Direct airflow measurement matters.
When measuring sleep respiratory events, the ‘gold standard’ requires direct airflow measurement. Without it, a sleep test must rely on indirect markers, such as peripheral arterial tonometry (PAT) signals and blood oxygen saturation. These indirect markers are not equipped to detect apnea events too short to result in significant desaturation, nor to accurately differentiate between apneas and hypopneas.
Medications and comorbidities may affect indirect diagnostic methods.
The majority of sleep apnea patients have comorbid conditions that complicate and limit 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.”
*Update: 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
You should not have to wonder whether your home sleep test is acceptable for a specific patient.
Snap’s test measures respiration directly through airflow, effort and sound. Our test has been thoroughly studied, clinically proven, and certified. 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.