Energy Types of Snoring Sounds in Patients with Obstructive Sleep Apnea Syndrome: A Preliminary Observation

Abstract

BackgroundAnnoying snore is the principle symptom and problem in obstructive sleep apnea syndrome (OSAS). However, investigation has been hampered by the complex snoring sound analyses.ObjectiveThis study was aimed to investigate the energy types of the full-night snoring sounds in patients with OSAS.Patients and MethodTwenty male OSAS patients underwent snoring sound recording throughout 6 hours of in-lab overnight polysomnogragphy. Snoring sounds were processed and analyzed by a new sound analytic program, named as Snore Map®. We transformed the 6-hour snoring sound power spectra into the energy spectrum and classified it as snore map type 1 (monosyllabic low-frequency snore), type 2 (duplex low-&mid-frequency snore), type 3 (duplex low- & high-frequency snore), and type 4 (triplex low-, mid-, & high-frequency snore). The interrator and test-retest reliabilities of snore map typing were assessed. The snore map types and their associations among demographic data, subjective snoring questionnaires, and polysomnographic parameters were explored.ResultsThe interrator reliability of snore map typing were almost perfect (κ = 0.87) and the test-retest reliability was high (r = 0.71). The snore map type was proportional to the body mass index (r = 0.63, P = 0.003) and neck circumference (r = 0.52, P = 0.018). Snore map types were unrelated to subjective snoring questionnaire scores (All P>0.05). After adjustment for body mass index and neck circumference, snore map type 3–4 was significantly associated with severity of OSAS (r = 0.52, P = 0.026).ConclusionsSnore map typing of a full-night energy spectrum is feasible and reliable. The presence of a higher snore map type is a warning sign of severe OSAS and indicated priority OSAS management. Future studies are warranted to evaluate whether snore map type can be used to discriminate OSAS from primary snoring and whether it is affected by OSAS management.

Snoring sound energy as a potential biomarker for disease severity and surgical response in childhood obstructive sleep apnoea: A pilot study

“…In other words, patients with high SSE of 801‐1000 Hz had a higher chance of surgical non‐success. Therefore, this non‐contact, non‐invasive, inexpensive technology of snoring sound analysis may have the potential to be a promising tool to screen for severe OSA in children, predict surgical success, and monitor surgical response as in our previous studies on adults with OSA …”

“…We previously reported that the presence of a higher SSE of high‐frequency in adulthood OSA is a warning sign of severe OSA that indicates the need for urgent OSA management . Brietzke and Pusz reported that paediatric snoring has different acoustical characteristics than adult snoring.…”

“…The signals of an analytic window with energy at least 6 dB stronger than background noises were considered to be snore epochs; all others were considered to be noise epochs. Consecutive snore epochs lasting 0.5‐3 second were considered snores, and the snore index (events/min) was calculated. The power spectrum was acquired for each window using fast Fourier transformation (0‐1012 Hz) with a frequency resolution of 4 Hz.…”

“…Several new snoring sound analytic programs have been developed to process and analyse full‐night snoring sounds . Acoustic analysis of snoring sounds represents a non‐contact, non‐invasive, inexpensive technology which has been reported to be able to indirectly locate the sites and degree of upper airway obstructions during sleep .…”

“…Acoustic analysis of snoring sounds represents a non‐contact, non‐invasive, inexpensive technology which has been reported to be able to indirectly locate the sites and degree of upper airway obstructions during sleep . The presence of a higher snoring sound energy (SSE) of high frequency (851‒2000 Hz) in adults with OSA has been reported to be a warning sign of severe OSA and to indicate the need for urgent OSA management . However, the association between SSE and OSA is still unclear in children.…”