Publications by authors named "Ali Azarbarzin"

Study Objectives: Epiglottic collapse can obstruct the airway in obstructive sleep apnea (OSA) patients in an anteroposterior (E-ap) or lateral direction (E-lat). The present study investigates the concept that lateral or concentric pharyngeal collapse patterns may remodel the epiglottis and predispose it to lateral collapse. To do so, we hypothesized that the presence of-any form of laterally directed pharyngeal collapse, e.

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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.

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The prevalence of obstructive sleep apnea (OSA) is on the rise, driven by various factors including more sensitive diagnostic criteria, increased awareness, enhanced technology through at-home testing enabling easy and cost-effective diagnosis, and a growing incidence of comorbid conditions such as obesity. Treating symptomatic patients with OSA syndrome to enhance quality of life remains a cornerstone approach. However, there is a lack of consensus regarding treatment to improve cardiovascular disease (CVD) outcomes, particularly in light of overall negative results from several randomized controlled trials (RCT) indicating no benefit of positive airway pressure (PAP) therapy on primary and secondary CVD events.

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Article Synopsis
  • The study investigates how obstructive sleep apnea (OSA) affects cognitive function, focusing on the role of hypoxemia (hypoxic burden) as a potential cause of white matter injuries in the brain.
  • Researchers analyzed data from 587 older adults, measuring the association between hypoxic burden and white matter hyperintensity volume (WMH), while considering other factors like ventilatory burden and arousal burden.
  • Findings revealed that an increase in hypoxic burden correlated with higher WMH volume, highlighting the importance of oxygen desaturation in understanding brain health in individuals with OSA.
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Article Synopsis
  • * The panel emphasized the need for improved diagnostic methods, including multi-night assessments and new metrics to differentiate CSA from obstructive sleep apnea, which could enhance treatment outcomes.
  • * Future research should investigate the effects of CSA on patients, optimize therapeutic approaches, and explore new diagnostic techniques and combination therapies for effective CSA management.
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Importance: Mouth breathing is associated with increased airway resistance, pharyngeal collapsibility, and obstructive sleep apnea (OSA) severity. The common belief is that closing the mouth can mitigate the negative effects of mouth breathing during sleep. However, mouth breathing may serve as an essential route to bypassing obstruction along the nasal route (eg, the velopharynx).

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Surgical interventions, like barbed reposition pharyngoplasty (BRP), are a valuable alternative for patients with obstructive sleep apnea (OSA) who are unable to tolerate continuous positive airway pressure (CPAP). However, predicting surgical success remains challenging, partly due to the contribution of non-anatomical factors. Therefore, combined medical treatment with acetazolamide, known to stabilize respiratory drive, may lead to superior surgical results.

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Objective: The efficacy of hypoglossal nerve stimulation (HGNS) therapy is limited by obstruction of the oropharyngeal lateral walls (OLWs). Our objective was to investigate the effect of palatine tonsillectomy on HGNS efficacy in obstructive sleep apnea (OSA) patients with OLW collapse.

Study Design: Case-control study of patients with moderate-to-severe OSA, complete-or-partial OLW collapse, and small tonsils (1 - 2+).

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Article Synopsis
  • * Researchers analyzed 296 participants, with a majority having OSA, using carotid ultrasonography to measure common carotid intima-media thickness (CIMT) and identify atheromatous plaques as indicators of atherosclerosis.
  • * Findings indicate that higher ΔHR is significantly linked to increased CIMT in OSA patients, suggesting ΔHR may serve as a useful biomarker for cardiovascular disease risk in this population.
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Background: Obstructive sleep apnea is characterized by disordered breathing during sleep and is associated with major cardiovascular complications; excess adiposity is an etiologic risk factor. Tirzepatide may be a potential treatment.

Methods: We conducted two phase 3, double-blind, randomized, controlled trials involving adults with moderate-to-severe obstructive sleep apnea and obesity.

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OSA is diagnosed and managed by a metric called the apnea-hypopnea index (AHI). The AHI quantifies the number of respiratory events (apnea or hypopnea), disregarding important information on the characteristics and physiologic consequences of respiratory events, including degrees of ventilatory deficit and associated hypoxemia, cardiac autonomic response, and cortical activity. The oversimplification of the disorder by the AHI is considered one of the reasons for divergent findings on the associations of OSA and cardiovascular disease (CVD) in observational and randomized controlled trial studies.

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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.

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Article Synopsis
  • Differences in the site of pharyngeal collapse can affect the effectiveness of treatments for obstructive sleep apnea (OSA), particularly for patients with complete concentric collapse at the palate (CCCp).
  • Researchers analyzed data from 182 OSA patients to identify specific characteristics in overnight polysomnography that could predict the presence of CCCp, focusing on six flow shape features.
  • Their findings revealed significant associations between certain polysomnographic characteristics and CCCp, leading to enhanced identification methods which were validated with a larger dataset of 466 patients.
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Background: Weight reduction is a standard recommendation for obstructive sleep apnea (OSA) treatment in people with obesity or overweight; however, weight loss can be challenging to achieve and maintain without bariatric surgery. Currently, no approved anti-obesity medication has demonstrated effectiveness in OSA management. This study is evaluating the efficacy and safety of tirzepatide for treatment of moderate to severe OSA in people with obesity.

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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.

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Background: Obstructive sleep apnea is associated with increased blood pressure (BP). Obstructive sleep apnea treatment reduces BP with substantial variability, not explained by the apnea-hypopnea index, partly due to inadequate characterization of obstructive sleep apnea's physiological consequences, such as oxygen desaturation, cardiac autonomic response, and suboptimal treatment efficacy. We sought to examine whether a high baseline heart rate response (ΔHR), a marker of high cardiovascular risk in obstructive sleep apnea, predicts a larger reduction in post-treatment systolic BP (SBP).

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Sleep-disordered breathing (SDB) is a prevalent disorder characterized by recurrent episodic upper airway obstruction. Using data from the Hispanic Community Health Study/Study of Latinos (HCHS/SOL), we apply principal component analysis (PCA) to seven SDB-related measures. We estimate the associations of the top two SDB PCs with serum levels of 617 metabolites, in both single-metabolite analysis, and a joint penalized regression analysis.

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Rationale: Acetazolamide and atomoxetine-plus-oxybutynin ('AtoOxy') can improve obstructive sleep apnoea (OSA) by stabilising ventilatory control and improving dilator muscle responsiveness respectively. Given the different pathophysiological mechanisms targeted by each intervention, we tested whether AtoOxy-plus-acetazolamide would be more efficacious than AtoOxy alone.

Methods: In a multicentre randomised crossover trial, 19 patients with moderate-to-severe OSA received AtoOxy (80/5 mg), acetazolamide (500 mg), combined AtoOxy-plus-acetazolamide or placebo at bedtime for three nights (half doses on first night) with a 4-day washout between conditions.

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Obstructive sleep apnea (OSA) severity is typically assessed by the apnea-hypopnea index (AHI), a frequency-based metric that allocates equal weight to all respiratory events. However, more severe events may have a greater physiologic impact. The purpose of this study was to determine whether the degree of event-related hypoxemia would be associated with the postevent physiologic response.

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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.

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Randomized trials have shown inconsistent cardiovascular benefits from obstructive sleep apnea (OSA) therapy. Intermittent hypoxemia can increase both sympathetic nerve activity and loop gain ("ventilatory instability"), which may thus herald cardiovascular treatment benefit. To test the hypothesis that loop gain predicts changes in 24-hour mean blood pressure (MBP) in response to OSA therapy and compare its predictive value against that of other novel biomarkers.

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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.

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Background: Hypoxic burden (HB) has emerged as a strong predictor of cardiovascular risk in obstructive sleep apnoea (OSA). We aimed to assess the potential of HB to predict the cardiovascular benefit of treating OSA with continuous positive airway pressure (CPAP).

Methods: This was a analysis of the ISAACC trial (ClinicalTrials.

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