Lateral wall collapse from sleep endoscopy and airflow shape predicts hypoglossal nerve stimulation efficacy in obstructive sleep apnea.

Rationale: Patient selection for hypoglossal nerve stimulation (HGNS) for obstructive sleep apnea (OSA) requires assessment of pharyngeal site of collapse using drug-induced sleep endoscopy (DISE).

Objectives: The current study aims to address two key knowledge gaps: First, we prospectively confirm that, among HGNS candidates, reduced HGNS efficacy is associated with oropharyngeal lateral wall (OLW) collapse (Aim 1). Second, given DISE is resource-intensive procedure and delays treatment, we evaluate whether a recently-developed non-invasive method for identifying OLW collapse using airflow shapes is associated with reduced HGNS efficacy (Aim 2).

Atomoxetine plus oxybutynin for symptomatic snoring and airflow limitation in individuals without moderate-to-severe obstructive sleep apnea.

Study Objectives: Sleep-disordered breathing is incompletely characterized by the apnea-hypopnea index. Although typically viewed as milder disease, snoring and flow limitation can yield major deficits in sleep health for both patients and their bed partners. Here we tested whether a combined noradrenergic and antimuscarinic intervention to activate pharyngeal muscles yields improved snoring loudness and flow limitation severity, plus self-reported outcomes, by snorers and their bed partners.

Site of Collapse during Drug-induced Sleep Endoscopy Is Associated with Polysomnographic Endotypic Traits.

Rationale: Both the site of upper airway collapse during drug-induced sleep endoscopy (DISE) and pathophysiological endotypic traits are associated with non-CPAP treatment outcomes for obstructive sleep apnea (OSA). Reduced hypoglossal nerve stimulation (HGNS) treatment efficacy has been associated with complete concentric collapse at the level of the palate (CCCp), lateral wall collapse, lower arousal threshold, and poor dilator muscle compensation. However, these predictors may not be independent.

The effect of M-current activation on controller gain and obstructive sleep apnoea severity: a randomised controlled trial using flupirtine.

Ventilatory control instability, or high loop gain (LG), contributes towards upper airway collapse in approximately one-third of people with obstructive sleep apnoea (OSA). A high LG can be the product of elevated chemosensitivity (controller gain) and/or an excessive ventilatory output (plant gain). Therapies such as carbonic anhydrase inhibitors (targeting plant gain) have been shown to reduce OSA severity; however, there is a lack of viable pharmacological options targeting controller gain.

Sleep Apnea Specific Hypoxic Burden in Children With Down Syndrome and Typically Developing Children.

Hypoxic burden (HB) is a measure incorporating frequency, depth and duration of respiratory event-related desaturations. While HB is associated with cardiovascular disease in adults with obstructive sleep apnea (OSA), it has not been assessed in typically developing (TD) children with OSA, nor in children with Down syndrome (DS), who have a higher incidence of OSA with more severe hypoxia. We assessed whether HB in these children was related to heart rate variability (HRV), an indicator of cardiovascular outcomes.

Ventilatory Burden Predicts Change in Sleepiness Following Positive Airway Pressure in Sleep Apnea.

Rationale: Excessive daytime sleepiness, an important symptom of obstructive sleep apnea (OSA), is commonly quantified using the Epworth Sleepiness Scale score (ESS). Baseline OSA severity measures (ventilatory burden, flow limitation, and hypoxemia) provide insights into OSA pathophysiology and could predict changes in sleepiness (i.e.

Sleep deprivation and recovery: Endurance racing as a novel model.

The aim of this study was to investigate sleep-wake behavior and gain insights into perceived impairment (sleep, fatigue, and cognitive function) of athletes competing in two international multi-day adventure races. Twenty-four athletes took part across two independent adventure races: Queensland, Australia and Alaska, USA. Individual sleep periods were determined via actigraphy, and racers self-reported their perceived sleep disturbances, sleep impairment, fatigue and cognitive function.

Adverse pregnancy outcomes and pharyngeal flow limitation during sleep: Nulliparous Pregnancy Outcomes Study Monitoring Mothers-to-be (nuMoM2b).

Background: Pharyngeal flow limitation during pregnancy may be a risk factor for adverse pregnancy outcomes but was previously challenging to quantify. Our objective was to determine whether a novel objective measure of flow limitation identifies an increased risk of pre-eclampsia (primary outcome) and other adverse outcomes in a prospective cohort: Nulliparous Pregnancy Outcomes Study Monitoring Mothers-to-be (nuMoM2b).

Methods: Flow limitation severity scores (0%=fully obstructed, 100%=open airway), quantified from breath-by-breath airflow shape, were obtained from home sleep tests during early (6-15 weeks) and mid (22-31 weeks) pregnancy.

Flow Limitation Is Associated with Excessive Daytime Sleepiness in Individuals without Moderate or Severe Obstructive Sleep Apnea.

Moderate-severe obstructive sleep apnea (OSA) (apnea-hypopnea index [AHI], >15 events/h) disturbs sleep through frequent bouts of apnea and is associated with daytime sleepiness. However, many individuals without moderate-severe OSA (i.e.

Reducing crash risk for young drivers: Protocol for a pragmatic randomised controlled trial to improve young driver sleep.

Background: Road trauma is a leading cause of death and disability for young Australians (15-24 years). Young adults are overrepresented in crashes due to sleepiness, with two-thirds of their fatal crashes attributed to sleepy driving. This trial aims to examine the effectiveness of a sleep extension and education program for improved road safety in young adults.

Nasal Pressure Derived Airflow Limitation and Ventilation Measurements are Resilient to Reduced Signal Quality.

Obstructive sleep apnea is a disorder characterized by partial or complete airway obstructions during sleep. Our previously published algorithms use the minimally invasive nasal pressure signal routinely collected during diagnostic polysomnography (PSG) to segment breaths and estimate airflow limitation (using flow:drive) and minute ventilation for each breath. The first aim of this study was to investigate the effect of airflow signal quality on these algorithms, which can be influenced by oronasal breathing and signal-to-noise ratio (SNR).

Sleep mediates the relationship between precarious employment and mental health.

Background: Current evidence suggests that precarious employment is a risk factor for poor mental health. Although the mechanisms underpinning this relationship are unclear, poor sleep has been proposed to have a role in this relationship. This study explored the mediating effects of poor sleep quality and duration on the relationship between precarious employment and mental health.

Increased Flow Limitation During Sleep Is Associated With Increased Psychomotor Vigilance Task Lapses in Individuals With Suspected OSA.

Background: Impaired daytime vigilance is an important consequence of OSA, but several studies have reported no association between objective measurements of vigilance and the apnea-hypopnea index (AHI). Notably, the AHI does not quantify the degree of flow limitation, that is, the extent to which ventilation fails to meet intended ventilation (ventilatory drive).

Research Question: Is flow limitation during sleep associated with daytime vigilance in OSA?

Study Design And Methods: Nine hundred ninety-eight participants with suspected OSA completed a 10-min psychomotor vigilance task (PVT) before same-night in-laboratory polysomnography.

Physiological Determinants of Snore Loudness.

The physiological factors modulating the severity of snoring have not been adequately described. Airway collapse or obstruction is generally the leading determinant of snore sound generation; however, we suspect that ventilatory drive is of equal importance. To determine the relationship between airway obstruction and ventilatory drive on snore loudness.

Precarious employment and associated health and social consequences; a systematic review.

Objective: This systematic review aims to identify, evaluate, and summarise the consequences of precarious employment.

Methods: We included studies published within the last ten years (Jan 2011-July 2021) that employed at least two of three key dimensions of precarious employment: employment insecurity, income inadequacy, and lack of rights and protection.

Results: Of the 4,947 initially identified studies, only five studies met our eligibility criteria.

Oronasal vs Nasal Masks: The Impact of Mask Type on CPAP Requirement, Pharyngeal Critical Closing Pressure (P), and Upper Airway Cross-Sectional Areas in Patients With OSA.

Background: CPAP delivered via an oronasal mask is associated with lower adherence, higher residual apnea-hypopnea index (AHI), and increased CPAP therapeutic pressure compared with nasal masks. However, the mechanisms underlying the increased pressure requirements are not well understood.

Research Question: How do oronasal masks affect upper airway anatomy and collapsibility?

Study Design And Methods: Fourteen patients with OSA underwent a sleep study with both a nasal and oronasal mask, each for one-half of the night (order randomized).

Pathophysiology Underlying Demographic and Obesity Determinants of Sleep Apnea Severity.

Sleep apnea is the manifestation of key endotypic traits, including greater pharyngeal collapsibility, reduced dilator muscle compensation, and elevated chemoreflex loop gain. We investigated how endotypic traits vary with obesity, age, sex, and race/ethnicity to influence sleep apnea disease severity (apnea-hypopnea index [AHI]). Endotypic traits were estimated from polysomnography in a diverse community-based cohort study (Multi-Ethnic Study of Atherosclerosis,  = 1,971; age range, 54-93 yr).

Quantitative and Qualitative Changes in Peripheral Chemoreceptor Activity in Preterm Infants.

Preterm infants are at risk for ventilatory control instability that may be due to aberrant peripheral chemoreceptor activity. Although term infants have increasing peripheral chemoreceptor contribution to overall ventilatory drive with increasing postnatal age, how peripheral chemoreceptor contribution changes in preterm infants with increasing postmenstrual age is not known. To evaluate peripheral chemoreceptor activity between 32 and 52 weeks postmenstrual age in preterm infants, using both quantitative and qualitative measures.

A single dose of noradrenergic/serotonergic reuptake inhibitors combined with an antimuscarinic does not improve obstructive sleep apnoea severity.

Previous trials have demonstrated that the combination of noradrenergic reuptake inhibitors with an antimuscarinic can substantially reduce the apnoea-hypopnoea index (AHI) and improve airway collapsibility in patients with obstructive sleep apnoea (OSA). However, some studies have shown that when administered individually, neither noradrenergic or serotonergic agents have been effective at alleviating OSA. This raises the possibility that serotonergic agents (like noradrenergic agents) may also need to be delivered in combination to be efficacious.

The impact of daytime transoral neuromuscular stimulation on upper airway physiology - A mechanistic clinical investigation.

There is a need for alternatives to positive airway pressure for the treatment of obstructive sleep apnea and snoring. Improving upper airway dilator function might alleviate upper airway obstruction. We hypothesized that transoral neuromuscular stimulation would reduce upper airway collapse in concert with improvement in genioglossal muscle function.