How to measure snoring? A comparison of the microphone, cannula and piezoelectric sensor

Abstract

Summary The objective of this study was to compare to each other the methods currently recommended by the American Academy of Sleep Medicine (AASM) to measure snoring: an acoustic sensor, a piezoelectric sensor and a nasal pressure transducer (cannula). Ten subjects reporting habitual snoring were included in the study, performed at Landspitali—University Hospital, Iceland. Snoring was assessed by listening to the air medium microphone located on a patient's chest, compared to listening to two overhead air medium microphones (stereo) and manual scoring of a piezoelectric sensor and nasal cannula vibrations. The chest audio picked up the highest number of snore events of the different snore sensors. The sensitivity and positive predictive value of scoring snore events from the different sensors was compared to the chest audio: overhead audio (0.78, 0.98), cannula (0.55, 0.67) and piezoelectric sensor (0.78, 0.92), respectively. The chest audio was capable of detecting snore events with lower volume and higher fundamental frequency than the other sensors. The 200 Hz sampling rate of the cannula and piezoelectric sensor was one of their limitations for detecting snore events. The different snore sensors do not measure snore events in the same manner. This lack of consistency will affect future research on the clinical significance of snoring. Standardization of objective snore measurements is therefore needed. Based on this paper, snore measurements should be audio‐based and the use of the cannula as a snore sensor be discontinued, but the piezoelectric sensor could possibly be modified for improvement.

Diagnostic accuracy of nasal cannula versus microphone for detection of snoring

“…The cannula has several problems that remain to be solved. In the first place, the 200 Hz sampling rate of the cannula is a limitation on the detection of snore events. Therefore, the cannula only detects frequencies up to 100 Hz as compared to the 4 KHz that the microphone can capture.…”

“…To date, there only has been a single report that has compared the three devices discussed by the AASM (i.e., nasal cannula, microphone, and piezoelectric sensor) using a few patients, but that report was based on individual snore events, expanding the sample satisfactorily. 16 The study found the microphone to be most effective. However, a comprehensive evaluation of the nasal cannula's diagnostic accuracy in snoring detection still is lacking.…”

“…Our study aims to compare the commonly available in‐home cannula with microphone‐based HSAT tests to determine its analytical results and measurement of snoring severity; these two tools were chosen for their accessibility and widespread use in clinical practice. To date, there only has been a single report that has compared the three devices discussed by the AASM (i.e., nasal cannula, microphone, and piezoelectric sensor) using a few patients, but that report was based on individual snore events, expanding the sample satisfactorily . The study found the microphone to be most effective.…”

Objective snoring time and carotid intima‐media thickness in non‐apneic female snorers

“…We performed a full-night home-based sleep study using a T3 device (Nox Medical â , Reykjav ık, Iceland) to measure snoring and AHI (Arnardottir et al, 2015;Cairns et al, 2014). Embedded microphones recorded snoring sound (8 kHz sampling).…”

Models and standards in sleep research and sleep medicine

“…The AASM lists three methods (microphone, nasal pressure transducer and piezoelectric vibration sensor) with no expressed preference. Arnardottir and colleagues (Arnardottir et al ., 2016b) report the well‐presented results of a simple and elegant study in which the three types of sensors are compared. The conclusion is clear: a microphone placed on the chest is the most sensitive method.…”