Anthropometric Measures and Prediction of Maternal Sleep-Disordered Breathing

Abstract

Study Objectives: Pregnant women are at risk for sleep-disordered breathing (SDB); however, screening methods in this dynamic population are not well studied. The aim of this study was to examine whether anthropometric measures can accurately predict SDB in pregnant women. Methods: Pregnant women with snoring and overweight/obesity were recruited in the first trimester. Anthropometric measures were performed according to the International Standards for Anthropometric Assessment, including a seated neutral and extended neck Mallampati class. Home sleep apnea monitoring was performed using a level III device after completion of anthropometric assessment. SDB was defined as an apnea-hypopnea index ≥ 5 events/h of sleep. Pearson and Spearman tests examined correlations between various measures. Generalized linear models, sensitivity, specificity, and area under the curve as well as odds ratios were performed to test the model. Results: A total of 129 participants were recruited, and 23 had SDB. Average gestational age was 10.6 ± 1.9 weeks. Due to concerns over multicollinearity, the final model included extended Mallampati class and upright neck circumference. Neck circumference was significantly higher in participants with Mallampati classes 2/3 and grade 4 compared to participants with Mallampati class 1 (P = .0005). Increasing neck circumference was associated with higher odds of SDB (P = .0022). In Mallampati class 1, odds ratio for SDB was 2.89 (1.19, 7.03) per unit increase in neck circumference. Conclusions: Modeling neck circumference while allowing for differences by Mallampati class showed a nearly threefold increase in the risk of SDB with increasing neck circumference in women with Mallampati class 1. Other potential sites of airway obstruction need to be investigated in future research.

Sleep Pharmacotherapy for Common Sleep Disorders in Pregnancy and Lactation

“…115 Nonetheless, a recently completed trial investigating the impact of atomoxetine, a norepinephrine reuptake inhibitor, and oxybutynin, an antimuscarinic drug, on OSA showed dramatic improvements in the apnea-hypopnea index. 116 The relevance of the currently investigated drugs in the pregnant population is unclear because upper airway function, ventilatory control, and arousal physiology may all be different in this population due to the effect of significantly elevated levels of sex hormones 4 and other pregnancy-specific factors. Hence, there is a need to better understand pregnancy-specific physiology of upper airway and ventilatory control prior to attempting the use of pharmacotherapy in this population.…”

“…Hormonal shifts in pregnancy and lactation modify sleep architecture, 2,3 increase neuronal activity, affect respiratory drive, and control fluid distribution. 4 Anatomical and physiological factors such as ligament stretching, uterine contractions, or fetal movement result in sleep disruption and sleep fragmentation. 5 The respiratory system undergoes significant physiological changes that may influence breathing during sleep; namely, functional residual capacity is reduced in late pregnancy, with more pronounced reductions in the supine position.…”

Sleep-Disordered Breathing and Pregnancy-Related Cardiovascular Disease

“… 38 Another three-variable model—using BMI, age, and a measure of tongue enlargement—predicted polysomnography-verified SDB in the first and third trimesters with >85% accuracy. 39 Bourjeily et al 40 examined 100 women with self-reported snoring and BMI >30 during early pregnancy and found a model combining neck circumference and Mallampati classification (a score based on visual assessment of upper airway space) performed with >80% accuracy in identifying SDB.…”

Sleep position and breathing in late pregnancy and perinatal outcomes

“…We provided no information on neck circumference, which is a potential confounder in the relationship between lying in a supine position and disordered breathing during sleep. 26 Finally, the present cohort comprises a low-risk group of pregnant women. It is possible that sleep position may play a role in the association with adverse perinatal outcomes in higher-risk populations.…”

“…The study was approved by the institutional review board of the Tel Aviv Medical Center, and informed consent was obtained from all participants. Women with a singleton, uncomplicated pregnancy who attended a low-risk obstetric surveillance outpatient clinic were recruited at the end of their second trimester (gestational week [25][26][27] between November 2012 and June 2016. All participants completed a questionnaire on medical and obstetric history, smoking exposure history, and current pregnancy complications.…”