-home complete polysomnography in the third trimester. SGA was defined as <10th centile using customised birthweight centiles adjusted for maternal parity, prepregnancy body mass index (BMI), ethnicity, gestational age and infant sex. RESULTS: Of the 234 pregnant participants who completed a sleep study, 82% were Caucasian, with mean (SD) age of 31 (4.3) years and a prepregnancy BMI of 23 (4) kg/m(2). The delivery of SGA infants occurred in 27 (12%) of the study participants. The symptoms of SDB had poor overall sensitivity and specificity for diagnosing SDB identified by polysomnography. Symptoms of SDB in the third trimester demonstrated a potential association with delivering an SGA infant, however this did not reach statistical significance (OR 2.36 (95% CI 0.85 to 6.54, p=0.10)). However, the odds of delivering an SGA infant were significantly increased with polysomnography-based diagnosis of maternal SDB (using apnoea-hypopnoea index cut-off of 10, OR 2.65 (95% CI 1.15 to 6.10, p=0.02)). CONCLUSIONS: Objectively measured SDB in the third trimester is significantly associated with the delivery of SGA infants.