Early developmental outcome in children born to mothers with obstructive sleep apnea

Effect of Obstructive Sleep Apnea during Pregnancy on Fetal Development: Gene Expression Profile of Cord Blood

Obstructive sleep apnea (OSA) is quite prevalent during pregnancy and is associated with adverse perinatal outcomes, but its potential influence on fetal development remains unclear. This study investigated maternal OSA impact on the fetus by analyzing gene expression profiles in whole cord blood (WCB). Ten women in the third trimester of pregnancy were included, five OSA and five non-OSA cases. WCB RNA expression was analyzed by microarray technology to identify differentially expressed genes (DEGs) under OSA conditions. After data normalization, 3238 genes showed significant differential expression under OSA conditions, with 2690 upregulated genes and 548 downregulated genes. Functional enrichment was conducted using gene set enrichment analysis (GSEA) applied to Gene Ontology annotations. Key biological processes involved in OSA were identified, including response to oxidative stress and hypoxia, apoptosis, insulin response and secretion, and placental development. Moreover, DEGs were confirmed through qPCR analyses in additional WCB samples (7 with OSA and 13 without OSA). This highlighted differential expression of several genes in OSA (EGR1, PFN1 and PRKAR1A), with distinct gene expression profiles observed during rapid eye movement (REM)-OSA in pregnancy (PFN1, UBA52, EGR1, STX4, MYC, JUNB, and MAPKAP). These findings suggest that OSA, particularly during REM sleep, may negatively impact various biological processes during fetal development.

Referral practices and treatment of obstructive sleep apnea in pregnancies with obesity

Objective

Obstructive sleep apnea (OSA) affects maternal and neonatal health during pregnancy. This study aimed to identify characteristics and comorbidities associated with sleep clinic referral in high-risk pregnancies with Body Mass Index (BMI) ≥35 kg/m2.

Method

Retrospective cohort study for individuals in a high-risk pregnancy clinic at a tertiary Australian hospital from 1 January to 31 December 2020 with BMI≥35 kg/m2. The primary outcome measure was sleep clinic referral. Exposure data included multiple comorbidities and formal tools (Epworth Sleepiness Scale and STOP-BANG). Multivariable analysis was used to identify factors associated with referral. Descriptive data on barriers to diagnosis and treatment were collected.

Results

Of 161 pregnant individuals, 38.5% were screened using formal tools and 13.7% were referred to sleep clinic. Having STOP-BANG performed was associated with sleep clinic referral (Odds Ratio: 18.04, 95% Confidence Interval:4.5-71.7, p < 0.001). No clinical characteristics were associated with the likelihood of performing STOP-BANG. The COVID-19 pandemic was a treatment barrier for three individuals.

Conclusions

Current screening practices identify pregnant individuals with the highest pre-test probability of having OSA. Future research should evaluate real-world strategies to improve identification and management in this high-risk population.

Home monitoring for clinically suspected obstructive sleep apnea in pregnancy

STUDY OBJECTIVES

To determine if a home sleep apnea test (HSAT) using a type III portable monitor (PM), Nox-T3 (Nox Medical, Inc., Reykjavik, Iceland), detects obstructive sleep apnea in pregnant women.

METHODS

Ninety-two pregnant women (34.5 ± 4.3 years; gestational age 25.4 ± 8.9 weeks; body mass index 29.9 ± 4.7 kg/m2) with suspected obstructive sleep apnea underwent HSAT with the Nox-T3 PM followed by overnight polysomnography (PSG) and PM recording simultaneously in the laboratory within 1 week. PMs were scored automatically and manually using a 3% criteria and compared with PSGs scored by following guidelines.

RESULTS

Apnea-hypopnea indexes were 8.56 ± 10.42, 8.19 ± 13.79, and 8.71 ± 14.19 events/h on HSAT, in-laboratory PM recording, and PSG (P = .955), respectively. Bland-Altman analysis of the apnea-hypopnea index on PSG vs HSAT showed a mean difference (95% confidence interval) of -0.15 (-1.83, 1.53); limits of agreement (± 2 SD) were -16.26 to 16.56 events/h. Based on a threshold apnea-hypopnea index ≥ 5 events/h, HSAT had 91% sensitivity, 85% specificity, 84% positive-predictive value, and 92% negative-predictive value compared with PSG. When comparing the simultaneous recordings, closer agreement was observed. Automated vs manual analysis of PM showed no significant difference.

CONCLUSIONS

A type III PM had an acceptable failure rate and high diagnostic performance operating as a reasonable alternative for in-laboratory PSG in pregnant women.

CITATION

Wang J, Zhang C, Xu L, et al. Home monitoring for clinically suspected obstructive sleep apnea in pregnancy. J Clin Sleep Med. 2023;19(11):1951-1960.

Fetal heart rate responses to maternal sleep-disordered breathing

BACKGROUND

Maternal sleep-disordered breathing is associated with adverse pregnancy outcomes and is considered to be deleterious to the developing fetus. Maternal obesity potentiates sleep-disordered breathing, which, in turn, may contribute to the effect of maternal obesity on adverse fetal outcomes. However, only a few empirical studies have evaluated the contemporaneous effects of maternal sleep-disordered breathing events on fetal well-being. These events include apnea and hypopnea with accompanying desaturations in oxyhemoglobin.

OBJECTIVE

This study aimed to reconcile contradictory findings on the associations between maternal apnea or hypopnea events and clinical indicators of fetal compromise. It also sought to broaden the knowledge base by examining the fetal heart rate and heart rate variability before, during, and after episodes of maternal apnea or hypopnea. To accomplish this, we employed overnight polysomnography, the gold standard for ascertaining maternal sleep-disordered breathing, and synchronized it with continuous fetal electrocardiography.

STUDY DESIGN

A total of 84 pregnant women with obesity (body mass index >30 kg/m2) participated in laboratory-based polysomnography with digitized fetal electrocardiography recordings during or near 36 weeks of gestation. Sleep was recorded, on average, for 7 hours. Decelerations in fetal heart rate were identified. Fetal heart rate and heart rate variability were quantified before, during, and after each apnea or hypopnea event. Event-level intensity (desaturation magnitude, duration, and nadir O2 saturation level) and person-level characteristics based on the full overnight recording (apnea-hypopnea index, mean O2 saturation, and O2 saturation variability) were analyzed as potential moderators using linear mixed effects models.

RESULTS

A total of 2936 sleep-disordered breathing events were identified, distributed among all but 2 participants. On average, participants exhibited 8.7 episodes of apnea or hypopnea per hour (mean desaturation duration, 19.1 seconds; mean O2 saturation nadir, 86.6% per episode); nearly half (n=39) of the participants met the criteria for obstructive sleep apnea. Only 45 of 2936 apnea or hypopnea events were followed by decelerations (1.5%). Conversely, most (n=333, 88%) of the 378 observed decelerations, including the prolonged ones, did not follow an apnea or a hypopnea event. Maternal sleep-disordered breathing burden, body mass index, and fetal sex were unrelated to the number of decelerations. Fetal heart rate variability increased during events of maternal apnea or hypopnea but returned to initial levels soon thereafter. There was a dose-response association between the size of the increase in fetal heart rate variability and the maternal apnea-hypopnea index, event duration, and desaturation depth. Longer desaturations were associated with a decreased likelihood of the variability returning to baseline levels after the event. The mean fetal heart rate did not change during episodes of maternal apnea or hypopnea.

CONCLUSION

Episodes of maternal sleep apnea and hypopnea did not evoke decelerations in the fetal heart rate despite the predisposing risk factors that accompany maternal obesity. The significance of the modest transitory increase in fetal heart rate variability in response to apnea and hypopnea episodes is not clear but may reflect compensatory, delimited autonomic responses to momentarily adverse conditions. This study found no evidence that episodes of maternal sleep-disordered breathing pose an immediate threat, as reflected in fetal heart rate responses, to the near-term fetus.

Adverse effects of inadequate sleep duration patterns during pregnancy on toddlers suspected developmental delay: A longitudinal study

BACKGROUND

Although studies have reported the effects of inadequate sleep on maternal health, few have examined the relationships of maternal sleep patterns with fetal health and early childhood development. This study investigated maternal sleep duration patterns from early pregnancy to 3-years postpartum and their effects on birth outcomes and child development.

METHODS

This study recruited pregnant women and their partners during prenatal visits at five selected hospitals in the Taipei area; follow-up lasted from July 2011 to April 2021. A total of 1178 parents completed self-reported assessments from early pregnancy until childbirth and 544 completed eight assessments up to 3-years postpartum. Generalized estimated equation models were used for analyses.

RESULTS

Group-based trajectory modeling was used to identify four trajectories of sleep duration patterns. Although maternal sleep duration was not associated with birth outcomes, maternal "short decreasing" and "stably short" sleep patterns were associated with a higher risk of suspected overall developmental delay and language developmental delay, respectively. Furthermore, an "extremely long decreasing" pattern was associated with a higher risk of suspected overall developmental delay, [adjusted odds ratio (aOR) = 2.97, 95% confidence interval (CI):1.39-6.36)], gross motor delay, (aOR = 3.14, 95% CI: 1.42-6.99) and language developmental delay (aOR = 4.59, 95% CI:1.62-13.00). The results were significant for the children of multiparous women.

CONCLUSIONS

We identified a U-shaped distribution of risk between offspring developmental delay and maternal prenatal sleep duration, with the highest risk levels on both ends of the maternal prenatal sleep duration pattern. Interventions for maternal sleep are relatively straightforward to implement and should thus be a key part of standard prenatal care.

Obstructive sleep apnea in pregnant women

The prevalence of OSA in the low-risk obstetric population is thought to be low; best estimates have been extrapolated from the one available large prospective study and likely range between 3–8%.1 OSA prevalence in high-risk pregnant women such as those with obesity and chronic hypertension is significantly higher as extrapolated from several smaller prospective studies which have reported a prevalence as high as 37% in obese women.2 –6 Despite the high prevalence of OSA in high-risk pregnant women, it remains underdiagnosed due to several factors.

An emerging body of literature suggests that OSA may also have serious implications for the health of mothers and fetuses during and beyond pregnancy, but there is still no data to determine if OSA treatment mitigates these adverse outcomes. In this review, we will examine this body of literature from the perspective of the anesthesiologist: the association between pregnancy and the development or worsening of OSA; OSA as it relates to adverse maternal and fetal outcomes; antepartum and screening considerations for OSA in pregnant women; and recommendations regarding the peripartum management of OSA.