Sleep Apnea

Home Sleep Testing: Recent Study Confirms the Importance of Direct Airflow Measurement

By Airflow, Sleep Apnea No Comments

When measuring sleep respiratory events, the ‘gold standard’ is direct airflow measurement. Without it, a sleep test relies on indirect markers, such as peripheral arterial tonometry (PAT) signals and blood oxygen saturation. These indirect markers will not detect apnea events too short to cause significant desaturation, nor will they accurately differentiate between apnea and hypopnea.

Comorbid conditions complicate and limit indirect diagnostic methods

Sleep apnea patients are reported to have high rates of comorbid conditions, which can complicate or limit the effectiveness of indirect diagnostic methods.

A peer-reviewed study published in the Journal of Clinical Sleep Medicine evaluated PAT systems in a large point-of-care cohort, including patients with atrial fibrillation, congestive heart failure, asthma, COPD, and patients receiving pharmacologic therapies. The findings suggest that conditions and therapies which affect normal blood circulation, sympathetic tone, or oxygen saturation often compromise the accuracy of PAT-derived results. In particular, the study concluded, the PAT-based testing presented high rates of diagnostic misclassification of sleep disordered breathing presence or severity.”

A second study published on June 1, 2022 in the Journal of Clinical Sleep Medicine confirmed significant discordance between PAT-based testing and in-lab polysomnography (PSG) among active-duty military personnel. The authors concluded, “PAT-based HSAT may have limited utility for diagnosing OSA and grading severity in this unique patient population.”

Snap Diagnostics’ approach

Snap Diagnostics’ home sleep test is unique in that it integrates the direct, ‘gold standard’ technology and analysis used in traditional laboratory-based sleep tests. It also makes testing more accessible and affordable. As a result, there are no medical conditions or therapies that preclude Snap testing.

To learn more about the published studies supporting this post, please reach out to your local Snap Manager or contact us.

New study finds that setting the optimal pressure for PAP can (and probably should) be done WITHOUT IN-LAB TITRATION

By Sleep Apnea, Treatment No Comments

A recent study published in the Journal of Clinical Sleep Medicine compared manually and automatically derived therapeutic positive airway pressure (PAP) to determine whether the two methods are equivalent. The findings suggest that in-lab manual titrations overestimate therapeutic pressure requirements, particularly in patients with higher BMI. Study participants were adequately treated with lower pressures using auto-titrating positive airway pressure (APAP) while yielding comparable reductions in AHI to those observed during manual titration studies.

The authors reported, “Our findings suggest that, in most cases, split-night or full-night polysomnograms are not necessary to initiate PAP therapy for patients with uncomplicated OSA.”

They added, “Typically, acceptable titration studies generate the highest pressure required to eliminate all obstructive respiratory events, including snoring. This [highest] pressure is not necessarily needed throughout a single night or on a night-to-night basis due to several factors, including sleep position, sleep stage, alcohol use, medications, and exercise.”

For patients receiving PAP therapy, finding the right pressure settings can make a world of difference. Higher than necessary positive airway pressure may cause dry airways and significant discomfort. This is one of the major contributors toward PAP nonadherence in patients with obstructive sleep apnea.

Accordingly, Snap Diagnostics’ home sleep apnea test report includes a prediction for an optimal level of positive airway pressure, using a clinically validated equation. This prediction can be used to optimize and/or shorten the time it takes to achieve optimal pressure settings.

The new findings further strengthen the case for home sleep apnea testing and treatment. As the COVID-19 pandemic has reduced the capacity of overnight sleep centers, providers are shifting away from attended manual PAP titration towards auto-titrating positive airway pressure, particularly for patients with uncomplicated obstructive sleep apnea.

To learn more about the published studies supporting this post, please reach out to your local Snap Manager or contact us.

[1]     Fashanu OS, Budhiraja R, Batool-Anwar S, Quan SF. Titration studies overestimate continuous positive airway pressure requirements in uncomplicated obstructive sleep apnea. J Clin Sleep Med. 2021 May 3. doi: 10.5664/jcsm.9316. Epub ahead of print. PMID: 34165075.
[2]     Miljeteig H, Hoffstein V. Determinants of continuous positive airway pressure level for treatment of obstructive sleep apnea. Am Rev Respir Dis. 1993 Jun;147(6 Pt 1):1526-30. doi: 10.1164/ajrccm/147.6_Pt_1.1526. PMID: 8503565.

Study Suggests Parents Should Take Kids’ Snoring Seriously – Sleep Review

By Brain Health, Children and Adolescence, Sleep Apnea, Snoring No Comments

A large study published in Nature Communications found a link between snoring and structural brain changes in children, as well as problem behaviors such as inattention, hyperactivity and aggression.

Researchers looked at data from MRI brain images of over 10,000 children aged 9 to 10 years in the United States. In addition, they collected data from those children’s parents on how often their kids snore and parent responses to standard behavior measures.

The researchers found a correlation between habitual snoring (three or more nights per week) and thinner gray matter in several areas of the brain, particularly in regions within the frontal lobe which help manage attention, reasoning and impulse control.

This adds to the body of knowledge that snoring is a key component of obstructive sleep disordered breathing, and a predictor of associated behavioral issues in children.

Home Sleep Tests May Fill a Gap in Care for Stroke Patients, Study Finds – Sleep Review

By Brain Health, Heart Health, Sleep Apnea No Comments

Research suggests that treating sleep apnea after a stroke or a mini-stroke can significantly improve recovery and clinical outcome. Sleep Review presents a study abstract published for the American Academy of Neurology (AAN) on how home sleep testing can be used to better serve stroke patients.

Update: We originally wrote about the study abstract. The study has since been published by the American Heart Association (AHA) in Stroke.

Sleep Apnea Tied to Mood Disorders – The New York Times

By Brain Health, Sleep Apnea No Comments

Researchers have found that sleep apnea may increase the risk of developing affective mood disorders, such as depression and anxiety.

A recent study published in JAMA Otolaryngology—Head & Neck Surgery  followed 985 participants for an average of nine years. Over the course of the study, individuals with obstructive sleep apnea were nearly three times as likely to be diagnosed with depression, and nearly twice as likely to be diagnosed with anxiety as those in the control group. Women with sleep apnea were more likely to develop a mood disorder than men.

The researchers concluded that further study of this association “may yield strategies for effective prevention and intervention practices.”

Undiagnosed Sleep Apnea Linked to Accelerated Aging, New Study Finds – Everyday Health

By Sleep and Aging, Sleep Apnea, Women's Health No Comments

Untreated obstructive sleep apnea and other sleep-disordered breathing problems may accelerate aging, according to a study abstract published in the journal Sleep.

Researchers at Harvard Medical School examined blood samples from 622 participants with untreated sleep disordered breathing to look for epigenetic changes in their DNA. Epigenetics refers to changes in the DNA that result from lifestyle and environmental factors. Such changes can affect how genes behave, as well as biological aging.

The researchers found that sleep-disordered breathing is linked to accelerated epigenetic aging, or early aging of the DNA within cells, and that this association increases with the severity of sleep breathing problems. 

The data also showed that sleep disordered breathing leads to more significant epigenetic changes and accelerated aging in women than in men.

Fortunately, epigenetic changes are reversible, and sleep apnea is treatable. Understanding the effect of sleep apnea on aging would have significant implications for better health and longevity.  

Air Pollution May Increase Risk of Sleep Apnea – American Thoracic Society

By Environment, Sleep Apnea No Comments

In a recent study published in the Annals of the American Thoracic Society, researchers explored the link between obstructive sleep apnea and two common air pollutants — nitrogen dioxide (NO2), and a type of fine particle pollution known as PM2.5, produced by power plants, motor vehicles, agricultural fires, and certain industrial processes.

The study found that people who lived in areas with higher amounts of these two types of pollution were more likely to have obstructive sleep apnea. In particular, a participant’s risk of having sleep apnea increased by:

  • 60 percent for each 5 micrograms per cubic meter (μg/m3) increase in yearly PM2.5 exposure
  • 39 percent for each 10 parts per billion increase in yearly NO2

Air pollution harms billions of people on a continuing basis, and may damage health in a number of ways.

Snoring can worsen heart function, especially in women – Medical News Today

By Heart Health, Sleep Apnea, Snoring, Women's Health No Comments

According to a recent study, snoring and sleep apnea may affect cardiac function in women earlier than in men. Women who snored were more likely to have a significant increase in left ventricular mass, making the heart work harder to fulfill the body’s needs.

Findings also suggested that obstructive sleep apnea may be vastly underdiagnosed among snorers.

Treating Sleep Apnea Greatly Improves Stroke Patients’ Recovery – Sleep Review

By Brain Health, Heart Health, Sleep Apnea No Comments

A large study published in the Journal of the American Heart Association found that starting treatment for sleep apnea as early as possible after a stroke or a mini-stroke significantly improves recovery and clinical outcome.

According to the lead author, Dawn Bravata, MD, “We have shown, for the first time in a randomized controlled study, that for individuals who have had a stroke or a TIA—a transient ischemic attack, also known as a mini-stroke— the diagnosis and treatment of sleep apnea with CPAP therapy provides significant benefits, even greater than the benefits of tPA [tissue plasminogen activator], the FDA-approved drug treatment for stroke.” 

The study followed 252 individuals who had strokes or TIAs for up to one year after the event. Two-thirds of the study participants were effectively using CPAP therapy for sleep apnea. Preliminary data suggests that the earlier sleep apnea was treated in stroke patients, the more potent the effect of that treatment.